Urinary Tract Disease Flashcards
(119 cards)
Define: azotemia
abnormal increase in the concentration of non-protein nitrogenous wastes in blood
How much must GFR decrease before azotemia develops?
25%
How much of the nephron population must be non-function for renal failure to occur?
75%
What general signs are associated with renal disease?
o PU/PD, dehydration, melena/hematemesis/vomiting
o Anorexia / GI signs / weight loss (uremia causes GI ulceration)
o Pale mucous membranes (EPO not produced)
o Lethargy
o Blindness (angiotensin II —> vasoconstriction —> high BP)
o Distended abdomen
Define: uremia
the clinical signs and biochem abnormalities associated with critical loss of functional nephrons
Differentiate gross hematuria, occult hematuria, and pseudohematuria.
Gross (macroscopic) - sufficient blood to be apparent to the naked eye
Occult (microscopic) - present but not visible to the naked eye
Pseudo - red to brown urine w/o intact RBC, instead d/t hemoglobin, myoglobin, or chemicals
What is the gold standard measurement of GFR?
What indirect measurement is most commonly used?
Clearance of radioisotopes with renal scintigraphy
Serum creatinine
What are the 4 limitations of using creatinine as a measure of GFR?
- does not tell you why GFR has fallen
- does not discriminate between causes of azotemia, ARF/CRF, or reversible/irreversible renal failure
- severity of CS are not directly proportional to magnitude of increase
- cannot prognosticate magnitude of azotemia
What parameters (5) are evaluated on a urine dipstick?
Protein pH Blood Glucose Ketones
What is considered ‘normal’ SpGr of urine in the dog and cat?
Dog >1.030
Cat >1.035
What is assessed with fractional excretion of electrolytes?
Which electrolyte is most commonly analyzed?
Assessment of tubular dysfunction
Na-fractional excretion (compared to Cr) differentiates prerenal (1%) disease
How is proteinuria detected?
What are the parameters to diagnose proteinuria in cats and dogs?
What condition might give a false positive in this test?
UPC
Cats >0.4 (0.2-0.4 borderline)
Dogs >0.5 (0.2-0.5 borderline)
LUTD causes false positive
What are 5 main ddx for renomegaly?
- Neoplasia
- Renal inflammation
- Amyloidosis
- Hydronephrosis
- Portosystemic shunts
- Polycystic kidney disease
Which renal tumors are more common in dogs?
Describe the CS, Dx, Tx, and prognosis.
Adenocarcinoma
♣ CS: few early on (only affects one kidney), hematuria, weight loss, unilateral renomegaly, rarely azotemia, polycythemia (paraneoplastic), hypertrophic osteopathy (paraneoplastic)
♣ Dx: renal US with FNA
♣ Tx: nephrectomy
♣ Prog: MST 16 months with treatment, ~50% have metastases at diagnosis
Which renal tumors are more common in cats?
Describe the CS, Dx, Tx, and prognosis.
Lymphoma
♣ Usually affects both kidneys
♣ CS: renomegaly, weight loss, inappetence, PU/PD, renal azotemia, tends to spread to CNS
♣ Low to moderate association with FeLV infection
♣ Dx: renal US with FNA
♣ Tx: multi-agent chemotherapy (COP or CHOP), may resolve the azotemia
♣ Prog: 60% complete remission, MST 91 days with treatment
Is acute kidney injury considered reversible?
Yes
What parameters are assessed in IRIS staging of acute renal failure?
Blood Cr concentration
Non-oliguric / oligoanuric
Describe the first (initial) phase of acute renal failure
- Initial (onset)
- no clinical signs
- usually triggered by an ischemic event
- definable by a decrease in urine output or increase in creatinine
Describe the second (extension) phase of acute renal failure
- Extension
- continued hypoxia and inflammation, damaging to PT and LOH
- compromised Na/K pumps leads to cell swelling and death
- increased cytosolic calcium
- loss of brush border or apical and basal cell surfaces
Describe the third (maintenance) phase of acute renal failure
- Maintenance
- 1-3 weeks duration
- urine output may be increased or decreased
- urine is ultrafiltrate
Describe the fourth (recovery) phase of acute renal failure
- Recovery
- heralded by polyuria and extreme Na loss
- may take months
What are the risk factors for ARF?
dehydration hypovolemia anesthesia hypoxia SIRS
What is normal urine output?
What is considered abnormal?
1-2 ml/kg/hour
Abnormal
What is normal CVP?
0-10 cmH2O