first aid topics Flashcards
distal renal tubular acidosis type 1 - defect
inability of alpha intercalated cells to secrete H +, so no new bicarb is generated and leads to metabolic acidosis
distal RTA - urine pH
basic, >5.5
serum K in distal RTA
decreased, hypokalemia
causes of distal RTA type 1
amphotericin B, analgesic nephropathy, congenital anomalies, obstruction of urinary tract, autoimmune diseases (SLE)
associations with distal RTA
increased risk for calcium phosphate kidney stones (due to increased urine pH and increased bone turnover related to buffering)
stones are associated with which RTA
1 - stONE
proximal renal tubular acidosis type 2 - defect
defect in PCT bicarb HCO3- resorption, leads to increased xcretion of bicarb in the urine and metabolic acidosis. Urine can be acidified by alpha intercalated cells in collecting duct but not enough to overcome increase in bicarb excretion
urine pH in RTA 2
> 5.5 when reparative threshold for serum bicarb is exceeded;
<5.5 when bicarb depleted below resorptive threshold
serum K in RTA 2
decreased, hypokalemic
causes of proximal RTA 2
fanconi syndrome, multiple myeloma, carbonic anhydrase inhibitors
associations with pRTA2
increased risk for hypophosphatemic rickets (in fanconi syndrome)
hyperkalemic tubular acidosis type 4 defect
hypoaldosteronism or aldosterone resistance; hyperkalemia (not excreting potassium) leads to a decrease in ammonia NH3 synthesis in PCT, leads to a decrease in ammonium excretion
urine pH in hyperkalemic RTA 4
less than 5.5 or variable
causes of hyperkalemic tubular acidosis type 4
decreased aldosterone production (ex: diabetic hyporeninism, Ace inhibitors, ARBs, NSAIDS, heparin, cyclosporine, adrenal insufficiency or aldosterone resistance ( K+ sparing diuretics, nephropathy due to obstruction, TMP-SMX)
general definition of renal tubular acidosis
disorder of the renal tubules that causes normal anion gap (hyperchloremic) metabolic acidosis)
