A novel heterozygous mutation in the ATP6V0A4 gene encoding the V-ATPase a4 subunit in an adult patient with incomplete distal renal tubular acidosis

A 40-year-old Japanese man who had a medical history of hypokalemic periodic paralysis 4 months prior was hospitalized to undergo a cholecystectomy. Hypokalemia, nephrocalcinosis and alkaluria suggesting distal renal tubular acidosis (dRTA) were detected, but metabolic acidosis was not evident. An ammonium chloride/furosemide–fludrocortisone/bicarbonate loading test demonstrated a remarkable disability in urinary H+ excretion. A novel heterozygous mutation in the ATP6V0A4 gene encoding the vacuolar H+-ATPase (V-ATPase) a4 subunit p.S544L was detected. Among cases of V-ATPase a4 mutations, this is the first case in which a heterozygous mutation developed to an incomplete or latent form of dRTA.

Source: CKJ: Clinical Kidney Journal - May 30, 2016 Category: Urology & Nephrology Authors: Imai, E., Kaneko, S., Mori, T., Okado, T., Uchida, S., Tsukamoto, Y. Tags: FAMILIAL NEPHROPATHIES Source Type: research