RTA

Type 1 RTA

  • pt: sjogren, RA, kid, amphotericin B
  • cause: distal tubule cannot excrete H or absorb K
  • sx:
    • recurrent bilateral stones
    • rickets disease
    • growth failure in children
  • dx:
    • non AG metabolic acidosis but high urine pH (can't excrete H)
    • acidosis increases Ca excretion (stones)
    • hypokalemia (can't absorb K)
    • hyperchloremia
    • positive urine AG
  • rx: Na bicarb

Type 2 RTA

  • pt
  • cause: can't absorb HCO3 absorption in proximal tubule. Fanconi syndrome
  • sx
    • no stones
  • dx
    • milder metabolic acidosis bicarb 12-20
    • hypokalemia from increased aldosterone from volume contraction
    • urine pH < 5.3

Type 4 RTA

  • pt:
  • cause: aldosterone deficiency or resistance
    • diabetes, ace, arb, nsaids, adrenal insufficiency
    • bactrim, K sparing diuretics
  • sx
  • dx
    • hyperkalemia from decreased K excretion
    • pH < 5.4
  • rx: mineralocorticoid or fludrocortisone