Etiology

  • Autoimmune (Sjogren’s), drugs (amphotericin B), CKD

  • Hereditary tubular defects

  • Hyperkalemic causes (hypoaldosteronism)

Pathogenesis

  • Impaired acid secretion or bicarbonate reabsorption → metabolic acidosis

  • Types I (distal), II (proximal), IV (hyperkalemic)

Clinical Features

  • Metabolic acidosis with normal anion gap

  • Hypokalemia (types I and II)

  • Kidney stones (type I)

  • Growth failure in children

Treatment

  • Oral bicarbonate

  • Potassium citrate

  • Treat underlying cause

  • Fludrocortisone for type IV