Urinary Tract Disorders Flashcards
(735 cards)
1
Q
What does azotemia refer to?
A
An increased concentration of nonprotein nitrogenous compounds in blood, usually urea and creatinine.
2
Q
What is prerenal azotemia a consequence of?
A
Decreased renal perfusion (e.g., severe dehydration, heart failure).
3
Q
What causes postrenal azotemia?
A
Interference with excretion of urine from the body (e.g., obstruction, uroabdomen).
4
Q
What is primary renal azotemia caused by?
A
Parenchymal renal disease.
5
Q
What does renal failure refer to?
A
The clinical syndrome that occurs when the kidneys are no longer able to maintain their regulatory, excretory, and endocrine functions.
6
Q
When does renal failure occur?
A
When 75% or more of the nephron population is nonfunctional.
7
Q
What does the term renal disease refer to?
A
The presence of morphologic or functional lesions in one or both kidneys, regardless of extent.
8
Q
What are the key questions to approach renal disease diagnosis?
A
- Is renal disease present? 2. Is the disease glomerular, tubular, interstitial, or a combination? 3. What is the extent of the renal disease? 4. Is the disease acute or chronic? 5. What is the current status of the patient’s renal function? 6. Can the disease be treated? 7. What nonurinary complicating factors are present? 8. What is the prognosis?
9
Q
What specific information about the presenting complaint should be obtained?
A
Onset (acute or gradual), progression (improving, unchanging, or worsening), and response to previous therapy.
10
Q
What questions should be asked regarding urinary tract changes?
A
Changes in water intake, frequency and volume of urination, pollakiuria, dysuria, or hematuria.
11
Q
How can dysuria and pollakiuria be distinguished from polyuria?
A
Dysuria and pollakiuria usually indicate lower urinary tract disease, while polyuria may suggest upper urinary tract disease.
12
Q
Name some potential nephrotoxins.
A
- Ethylene glycol * Chicken jerky treats (dogs) * Easter lilies (cats) * Aminoglycosides * Nonsteroidal antiinflammatory drugs.
13
Q
What is included in a complete physical examination for renal disease?
A
Fundic and rectal examinations, hydration status, presence of ascites or subcutaneous edema, oral cavity examination, and kidney palpation.
14
Q
What might severe hypertension secondary to renal disease cause?
A
Acute onset of blindness caused by retinal detachment.
15
Q
What is the term for marked fibrous osteodystrophy in young animals with renal failure?
A
Rubber jaw.
16
Q
What does hematuria indicate?
A
Any disease that compromises the urogenital mucosa and results in bleeding.
17
Q
How can hematuria be classified?
A
Macroscopic (visible to the naked eye) or microscopic (identified only in urine sediment).
18
Q
What disorders are associated with hematuria?
A
- Urinary tract infection * Neoplasia * Urolithiasis * Trauma * Coagulopathies * Vascular anomalies * Idiopathic renal hematuria.
19
Q
What is important to differentiate during urine sample analysis?
A
Distinguishing pigmenturia from hematuria.
20
Q
What can cystocentesis be associated with?
A
Microscopic hematuria.
21
Q
What should be done when abnormal numbers of red blood cells are observed in urine from cystocentesis?
A
A voided sample should always be obtained.
22
Q
What is dysuria?
A
Painful or difficult urination
Typically manifested as pollakiuria and stranguria.
23
Q
What does the presence of dysuria suggest?
A
Involvement of the lower urinary tract
Such as bladder or urethra.
24
Q
What does painless hematuria suggest?
A
Upper urinary tract involvement
Indicates issues in the kidneys or ureters.
25
What might blood at the beginning of urination indicate?
A disease process in the urethra or genital tract.
26
What might blood at the end of urination signify?
A problem in the bladder or upper urinary tract.
27
Is hematuria more common in dogs with urinary bladder neoplasia or renal neoplasia?
Urinary bladder neoplasia.
28
What are common nonspecific signs in dogs with renal neoplasia?
* Weight loss
* Poor appetite.
29
What does pyuria indicate?
An inflammatory process
## Footnote
Increased numbers of white blood cells in urine sediment.
30
What does hematuria in a voided urine sample suggest?
The urethra or genital tract as the source of bleeding.
31
What increases the suspicion of transitional cell carcinoma?
Abnormal transitional epithelial cells in urine sediment.
32
What should the diagnosis of transitional cell carcinoma be based on?
Histopathologic findings in tissue biopsy samples.
33
Is anemia associated with blood loss common in patients with hematuria?
No, it is uncommon.
34
What may necessitate coagulation tests in hematuria cases?
If the cause remains obscure after routine clinical diagnostic evaluation.
35
What can plain abdominal radiographs identify?
Radiopaque calculi
## Footnote
Examples include struvite and oxalate.
36
What imaging may be needed for radiolucent calculi?
* Double-contrast cystogram
* Positive contrast urethrogram
* Excretory urogram.
37
What can abdominal ultrasonography identify?
Soft tissue lesions such as neoplasia and polypoid cystitis.
38
What characterizes idiopathic renal hematuria?
Urinary bleeding originates in the kidney, cause is obscure.
39
What is the typical age and breed for dogs affected by idiopathic renal hematuria?
Large-breed dogs under 5 years old.
40
What type of hematuria is typically reported in idiopathic renal hematuria?
Severe macroscopic hematuria without discomfort.
41
What may be observed in urine from dogs with idiopathic renal hematuria?
Blood clots.
42
What should be monitored over time in dogs with mild anemia?
Hematocrit.
43
What technique can control renal hemorrhage in idiopathic renal hematuria?
Endoscopically guided sclerotherapy.
44
What is stranguria?
Straining to urinate due to bladder and urethra spasm.
45
What disorders are usually associated with dysuria?
* Cystitis
* Urethritis
* Cystic calculi
* Bladder neoplasia
* Urethral obstruction.
46
What clinical sign is often observed in dogs and cats with dysuric disorders?
Frequent licking at the genital area.
47
What condition in dogs can sometimes present for dysuria?
Perineal hernias.
48
What behavior do dogs and cats exhibit when experiencing dysuria?
They assume the normal posture for urination but take a long time to attempt urination, often passing small volumes
## Footnote
This includes shifting positions and moving to different locations.
49
What can be determined by attempting to pass a urinary catheter?
Whether the urethra is patent or obstructed
50
How can masses and calculi in the bladder be detected?
By palpation when the bladder is empty or partially full
## Footnote
The presence of many small cystic calculi generates a crepitant sensation.
51
What should be included in the examination of all dysuric patients?
Rectal palpation
## Footnote
This helps evaluate the prostate gland in males and identify urethral tumors in females.
52
What is the normal water intake range for dogs?
60 to 90 mL/kg/day
## Footnote
Maximal normal water intake in cats is 45 mL/kg/day.
53
What typically occurs alongside polyuria?
Polydipsia
## Footnote
This is usually a response to polyuria, except in cases of psychogenic polydipsia.
54
What factors can cause variability in normal water intake?
* Ambient temperature
* Respiratory evaporative loss of water
* Exercise level
* Water content of food
* Fecal water content
* Age
* Physiologic state (e.g., pregnancy, lactation)
55
What differentiates pollakiuria from polyuria?
Pollakiuria involves increased frequency of urination, while polyuria involves large volumes of urine with no stranguria
## Footnote
Owners may confuse frequency with volume.
56
What is nocturia in relation to polyuria?
It often accompanies polyuria and may be the first sign detected by the owner
57
What is the logical starting point for the diagnostic evaluation of an animal with PU-PD?
Routine urinalysis, including determination of the USG.
## Footnote
USG stands for urine specific gravity.
58
What is the typical highest USG value found in dogs?
>1.035–1.040, usually found in the morning before eating and drinking.
59
How does USG vary in cats compared to dogs?
USG varies less throughout the day in cats, typically ≥1.035 when eating dry food.
60
What USG values are indicative of normal dogs and cats deprived of water?
Dogs: 1.050 to 1.076; Cats: 1.047 to 1.087.
61
What USG value is expected in sick dogs or cats that are dehydrated?
1.040 or higher.
62
What USG value would cast doubt about the accuracy of the history in an animal presented for evaluation of PU-PD?
>1.025.
63
What is the hyposthenuric USG range?
<1.007.
64
What should be obtained if the USG is in the hyposthenuric or isosthenuric range?
A complete blood count, serum biochemistry profile, and serum thyroxine concentration (in cats).
65
What conditions typically show the lowest USG?
PPD, central diabetes insipidus, and nephrogenic diabetes insipidus.
66
What is the water deprivation test used for?
To evaluate animals with normal blood test results after the initial diagnostic evaluation of PU-PD.
67
What is a typical cause of acute renomegaly?
Acute obstruction of a kidney by a nephrolith.
68
What is the normal kidney length range for feline kidneys?
3.5 to 4.5 cm.
69
What is the expected kidney length for dogs weighing up to 15 kg?
3 to 5.5 cm.
70
What ratio is used to assess kidney size on plain abdominal radiographs?
2.5-3.0-to-1 in cats and 2.5-3.5-to-1 in dogs.
71
What inherited disorder is associated with renomegaly in Bull Terriers and Persian cats?
Autosomal dominant polycystic kidney disease (ADPKD).
72
What mutation causes ADPKD in Persian cats?
A mutation in exon 29 of the polycystin-1 gene.
73
What is the clinical test of choice for identifying ADPKD in affected cats?
Ultrasonography.
74
What is a common cause of renomegaly in cats?
Primary and metastatic renal tumors, often lymphosarcoma.
75
What is the typical presentation of renal lymphoma in cats?
Usually bilateral and often associated with the alimentary form of the disease.
76
What can result from renal obstruction by a nephrolith?
Hydronephrosis and renomegaly.
77
What are perinephric pseudocysts?
Fluid-filled fibrous sacs surrounding the kidney, not lined by epithelium.
78
What is the relationship between perinephric pseudocysts and chronic kidney disease?
Often occur in association with CKD in older cats.
79
What is the diagnostic test of choice for perinephric pseudocysts?
Renal ultrasonography.
80
What is the treatment for perinephric pseudocysts?
Surgical resection of the pseudocyst capsule.
81
What should not be done in cats with unilateral perinephric pseudocysts?
The kidney should not be removed.
82
What can rarely occur alongside perinephric pseudocysts?
Transitional cell carcinoma.
83
What is the significance of evaluating glomerular function?
It is essential for diagnosing renal disease as the glomerular filtration rate (GFR) relates to functional renal mass.
84
What are common screening tests for renal function?
Serum creatinine (SCr) and blood urea nitrogen (BUN) concentrations.
85
Which tests are useful for patients with normal BUN and SCr but suspected renal disease?
Symmetric dimethylarginine (SDMA) and creatinine clearance.
86
What advanced techniques can be used to determine GFR?
Plasma clearance of radioisotopes and renal scintigraphy.
87
What is the purpose of iohexol clearance?
It estimates GFR without urine samples, radioisotopes, or specialized equipment.
88
What does the evaluation of urinary protein excretion assess?
It helps assess the patient for glomerular disease, such as glomerulonephritis and glomerular amyloidosis.
89
How is urea synthesized in the liver?
Via the ornithine cycle from ammonia derived from amino acid catabolism.
90
What is the relationship between BUN concentrations and GFR?
BUN concentrations are inversely proportional to the GFR.
91
What can cause increased BUN concentrations?
Gastrointestinal bleeding, increased catabolism (e.g., starvation, infection), and certain drugs.
92
What factors can decrease BUN concentrations?
Low-protein diets, anabolic steroids, severe hepatic insufficiency, or portosystemic shunting.
93
What are normal BUN concentrations in dogs and cats?
Dogs: 8 to 25 mg/dL; Cats: 15 to 35 mg/dL.
94
What do reagent test strips estimate?
BUN levels in whole blood samples from dogs and cats.
95
What is creatinine?
A nonenzymatic breakdown product of phosphocreatine in muscle.
96
How is the daily production of creatinine determined?
Largely by the muscle mass of the individual.
97
What is the primary method of creatinine excretion?
Almost entirely by glomerular filtration.
98
What method is used to measure creatinine?
Alkaline picrate reaction.
99
What are noncreatinine chromagens?
Substances measured along with creatinine that can constitute up to 50% of measured creatinine at normal serum concentrations.
100
What is the normal SCr concentration in dogs and cats?
Dogs: 0.3 to 1.3 mg/dL; Cats: 0.8 to 1.8 mg/dL.
101
What is the relationship between BUN/SCr and GFR?
It is a rectangular hyperbola; small GFR changes cause small BUN/SCr increases early in renal disease.
102
What is the importance of trending SCr concentrations?
It improves the ability to identify progressive kidney disease and establish prognosis.
103
True or False: The inverse relationship between SCr and GFR is valid only in the steady state.
True
104
What does an increase in BUN or SCr above normal imply?
At least 75% of the nephrons are not functioning
## Footnote
BUN = Blood Urea Nitrogen; SCr = Serum Creatinine
105
Can the magnitude of BUN or SCr predict the cause of azotemia?
No, it cannot predict whether azotemia is prerenal, primary renal, or postrenal in origin
## Footnote
Azotemia refers to an excess of urea and other nitrogenous compounds in the blood.
106
What happens to the BUN-to-creatinine ratio in prerenal and postrenal azotemia?
It may be increased due to increased tubular reabsorption of urea
## Footnote
This occurs at lower tubular flow rates or easier absorption of urea than creatinine.
107
What is SDMA?
A low-molecular-weight by-product of posttranslational methylation of arginine residues in proteins
## Footnote
SDMA = Symmetric Dimethylarginine.
108
How is SDMA removed from the body?
More than 90% is removed by filtration in the kidneys
## Footnote
Thus, its serum concentration serves as an indicator of GFR.
109
What is the relationship between serum SDMA concentration and GFR?
Highly correlated with inulin clearance and SCr
## Footnote
Inulin clearance is the gold standard for GFR determination.
110
What is the normal serum SDMA concentration in adult dogs and cats?
< 14 µg/dL in adult dogs and cats, < 16 µg/dL in puppies and kittens
## Footnote
Indicates healthy kidney function.
111
What is Cystatin C?
A small polypeptide protease inhibitor freely filtered by the glomeruli
## Footnote
It serves as an endogenous marker of GFR.
112
How does age and body weight affect Cystatin C concentration in dogs?
It may be affected by age and body weight, decreases markedly 1 hour after feeding
## Footnote
Returns to normal 12 hours later.
113
What is the clinical utility of serum Cystatin C concentration in dogs and cats?
Does not appear to be a clinically useful indicator of GFR
## Footnote
Studies show unreliable differentiation of GFR levels.
114
What role does FGF-23 play in the body?
It is a phosphate regulatory hormone produced in response to hyperphosphatemia
## Footnote
FGF-23 = Fibroblast Growth Factor-23.
115
What happens to serum FGF-23 concentration in cats with CKD?
It is negatively correlated with survival
## Footnote
Higher concentrations correlate with poorer outcomes.
116
What do NAG and GGT indicate when found in increased urinary concentrations?
Tubular cell injury
## Footnote
NAG = N-acetyl-β-D-glucosaminidase; GGT = γ-Glutamyl Transferase.
117
What is Kidney Injury Molecule-1 (KIM-1)?
A transmembrane protein expressed on the luminal surface of proximal tubular cells
## Footnote
Upregulated after ischemic or toxic injury.
118
What does an increase in NGAL indicate?
Proximal tubular cell injury
## Footnote
NGAL = Neutrophil Gelatinase-Associated Lipocalin.
119
What is the significance of creatinine clearance?
It estimates the GFR based on the renal clearance of a substance
## Footnote
GFR = Glomerular Filtration Rate.
120
What is the formula for renal clearance of a substance?
UxV/Px, where Ux is urine concentration, V is urine volume, and Px is plasma concentration
## Footnote
This relates to the GFR for substances neither reabsorbed nor secreted.
121
What is the endogenous creatinine clearance in dogs and cats?
2 to 5 mL/min/kg
## Footnote
This value helps estimate GFR in these species.
122
What is impaired in chronic progressive renal disease after two-thirds of the nephron population becomes nonfunctional?
Urinary concentrating ability
## Footnote
Azotemia typically does not develop until 75% of nephrons are nonfunctional.
123
What is the main reason to determine endogenous creatinine clearance?
Clinical suspicion of renal disease in a patient with polyuria and polydipsia but normal BUN and SCr
124
What are the requirements for determining endogenous creatinine clearance?
* Accurately timed collection of urine (preferably 12 or 24 hours)
* Determination of patient's body weight
* Serum and urine creatinine concentrations
125
What can erroneously decrease the calculated clearance value in creatinine clearance determination?
Failure to collect all urine produced
126
What is the benefit of using exogenous creatinine clearance?
Eliminates inaccuracy caused by noncreatinine chromagens
127
How does exogenous creatinine clearance compare to endogenous creatinine clearance in dogs?
Exogenous creatinine clearance exceeds endogenous creatinine clearance and closely approximates inulin clearance
128
What factors do not affect the creatinine-to-inulin clearance ratio?
* Sex
* Dietary protein
* Duration of time after renal ablation
129
What methods are used for estimating the GFR in dogs and cats?
* Inulin
* Iohexol
* Creatinine
130
What is iohexol used for?
To estimate the GFR in humans and domestic animals
131
What are the characteristics of iohexol?
* Iodinated
* Water-soluble
* Nonionic
* Low-osmolar contrast agent
132
What is the clearance of iohexol calculated from?
Dose administered divided by the area under the plasma disappearance curve
133
What are the normal values for iohexol clearance in dogs?
* 1.7 to 4.1 mL/min/kg
* 44 to 96 mL/min/m2
134
What are the normal values for iohexol clearance in cats?
* 1.3 to 4.2 mL/min/kg
* 22 to 65 mL/min/m2
135
What are some examples of radioisotopes used to estimate GFR?
* 125I- or 131I-iothalamate
* 51Cr-EDTA
* 99mTc-DTPA
136
What is a major advantage of dynamic renal scintigraphy?
Provides information about individual kidney function
137
What is the urine protein-to-creatinine ratio (UPr/UCr) used for?
To assess the severity of proteinuria in animals with persistent proteinuria
138
What are the IRIS guidelines for UPr/UCr in dogs?
* < 0.2: nonproteinuric
* 0.2–0.5: borderline proteinuric
* > 0.5: proteinuric
139
What is microalbuminuria defined as in humans?
Excretion of 30 to 300 mg/day of albumin in urine
140
What is the definition of microalbuminuria in dogs and cats?
Urine albumin concentration of 1 to 30 mg/dL
141
What is the sensitivity and specificity of semiquantitative tests for microalbuminuria in dogs?
* Specificity: 92%
* Sensitivity: 37%
142
What does the first-generation bladder tumor antigen (BTA) test detect?
A glycoprotein antigen complex associated with bladder neoplasia
143
What are the drawbacks of the BTA test?
High sensitivity but low specificity for detecting transitional cell carcinoma
144
What can cause false positives in the BTA test?
* Marked proteinuria
* Glucosuria
* Pyuria
* Hematuria
145
What factors influence normal urinary concentrating ability?
* Hypothalamic osmoreceptors response
* Release of antidiuretic hormone (ADH)
* Response of the distal nephron to ADH
* Medullary hypertonicity
* Adequate number of functional nephrons
146
What is isosthenuria?
Urine of the same total solute concentration as unaltered glomerular filtrate (USG 1.007–1.015; UOsm 300 mOsm/kg)
147
Define hyposthenuria.
Urine of a lower total solute concentration than glomerular filtrate (USG < 1.007, UOsm < 300 mOsm/kg)
148
What is hypersthenuria?
Urine of a higher total solute concentration than glomerular filtrate (USG > 1.015, UOsm > 300 mOsm/kg)
149
What is the normal range of total urine solute concentration for dogs and cats?
USG 1.001–1.080
150
What is the water deprivation test used for?
Evaluating tubular function in animals with polydipsia and polyuria
151
What parameters are monitored during the water deprivation test?
* Body weight
* Hematocrit
* Plasma proteins
* Skin turgor
* Serum osmolality
* Urine osmolality
* USG
152
What indicates progressive dehydration during the water deprivation test?
Increase in total plasma protein concentration
153
When is the water deprivation test concluded?
When the patient demonstrates adequate concentrating ability or loses 5% or more of its original body weight
154
What is the significance of a urine osmolality increase of less than 5% during the water deprivation test?
Indicates failure to concentrate urine
155
What is the purpose of gradual water deprivation?
To eliminate diagnostic confusion caused by medullary solute washout
156
What is fractional clearance of electrolytes (FCx)?
The ratio of the clearance of the electrolyte to that of creatinine
157
What does a fractional clearance of sodium less than 1% indicate?
Prerenal azotemia and volume depletion
158
What does a fractional clearance of sodium greater than 1% indicate?
Primary parenchymal renal disease
159
What is the normal behavior of fractional clearance of electrolytes in healthy animals?
Much less than 1.0, implying net conservation
160
What is the typical effect of larger molecular weight solutes on urine specific gravity (USG)?
They have a greater effect on specific gravity than on osmolality
161
What is the range of urine osmolality after 5% dehydration for dogs?
1787-2791 mOsm/kg
162
What is the range of urine osmolality after 5% dehydration for cats?
1581-2984 mOsm/kg
163
What is the urine-to-plasma osmolality ratio after 5% dehydration for dogs?
5.7 : 1-8.9 : 1
164
What are normal values for fractional electrolyte excretion of sodium in dogs?
<1%
165
What are normal values for fractional electrolyte excretion of potassium in cats?
<24%
166
What is the effect of age on urine concentration?
Urine concentration decreases with age
167
How does morning urine specific gravity (USG) compare to evening USG?
Morning samples have higher USG values
168
What must be done at the beginning of the water deprivation test?
Empty the bladder and collect baseline data
169
What should be done if an animal has lost 5% or more of its original weight during the water deprivation test?
Administer 0.2 to 0.4 U/kg aqueous vasopressin or 5 µg desmopressin
170
What is the recommended daily water intake restriction for gradual water deprivation?
* 60 mL/lb/day 72 hours before
* 45 mL/lb/day 48 hours before
* 30 mL/lb/day 24 hours before
171
What is the disadvantage of calculating fractional excretion values from spot urine samples?
Highly variable and do not correlate well with values from 72-hour urine samples
172
What are the methods for collecting urine for urinalysis?
Voiding (midstream sample), catheterization, cystocentesis
## Footnote
Cystocentesis is preferred due to less contamination.
173
Why is cystocentesis preferred for urine collection?
Prevents contamination, simple to perform, negligible risk of infection, well tolerated
## Footnote
Particularly useful when evaluating hematuria.
174
What should be done to refrigerated urine before urinalysis?
Warm to room temperature
175
What are the three parts of urinalysis?
* Physical properties
* Chemical properties
* Sediment evaluation
176
What causes normal urine to appear yellow?
Presence of urochrome pigment
177
What does a red or reddish-brown color in urine usually indicate?
Presence of RBCs, hemoglobin, or myoglobin
178
What is the most common abnormal odor in urine?
Ammoniacal odor due to urease-producing bacteria
179
What does USG stand for and what does it reflect?
Urine Specific Gravity; reflects total solute concentration
180
What is the best technique for estimating USG in general practice?
Refractometry
181
What urine pH range is considered normal for dogs and cats?
5.0 to 7.5
182
What can cause acidic urine pH?
* Meat protein-based diet
* Administration of acidifying agents
* Metabolic acidosis
* Respiratory acidosis
* Paradoxic aciduria in metabolic alkalosis
* Protein catabolic states
183
What can cause alkaline urine pH?
* UTI by urease-positive bacteria
* Plant protein-based diet
* Urine exposure to air
* Postprandial alkaline tide
* Administration of alkalinizing agents
* Metabolic alkalosis
* Respiratory alkalosis
* Distal renal tubular acidosis
184
What is a common finding in normal dogs' urine regarding protein concentration?
Small amounts of protein (up to 50 mg/dL)
185
What does persistent, moderate to heavy proteinuria suggest?
Highly suggestive of glomerular disease
186
Under what condition will glucose appear in the urine?
When blood glucose concentration exceeds the renal threshold
187
What is the renal threshold for glucose in dogs and cats?
Approximately 180 mg/dL in dogs and 300 mg/dL in cats
188
What are common causes of glucosuria?
* Diabetes mellitus
* Stress or excitement in cats
* Administration of glucose-containing fluids
* Renal tubular diseases
189
What are the ketones found in urine?
* β-hydroxybutyrate
* Acetoacetate
* Acetone
190
What causes ketonuria?
* Diabetic ketoacidosis
* Starvation or prolonged fasting
* Glycogen storage disease
* Low-carbohydrate diet
* Persistent fever
* Persistent hypoglycemia
191
What does a positive dip strip test for blood not differentiate between?
Erythrocytes, hemoglobin, and myoglobin
192
What is the most common abnormal pigment found in urine?
Free hemoglobin
193
What can cause bilirubinuria?
* Hemolysis
* Liver disease
* Extrahepatic biliary obstruction
* Fever
* Starvation
194
What is the source of bilirubin in urine?
Breakdown of heme by the reticuloendothelial system
195
What is a limitation of the leukocyte esterase test in cats?
Moderately sensitive but not specific (many false-positive results)
196
What percentage of dogs and cats with normal urine findings may have urinary sediment abnormalities?
3% to 16%
## Footnote
This includes abnormalities such as pyuria, bacteriuria, and microscopic hematuria.
197
Why should urine sediment examination be performed on fresh urine samples?
Casts and cellular elements degenerate rapidly at room temperature
## Footnote
Fresh samples provide more accurate results.
198
What is the recommended centrifugation speed and time for urine sediment examination?
1000 to 1500 rpm for 5 minutes
## Footnote
Proper centrifugation ensures adequate sediment collection.
199
How are the number of casts recorded during urine sediment analysis?
Per low-power field (lpf)
## Footnote
This differs from the recording of RBCs and WBCs.
200
What is the normal range of red blood cells (RBCs) in a voided urine sample?
0 to 8/hpf
## Footnote
This indicates occasional RBC presence is normal.
201
What term describes excessive numbers of RBCs in urine?
Hematuria
## Footnote
Hematuria can be microscopic or macroscopic.
202
What is the normal range of white blood cells (WBCs) in a catheterized urine sample?
0 to 5/hpf
## Footnote
Occasional WBC presence is also considered normal.
203
What is the term for an increased number of WBCs in urine sediment?
Pyuria
## Footnote
Pyuria indicates inflammation in the urinary tract.
204
What can the presence of white blood cell casts indicate?
Renal origin of inflammation
## Footnote
White cell casts help localize the lesion.
205
What types of epithelial cells may be found in urine sediment?
Squamous and transitional epithelial cells
## Footnote
Their diagnostic significance is generally low.
206
What are transitional epithelial cells derived from?
Urothelium from the renal pelvis to the urethra
## Footnote
Their size increases from the renal pelvis to the urethra.
207
What are casts in urine sediment primarily composed of?
Aggregated proteins or cells
## Footnote
They indicate a disease process within the kidney.
208
What are the types of casts that can be observed in urine sediment?
Hyaline, granular, cellular, and waxy
## Footnote
Each type has different implications for kidney health.
209
What are hyaline casts composed of?
Tamm-Horsfall mucoprotein and albumin
## Footnote
They can indicate renal diseases associated with proteinuria.
210
What do coarse and fine granular casts suggest?
Ischemic or nephrotoxic renal tubular injury
## Footnote
They represent the degeneration of cells in other casts.
211
What term describes the excretion of abnormal numbers of casts in urine?
Cylindruria
## Footnote
This indicates a pathological condition.
212
What conditions can affect the solubility of crystals in urine?
Urine pH, temperature, and specific gravity
## Footnote
These factors influence crystal formation.
213
What type of crystals are typically found in acidic urine?
Uric acid, calcium oxalate, and cystine
## Footnote
These are common in certain conditions.
214
What are struvite crystals associated with?
Idiopathic lower urinary tract disease and struvite urolithiasis
## Footnote
They can also be found in normal urine.
215
What is indicated by the presence of calcium oxalate crystals in urine of animals with oliguric AKI?
Ethylene glycol intoxication
## Footnote
This is a critical finding in urine sediment analysis.
216
What can commonly be found in urine samples from normal intact male dogs?
Sperm
## Footnote
Rarely, parasite ova of Dioctophyma renale or Capillaria plica may also be observed.
217
What may refractile lipid droplets in urine indicate?
Diabetes mellitus or nephrotic syndrome
## Footnote
They may also occur in cats due to degeneration of lipid-laden tubular cells.
218
What is required to diagnose a urinary tract infection (UTI) conclusively?
Microbiology
## Footnote
Clinical signs and urinalysis findings provide supportive evidence.
219
Which bacteria account for most UTIs in dogs and cats?
Aerobic gram-negative bacteria
## Footnote
Escherichia coli is the most common organism implicated.
220
What is the recommended urine collection method for diagnosing UTIs in female dogs?
Cystocentesis
## Footnote
This method should yield sterile results in normal animals.
221
What is the significance of bacterial growth ≥ 105 cfu/mL in urine from catheterization in female dogs?
May result in false-positive results for UTI
## Footnote
Catheterization itself may also cause UTI in 20% of normal female dogs.
222
What is considered compatible with UTI in male and female cats?
Growth of ≥ 103 cfu/mL from catheterization samples
223
What does radiography provide information about in the kidneys?
Renal size
## Footnote
This information is often not obtainable from physical examination.
224
What is the normal kidney-to-L2 ratio in dogs?
2.5:1 to 3.5:1
## Footnote
In cats, the ratio is 2.4:1 to 3.0:1.
225
What is excretory urography used to evaluate?
Abnormalities in renal size, shape, or location
## Footnote
It also assesses filling defects and certain congenital defects.
226
What is a major advantage of renal ultrasonography?
Allows characterization of internal renal architecture
## Footnote
It is noninvasive and does not depend on renal function.
227
What is the renal length range in normal cats as determined by ultrasonography?
3.0 to 4.3 cm
228
What does cystometrography evaluate?
Detrusor function in dogs and cats
## Footnote
It assesses bladder filling volume and compliance.
229
What does a urethral pressure profile (UPP) evaluate?
Pressure along the length of the urethra
230
What is urethrocystoscopy used for?
Visual inspection of the lower urinary tract
## Footnote
It is the gold standard for diagnosing ectopic ureters.
231
What is a common indication for renal biopsy in dogs and cats?
Proteinuria
232
What is the normal value for the resistive index (RI) in nonsedated dogs?
Approximately 0.6
## Footnote
An upper limit of 0.7 is suggested for cats.
233
True or False: Excretory urography should not be performed in dehydrated patients.
True
234
What can renal hyperechogenicity indicate in cases of ethylene glycol intoxication?
Deposition of calcium oxalate crystals in the kidneys
235
What does the cystometrography procedure monitor?
Intravesical pressure and volume infused
236
Fill in the blank: The technique of ________ allows for the diagnosis of several lower urinary tract disorders.
urethrocystoscopy
237
What is the primary purpose of a renal biopsy?
To establish a histologic diagnosis and alter patient management
## Footnote
Examples include differentiating protein-losing glomerular diseases and determining the status of tubular basement membranes in AKI.
238
What are common indications for renal biopsy in dogs and cats?
Proteinuria
## Footnote
Proteinuria is frequently assessed through renal biopsy.
239
List the techniques available for renal biopsy.
* Blind percutaneous
* Laparoscopic
* Keyhole
* Open
* Ultrasonography-guided
240
Which renal biopsy technique is effective in cats and why?
Blind percutaneous technique because their kidneys can be readily palpated and immobilized
241
What are the advantages of the laparoscopic technique for renal biopsy?
* Direct visualization of the kidney
* Detection of hemorrhage
242
What is the recommended biopsy technique if a larger sample is required?
Wedge biopsy via laparotomy
## Footnote
This allows visual inspection of kidneys and other abdominal organs.
243
What is the role of ultrasonography in renal biopsy?
Allows specific regions of the kidney to be selected for biopsy and evaluation of hemorrhage postbiopsy
244
What should be evaluated before performing a renal biopsy?
Clotting ability, hematocrit, and plasma protein concentration
245
What are the most commonly used biopsy instruments?
* Franklin-modified Vim Silverman needle
* Tru-Cut biopsy needle
246
What should be avoided to prevent insufficient renal cortex retrieval during biopsy?
Excessive penetration of the kidney with the outer cannula of the biopsy instrument
247
What is the recommended direction for the biopsy needle during kidney sampling?
Along the long axis of the kidney, solely through cortical tissue
248
What is the recommended preservation method for biopsy samples for routine histopathology?
Fixed in buffered 10% formalin for at least 3 to 4 hours
249
What should be done after renal biopsy to prevent clot formation?
Initiate a brisk fluid diuresis
250
What is the most common complication of renal biopsy?
Hemorrhage
251
What is the incidence of severe hemorrhage after renal biopsy in dogs and cats?
10% in dogs and 17% in cats
252
What may occur if the renal pelvis is penetrated during a renal biopsy?
Bleeding and clot formation leading to hydronephrosis
253
What should be monitored after renal biopsy to detect serious hemorrhage?
Hematocrit and plasma protein concentration at appropriate intervals over the next 12 to 24 hours
254
What is glomerular disease?
An important cause of chronic kidney disease (CKD) in humans and recognized in veterinary medicine
255
What is the consequence of destruction of the glomerulus?
It renders the remainder of the nephron nonfunctional and can lead to renal failure
256
List important glomerular diseases of dogs
* Glomerulonephritis (GN)
* Glomerular amyloidosis
* Familial glomerular basement membrane (GBM) disorders
* Glomerular sclerosis
257
How does glomerulonephritis (GN) in cats compare to dogs?
GN is less common in cats
258
What is the hallmark of primary glomerular disease?
Marked, persistent proteinuria
259
Define nephrotic syndrome
A condition characterized by proteinuria, hypoalbuminemia, hypercholesterolemia, and edema or ascites
260
True or False: Most dogs and cats with glomerular disease show clinically detectable ascites at presentation.
False
261
What is nephrotic-range proteinuria in humans?
Excreting more than 3.5 g protein/1.73 m2 body surface area/day
262
What is the glomerulus?
A unique vascular structure consisting of a capillary bed between two arterioles
263
What type of barrier does the glomerular capillary wall provide?
A size- and charge-selective barrier
264
What macromolecules does the glomerular capillary wall exclude?
Macromolecules more than 35 Å in radius
265
What are the three layers of the filtration barrier in the glomerulus?
* Capillary endothelium
* Glomerular basement membrane (GBM)
* Podocyte foot processes
266
What is the role of mesangial cells in the glomerulus?
Provide structural support, produce mesangial matrix, and clear filtration residues
267
What can lead to glomerular sclerosis?
Inflammation and progression of CKD due to mesangial cell activity
268
What do the parietal epithelial cells line?
The urinary side of the glomerular capsule (Bowman's capsule)
269
What is the juxtaglomerular apparatus?
A structure that mediates tubuloglomerular feedback
270
What types of mechanisms can cause glomerular injury?
* Immune-mediated
* Non-immune-mediated
271
What is immune complex GN?
Caused by deposition of immunoglobulins or complement in the glomerular capillary wall
272
How can immune complexes deposit in the glomeruli?
* Trapping of soluble circulating immune complexes
* Formation in situ in response to antigens
273
What pattern indicates glomerular deposition of preformed immune complexes?
Lumpy bumpy or granular discontinuous immunofluorescence pattern
274
What can happen due to immune complex deposition in glomeruli?
Decrease in fixed negative charge and increased filtration of negatively charged macromolecules
275
What is a characteristic of activated neutrophils in the glomeruli?
Release of reactive oxygen species and proteinases
276
What is minimal change nephropathy associated with?
Loss of negative charge and foot process fusion leading to severe proteinuria
277
True or False: True autoimmune GN with antibodies against endogenous GBM antigens has been conclusively identified in dogs and cats.
False
278
What leads to glomerular sclerosis?
The continued deposition of immune complexes and release of inflammatory mediators
## Footnote
This process may result in ischemia of the tubules and tubulointerstitial disease, potentially progressing to chronic kidney disease (CKD).
279
How does proteinuria contribute to tubulointerstitial disease?
Proteinuria promotes interstitial inflammation and is resorbed and degraded by proximal tubular cells, leading to cell damage and death
## Footnote
Increased protein reabsorption also upregulates inflammatory mediators.
280
What is membranous glomerulonephritis characterized by?
Primarily by basement membrane thickening
## Footnote
This is a classification of glomerulonephritis based on morphological characteristics.
281
What are the histopathologic lesions of glomerulonephritis?
Basement membrane thickening, hypercellularity, or both
## Footnote
These lesions help classify the type of glomerulonephritis.
282
What does the presence of electron-dense deposits in glomeruli indicate?
The presence of immune complexes
## Footnote
This can be detected by electron microscopy.
283
What is amyloidosis?
A diverse group of diseases characterized by extracellular deposition of fibrils formed by polymerization of protein subunits
## Footnote
These deposits have a specific biophysical conformation called the β-pleated sheet.
284
What is the hallmark appearance of amyloid deposits under light microscopy?
Homogeneous eosinophilic appearance when stained by hematoxylin and eosin (H&E)
## Footnote
They also demonstrate green birefringence after Congo red staining under polarized light.
285
What types of amyloidosis syndromes exist?
Localized and systemic syndromes
## Footnote
Localized syndromes usually affect one organ, while systemic syndromes affect multiple organs.
286
What characterizes reactive (secondary) amyloidosis?
Tissue deposition of amyloid A protein (AA amyloid)
## Footnote
It is often associated with chronic inflammatory conditions.
287
What is serum amyloid A protein (SAA)?
An acute-phase reactant synthesized by the liver in response to tissue injury
## Footnote
Its concentration increases significantly during inflammation.
288
In which species is reactive amyloidosis most common?
Dog
## Footnote
It is relatively uncommon in other species.
289
What clinical signs are associated with glomerular disease?
Anorexia, weight loss, lethargy, polyuria, polydipsia, vomiting
## Footnote
These signs may occur if more than 75% of the nephron population becomes nonfunctional.
290
What is the hallmark of glomerular disease in laboratory findings?
Marked persistent proteinuria with inactive urine sediment
## Footnote
Increased numbers of hyaline casts may also be observed.
291
What does the UPC ratio help assess?
Proteinuria without the confounding effect of total urine solute concentration
## Footnote
It correlates well with 24-hour urinary protein loss.
292
What indicates a poor prognostic sign in glomerular disease?
A decrease in UPC as glomerular disease advances
## Footnote
This decrease does not necessarily indicate clinical improvement.
293
How does proteinuria relate to CKD progression?
Dogs with UPC ratio of 1.0 or higher had a threefold greater risk of uremic crises and death
## Footnote
In cats, higher UPC ratios correlate with increased risk of death or euthanasia.
294
What breeds are associated with familial forms of membranoproliferative GN?
* Soft-coated Wheaten Terriers
* Brittany Spaniels
* Bernese Mountain dogs
## Footnote
These breeds have specific genetic mutations associated with the disease.
295
What is a common clinical finding in Shar Pei dogs related to glomerular disease?
Previous history of Shar Pei fever
## Footnote
This includes episodic joint swelling and high fever.
296
What does isosthenuria indicate in renal disease?
67% or more of the nephron population has become nonfunctional
## Footnote
This may occur alongside earlier loss of concentrating ability.
297
What are common biochemical abnormalities in chronic renal failure due to glomerulonephritis or amyloidosis?
* Azotemia
* Hyperphosphatemia
* Metabolic acidosis
## Footnote
Hypoalbuminemia and hypercholesterolemia are also frequent findings.
298
What is the effect of ACEi and ARB on systemic blood pressure?
Approximately 10%-15% decrease from baseline.
299
When is additional antihypertensive treatment recommended for patients with glomerular disease?
If systolic blood pressure is > 160 mm Hg and diastolic pressure is > 100 mm Hg.
300
Which calcium channel blocker is typically added to the treatment regimen to manage systemic blood pressure?
Amlodipine (0.1-0.2 mg/kg/day).
301
What is the primary effect of amlodipine in the glomerulus?
It primarily affects the afferent arteriole and has little effect on proteinuria.
302
What are the target blood pressure goals for patients with glomerular disease?
Systolic blood pressure < 150 mm Hg and diastolic pressure < 95 mm Hg.
303
What is the potential benefit of platelet inhibition in glomerular disease?
Decreases intraglomerular coagulation and the risk of thromboembolism.
304
What is the recommended dosage of aspirin for dogs to inhibit platelet cyclooxygenase?
1 to 5 mg/kg PO, q24h.
305
What alternative aspirin dosage may be considered for cats?
5 mg PO, q72h.
306
Which immunosuppressive drugs are mentioned for treatment of immune-mediated GN?
* Corticosteroids
* Cyclosporine
* Cyclophosphamide
* Chlorambucil
* Azathioprine
* Mycophenolate
* Leflunomide
307
Why is the effectiveness of immunosuppressive drugs in veterinary medicine unclear?
No studies clearly demonstrate their effectiveness.
308
What adverse effect can corticosteroid administration cause in dogs?
Proteinuria.
309
What was the finding of a controlled trial of cyclosporine in dogs with GN?
Failed to show a beneficial effect.
310
What is the recommended dosage of azathioprine for immunosuppression in dogs?
50 mg/m2 PO, q24-48h.
311
How long does azathioprine require to be fully effective in dogs?
2 to 5 weeks.
312
Why should azathioprine not be used in cats?
Cats metabolize the drug very slowly, leading to bone marrow suppression and severe leukopenia.
313
What alternative drug can be used in cats instead of azathioprine?
Chlorambucil.
314
What is unclear regarding corticosteroids in the treatment of cats with GN?
Whether they are beneficial.
315
What is the mechanism of action of mycophenolate?
Inhibits purine synthesis.
316
What are the primary adverse effects of mycophenolate?
Gastrointestinal and reversible upon discontinuation.
317
What does leflunomide inhibit?
Pyrimidine synthesis.
318
What potential adverse effects are associated with higher dosages of leflunomide?
Unexplained hemorrhage and thrombocytopenia.
319
What is the primary measure for gauging response to treatment of GN?
Change in UPC, serum creatinine, and albumin concentrations
## Footnote
Serum creatinine and albumin concentrations should be abnormal at the start of treatment for proper assessment.
320
How often should a patient be assessed during the initial phase of treatment for GN?
Every 2 weeks
321
What is the recommended duration for continuing immunosuppressive therapy if tolerated?
8 to 12 weeks
322
What should be done if there is minimal response to immunosuppressive therapy?
Increase dosage or try alternative drugs
323
What is the prognosis for patients with systemic AA amyloidosis when SAA concentrations remain low?
Most favorable
324
What drug binds to glycosaminoglycan binding sites on SAA protein?
Eprodisate
325
What recent treatment showed promise in human patients with AA amyloidosis?
Tocilizumab
326
What is the mechanism of action of colchicine in preventing amyloidosis?
It impairs the release of SAA from hepatocytes
327
What genetic disorder is characterized by recurrent febrile episodes and may lead to amyloidosis?
Familial Mediterranean fever (FMF)
328
What is a common adverse effect of colchicine?
Gastrointestinal upset
329
What is the primary stimulus for increased hepatic synthesis of albumin in nephrotic syndrome?
Low plasma oncotic pressure
330
What hypothesis involves activation of the RAAS in the context of nephrotic syndrome?
Underfill hypothesis
331
What does the overfill hypothesis suggest about sodium retention in nephrotic syndrome?
It suggests a primary intrarenal mechanism of sodium retention
332
What are the two mechanisms proposed for sodium retention in nephrotic syndrome?
* Underfill hypothesis
* Overfill hypothesis
333
What state does nephrotic syndrome result in regarding coagulation?
Hypercoagulable state
334
What factors contribute to hypercoagulability in nephrotic syndrome?
* Mild thrombocytosis
* Loss of antithrombin
* Hyperfibrinogenemia
* Decreased fibrinolysis
335
What percentage of dogs with nephrotic syndrome are reported to experience thromboembolism?
15% to 25%
336
What common lipid abnormality is seen in patients with nephrotic syndrome?
Hyperlipidemia
337
What causes increased hepatic synthesis of lipoproteins in nephrotic syndrome?
Decreased plasma oncotic pressure and loss of regulatory factors
338
What condition may lead to systemic hypertension in dogs and cats with glomerular disease?
Sodium retention and activation of the RAAS
339
What is the prognosis for animals with amyloidosis?
Poor prognosis, often less than 1 year after diagnosis
340
What variability exists in the prognosis of GN?
Spontaneous remission, stable course, or progression to chronic renal failure
341
What is the main difference between acute kidney injury (AKI) and chronic kidney disease (CKD)?
AKI is potentially reversible, while CKD is not.
342
What is the expected renal size in patients with AKI?
Normal-sized or mildly enlarged.
343
What renal size finding is indicative of CKD?
Small and irregular or normal.
344
Is a history of previous polyuria and polydipsia present in AKI?
Absent.
345
Is a history of previous polyuria and polydipsia often present in CKD?
Often present, but not always.
346
What type of anemia is often detected in dogs and cats with CKD?
Nonregenerative anemia.
347
What clinical signs suggest CKD in animals?
Weight loss, poor body condition, and poor hair coat.
348
What is the expected size of parathyroid glands in AKI?
Normal-sized (≤4 mm).
349
What is the expected size of parathyroid glands in CKD?
Enlarged (>4 mm).
350
What is the clinical syndrome characterized by abrupt increases in serum creatinine and blood urea nitrogen concentrations?
Acute Kidney Injury (AKI).
351
What can contribute to azotemia and oliguria in AKI?
* Tubular backleak
* Intraluminal tubular obstruction
* Extraluminal tubular obstruction
* Primary filtration failure
352
What is nephrosis historically referred to as?
Acute tubular necrosis.
353
What does severe and prolonged renal ischemia result in?
Decreased cellular energy production and loss of cellular integrity.
354
Which region of the kidney is at increased risk for injury during hypoxia?
Outer medulla.
355
How do NSAIDs contribute to renal ischemia?
By blocking the renal production of vasodilatory prostaglandins.
356
What type of renal injury do true nephrotoxins cause?
Directly on the kidney after binding to tubular cell membranes.
357
What signifies entry into the maintenance phase of AKI?
A critical amount of lethal injury has occurred in the renal tubules
358
How long is the expected course of AKI during the maintenance phase?
1 to 3 weeks
359
What may occur during the maintenance phase of AKI?
Anuria, oliguria, normal urine production, or PU
360
What characterizes the maintenance phase of AKI?
Persistently increased SCr despite correction of prerenal factors
361
What is the prognosis for patients with severe renal injury during the maintenance phase?
The patient may not survive
362
What happens to BUN and SCr during the recovery phase of AKI?
They return to normal as GFR and RBF recover
363
What is a common clinical finding in AKI?
Anorexia, lethargy, vomiting, and diarrhea
364
What percentage of dogs with AKI experienced anuria in a study?
Approximately 18%
365
What physical examination findings may be more severe in AKI than in prerenal azotemia?
Dehydration, uremic breath, and oral ulceration
366
What is the typical urine specific gravity (USG) range in AKI?
1.007-1.015
367
What does the presence of oxalate crystals in urine support?
A diagnosis of ethylene glycol poisoning
368
What is a potential complication of alkali therapy?
Hypernatremia, hyperosmolality, metabolic alkalosis, and ionized hypocalcemia
369
What is the initial fluid of choice for rehydration in AKI?
Normal saline (0.9% NaCl)
370
What should be monitored in AKI patients receiving fluid therapy?
Central venous pressure (CVP)
371
What does urine output less than 2 mL/kg/h indicate?
Relative oliguria
372
What treatment is often necessary for hyperkalemia in oligoanuric patients?
Electrocardiography and potassium management
373
What is the potential impact of hyperphosphatemia in AKI?
Worsening renal lesions and excretory function
374
What diuretics are commonly used in AKI patients?
Osmotic diuretics and loop diuretics
375
What is the dosage for mannitol in AKI treatment?
0.25 to 0.50 g/kg IV
376
What is a key prognostic sign in renal biopsy for AKI?
Presence of intact tubular basement membranes with evidence of tubular regeneration
377
What should be avoided in AKI patients due to loss of renal autoregulation?
General anesthesia and surgery
378
What does a total CO2 concentration of less than 15 mEq/L indicate?
Metabolic acidosis
379
What is the role of intestinal phosphate binders in AKI?
Lower serum phosphorus concentration
380
What may excessive administration of aluminum-containing phosphate binders result in?
Aluminum toxicity
381
What is the expected urine output for normal dogs and cats receiving adequate fluid volume expansion?
2 to 5 mL/kg/h
382
What is the concentration of NaCl mentioned as being more potent than hypertonic dextrose?
0.9% NaCl
383
What are the potential adverse effects of administering 0.9% NaCl?
* Volume overload
* Hyperosmolality
384
Which diuretics are most widely used in AKI patients?
Loop diuretics (e.g., furosemide)
385
What is the initial intravenous dosage of furosemide for AKI patients?
1 to 2 mg/kg IV
386
What should be done if urine output does not increase after administering furosemide?
Discontinue furosemide and consider dopamine or fenoldopam
387
What is a contraindication for the use of furosemide?
Potentiation of aminoglycoside toxicity
388
Where are dopaminergic receptors located in the renal system?
* Renal cortical vasculature
* Renal tubules
389
What is the renal dose of dopamine usually defined as?
2 to 5 µg/kg/min
390
True or False: The use of renal dose dopamine has been documented to be superior to supportive care.
False
391
What is fenoldopam and its primary effect?
A dopamine-1 receptor agonist causing peripheral vasodilatation
392
At what infusion rate does fenoldopam significantly increase GFR and fractional excretion of sodium in dogs?
0.8 µg/kg/min
393
What is the overall survival rate at the time of discharge for dogs with AKI after intermittent hemodialysis?
53%
394
What is a less expensive and more widely available alternative to hemodialysis?
Peritoneal dialysis
395
What is associated with a poor prognosis in AKI patients?
Persistent oliguria or anuria during treatment
396
What are the common causes for death or euthanasia during the initial management of AKI?
* Hyperkalemia
* Metabolic acidosis
* Severe azotemia
* Overhydration leading to pulmonary edema
397
Which intoxication is considered to have a worse prognosis in AKI compared to others?
Ethylene glycol intoxication
398
What percentage of dogs and cats with AKI can be expected to die or be euthanized?
Approximately 50%
399
True or False: Of those that survive AKI, half can be expected to develop chronic kidney disease (CKD).
True
400
What is the definition of Chronic Kidney Disease (CKD)?
CKD culminates in renal failure when compensatory mechanisms are no longer able to maintain the normal excretory, regulatory, and endocrine functions of the kidneys.
401
What constitutes the syndrome of CKD?
Retention of nitrogenous solutes, derangements of fluid, electrolyte, and acid-base balance, and failure of hormone production.
402
How long must abnormalities be present to diagnose CKD?
3 months or longer.
403
What are the stages of CKD according to the National Kidney Foundation?
Five stages of renal disease.
404
What GFR indicates stage 5 CKD?
Less than 17% of normal (<15 mL/min/1.73 m2).
405
What GFR range indicates stage 4 CKD?
17% to 32% of normal (15-29 mL/min/1.73 m2).
406
What does azotemic mean in the context of CKD?
Presence of elevated nitrogenous waste products in the blood.
407
What is the role of SCr in CKD diagnosis?
Serum creatinine (SCr) should be interpreted along with USG and physical examination findings.
408
What is a uremic toxin?
Any compound retained due to decreased renal function that contributes to clinical signs of uremia.
409
What is the best-characterized uremic toxin?
Parathyroid hormone (PTH).
410
What is glomerular hyperfiltration?
An increase in single-nephron GFR in functional remnant nephrons during progressive renal disease.
411
What happens to total GFR after renal ablation?
Total GFR increases approximately 40% to 60% in remnant renal tissue over 4 to 6 weeks.
412
What are the adverse consequences of hyperfiltration?
Proteinuria and glomerular sclerosis in remnant nephrons.
413
What factors may affect the progression of CKD?
Species differences, extent and duration of renal mass reduction, dietary modifications, and complications.
414
What percentage of renal tissue must be destroyed in dogs and cats for progression of CKD?
85% to 95%.
415
What dietary factor can reverse glomerular hyperfiltration in rats?
Dietary restriction of protein.
416
What is the effect of decreasing dietary phosphorus content?
It can reverse renal secondary hyperparathyroidism and slow progression of renal disease.
417
What is glomerulotubular balance?
The principle that the fraction of the filtered load that is resorbed remains constant despite changes in GFR.
418
What is the trade-off hypothesis in renal disease?
Maintaining external solute balance may induce abnormalities of the uremic state.
419
Which solutes are handled by glomerular filtration alone?
Urea and creatinine.
420
What happens to solutes that experience limited regulation as GFR decreases?
Their normal plasma concentrations are maintained until GFR decreases to below approximately 15% to 20% of normal.
421
What solutes experience complete regulation?
Sodium and potassium.
422
What is the clinical herald of polyuria in chronic kidney disease (CKD)?
The onset of polydipsia (PD)
## Footnote
PD is a compensatory response to polyuria (PU) in CKD.
423
What is the defining urine osmolality range indicating defective concentrating ability in CKD?
300 to 600 mOsm/kg
## Footnote
This range corresponds with isosthenuria.
424
What percentage of nephron loss is typically associated with the development of defective concentrating ability in CKD?
67%
## Footnote
This is when significant concentrating defects begin to manifest.
425
What are the key hormones involved in normal calcium and phosphorus metabolism?
* PTH
* 1,25-dihydroxycholecalciferol (calcitriol)
* FGF-23
* Calcitonin
426
What is the effect of hyperphosphatemia on serum ionized calcium concentration in CKD?
It causes a reciprocal decrease
## Footnote
This is explained by the mass law effect.
427
What happens when the [Ca] × [Pi] product exceeds 60 to 70?
Soft tissue mineralization occurs.
428
How does renal secondary hyperparathyroidism develop in CKD?
Due to phosphorus retention causing decreased serum ionized calcium concentration.
429
What is the primary cause of anemia in CKD?
Inadequate production of erythropoietin by the diseased kidneys.
430
What type of anemia is commonly seen in CKD?
Nonregenerative anemia (normochromic normocytic).
431
What causes hemostatic defects in uremic patients?
Qualitative platelet function defects.
432
What are common gastrointestinal disturbances observed in dogs with CKD?
* Erosions and ulcers of the buccal mucosa
* GI hemorrhage
* Vomiting
433
What percentage of dogs and cats with CKD experience systemic hypertension?
20% to 30%
## Footnote
This percentage increases in dogs with glomerular disease.
434
What is the main cause of metabolic acidosis in CKD?
Limitation of renal ammonium excretion.
435
What is the effect of phosphorus restriction in CKD management?
Slows CKD progression and blunts renal secondary hyperparathyroidism.
436
What is the relationship between FGF-23 and CKD?
FGF-23 increases with CKD severity and facilitates phosphate excretion.
437
What is the significance of body weight <4.2 kg at the time of CKD diagnosis?
Associated with significantly shorter survival time.
438
What is the typical response of the diseased kidney to fixed acid load in advanced CKD?
Establish a new steady state at lower than normal plasma bicarbonate concentration.
439
What is the role of calcitriol in calcium absorption?
| vitamin D (active form)
It enhances intestinal absorption of calcium.
440
What changes occur in platelet function in CKD?
* Abnormal platelet adhesiveness
* Decreased clot retraction
* Decreased thromboxane production
441
What is the primary gastric lesion observed in cats with CKD?
Fibrosis and mineralization.
442
What effect does alkali therapy have on CKD?
May slow the progression of CKD.
443
What is the typical lifespan of red blood cells in uremic patients?
Approximately 50% of that in healthy individuals.
444
What is the impact of renal calcitriol production impairment on PTH secretion?
It leads to increased PTH secretion due to decreased feedback.
445
What clinical signs suggest the possibility of glomerular disease?
Presence of subcutaneous edema or ascites
## Footnote
Glomerular disease refers to conditions affecting the glomeruli of the kidneys.
446
What may be observed on the CBC in CKD patients, and what can mask this observation?
Nonregenerative anemia may be observed, masked by dehydration
## Footnote
CBC stands for complete blood count.
447
What reflects the stress of chronic disease in blood tests?
Mature neutrophilia and lymphopenia
## Footnote
Neutrophilia is an increase in neutrophils, while lymphopenia is a decrease in lymphocytes.
448
What is typically normal in patients with CKD unless oliguria or anuria develop?
Serum potassium concentrations
## Footnote
Oliguria refers to low urine output, while anuria refers to no urine output.
449
What is the level of kidney function loss associated with azotemia?
75% or more nephrons are nonfunctional
## Footnote
Azotemia refers to an accumulation of nitrogenous waste products in the blood.
450
What is hyperphosphatemia observed at in terms of nephron function?
85% or more nephrons are nonfunctional
## Footnote
Hyperphosphatemia refers to elevated phosphate levels in the blood.
451
What is the typical serum total calcium concentration in CKD patients?
Normal to slightly low or, rarely, high
## Footnote
Calcium levels can be affected by kidney function.
452
What is a late finding in dogs and cats with CKD related to bicarbonate concentration?
Moderate to severe metabolic acidosis
## Footnote
Metabolic acidosis occurs when the body produces excessive quantities of acid.
453
When does isosthenuria develop in dogs?
When 67% or more nephrons become nonfunctional
## Footnote
Isosthenuria refers to urine with a specific gravity that is equal to that of plasma.
454
What urine specific gravity indicates concentrated urine in some cats with CKD?
USG, 1.022-1.067
## Footnote
USG stands for urine specific gravity.
455
What does a urine protein-to-creatinine (UPC) ratio >1.0 indicate?
More rapid progression and increased risk of developing uremic crisis or death
## Footnote
UPC ratio is used to assess proteinuria in urine samples.
456
What does microalbuminuria refer to?
Urine protein concentrations >1 mg/dL but <30 mg/dL
## Footnote
Microalbuminuria is an early indicator of endothelial damage.
457
What does pyuria and bacteriuria suggest?
Presence of urinary tract infection
## Footnote
Pyuria refers to the presence of pus in urine, while bacteriuria refers to bacteria in urine.
458
What can be observed on plain abdominal radiographs in dogs or cats with CKD?
Irregularly shaped or small kidneys
## Footnote
Normal kidney shape and size do not rule out CKD.
459
What is indicated by increased echogenicity of renal tissue on renal ultrasonography?
Loss of corticomedullary distinction
## Footnote
Corticomedullary distinction refers to the differentiation between the cortex and medulla of the kidneys.
460
What is a key principle of conservative treatment for CKD?
Do not be overly pessimistic with severely dehydrated patients
## Footnote
Appropriate IV fluid therapy is crucial for rehydration.
461
What is the purpose of IV fluid therapy in dehydrated CKD patients?
To resolve prerenal azotemia
## Footnote
Prerenal azotemia can occur due to dehydration affecting kidney function.
462
What should be searched for and treated in CKD patients after rehydration?
Potentially reversible causes of renal failure
## Footnote
Examples include pyelonephritis, hypercalcemia, and obstructive nephropathy.
463
What factors may need treatment to prevent aggravating renal disease?
Urinary tract infection, electrolyte or acid-base disturbances, hypertension
## Footnote
Addressing these factors can help manage CKD effectively.
464
What should a treatment plan for CKD aim to maintain?
Fluid, electrolyte, acid–base, and caloric balance
## Footnote
It should also aim to prevent the accumulation of metabolic waste products.
465
What should dogs and cats with CKD have access to at all times?
Fresh water.
466
How do renal diets for dogs and cats compare to regular diets in terms of survival for CKD cats?
Renal diets have shown 12- to 14-month survival compared to 6 to 12 months for regular diets.
467
What are some key characteristics of renal diets compared to regular diets?
Decreased protein, phosphorus, and sodium; increased B vitamins, soluble fiber, ω-3 PUFA, and antioxidants.
468
What type of evidence supports the use of renal diets in dogs and cats with CKD?
Grade I evidence from randomized controlled clinical studies.
469
Why are commercial renal diets preferred over homemade diets for CKD patients?
Commercial diets are more consistent in composition and nutritionally adequate.
470
What is the theoretical benefit of protein restriction in CKD?
Reduction in clinical signs associated with uremia and decreased hyperfiltration in remnant nephrons.
471
When is moderate protein restriction indicated in CKD?
To relieve clinical signs of uremia and promote patient well-being.
472
What is the recommended protein percentage for dogs with CKD?
15%-17% protein.
473
What should be monitored when a dog is on a low-protein diet?
Stable body weight, stable serum albumin concentration, and decreased BUN concentration.
474
What is the minimum protein requirement for healthy adult cats?
20% of calories from protein.
475
What is the recommended daily caloric intake for older animals?
Approximately 40 kcal/kg/day.
476
What dietary supplementation may be renoprotective for CKD patients?
ω-3 PUFAs.
477
What is the advisable sodium content in diets for dogs with CKD?
Approximately 0.2% to 0.3% sodium.
478
What is the effect of severe metabolic acidosis in CKD patients?
It may require sodium bicarbonate treatment.
479
What should be maintained in patients with CKD regarding serum bicarbonate concentration?
At 14 mEq/L or higher.
480
What is the consequence of feeding a high phosphorus diet in CKD?
Worse progression and outcome in CKD.
481
What is the role of phosphorus binders in CKD treatment?
To trap phosphorus in the gut and hasten its excretion.
482
What is the starting dosage for aluminum hydroxide in CKD treatment?
45 mg/kg q12h given with food.
483
What should be monitored when using calcium-containing phosphorus binders?
For the development of hypercalcemia.
484
What is the recommended dosage for sevelamer HCl in CKD patients?
10 to 20 mg/kg q8h given with food.
485
What is a potential adverse effect of using sevelamer?
Constipation.
486
What dietary change may reverse existing renal secondary hyperparathyroidism?
Phosphorus restriction.
487
What is a common treatment for gastrointestinal signs in uremic patients?
H2 receptor antagonists.
488
What is the dosage for famotidine in CKD dogs?
1 mg/kg PO, q24h.
489
What is the potential effect of metoclopramide in CKD patients?
Management of vomiting.
490
What are ACE inhibitors used for in CKD treatment?
To slow the progression of CKD.
491
What is the dosage for enalapril in CKD dogs?
0.5 mg/kg PO, q24h or q12h.
492
What is the purpose of angiotensin receptor blockers in CKD treatment?
To decrease proteinuria.
493
What is the starting dosage of epoetin alfa for CKD anemia?
100 U/kg SQ, three times/wk.
494
What is a potential risk associated with epoetin alfa treatment?
20% to 40% risk of anti-EPO antibody formation.
495
What is the dosage adjustment for darbepoetin alfa in CKD treatment?
0.25-0.5 µg/kg SQ once weekly.
496
What is a significant observation in CKD cats treated with darbepoetin?
Resolution of anemia and improved overall condition.
497
What is the biologic half-life of darbepoietin?
3-fold
## Footnote
The biologic half-life indicates how long the drug remains active in the body.
498
At what dosage can darbepoietin be administered initially?
0.25-0.5 µg/kg SQ once weekly
## Footnote
SQ stands for subcutaneous.
499
What is the target hematocrit range for administering darbepoietin every 2 weeks?
30%
## Footnote
This is the lower end of the target hematocrit range.
500
What adverse effects were observed in some cats treated with darbepoietin?
* Vomiting
* Hypertension
* Seizures
* Fever
## Footnote
These effects were categorized as presumptive adverse effects.
501
What is the active form of vitamin D3 called?
Calcitriol
## Footnote
Calcitriol is crucial for calcium and phosphate metabolism.
502
Which enzyme converts 25-hydroxycholecalciferol to calcitriol?
1α-hydroxylase
## Footnote
This conversion takes place in the tubular cells of the kidney.
503
What stimulates the activity of 1α-hydroxylase?
* PTH
* Hypophosphatemia
## Footnote
PTH is parathyroid hormone.
504
What major effects does calcitriol have on the body?
* Increases intestinal absorption of calcium
* Facilitates PTH-mediated bone resorption
* Increases renal tubular reabsorption of calcium
* Provides negative feedback on PTH synthesis
## Footnote
These actions help maintain calcium homeostasis.
505
What condition can develop due to a relative lack of calcitriol's feedback effect?
Renal secondary hyperparathyroidism
## Footnote
This condition is significant in patients with CKD.
506
What should be controlled before starting calcitriol therapy?
Hyperphosphatemia
## Footnote
This is usually managed through a low-phosphorus diet and oral phosphorus binders.
507
What is the recommended dosage of calcitriol in dogs and cats with CKD?
2.5–3.5 ng/kg/day
## Footnote
This low dosage helps prevent or reverse renal secondary hyperparathyroidism.
508
What is a common adverse effect of anabolic steroids in cats?
Hepatotoxicity
## Footnote
This includes increased liver enzyme activities and other related complications.
509
What is a risk factor for uremic crises in dogs with CKD?
Systemic hypertension
## Footnote
Hypertension can lead to more rapid disease progression and increased mortality.
510
At what systolic blood pressure should dogs and cats be considered for antihypertensive treatment?
* 150 to 159 mm Hg with end-organ damage
* 160 mm Hg or higher regardless of damage
## Footnote
End-organ damage may include cardiovascular or ocular complications.
511
What type of diets are most commercial diets for CKD formulated to be?
Low in salt
## Footnote
Sodium restriction aims to help manage blood pressure.
512
Why are diuretics generally not used to treat hypertension in CKD?
Concern about dehydration and prerenal azotemia
## Footnote
Diuretics may exacerbate these conditions.
513
What is the dosage range for amlodipine in cats for hypertension treatment?
0.625 to 1.25 mg PO, q24h
## Footnote
PO stands for orally.
514
What type of care can some owners provide at home for their pets with CKD?
Subcutaneous fluids
## Footnote
This can improve the animal's quality of life.
515
What should be considered if an owner has difficulty getting their animal to eat?
Feeding tube
## Footnote
This helps ensure adequate caloric intake and medication administration.
516
What factors indicate a poor prognosis in CKD?
* Severe intractable anemia
* Inability to maintain fluid balance
* Progressive azotemia despite treatment
## Footnote
These factors can significantly impact the outcome.
517
What are the built-in defense mechanisms of the urinary tract?
The urinary tract has several mechanisms including:
* Normal micturition and frequent voiding to remove bacteria
* Sterile proximal urethra with microplicae that aid in bacterial removal
* Normal flora in distal urethra, preputial tissues, and vulva producing bacteriocin
* Mucosal secretions like immunoglobulins and glycosaminoglycans preventing uropathogen adherence
* High urine osmolality and urea concentrations inhibiting bacterial growth
## Footnote
These mechanisms are critical for maintaining urinary tract health.
518
What is the prevalence of bacterial cystitis in cats presenting with lower urinary tract signs?
The prevalence of bacterial cystitis in cats is between 1% and 3% in referral institutions and higher in private practices in Europe.
## Footnote
Most young cats with LUTS have disorders such as feline idiopathic cystitis, not bacterial infections.
519
What is the most common uropathogen isolated in dogs with bacterial cystitis?
Escherichia coli, accounting for approximately 50% of all isolates.
## Footnote
Other common bacteria include Staphylococcus, Proteus, Klebsiella, Enterococcus, and Streptococcus spp.
520
Define sporadic bacterial cystitis.
Sporadic bacterial cystitis suggests the animal is otherwise healthy with no underlying comorbidity and has clinical signs associated with the infection.
## Footnote
This term also implies the presence of typical LUTS.
521
What is complicated bacterial cystitis?
Complicated bacterial cystitis implies an underlying comorbidity, such as:
* Anatomic problems (e.g., ectopic ureters)
* Systemic diseases (e.g., diabetes mellitus)
* Urinary tract issues (e.g., urolithiasis)
## Footnote
These comorbidities make the infection more challenging to treat.
522
What is subclinical bacteriuria?
Subclinical bacteriuria is the presence of bacteria in urine with a positive culture but without typical LUTS.
## Footnote
This condition has also been referred to as occult UTI.
523
What are the common clinical signs associated with bacterial cystitis?
Common clinical signs include:
* Stranguria
* Hematuria
* Pollakuria
* Periuria
* Dysuria
## Footnote
These signs may vary in subtlety among different animals.
524
What diagnostic method is recommended for simple sporadic UTI?
A quantitative aerobic bacterial urine culture obtained by cystocentesis is indicated.
## Footnote
Identification and susceptibility testing of the isolated pathogen follow the culture.
525
What factors can predispose dogs and cats to recurrent bacterial cystitis?
Factors include:
* Anatomical or structural defects
* Micturition problems (e.g., urinary incontinence)
* Metabolic abnormalities (e.g., diabetes mellitus)
* Immunosuppressive therapy
## Footnote
These factors facilitate bacterial ascent and infection establishment.
526
What imaging studies are important in recurrent bacterial cystitis evaluation?
Important imaging studies include:
* Survey abdominal radiography
* Abdominal ultrasonography
* Contrast cystourethrography
* Excretory urography
## Footnote
Cystoscopy may also be considered for detailed examination.
527
What is emphysematous cystitis (EC)?
EC is characterized by gas production by bacteria within the bladder wall or lumen, often associated with diabetes mellitus.
## Footnote
It was reported that gas was detected in 51% of dogs with EC.
528
What does recurrent bacterial cystitis imply?
Recurrent bacterial cystitis implies having three or more infections in a 12-month period.
## Footnote
It can be subclassified into relapsing, reinfection, refractory, or persistent infections.
529
Fill in the blank: The most common cause of encrusting cystitis is _______.
Corynebacterium urealyticum
530
True or False: Urine cultures can be costly but are the gold standard for diagnosing bacterial cystitis.
True
## Footnote
Alternative rapid bacterial immunoassays exist but may have inaccuracies.
531
What is the prevalence of subclinical bacteriuria in healthy adult dogs according to one study?
8.9% in one study of 101 healthy adult dogs.
## Footnote
Prevalence rates in cats can vary significantly.
532
What are some factors that may complicate the diagnosis of bacterial cystitis?
Complicating factors include:
* Chronic kidney disease
* Hyperthyroidism
* Underlying neoplasia
* Micturition disorders
## Footnote
These conditions can mask or mimic clinical signs.
533
What does ISCAID recommend for empiric therapy of uncomplicated urinary tract infections?
Urinary antibacterial drugs effective against >90% of urinary isolates
## Footnote
This recommendation is based on available regional susceptibility data.
534
What are the recommended initial therapies for sporadic bacterial cystitis according to ISCAID?
* Amoxicillin (11-15 mg/kg orally q8h)
* Trimethoprim-sulfamethoxazole (15 mg/kg PO q12h)
## Footnote
Amoxicillin with clavulanate is also a reasonable choice when resistance to amoxicillin is likely.
535
Why is ampicillin not recommended for treating uncomplicated urinary tract infections?
Due to poor oral bioavailability.
536
What is the duration of treatment for sporadic UTI in veterinary medicine?
7 to 14 days.
537
What was the finding of the study comparing enrofloxacin and amoxicillin-clavulanic acid in dogs with uncomplicated UTI?
Enrofloxacin (20 mg/kg for 3 days) was not inferior to amoxicillin-clavulanic acid (14 days).
538
What does ISCAID recommend for the duration of therapy for bacterial cystitis?
5 to 7 days.
539
How long is the treatment for dogs and cats with recurrent UTI generally recommended?
Up to 4 weeks.
540
What should be considered if a positive culture is found after starting a drug regimen for recurrent UTI?
Further diagnostic tests for underlying comorbidities.
541
What is the concern regarding prophylactic daily antimicrobial therapy?
Emerging bacterial resistance from exposure to daily suboptimal doses.
542
What alternative approach for recurrent bacterial cystitis has been investigated?
Use of cranberry extract.
543
What was the finding regarding cranberry extract in relation to UTI prevention in dogs?
Did not reduce the risk of UTI in a placebo-controlled trial.
544
What promising treatment was reported for recurrent UTI in a veterinary pilot study?
Intravesicular administration of ASB E. coli 2-12.
545
What is the general treatment approach for subclinical bacteriuria in dogs and cats?
May not always require treatment.
546
What should be done if a clinician is uncertain about the need for antimicrobial therapy in subclinical bacteriuria?
Consider a short course of antimicrobials and reevaluation.
547
What is acute pyelonephritis (APN) commonly caused by?
Bacteria ascending from the lower urinary tract.
548
How can pyelonephritis be classified in veterinary medicine?
Noncomplicated and complicated.
549
What are common symptoms of APN in animals?
* Flank pain
* Dorsal abdominal pain
* Dehydration
* Signs of acute kidney injury.
550
What diagnostic tests should be performed in suspected cases of pyelonephritis?
* Urinalysis
* Urine culture with susceptibility testing
* Imaging studies.
551
What is recommended for empiric antimicrobial therapy in cases of pyelonephritis?
Antimicrobials that reach high tissue levels.
552
What is the conventional duration of antimicrobial therapy for acute pyelonephritis?
4 weeks.
553
What shorter duration of therapy has been shown effective in human medicine for APN?
7 to 14 days.
554
What should be included in the reevaluation of an animal treated for APN?
* CBC
* Serum creatinine
* Urine culture results.
555
What is bacterial prostatitis?
A chronic or acute condition that occurs in sexually intact male dogs, suspected in any intact male dog with a positive urine culture.
556
What are the systemic ramifications of acute prostatitis?
Fever, depression, dehydration, vomiting, diarrhea, and septic shock.
557
What laboratory finding may be present in dogs with acute prostatitis?
Leukocytosis with left shift.
558
What are common clinical signs of acute prostatitis in dogs?
* LUTS
* Purulent or hemorrhagic urethral discharge
* Abdominal pain
* Tenesmus
559
What may be observed on rectal examination of a dog with acute prostatitis?
The prostate may be asymmetric, enlarged, and painful.
560
What are the clinical signs of chronic prostatitis in dogs?
* Lethargy
* Mild LUTS
* No clinical signs
561
How does the prostate feel on palpation in cases of chronic prostatitis?
The prostate can be symmetric and nonpainful.
562
What serious condition can occur as a complication of prostatitis?
Prostatic abscesses can cause life-threatening peritonitis if ruptured.
563
What condition do most dogs with bacterial prostatitis also have?
Bacterial cystitis.
564
What are commonly isolated pathogens in bacterial prostatitis?
Similar to isolates that cause UTIs.
565
When are cultures of the prostate necessary?
When there is a negative urine culture or clinical signs persist despite treatment.
566
What diagnostic imaging techniques should be performed to evaluate the prostate?
* Abdominal ultrasonography
* Retrograde contrast study
567
What should prostatic fluid be analyzed for?
* Cytologic abnormalities
* Aerobic culture
568
How long should antimicrobial treatment for acute prostatitis be continued?
At least 4 weeks.
569
What factors make it difficult to achieve effective antimicrobial levels in the prostate?
The blood–prostate barrier.
570
What type of antibiotics should be chosen for acute prostatitis?
Antimicrobials that penetrate the blood–prostate barrier.
571
Which antibiotics are appropriate for gram-negative infections in the prostate?
* Trimethoprim-sulfamethoxazole
* Chloramphenicol
* Fluoroquinolones
572
What is considered the drug of choice for canine bacterial prostatitis?
Enrofloxacin.
573
What are the characteristics of enrofloxacin that make it suitable for treating prostatitis?
* High lipid solubility
* Low protein binding
* Low MIC profile
* Broad spectrum of activity
574
Why should oral ciprofloxacin not be used as a substitute for enrofloxacin in dogs?
Ciprofloxacin has only approximately 40% bioavailability and is widely variable.
575
What is the typical dose of enrofloxacin for prostatitis in dogs?
10 to 20 mg/kg PO q24h.
576
What surgical option should be performed as soon as the animal is stable?
Castration.
577
What alternative treatment can be used if castration is not an option?
5α-reductase inhibitor, finasteride (0.1-0.5 mg/kg PO q24h).
578
What surgical procedure may be performed for prostatic abscesses?
Omentalization of the prostatic abscess.
579
What is a potential treatment for prostatic cysts?
Ultrasonography-guided drainage.
580
What is urolithiasis?
A common urinary tract disorder of dogs and cats
581
What clinical signs may indicate lower urinary tract problems in dogs and cats?
* Pollakiuria
* Stranguria
* Dysuria
* Hematuria
582
What are the most common uroliths in dogs and cats?
* Calcium oxalate (CaOx)
* Struvite
583
What imaging techniques are used to identify cystine and urate uroliths?
* Contrast cystourethrograms
* Ultrasonography
584
Why is ultrasonography not ideal for visualizing the entire urethra in male dogs and cats?
It is not a good imaging modality for this purpose, and urethroliths could be missed if abdominal radiography is not performed
585
What is the common cause of urethral obstruction in male dogs?
Urethroliths due to their longer, narrower urethra
586
What are the methods of stone analysis mentioned?
* Quantitative crystallographic analysis
* Optical crystallography using polarized light microscopy
* Infrared spectroscopy (IR)
587
What minimally invasive stone removal techniques are mentioned?
* Laparoscopic-assisted cystostomy
* Percutaneous cystolithotomy
* Voiding urohydropropulsion (VUH)
* Basket retrieval via cystoscope
* Holmium:YAG laser lithotripsy
588
What is VUH, and when can it be performed?
Voiding urohydropropulsion can be performed when small calculi are present in the bladder
589
Which breeds of dogs are at higher risk for CaOx urolith formation?
* Bichon Frise
* Miniature Schnauzer
* Pomeranian
* Cairn terrier
* Maltese
590
What is the most common location for CaOx uroliths in dogs and cats?
The bladder
591
What are common clinical signs of ureterolithiasis?
* Decreased appetite
* Weight loss
* Lethargy
* Hiding
* Hematuria
592
What is the sensitivity of survey abdominal radiography for diagnosing ureterolithiasis in cats?
81%
593
What imaging combination has a sensitivity of 90% for ureterolithiasis diagnosis?
Survey radiography and ultrasonography
594
What is the recommended therapy for stable animals with suspected struvite, urate, and cystine calculi?
Dissolution can be attempted
595
What type of stones have no dissolution protocol?
Calcium oxalate (CaOx) calculi
596
What medications may facilitate the passage of ureteral plugs in cats?
* Tamsulosin
* Amitriptyline
597
What is the importance of monitoring fluid status in conservative management of ureterolithiasis?
To ensure the animal is not becoming overhydrated
598
What is the typical survival rate after medical treatment for urolithiasis?
12-month survival rate
599
What is often the best clinicopathologic indicator for assessing ureteral obstruction?
Body weight assessment at least twice daily
## Footnote
This helps to ensure the animal is not becoming overhydrated.
600
In cases of significant intrinsic renal damage, what may not occur after passage of ureteral obstruction?
Immediate improvement in azotemia
## Footnote
Azotemia may persist in cats with severe kidney disease before obstruction.
601
What was the 12-month survival rate after medical treatment of 52 cats with ureteral obstruction?
66%
## Footnote
However, 32% of these cats did not respond to medical therapy.
602
What percentage of cats with ureteral obstruction were euthanized or died within 1 month of diagnosis?
32%
## Footnote
This indicates a significant mortality rate in non-responders to medical therapy.
603
What should be considered if azotemia or pyelonephritis is present in a cat?
Surgery or minimally invasive techniques for restoration of urine flow
## Footnote
Examples include ureteral stents.
604
What aggressive medical management may benefit cats with marked hyperkalemia or fluid overload?
Hemodialysis
## Footnote
This is an urgent intervention to manage severe electrolyte imbalance.
605
What factors should be considered when deciding on surgical intervention for ureteral obstruction?
Number of stones, degree of obstruction, operator experience, availability of equipment
## Footnote
These factors influence the choice between ureterotomy, stenting, or SUB.
606
What is preferred when only a single calculus is identified in ureteral obstruction?
Ureterotomy
## Footnote
Minimally invasive procedures are often chosen for multiple calculi.
607
What are major factors determining recovery of renal function after reestablishing ureteral patency?
Degree of renal dysfunction before obstruction, duration and extent of obstruction
## Footnote
Ureteral strictures can complicate recovery.
608
What complications are less likely to occur with ureteral stenting or SUB compared to ureterotomy?
Ureteral strictures secondary to scar tissue formation
## Footnote
These complications can lead to reobstruction.
609
What was the recurrence rate of ureterolithiasis in a subset of cats followed after surgical intervention?
40%
## Footnote
This indicates a significant risk of recurrence after treatment.
610
What treatment is preferred for ureteral obstruction in cats with multiple ureteroliths?
Placement of ureteral stents or SUB
## Footnote
These procedures have lower morbidity and mortality rates.
611
What advantages are associated with stent placement for ureteral obstruction?
Lower re-obstruction rate, decreased severity of azotemia
## Footnote
These benefits are significant compared to traditional surgical approaches.
612
What surgical technique is used for stent placement in cats?
Laparotomy and coaxial technique
## Footnote
This involves a needle puncture in the kidney and cystotomy.
613
What dietary considerations should be made for cats with renal compromise and hypertension?
Avoid high-sodium diets
## Footnote
Dietary management is crucial for long-term care.
614
What type of diets are recommended for animals with stage II chronic kidney disease or higher?
Renal diets lower in phosphorus and protein
## Footnote
These diets help manage kidney disease effectively.
615
What is recommended to increase moisture content in the diet after urolith removal?
Feeding a canned diet
## Footnote
Increasing dietary moisture can decrease urine concentration of stone mineral precursors.
616
What should be done if urine is still too concentrated after increasing dietary moisture?
Addition of sodium chloride (table salt) to the diet
## Footnote
This should be avoided in hypertensive patients or those with cardiovascular problems.
617
What dietary modifications are suggested for preventing CaOx uroliths?
Avoid calcium restriction; provide high-moisture, lower-calorie, low-oxalate treats
## Footnote
Excess calcium and oxalate intake should be avoided.
618
What nutrients are considered inhibitors of CaOx urolith formation?
Magnesium, phosphate, and citrate
## Footnote
These should not be restricted in the diet.
619
What is the role of hydrochlorothiazide in managing CaOx urolithiasis?
It may decrease urinary calcium excretion
## Footnote
Serum calcium concentration should be monitored to avoid hypercalcemia.
620
How are struvite uroliths generally induced in dogs?
Usually infection-induced by Staphylococcus intermedius or Proteus mirabilis
## Footnote
These bacteria hydrolyze urea, increasing urine pH.
621
What is necessary for the dissolution of canine struvite uroliths?
Proper antimicrobials based on minimum inhibitory concentration (MIC) testing
## Footnote
Antimicrobials should be administered throughout the dissolution protocol.
622
What dietary approach is suggested for preventing struvite stones in cats?
A high-moisture diet producing urine pH less than 6.8
## Footnote
Veterinary diets marketed for struvite prevention may be effective.
623
What is the primary cause of urate urolithiasis in Dalmatians?
Alteration in purine metabolism leading to uric acid excretion
## Footnote
This results in higher uric acid levels compared to other breeds.
624
What is the recommended management for urate urolithiasis in dogs?
A low-protein diet and allopurinol administration
## Footnote
Allopurinol decreases uric acid formation in urine.
625
What should be investigated if urate-containing calculi are found in non-hyperuricosuric breeds?
Underlying portovascular anomalies such as portosystemic shunt (PSS)
## Footnote
Liver disorders can predispose to urate urolith formation.
626
What is a notable characteristic of urate urolithiasis in cats?
No gender predilection; specific breeds like Egyptian Mau and Siamese are at higher risk
## Footnote
The pathophysiology in cats is largely unknown.
627
What is the role of potassium citrate in managing urate urolithiasis?
It helps alkalinize the urine
## Footnote
This is useful in dogs with recurrent urate uroliths.
628
What dietary component should be emphasized in animals that form uroliths?
High moisture content in the diet
## Footnote
This is crucial for all animals prone to urolithiasis.
629
Fill in the blank: Struvite uroliths in dogs are usually larger than _______.
CaOx uroliths
630
True or False: Struvite uroliths in cats are commonly caused by bacterial infections.
False
## Footnote
Unlike dogs, struvite uroliths in cats are not infection-induced.
631
What should be monitored if a cat is placed on a calculolytic diet for struvite urolith dissolution?
Urolith size with radiography
## Footnote
Evaluation should occur 2 to 3 weeks after diet adjustment.
632
What is urate urolithiasis?
A condition where urate crystals form stones in the urinary tract of cats.
633
What diagnostic studies are recommended for cats diagnosed with urate urolithiasis?
A full complete blood count (CBC) and serum biochemical profile.
634
What clinical signs suggest hepatopathy in cats with urate urolithiasis?
Ptyalism, neurologic signs, lethargy.
635
What dietary management is often recommended to prevent recurrence of urate uroliths?
A high moisture diet that is restricted in protein.
636
Name one diet marketed for kidney disease that can be used for cats with urate urolithiasis.
Hill's k/d.
637
What imaging technique is important to monitor for recurrence of urate uroliths?
Ultrasonography.
638
What are apatite-containing calculi commonly associated with?
Struvite uroliths.
639
What is brushite?
Calcium hydrogen phosphate dihydrate, a form of calcium phosphate.
640
What is the recommended dietary therapy for cystine urolithiasis?
A diet high in moisture and low in protein, aiming for urine pH > 6.5 to 7.0.
641
What is the primary cause of cystine urolithiasis in dogs?
A mutation in genes SLC3A1 and SLC7A9.
642
True or False: Silica-containing uroliths are common in cats.
False.
643
What type of uroliths are referred to as DSB calculi?
Dried Solidified Blood calculi identified in cats.
644
What is the management for DSB calculi?
Evaluate for renal or lower urinary hematuria and increase moisture in the diet.
645
What can cause xanthine urolithiasis in dogs?
Iatrogenic administration of the xanthine oxidase inhibitor allopurinol.
646
What is the cornerstone of therapy for preventing urolithiasis recurrence?
Diets high in moisture.
647
What should be done whenever a urolith is obtained from a dog or cat?
Submit it for crystallographic analysis.
648
Fill in the blank: Cystinuria in dogs results from a mutation in one of two genes, SLC3A1 and _______.
SLC7A9.
649
What dietary strategy is recommended for silica urolith prevention?
High-moisture diet that is higher in animal proteins.
650
True or False: Potassium citrate can be used to alkalinize urine in cystine urolithiasis.
True.
651
What does FLUTD stand for?
Feline lower urinary tract disease
652
What are common signs of LUTD in cats?
Pollakiuria, stranguria, periuria, dysuria, hematuria
653
What is the prevalence of LUTS in pet cats in the UK and US?
0.6% to 6.4%
654
What condition is most commonly diagnosed in young cats presenting with LUTS?
Feline idiopathic cystitis (FIC)
655
What is a common complication in male cats with FIC?
Urethral obstruction
656
What factors are associated with an increased risk for FIC?
* Excessive body weight
* Decreased activity
* Multiple cats in the household
* Nonclumping litter
* Indoor housing
* Environmental stressors
657
What are the two forms of histopathology for FIC?
Nonulcerative (type I) and ulcerative (type II)
658
Which form of FIC is most commonly presented in cats?
Nonulcerative form
659
What histopathologic changes can be observed in chronic nonulcerative FIC?
* Intact or damaged urothelium
* Submucosal edema
* Dilation of submucosal blood vessels
* Submucosal hemorrhage
* Increased mast cell density
660
What bladder abnormality has been found in cats with FIC?
Decrease in bladder compliance
661
What role do urothelial cells play in FIC?
Targets of various stimuli that can potentiate inflammation
662
What infectious agents have been studied in relation to FIC?
Feline calicivirus (FCV) and Bartonella spp.
663
True or False: Corticosteroid administration prevents FIC.
False
664
What systemic abnormalities are observed in cats with FIC during stress?
* Elevated catecholamines
* Decreased serum cortisol concentrations
665
What does the waxing and waning course of clinical signs in FIC suggest?
Exacerbation by environmental stressors
666
What is the most common cause of urinary tract obstruction in male cats?
Urethral plugs
667
What is a major difference in urethral obstruction between male and female cats?
Male cats have a narrow penile urethral lumen and are predisposed to obstruction
668
What composition is commonly found in urethral plugs in male cats?
Struvite with a proteinaceous matrix
669
What may contribute to the formation of urethral plugs?
Oozing of plasma proteins into urine during inflammation increases urinary pH
670
Fill in the blank: FIC should not be considered solely a _______.
bladder disease
671
What additional factors should be evaluated in cats with FIC?
* Behavioral problems
* Endocrine problems
* Cardiovascular problems
* Gastrointestinal problems
672
What factors should be considered when choosing diagnostic tests for a cat with LUTS?
The number of episodes, severity of clinical signs, owner's budget
## Footnote
LUTS stands for Lower Urinary Tract Signs.
673
Is there a well-accepted diagnostic test for FIC?
No, FIC currently remains a diagnosis of exclusion.
## Footnote
FIC stands for Feline Idiopathic Cystitis.
674
What percentage of cats with LUTS have cystic calculi?
Approximately 20%
## Footnote
Cystic calculi are bladder stones.
675
What diagnostic imaging is recommended for cats with LUTS?
Abdominal radiography
## Footnote
This helps to identify cystic calculi.
676
What should be performed before a decompressive cystocentesis in a cat with urethral obstruction?
Obtain an abdominal radiograph
## Footnote
Provided the cat is stable.
677
What is the first step in managing a cat diagnosed with urethral obstruction?
Assess and stabilize with intravenous (IV) fluids.
678
What biochemical parameters should be evaluated in a cat with urethral obstruction?
Postrenal azotemia, hyperkalemia, electrolyte and acid-base disturbances
## Footnote
Includes hypocalcemia and acidosis.
679
What treatment is administered if hyperkalemia is present in a cat?
IV fluids, regular insulin, and 50% dextrose
## Footnote
An electrocardiogram should also be evaluated.
680
What are the common calculi reported in cats?
* Struvite * Calcium oxalate (CaOx)
## Footnote
These are types of bladder stones.
681
What is a decompressive cystocentesis?
A procedure to drain urine from the bladder using a needle.
682
What analgesic is recommended for a cat with urethral obstruction?
Buprenorphine, 0.01 mg/kg intravenously q8-12h.
683
What is one method to remove a urethral obstruction in rare cases?
Massaging the distal penis.
684
When is an indwelling urinary catheter indicated?
In cats with severe azotemia, debris in urine, or detrusor atony.
685
What should be monitored in azotemic cats during postobstructive diuresis?
Urine output, renal parameters, potassium concentration
## Footnote
Hypokalemia can develop during diuresis.
686
What drug is often administered to decrease urethral spasms in cats?
α1-antagonists such as phenoxybenzamine or prazosin.
687
True or False: Prazosin has been shown to reduce the incidence of urethral reobstruction in cats.
False.
688
What is the goal of chronic management of FIC?
To keep clinical signs to a minimum and increase disease-free intervals.
689
What does MEMO therapy involve?
Multimodal environmental modifications and client education.
690
What dietary change may benefit cats with FIC?
Increasing water intake by feeding canned food.
691
What is the role of pheromones in managing FIC?
They may reduce anxiety experienced by cats.
692
What is Feliway?
A synthetic feline facial pheromone used to reduce anxiety.
693
What should be considered before using drug therapy for FIC?
Environmental needs must be addressed first.
694
What is the timeline for observing benefits from many drugs used in FIC management?
Longer than 1 week.
695
What is micturition dependent on?
Coordinated actions among the sympathetic, parasympathetic, and somatic nervous systems and central control centers.
696
Where is the pontine micturition center (PMC) located?
In the dorsomedial pontine tegmentum in the brainstem.
697
What type of input does the thoracolumbar sympathetic pathway provide to the bladder?
Excitatory input to the bladder neck and urethra, and inhibitory input to the PS ganglia.
698
What neurotransmitter is released by postganglionic fibers in the sympathetic pathway?
Norepinephrine (NE).
699
What receptors do norepinephrine activate in the urinary bladder?
β-receptors and α-receptors.
700
What is the role of β-receptors in the urinary bladder?
Allow the bladder to relax and fill continuously with little increase in intravesical pressure.
701
What is urinary incontinence (UI)?
Unconscious voiding of urine due to failure of urine storage during filling.
702
What is urge incontinence?
Consciously voiding small amounts of urine in inappropriate locations.
703
What is ectopic ureters (EUs)?
Ureteral openings in an area other than the normal position in the trigone of the bladder.
704
What is the most common cause of UI in young dogs?
Ectopic ureters (EUs).
705
What breeds are over-represented in cases of ectopic ureters?
* Golden Retriever
* Labrador Retriever
* Siberian Husky
* Newfoundland
* English Bulldog
706
What diagnostic procedures can confirm the presence of ectopic ureters?
* Excretory urography
* Fluoroscopic urethrography
* Ureterography
* Abdominal ultrasonography
* Cystoscopy
* Helical computed tomography (CT)
707
What is urethral sphincter mechanism incompetence (USMI)?
Decreased urethral closure pressure leading to urinary incontinence.
708
What disorders can lead to decreased urethral closure pressure?
* Intervertebral disk disease
* Degenerative myelopathy
* Trauma
* Malformations of spinal vertebrae
* Dysautonomia
709
What is the primary demographic affected by USMI?
Spayed bitches, but it can also occur in intact females and male dogs.
710
What hormone is thought to improve urethral closure pressure?
Estrogen.
711
What is the gold standard to document decreased urethral closure pressure?
Urethral pressure profile (UPP).
712
What is the common treatment for USMI?
Drugs aimed at improving urethral pressures via α1-adrenoceptors.
713
What is the FDA-approved estrogen compound for treating USMI?
Estriol (Incurin).
714
What are submucosal urethral bulking agents used for?
To treat dogs refractory to medications or for owners who do not wish to medicate continually.
715
What are some examples of submucosal urethral bulking agents?
* Polydimethylsiloxane (PDMS-Macroplastique)
* Calcium hydroxylapatite (Coaptite)
* Carbon-coated beads (Durasphere)
* Cross-linked bovine collagen material (ReGain)
716
What can lead to secondary bladder dysfunction and overflow incontinence?
Persistent increase in urethral closure pressure from mechanical or functional obstruction.
717
What are some mechanical causes for urinary retention?
* Urethroliths
* Neoplasia
* Proliferative urethritis
* Urethral strictures
* Foreign bodies
* Prostatic diseases
718
What is the typical clinical sign in dogs with ectopic ureters?
Urinary incontinence (UI).
719
What is the significance of obtaining a detailed history in cases of urinary incontinence?
Essential for formulating proper differential diagnoses and an appropriate diagnostic plan.
720
What is a common complaint from owners of dogs with USMI?
Nocturia.
721
What are some causes of urethral obstruction?
Urethral strictures, foreign bodies, urethral plugs, prostatic diseases, extraluminal urethral compressions
## Footnote
Prostatic diseases include abscess, paraprostatic cyst, and benign prostatic hypertrophy.
722
What are functional obstructions associated with?
Suprasacral or brainstem disease, urethritis, mechanical obstruction, idiopathic functional urethral outflow tract obstruction
## Footnote
Idiopathic functional urethral outflow tract obstruction is also known as detrusor-urethral dyssynergia.
723
How is overflow incontinence diagnosed?
Based on history, physical and neurologic examination, imaging of the urinary tract
## Footnote
Watching the animal void and assessing residual urine volume is also helpful.
724
What is the normal residual urine volume after voiding in healthy animals?
Less than 0.5 to 1 mL/kg
## Footnote
This volume should be noted during the assessment of urinary issues.
725
What imaging techniques are beneficial for evaluating mechanical obstructions?
Plain radiography, cystourethrography, cystoscopy
## Footnote
An enema should be given before radiographic studies to evaluate the proximal urethra.
726
What is the purpose of cystoscopy?
Evaluate urethral mucosa, obtain samples for biopsy and culture, aid in urethral stent placement
## Footnote
Cystoscopy can help manage urethral conditions effectively.
727
What is detrusor-urethral dyssynergia (DUD)?
Idiopathic functional urethral outflow tract obstruction
## Footnote
It usually occurs in large-breed male dogs, both castrated and intact.
728
What is the treatment for mechanical obstructions?
Remove the obstruction, urethral stones removal via surgery or holmium:YAG laser lithotripsy
## Footnote
Transitional cell carcinoma (TCC) should be treated with piroxicam or other NSAIDs.
729
What is proliferative urethritis and where is it usually seen?
A condition often seen in female dogs, resulting from chronic UTIs
## Footnote
It can appear as frond-like tissue in the urethral lumen.
730
What treatments are used for proliferative urethritis?
Proper antimicrobials, NSAIDs, azathioprine
## Footnote
A biopsy is necessary to differentiate from TCC.
731
What are α1-adrenoceptor antagonists used for?
To decrease the closure pressure of the internal urethral sphincter
## Footnote
Prazosin is a commonly used α1-adrenoceptor antagonist.
732
What is overactive bladder (OAB) associated with?
Urge incontinence, underlying cystitis, cystic calculi, neoplasia, polyps, drugs
## Footnote
A detailed history is necessary to document other lower urinary tract signs.
733
What is idiopathic OAB (iOAB)?
A form of overactive bladder without a known cause
## Footnote
It may occur with USMI and lead to mixed UI.
734
Which medications can help manage idiopathic OAB?
Oxybutynin, tolterodine, tricyclic antidepressants
## Footnote
Amitriptyline, imipramine, and clomipramine have anticholinergic properties.
735
When should tricyclic antidepressants be used for OAB?
Only when behavioral modifications have been unsuccessful
## Footnote
They should be discontinued when clinical signs improve.
