11 RTA

  • many times asymptomatic, discovered on routine blood work
  • changes bicarb level: non-anion gap

Type 1

  • H channel defect, can't secrete H
  • K held in lumen, no absorption

  • in metabolic acidosis, urine should be low to excrete H
  • if high pH, there's defect excreting H

  • bilateral stones: think distal RTA

Calcium binds to negative albumin, competing with hydrogen ions

  • Alkalosis: less H+ competing, more Ca binding, which decreases free calcium levels.
  • Acidosis, increase H+ competing, less Ca binding, resulting in increased free calcium levels

  • very very high yield: sjogren or RA

  • 1 shaped acid tube: renal tubular acidosis (RTA) type 1 is cumulative toxicity of amphotericin
  • Depleted potassium banana peel: RTA type 1 is associated with hypokalemia

Urine Anion Gap

  • urinary anion gap equation different from plasma anion gap
  • urine Cl goes up, UAG becomes negative

Type 2

  • Fan cone: Fanconi syndrome (type 2 RTA) associated with use of expired tetracyclines

Type 4

  • aldosterone doesn't work > hyperkalemia
  • hyperkalemia > increased K into cell, increased H out of cell> high pH in PCT cells
  • high pH > unable to excrete H and NH3
  • Inadequate amount of NH3 available for buffering of protons. Even if only a few protons are secreted distally, urinary pH will fall in the absence of buffers.

  • diabetic renal: less renin production from renal insufficiency
  • ace/ARB: less aldosterone
  • bactrim: disrupt K excretion
  • Hyperkalemic RTA is commonly seen in elderly patients who have poorly controlled diabetes with damage to the juxtaglomerular apparatus, which causes a state of hyporeninemic hypoaldosteronism.

  • ACE I: high potassium cup

  • Depleted mineral mine: NSAIDs can cause hypoaldosteronism (decreased mineralocorticoids)
  • Big K: NSAID induced hypoaldosteronism can cause hyperkalemia. Type 4 RTA

  • Mad scientist with 4 tubes of acid: Type IV renal tubular acidosis (RTA)
  • K shape: Type IV RTA leads to hyperkalemia

  • Elevated bananas: K+ sparing diuretics can cause hyperkalemia
  • Acid spill into intracellular space: K+ sparing diuretics cause a normal anion gap metabolic acidosis (by decreasing the function of the H+ATPase)
  • 4 acid tubes: K+ sparing diuretics inhibit the effects of aldosterone in the collecting duct causing a type 4 renal tubular acidosis (RTA)
  • Big K: type 4 RTA is associated with hyperkalemia

  • Depleted mineral mine: heparin can cause hypoaldosteronism (a mineralocorticoid)
  • Big K: heparin induced hypoaldosteronism (Type 4 RTA) causes hyperkalemia

  • fludrocortisone: synthetic aldosterone