Kidney 2 Flashcards
what typically causes hypernatremia?
free water loss (not sodium gain)
what can cause hypervolemic hypernatremia?
administration of hypertonic saline, or hypertonic bicarb
hypertonic dialysis, feedings
cushing’s syndrome
primary hyperaldosteronism
what can cause euvolemic hypernatremia (most common cause)
diabetes insipidus
hypodipsia
insensiible dermal and skin losses
what typically causes hyponatremia?
reduced ability to excrete free water due to
reduced GFR
reduced ECV
what can cause hyperosmolar hypernatremia?
hyperglycemia
what can cause euvolemic hyponatremia?
SIADH glucocorticoid deficiency hypothyroidism primary polydipsia poor osmolar intake (ex- beer drinkers) positive pressure ventilation
what can cause hypovolemic hypo-osmolar hyponatremia
reduced total ECF
reduced effective circulating volume
severe hypokalemia
To dx SIADH what needs to be normal?
kidney function
adrenal function
thyroid function
volume status
what conditions cause secondary renal sodium retention?
heart failure
liver dz
pregnancy
what conditions cause primary renal sodium retention?
Acute and chronic renal failure
Effective mineralocortical excess
Decreased oncotic pressure
Tubular syndromes
what can cause pseudohyperkalemia?
hemolysis
thrombocytosis
leukocytosis
what can cause redistribution hyperkalemia?
acidosis
decrease in insulin
beta-adrenergic blockage
what can cause hyperkalemia w/ GFR >20 and low aldosterone?
addison’s dz
hyporeninemic hypoaldosteronism
Drugs (PG syntheses inhibition, captopril)
where are the afferent sensors for circulating volume circulation?
lungs
what do catecholamines cause
sodium retention
what does ANP do?
causes excretion of Na
if a person is hyponatermic, what will their urine osmols usually be?
increased form serum
what can severe hyperlipidemia cause?
pseudohyponatremia
what are causes of SIADH?
CNS pathology
pulmonary
drug related
what are renal causes of volume depletion?
diuretics post-obstruction diuresis ATN (recovery) Rental tubular acidosis) salt-losing nephropathy
inability of kidney to handle a bicarbonate load?
renal tubular acidosis
what are extravascular sequestration causes of volume depletion?
intestinal obstruction
peritonitis
pancreatitis
rhabdomyolysis
What drugs can cause decreased renal excretion of K+ leading to hyperkalemia?
aldosterone antagonists (spironolactone)
ACEI, ARB
NSAIDs (prostaglandin inhibitors)
can you put someone who is experiencing hyperkalemia on an ACEI to an ARB?
No, will still have the same problem
What drugs can lead to hyperkalemia?
spironolactone triamterene amiloride captopril ACEIs and ARBs
if a patient is hypokalemic what must you assess?
metabolic status
renal excretion
what is one of the most common causes of a hypokalemic metabolic alkalosis
diuretics (thiazides)
if potassium urine is >20 mEq/L w/ hypokalemia where are is the likely problem?
kidney
what can cause metabolic acidosis w/ an increased anion gap?
renal failure acid overproduction meds (salicylates) DKA toxins (alcohol, ethylene glycol)
how do you determine the anion gap?
(Na+)- (Cl- + HCO3-)
what conditions are associated w/ a normal anion gap metabolic acidosis
extrarenal bicarb loss RTA (renal tubular acidosis) meds supplements aldosterone deficiency
what are common causes of metabolic alkalosis
gastric loss diuretics antacids (Tums) volume depletion Gitelman syndrome Bartter syndrome
a Na below what or above what is a medical emergency?
155
A potassium above what and below what is an emergency?
6.5
a pH below what and above what is a medical emergency?
7.55
Bicarb levels above what and below what are a medical emergency?
bicarb 40
are cultures usually done in females w/ their first UTI
no
what are features of cystitis?
Frequency Dysuria Urgency Suprapubic pain/discomfort Hematuria
what are the 2 important labs on dipstick for cystitis?
LCE and n itrite
LCE is more sensitive
what should you see on the microscope analysis of urine w/ cystitis?
WBCs
RBCs
what are cultures used for in cystitis?
to ID organism
use after failure of response
what are common causes of hematuria?
UTI
stones
cancer
BPH
what is the highest hazard ratio w/ cystitis for premenopausal women?
frequency of intercourse
what is the highest risk for cystitis in postmenopausal women?
h/o of 6 or more UTIs
insulin treated DM
who can experience complicated cystitis?
pregnant very young or old diabetic immunocomprimised GU abnormalities recent abx therapy obstruction
what are the 5 main features of pyelonephritis?
fever >38 degrees Celcius flank pain CVA tenderness Naseau Vomiting
what commonly causes pyelonephritis?
E. Coli (will be nitrite positive)
on US what can you see w/ pyelonephritis
focal bacterial infection on a pole of the kidney
what do clotting red blood cells indicate?
urological problem, occurring in the lower urinary tract
stones, tumor
if bleeding is occurring in the upper urinary tract will there be clotting?
No, most of those enzymes are removed
red cell casts are associated with what?
glomerulonephritis
what is the most effective tx for cystitis?
bactrim for 3 days (160-800 mg BID)
what are other treatment for cystitis?
ciprofloxacin
levofloxain
nitrofurantoin
trimethoprim by itself (recurrent)
why is increasing fluids w/ cystitis controversial
too much fluid may dilute the abx
what is the benefit of cranberry juice w/ cystitis?
appear to prevent bacterial adherence to urinary tract epithelium
have no abx activity
what changes the pH of urine and can help prevent UTIs
vitamin C 500 mg at bedtime
what is a recurrent UTI?
3 infections per year of >2 within 6 months
culture negative at 2 wk post treatment
what do you use for tx of pyelonephritis?
ceftriaxone IV
ciprofloxacin PO or IV
levofloxacin PO
TMP-SMX PO
Does urine production exclude urinary obstruction w/ pyelonephritis?
No
what should you get if you think a patient has an obstruction or stone w/ pyelonephritis?
Renal US
when can you convert a person w/ pyelonephritis to an oral regimen?
If afebrile for 12-24 hours
what are some risk factors for stones?
hypercalciuria low urine output high protein diet high salt diet high oxalate diet
what is the most frequent cause of renal stones?
calcium oxalate/ phos
opaque, can see on x-ray
what causes staghorn calculus?
magnesium NH4/ PO4
can see on x-ray, opaque
which of the stones may be loosened and you can’t see on an x-ray
uric acid
what crystals look like coffin-lids?
phosphate crystals
what is a KUB
kidney, ureters, and bladder x-ray (flat plate)
how do you get rid of staghorn calculi?
surgery
what are the main features of renal cell carcinoma (from most to least common)
hematuria
abdominal mass
pain
what other symptoms are associated w/ renal cell carcinoma?
weight loss
anemia (but may see polycythemia because some can produce EPO)
fever
what are causes of urinary tract obstructions?
Congenital urinary tact malformation
Intraluminal obstruction
Extrinsic compression
Acquired anomalies
if urine osmols are higher than serum osmols then what is there?
increased circulating levels of ADH
