Nep Flashcards
(233 cards)
1
Q
_____ is defined as a rapid rise in blood urea nitrogen (BUN) or creatinine over a period of several hours to days
A
Acute renal failure (ARF), or better referred to as acute kidney injury (AKI),
2
Q
_____ can be used interchangeably with the term renal insufficiency; literally,
azotemia means the buildup of azole groups or nitrogen in the blood.
A
Azotemia
3
Q
____describes a syndrome of very severe renal failure in which there is the need for
dialysis to save life
A
Uremia
4
Q
T or F
A
Uremia does not necessarily mean the same thing as chronic renal failure
5
Q
AKI
____means decreased perfusion of the kidney.
_____ means decreased drainage from the kidney or decreased forward flow of urine.
____means there is a tubular or glomerular problem, and the kidney itself is defective.
A
Prerenal azotemia
Postrenal azotemia
Intrarenal
6
Q
The BUN can be falsely low when there is ______
A
liver disease, malnutrition, or SIADH.
7
Q
______ is our closest approximation of glomerular filtration rate (GFR) without the use of more cumbersome testing such as the clearance of inulin.
A
Creatinine clearance
8
Q
Causes of pre-renal azotemia
A
- hypovolemia on any basis (dehydration, burns, poor oral intake, diuretic, vomiting, diarrhea, sweating, hemorrhage),
- hypotension on any basis (septic shock, cardiogenic shock, anaphylactic shock),
- third spacing of fluids such as peritonitis, osmotic diuresis,
- low aldosterone states such as Addison disease.
9
Q
The first clue to the diagnosis of prerenal azotemia is a ______
A
BUN:creatinine ratio of 20:1.
10
Q
Pre-renal azotemia
There is also a low _______
This results in a very high ______
A
urine sodium and low fractional excretion of sodium (FeNa <1%).
urine osmolality as well.
11
Q
Pre-renal azotemia
Concentrated urine has a_____ and ______
A
high specific gravity (>1.010) and
a high urine osmolality (>500).
12
Q
T or F
Low albumin states also lead to decreased renal perfusion
A
T
13
Q
Pre-renal Azotemia
There is markedly diminished renal perfusion because of the obstruction in the renal artery.
A
Renal artery stenosis
14
Q
Renal artery stenosis
This effect is greatly exaggerated with the use of ____which markedly diminish renal perfusio n
A
ACE inhibitors,
15
Q
Pre-renal Azotemia
______ is renal failure based entirely on the presence of hepatic failure. The kidneys are normal. The etiology of the rise in BUN and creatinine is thought to be from
an intense vasoconstriction of the afferent arteriole, resulting in decreased renal perfusion
A
Hepatorenal syndrome
16
Q
______is diagnostic of hepatorenal syndrome
A
No improvement in renal failure after 1.5 L of colloid,
like albumin,
17
Q
HRS
____ and ____may be beneficial in hepatorenal syndrome. However, the best treatment is liver transplantation.
A
Midodrine,
an alpha agonist, and octreotide
18
Q
ACE inhibitor–induced renal failure is from
A
vasodilation of the efferent arteriole
19
Q
Despite the ability of ACE inhibitors to potentially worsen renal function, the overall effect on the kidney is _____
A
diminishing the rate of progression to uremia and renal failure
20
Q
ACE inhibitors and angiotensin receptor blockers decrease ______
A
hypertension inside the glomerulus.
21
Q
ACE inhibitors decrease proteinuria by_____
A
35–45%.
22
Q
Creatinine will only begin to rise when you have lost at least_____
A
70–80% of renal function.
23
Q
BUN Crea ration early and late post renal azotemia
A
Initially, the BUN and creatinine will elevate in a ratio of 20:1 as it does with prerenal azotemia.
then the BUN:creatinine ratio will lower to closer to
10:1, such as that seen in acute tubular necrosis (ATN).
24
Q
About 85% of acute renal failure is secondary to _____
A
intrinsic renal disease such as ATN.
25
Three Phases of intrinsic renal failure (Not Seen in All Patients)
• ________—This is the time between the acute injury and the onset of renal failure.
• ________(<400 mL per 24 hours) or anuric (<100 mL per 24 hours)
•_____—This is a diuretic phase when all the water not previously excreted will now leave the body in a vigorous polyuria.
Prodromal
Oliguric
Postoliguric
26
Intrinsic renal failure
The initial clue is a BUN:creatinine ratio close to____
10:1.
27
Further clues to the diagnosis of ATN are a
1
2
3
high urine sodium (>40),
high fractional excretion of sodium (>1%),
and low urine osmolality (<350).
28
Diagnosis:
Urine osmolarity: >500
Urine Na+: <20
FeNa+: <1%
Urine sediment: Scant
Pre-renal azotemia
29
Diagnosis:
Urine osmolarity: <350
Urine Na+: >40
FeNa+:>1%
Urine sediment: Full (brownish pigmented
granular casts, epithelial casts)
ATN
30
T or F
Diuretics such as furosemide or mannitol do not reverse the ATN
T
31
T or F
Hydration can prevent contrast-induced renal failure, but it does not reverse it once it occurs
T
32
ATN
Another form of ineffective therapy is ____ at low dose to increase renal perfusion
dopamine
33
_____ accounts for 10–15% of intrinsic renal failure. It can be distinguished from other causes of renal failure by the presence of fever and rash on physical
examination and many WBCs, occasionally eosinophils.
Allergic interstitial nephritis (AIN)
34
Meds causing AIN
can be from penicillins, cephalosporins,
| sulfa drugs, allopurinol, rifampin, and quinolones
35
It is important to remember that any sulfa drug can cause allergic reactions. Besides antibiotics, other examples of sulfa drugs are diuretics such as ________
thiazides, furosemide, or acetazolamide.
36
The most common infections to result in AIN are ______
leptospirosis, legionella, CMV, rickettsia, and streptococci.
37
____ is present in 80% of those with AIN.
_____ is present in 25–50% of patients
Fever
Rash
38
The best initial test for AIN is a ______
urinalysis (UA) looking for white cells.
39
The most accurate test for urine eosinophils is a ______
Hansel stain or Wright stain of the urine
40
Massive hemoglobinuria severe enough to cause renal failure is generally only caused by an ______
ABO
| incompatibility
41
The most important test when there has been a severe crush injury or seizure and the rhabdomyolysis is potentially life threatening is an ______
EKG or potassium level
42
The best initial test that is specific for rhabdomyolysis is a _____
UA in which you find a dipstick that is positive for blood but in which no red cells are seen
43
Rhabdomyolysis is confirmed with a markedly elevated _____
serum CPK level
44
CPK
In order for nephrotoxicity to occur, the level must be enormously elevated into the _____ range with a normal value generally <500 or less.
10,000 to 100,000
45
Rhabdomyolysis
If there are EKG abnormalities from the hyperkalemia the best initial therapy is ______
calcium chloride or gluconate
46
Rhabdomyolysis
_____ may help prevent the precipitation of the pigment in the tubule
Alkalinizing the urine with bicarbonate
47
_____ proteins, such as in myeloma, also cause tubular damage.
Bence-Jones
48
____ is most prominently a cause of nephritic syndrome, however, not tubular damage
Myeloma
49
The most common cause of hyperoxaluria resulting in acute renal failure is from_____ in a suicidal person who ingests antifreeze
ethylene glycol overdose
50
ethylene glycol overdose
The diagnosis is confirmed by finding _____
oxalate crystals on a UA. Oxalate crystals are shaped like envelopes
51
Acute ethylene glycol overdose is treated with _____ to prevent the formation of the toxic metabolite of ethylene glycol, which is oxalic acid.
fomepizole infusion
52
Chronic hyperoxaluria and kidney stones can be caused by _____
Crohn’s disease because of fat and
| calcium malabsorption.
53
What is given to prevent uric acid nephropathy. in pts with tumor lysis syndrome
Allopurinol treatment with alkalinization of urine markedly reduces the risk of uric acid nephropathy
54
Calcium precipitates in the kidney tubule, forming stones. In addition, hypercalcemia can lead ________ and ____
to distal RTA and nephrogenic diabetes insipidus
55
The most common cause of hypercalcemia is_____
primary hyperparathyroidism.
56
The most common toxins to be associated with renal insufficiency and ATN are_____
NSAIDs, aminoglycosides, cephalosporins, contrast agents, amphotericin, chemotherapy such as cisplatin,
radiation effect, heavy metals such as lead, mercury, or gold, and cyclosporine
57
The difference between the basis of allergic interstitial nephritis and direct toxins is that allergic nephritis
_______
occurs with the first dose and is associated with fever, rash, joint pain, and eosinophils in both
blood and urine.
58
______is the least nephrotoxic compared with gentamicin and amikacin.
Tobramycin
59
_____ generally takes 5–10 days of administration to result in toxicity
Aminoglycoside toxicity
60
Renal failure due to aminoglycosides is
| frequently _______
non-oliguric (K+ levels not elevated)
61
The ability of antibiotics to kill bacteria is associated with
the peak level, but the likelihood of toxicity is associated with the _______
trough level
62
Aminoglycoside-related nephrotoxicity is estimated to
| be between _____ of all drug-induced nephrotoxicity and is usually reversible.
10–20%
63
This medication is associated with renal insufficiency as well as distal renal tubular acidosis.
Amphotericin B.
64
Labs of Amphotericin B toxicity
It is expected that after several days or weeks of amphotericin use, the patient will develop a high creatinine as well as a decreased magnesium, bicarbonate, and potassiumlevel.
65
What is the possible etiology?
patient who undergoes a vascular catheter procedure such as angioplasty who develops renal failure several days later
Atheroembolic Disease
66
The BUN and creatinine may be up in a 20:1 ratio, such as in prerenal azotemia, because the
hypertonicity of the agent provokes an intense vasospasm of the afferent arteriol
Radiocontrast material for CT scanning
67
____ is associated with renal failure in addition to its toxicity on the pancreas
Pentamidine
68
____is a protease inhibitor that results in renal failure usually from the drug precipitating out in the kidney tubules
Indinavir
69
NSAIDs are a frequent cause of renal failure. NSAIDS cause renal failure by several mechanisms:
* Interstitial nephritis
* Direct toxic effect on the tubules
* Papillary necrosis
* Inhibition of vasodilatory prostaglandins in the afferent arteriole
* Membranous glomerulonephritis
70
_____occurs in patients with a history of sickle cell disease, diabetes, urinary obstruction, or chronic pyelonephritis
Acute papillary necrosis
71
Acute papillary necrosis SSx
The presentation is with the sudden onset of flank pain, hematuria, pyuria, and fever.
72
The most accurate diagnostic test for papillary necrosis
| is a_____
CT scan. The CT scan will show “bumpy” contours in the renal pelvis where the papillae have sloughed off.
73
In those patients with significant underlying renal disease who have an unavoidable radiologic procedure requiring contrast, you must ____
hydrate with 1–2 liters of normal saline over 12
| hours before the procedure
74
______have also been shown to decrease the risk of renal failure in CIN
Bicarbonate and N-acetyl cysteine
75
___ and ______ cause glomerular disease and are certainly the most common causes of nephrotic syndrome and end stage renal disease
Diabetes and hypertension
76
All forms of GN can be characterized by _____
edema, hematuria, red cell casts, and hypertension
77
The edema of GN is found first in areas of low tissue tension, such as the______
periorbital area or the scrotum
78
The most important distinction between GN and nephrotic syndrome is_____
the degree of proteinuria.
79
GN is also characterized by modest amounts of protein in the urine with the daily total being _____ per 24 hours, although by definition nephrotic syndrome does not begin until there are ____ grams per 24 hours
<2 grams
>3.5
80
However, the single most important test
| to diagnose GN is the______
renal biopsy
81
Causes of Glomerulonephritis Disease Spectrum
Vascular disease
```
Wegener granulomatosis
Churg-Strauss syndrome
Henoch-Schönlein purpura
Polyarteritis nodosa
Thrombotic thrombocytopenic purpura (TTP)
Hemolytic uremic syndrome (HUS)
Cryoglobulinemia
```
82
Causes of Glomerulonephritis Disease Spectrum
| Glomerular Disease
```
Goodpasture syndrome
Postinfectious glomerulonephritis
Henoch-Schönlein purpura
SLE
Idiopathic rapidly progressive glomerulonephritis
Alport syndrome
Diabetes and hypertension (most common causes)
Amyloid
```
83
______ is characterized by systemic vasculitis that most often involves the kidney, lung, and upper respiratory tract such as the sinuses or middle ear
Wegener granulomatosis (WG)
84
Laboratory abnormalities in WG are _____
elevated ESR, anemia, and leukocytosis. Rheumatoid factor is positive in 50%.
85
The best initial test that is specific for WG is the ____
anti-proteinase-3 antibody, which is also known as cytoplasmic antineutrophil cytoplasmic antibody, or C-ANCA.
86
The most accurate test for WG is a_____
biopsy of the kidney, nasal septum, or lung looking for
| granulomas
87
______ characterized by a history of asthma, eosinophilia, and other atopic diseases. The characteristic diagnostic tests are the elevated eosinophil count and positive P-ANCA or antimyeloperoxidase
Churg-Strauss Syndrome
88
Churg-Strauss Syndrome
The most accurate test is a______ showing the granulomas and eosinophils.
Treatment is with _______
lung biopsy
glucocorticoids and cyclophosphamide.
89
______ is an idiopathic disorder of renal and lung disease characterized by a unique antibasement membrane antibody
Goodpasture syndrome (GP)
90
Unlike Wegener or Churg-Strauss, GP does not affect multiple organs or sites in the body besides the____
lung and the kidney
91
Goodpasture syndrome (GP)
The best initial test to confirm the diagnosis is the____
level of
| antibasement membrane antibodies to type IV collagen
92
Goodpasture syndrome (GP)
The single most accurate test is a
lung or kidney biopsy.
93
Goodpasture syndrome (GP)
The biopsy shows _____
linear deposits on immunofluorescence
94
______is a systemic vasculitis of small- and medium-sized arteries that affects virtually every organ in the body with the exception of the lung
Polyarteritis nodosa (PAN)
95
PAN
The most accurate diagnostic test is a____, and treatment is with _____
biopsy
cyclophosphamide
and steroids.
96
_____ presents with mild hematuria that resolves spontaneously in 30% of patients. About 40–50% of patients progress to end stage renal disease
IgA nephropathy
97
How to distinguish psgn from IgA nephropathy
This is to distinguish it from poststreptococcal
| glomerulonephritis, in which the renal involvement occurs 1–2 weeks later or longer
98
The treatment of IgA nephropathy is difficult. There is no proven effective therapy. Anyone with proteinuria should receive______
ACE inhibitors or angiotensin receptor blockers (ARB).
99
In addition to group ______ numerous other
| infections can be associated with postinfectious glomerulonephritis.
A beta hemolytic streptococci (Streptococcus pyogenes),
100
The best initial test for PSGN is
```
the antistreptolysin (ASO) test and the antihyaluronic acid
(AHT) test.
```
101
The most accurate test for PSGN is the _____
renal
| biopsy showing “humps” on electron microscopy.
102
Renal disease from _____ is associated with chronic hepatitis C or less commonly B.
cryoglobulinemia
103
Besides the renal disease, cryoglobulinemia is associated with ________
joint pain, neuropathy, and purpuric skin lesions
104
Cryoglobulinemia is associated with an elevated
| _____and low levels of ____ and is confirmed with a test for the cryoglobulins
ESR
complement
105
The incidence of glomerular involvement in diabetes is directly proportional to the ____
duration of the diabetes
106
What dse?
Double-stranded DNA levels go up and complement levels go down as a marker of severity in flare-ups of the disease.
SLE
107
Tx of SLE with Proliferative disease:
Use steroids combined with mycophenolate. Mycophenolate is superior to cyclophosphamide.
108
_____ is the combination of glomerular disease with congenital eye and ear abnormalities. There is sensorineural hearing loss
Alport syndrome
109
What type of amyloidosis
Plasma cell dyscrasia causing deposition of protein derived from immunoglobulin
light chains. This may be associated with multiple myeloma
110
Amyloidosis
Other unique methods of diagnosis are_____
aspirating the abdominal fat pad or taking a sample of
| the rectum
111
AMyloidosis
___ and _____can control protein
production.
Melphalan and prednisone
112
Nephrotic syndrome is defined as the presence of renal disease sufficient to produce
a level of proteinuria >3.5 grams per 24 hours, hyperlipidemia,
edema, and a
low serum albumin level
113
Why is there hyperlipidemia in NS
Hyperlipidemia is of unclear etiology but is most
likely from the loss of the lipoprotein markers or signals on the surface of chylomicrons and LDL that lead to the clearance of these lipids from the bloodstream
114
NS
Hypercoagulable states or thrombophilia develops from the _____
urinary loss of natural anticoagulant
| proteins such as antithrombin, protein C, and protein S
115
NS
If steroids do not work, the next best step in therapy is to add______
cyclophosphamide
| or mycophenolate
116
______is the most common cause of nephrotic syndrome in adults.
FSGS
117
____ Associated with the use of heroin as well as
| HIV. Limited response (only 20–40%) to steroids
Focal-Segmental Glomerulosclerosis (FSGS).
118
FSGS May progress to end stage renal disease
| (ESRD) over_____
5–10 years.
119
What kind of NS
______Associated with cancer such as lymphoma or breast cancer, and infections such
as endocarditis or chronic hepatitis B or C. Other etiologies are lupus, penicillamine, gold
salts, and NSAIDs
Membranous.
120
What kind of NS
Most common form in children, although it may
account for 15% of adult disease. NSAIDs have also been associated with nil lesion disease
Nil Lesion (Minimal Change Disease).
121
EM findings of MCD
Light microscopy is normal and electron microscopy is needed to see fusion of foot processes
122
Associations of MCD
Hodgkin’s lymphoma has an association with nil
| lesion disease.
123
What NS
Mostly idiopathic, steroid-resistant type of nephrotic syndrome. Immunofluorescent
staining shows IgM deposits in an expanded mesangium
Mesangial.
124
What NS
____Associated with chronic hepatitis and low serum complement levels
Membranoproliferative.
125
____ and ____ are also useful therapeutically. for Membranoproliferative NS
Dipyridamole and aspirin
126
Proteinuria suggestive of problems in?
This can be from either glomerular or tubular diseases, although glomerular diseases can give greater amounts
127
Proteinuria is also caused by prolonged standing,
| which is known as ______
orthostatic proteinuria.
128
Nitrites. _________educe nitrate to nitrite, which is a marker of infection
Gram-negative bacteria r
129
By itself, the isolated finding of bacteria in the urine is of very limited significance. The most important exception is in ______ whom you should screen for bacteria
and treat.
pregnant women,
130
What kind of cast?
Asstd with Dehydration. These casts develop as an accumulation of the normal amount of tubular protein. They do not necessarily mean disease.
Hyaline
131
What kind of cast?
Asstd with Glomerulonephritis
Red cell
132
What kind of cast?
Asstd with Chronic renal failure
Broad, waxy
133
What kind of cast?
Also called “dirty” or “muddy.” They are associated with acute tubular necrosis and represent accumulated epithelial cells
Granular
134
What kind of cast?
Asstd with Pyelonephritis, interstitial nephritis
White cell
135
The most common causes of end stage renal disease (ESRD) that require dialysis are __ and ____
diabetes
| and hypertension
136
The anemia of ESRD is ____ and _____
normochromic and normocytic
137
Cause of Hypocalcemia/Hyperphosphatemia in ESRD
This is from the loss of 1,25-dihydroxyvitamin D production
138
IN ESRD
High phosphate levels contribute to low
calcium levels by _____
precipitating out in tissues in combination with the calcium.
139
Tx of High phosphate levels in ESRD
treated with phosphate binders, such as calcium carbonate or calcium acetate
140
_____ is a substance that simulates the effect of calcium on the parathyroid. It is used in severe, refractory cases
Cinacalcet
141
MOA of Cinacalcet
Cinacalcet will tell the parathyroid to shut off
| parathyroid hormone production and helps decrease phosphate in this way
142
In ESRD
_____containing phosphate binders should not be used. It is associated both with CNS accumulation and dementia as well as bone abnormalities.
Aluminum-
143
This is also known as osteitis fibrosa cystica. Bone abnormalities occur because dead kidneys don’t make 1,25 vitamin D. This leads to a low calcium level
Osteodystrophy
144
The reason for this is not precisely clear, however, this is the most common cause of death for those on dialysis.
Hypertension and Accelerated Atherosclerosis
145
This is the second most common cause of death in dialysis patients.
Infection.
146
MCC of infxn in ERSD
The most common organism is Staphylococcus because of
the constant need to penetrate the skin to place someone on dialysis for 4–6 hours 3–4 times
a week.
147
Although nephrotic syndrome gives thrombophilia because of the urinary loss of ______ the most common coagulation problem with ESRD is
bleeding
protein C, protein S, and antithrombin,
148
Reason of inc bleeding in ESRD
This is because of uremia-induced platelet dysfunction
149
Uremia-induced bleeding is treated with ____which releases subendothelial stores of von Willebrand factor and factor VIII, which increase platelet aggregation and
adherence.
desmopressin,
150
Duration of Survival
Live related donor _______
Cadaver donor _______
Dialysis alone _____
Diabetics on dialysis ____
95% at 1 year, 72% at 5 years
88% at 1 year, 58% at 5 years
30–40% at 5 years
20% at 5 years
151
Cause iof hyponatremia from ESRD
This generally occurs from either increased free water retention or urinary sodium loss. About
85–90% of sodium is extracellular
152
An acute 15–20 point drop in sodium level can result in a ____
seizure or coma
153
Moderate hyponatremia can be managed with ____
normal saline administration combined with a
| loop diuretic such as furosemide
154
Severe and chronic hyponatremia such as that resulting in seizure or coma should be managed with ____
3% hypertonic saline or the V2 receptor-antagonists conivaptan and tolvaptan
155
These are conditions in which the total body sodium level is truly normal and the sodium blood level is artificially low. Treatment is directed at etiology of the lab
artifact, not specifically the sodium level
Pseudohyponatremia.
156
The sodium level is decreased by ____for every 100 mg/dL increase in glucose above normal
1.6 mEq/L
157
How does hyperglycemia cause Pseudohyponatremia
The high glucose load causes a transcellular shift of
water out of the cell into the vascular space unaccompanied by sodium. This drops the
serum sodium level. Mannitol and sorbitol can do the same
158
Hypervolemic States (Increased ECF). These are all conditions in which there is a decrease in intravascular volume resulting in an increase in ADH secretion from the posterior pituitary. This is a form of appropriate increased ADH syndrome
* CHF
* Nephrotic syndrome and low albumin states
* Cirrhosis
* Renal insufficiency:
159
Hypovolemic States (Decreased ECF). For most of these, the hyponatremia develops because_____
of the loss of sodium through body fluids and replacement with free water
160
Urine Na <20 causes
Dehydration
Vomiting
Diarrhea
Sweating
161
Urine Na >20
```
Diuretics
ACE inhibitors
Renal salt wasting
Addison disease
Cerebral sodium wasting
```
162
Causes of hyponatremia with euvolumic states
* Psychogenic polydipsia
* Hypothyroidism: mechanism unknown
* Diuretics: can be both hypovolemic and euvolemic
* ACE inhibitors: probably through an increase in ADH
* Endurance exercise
* Syndrome of inappropriate secretion of ADH (SIADH)
163
Meds causing SIADH
* SSRIs
* Tricyclic antidepressants
* Haloperidol
* Cyclophosphamide
* Vincristine
* Carbamazepine
* Thiazide diuretics
164
If urine osmolality is >100 in the presence of hyponatremia, the person most likely has_____
SIADH
165
Treatment of SIADH is to _____for mild disease and give _____ for severe disease as was previously described.
restrict fluids
hypertonic saline
166
For chronic disease in which the underlying cause of the SIADH cannot be corrected, therapy with ______.
These medications inhibit the effect of ADH on the kidney tubule and lead to water diuresis.
conivaptan, tolvaptan, or demeclocycline is used
167
Conivaptan and tolvaptan are ______-antagonists
V2 receptor
168
Demeclocycline and lithium treat SIADH by inducing _____
nephrogenic diabetes insipidus.
169
Presentation of hypernatremia
Insensible losses
GI loss:
Transcellular shift:
Renal
170
Acute hypernatremia is treated with ______
isotonic fluids intravenously
171
Watching for a decrease in urine volume after administering_______ distinguishes CDI from NDI.
ADH
172
Mx of CDI.
1. Correct the underlying cause, if possible.
2. ______
Vasopressin (ADH). It can be given subcutaneously, intravenously, intramuscularly, or by nasal spray (all routes except oral).
173
Mechanism of trancellular shift causing hypo K
Increased entry into cells (transcellular shift) can be from alkalosis, increased levels of insulin, beta adrenergic activity, and the replacement of vitamin B12 in B12-deficient patients.
Trauma patients have increased beta adrenergic activity, that may lead to hypokalemia
174
effect of Mg on K levels
Low magnesium levels. Magnesium decreases urinary loss of potassium. When you are deficient in magnesium, you start to spill potassium into the urine.
175
Most impt dxtic in hypoK
In emergency cases, the most important diagnostic test is the EKG.
176
EKG findings for Hypo K
EKG abnormalities include T-wave flattening and U-waves.
177
____ is an extra wave after the T-wave that is indicative of Purkinje fiber repolarization.
U-wave
178
Why not to use dextrose containing fluids in K correction
Dextrose will provide the shift of potassium into the cells and will further lower potassium levels.
179
Mechanisms of transcellular shift causing hyperK
_______—secondary hemolysis, mechanical trauma during venipuncture, platelet count >1,000,000 (106), WBC count >100,000 (105)
_______—secondary cellular buffering (H+ moves into cells, K+ moves out)
–– Pseudohyperkalemia
–– Acidosis
180
Hyper K from decreased urinary excretion
```
–– Renal failure
––______: ACE inhibitors, type IV RTA, adrenal enzyme deficiency; heparin inhibits production of aldosterone
–– _________ or adrenalectomy
–– Potassium-sparing diuretics—_____
–– NSAIDs
```
Hypoaldosteronism
Primary adrenal insufficiency (Addison disease)
amiloride, spironolactone
181
Tx of HyperK
* ______—membrane stabilization (most emergent treatment in presence of EKG abnormalities). Effect is immediate and short lived.
* _______—alkalosis drives K+ into cells. Do not give in same IV line as calcium. Forms CaCO3 precipitates.
* _______—drives K+ intracellular, takes 30–60 minutes to work
Calcium chloride
Sodium bicarbonate
Glucose and insulin
182
Tx of hyper K
1
2
3
* Diuretics, beta agonists
* Cation exchange resin (Kayexalate)
* Dialysis
183
For every ____ increase in the level of serum bicarbonate, there is a______point increase in the
pCO2
1-point
0.7-
184
Volume contraction of dehydration results in an increased level of _____, which leads to ______
aldosterone
metabolic alkalosis
185
Increased levels of aldosterone in volume contraction lead to increased levels of ______) excretion.
hydrogen ion (H+
186
Causes of alkalosis from H loss
* Exogenous steroids
* GI loss (vomiting, nasogastric suction)
* Renal loss (Conn syndrome, Cushing, ACTH overproduction, licorice, Bartter syndrome)
* Decreased chloride intake
* Diuretics
187
Causes of alkalosis from HCO3 retention
Bicarbonate administration
• Contraction alkalosis
• Milk-alkali syndrome
188
How to compute anion gap
Anion gap = (Na+) – (HCO3 –) + Cl–)
| normal: 8–12
189
Causes of low anion gap Metabolic Acidosis (MAC)
* Myeloma
* Low albumin level
* Lithium
190
The anion gap is a gauge of the ______ in the bloodstream
unmeasured anions
191
The majority of the unmeasured anions are usually ____which has a significant amount of negative charge
albumin,
192
In addition to albumin, which is normal, the other anionic substances are______
lactate, ketoacids, and the metabolic end products of toxic alcohols
193
Na+ and cations = ______
HCO3 – and Cl– and anions
194
Causes of NAGMA
* Diarrhea
* Renal tubular acidosis
* Ureterosigmoidostomy
195
Causes of HAGMA
LA MUD PIE (Mnemonic)
Lactate (sepsis, ischemia, etc.)
Aspirin
Methanol
Uremia
Diabetic ketoacidosis (DKA)—Beta hydroxybutyric acid (BHB) and acetoacetate, which are
formed from fatty acids, are an alternate fuel source because the cells cannot absorb glucose
because there is a deficiency of insulin
Paraldehyde, Propylene glycol
Isopropyl alcohol, INH
Ethylene glycol (antifreeze, low calcium)
196
Causes of distal RTA (type 1)
* Usually sporadic
* Also secondary to autoimmune disease (e.g., Sjögren syndrome, SLE)
* Drugs—
* Nephrocalcinosis, sickle cell, chronic infection
* Familial
* Chronic hepatitis
197
Drugs causing distal RTA
amphotericin, lithium, analgesics, iphosphamide
198
SSx of distal RTA
* Inability to develop a high H+ concentration in urine. Urine pH is >5.3.
* Secondary hyperaldosteronism and hypokalemia
* Nephrocalcinosis and nephrolithiasis
199
Acid load test; give ammonium chloride, which should lower urine pH secondary to increased H+ formation. With type I RTA, ________
the urine pH remains elevated. Serum bicarbonate
| = 10.
200
MOA of hypoK in pts with distal RTA
Patients with distal RTA develop hypokalemia because patients lose the ability to secrete
hydrogen ions or H+. Instead of excreting H+, the kidney will excrete K+.
201
TX of distal RTA
Oral bicarbonate is the treatment because bicarbonate reabsorption in the proximal tubule still works.
Also, potassium replacement; potassium citrate will replace both bicarbonate as well as potassium in distal RTA.
Further, citrate is an effective calcium stone antagonist
202
Etiology of Proximal RTA
Fanconi syndrome, Wilson disease, amyloidosis, myeloma, acetazolamide, vitamin D deficiency, secondary hyperparathyroidism, chronic hypocalcemia, heavy metals, chronic hepatitis, autoimmune diseases such as SLE and Sjögren syndrome
203
Etiology of Proximal RTA
Inability to absorb bicarbonate. The initial urine pH is basic (until the body loses enough bicarbonate that it is within the range of absorption of the distal tubule), then
the urine will become acidic (pH <5.4).
204
Patients with type II get_____ whereas type I get
| _______ Both get hypokalemia
bone lesions (osteomalacia and rickets),
kidney stones.
205
Dx of Prox RTA
Patients are unable to absorb bicarbonate loading (sodium bicarb IV) and have a basic urine in the presence of acidemia.
206
Normal response to bicarbonate loading
Normal individuals do not excrete bicarbonate in
| their urine until serum bicarbonate is >24
207
Tx of Prox RTA
Give potassium; mild volume depletion will enhance proximal bicarbonate reabsorption (a type of contraction alkalosis).
Thiazide diuretics and very large amounts of bicarbonates
are used.
208
Hyporeninemic/Hypoaldosteronism (Type IV) causes
```
• An aldosterone deficiency of any cause or adrenal insensitivity to angiotensin II, which
normally stimulates aldosterone release
• Diabetes (50%)
• Addison disease
• Sickle cell disease
• Renal insufficiency
```
209
SSx of Hyporeninemic/Hypoaldosteronism (Type IV) causes
Presence of high urine sodium with oral salt restriction establishes the diagnosis.
210
TX of Hyporeninemic/Hypoaldosteronism (Type IV)
Treatment. Administration of fludrocortisone
211
MOA of fludrocortisone
Fludrocortisone has a high degree of mineralocorticoid
| effect and is similar to administering aldosterone.
212
Etiology of hypercalcuria
Increased absorption
Idiopathic renal hypercalciuria
Resorptive
213
hypercalcuria from Increased absorption causes
–– Vitamin D intoxication
–– Increased vitamin D with sarcoid and other granulomatous disease
–– Familial
214
hypercalcuria from inc Resorptive causes
–– Hyperparathyroidism (10–30% of patients present with stones)
–– Multiple myeloma, metastatic disease to bone, hypercalcemia of malignancy
215
Causes of Hyperoxaluria
* Primary familial
| * Enteric
216
UTI causing stones
Urinary infection with urease-producing organisms such as Proteus, Staphylococcus, Pseudomonas, and Klebsiella give a highly alkaline urine that produces struvite stones
217
Dx of stones
* __________—high-yield test and most cost-effective
* ________—no contrast needed for stones; contrast is to identify masses, abscesses, and tumors; high-yield test
U/S
Helical (spiral) CT scan
218
TX of nephrolithias
• Shockwave lithotripsy for stones <2 cm. Unfortunately, the fragments may cause
obstruction themselves.
• Ureteroscopy
• Percutaneous removal (requires more anesthesia and hospital stay)
219
Adult Polycystic Kidney Disease
Extra-renal manifestations
```
–– Hepatic cysts (40–60%)
–– Colonic diverticula
–– Hypertension (50%)
–– Intracranial aneurysm (10–20%)—other vascular aneurysms may be seen
–– Mitral valve prolapse (25%)
```
220
This is due to atherosclerotic disease in elderly persons and fibromuscular dysplasia in young women.
Renal Artery Stenosis
221
Renal Artery Stenosis SSx
The key feature is an upper abdominal bruit radiating laterally, which is present
in 50–70% of patients
222
RAS
The best initial screening test is the _____
abdominal U/S.
223
The______ is a test that measures the uptake of a radioisotope before and after the administration of captopril. A positive test is when there is decreased uptake of the isotope (i.e., decreased GFR) after giving the
captopril
captopril renogram
224
RAS
The ______ is still the best method of confirming the diagnosis
arteriogram
225
Best initial Tx of RAS
The best initial treatment is percutaneous transluminal angioplasty. If stenosis recurs, then the procedure should be repeated. If angioplasty fails, surgical resection is
attempted
226
This is most commonly due to a unilateral adenoma. Adenomas can also be bilateral. The rest of the cases are from bilateral hyperplasia
Primary Hyperaldosteronism (Conn Syndrome
227
SSx of Conn syndrome
Hypertension in association with hypokalemia found on routine screening tests or
• Symptoms of hypokalemia such as muscular weakness and polyuria and/or polydipsia from a nephrogenic diabetes insipidus
228
Dx of Conn
Elevated aldosterone levels in urine and blood.
229
Tx of Conn
Surgical resection in those with an adenoma. Potassium-sparing diuretics such as spironolactone in those with hyperplasia
230
The key feature is episodic hypertension in association with headaches, sweating, palpitations, and tachycardia. Pallor or flushing may also occur.
Pheochromocytoma
231
The best initial tests are
urinary vanillylmandelic acid (VMA), metanephines, and
| free urinary catecholamines
232
The key feature is hypertension in association with characteristic cushingoid manifestations such as truncal obesity, buffalo hump, menstrual abnormalities, striae and
impaired healing, etc.
Cushing Disease
233
Dx of Cushings
Dexamethasone suppression testing and 24-hour urine cortisol are the best initial tests.
