Type 1 RTA

Great summary statement at noon report: 
Young woman with a history of intermittent hypokalemia who presented with severe weakness and cramping with near paralysis a couple days after exertion found to have severe hypokalemia and a Type 1 (likely familial) RTA.

Three learning points:

Hypokalemic Periodic Paralysis: An example illness script may be - A teenage boy with sudden attacks of generalized weakness lasting several hours occurring after vigorous exercise, whose mother has similar attacks.

Those with hypokalemic periodic paralysis will have normal potassium levels between episodes, where as those with secondary causes of hypokalemic paralysis (i.e. RTA) will continue to have low potassium levels.

Causes of Type 1 (distal) RTA:

  • Familial
  • Autoimmune: Sjogren's, PBC, Autoimmune hepatitis, SLE, RA
  • Drugs: Ibuprofen, Lithium, Amphotericin B, Ifosfamide
  • Hypercalciuric Conditions: Hyperparathyroidism, Vit D intoxication, Sarcoidosis
  • Idiopathic/Other (Wilson's, obstructive uropathy, renal transplant rejection, medullary sponge kidney)