Renal distal tubular acidosis in obstructive nephropathy.

The acidifying capacity of the kidney was studied in patients with obstructive nephropathy. After a loading test with ammonium chloride, incomplete renal tubular acidosis (RTA) could be observed in 22.5% and stone formation in 30% of the patients with renal tubular acidosis. Attention is called to the fact that, in addition to the known anatomical and physicochemical factors, the alkali fixed urine due to incomplete tubular acidosis due to urinary tract obstruction also predisposes to calculus formation.