[Two cases of 2.8-dihydroxyadenine stone with a partial deficiency of adenine phosphoribosyltransferase].

We report two cases of 2.8-dihydroxyadenine stones due to partial deficiency of adenine phosphoribosyltransferase. The first patient is a 41-year-old female. Radiologic examination revealed left radiolucent renal stones and contracted kidney. Left nephrectomy was performed. Infrared spectrometric analysis of the stones revealed 2.8-dihydroxyadenine calculi. The adenine phosphoribosyltransferase activity in lymphocyte (T cell) was 19.5% of the control level. After the operation, the patient was given 300 mg/day of alloprinol. There have been no signs of recurrence. The second patient was a 52-year-old male. Radiologic examination revealed radiolucent stones of the right kidney and the urine bladder. Percutaneous nephrolithotomy and cystolithotripsy were performed. Infrared spectrometric analysis of the stones revealed 2.8-dihydroxyadenine calculi. The adenine phosphoribosyltransferase activity in the lymphocytes (T cell) was 21% of the control level. After the operation the patient was given 200 mg/day of alloprinol and put on a low purine diet. There have been no signs of recurrence.