Hypocitraturic and hypercalciuric renal tubular acidosis with nephrocalcinosis in a 4-year-old boy.

A 4-year-old boy suffering from hypocitraturic and hypercalciuric renal tubular acidosis with nephrolithiasis and nephrocalcinosis is reported. Renal function tests indicated that the patient had type 1 renal tubular acidosis. Potassium citrate rather than potassium bicarbonate, sodium citrate or bicarbonate is the preferred treatment for stones in RTA-I.