2,8-dihydroxyadenine urolithiasis due to partial deficiency of adenine phosphoribosyltransferase: a case report

A 35-year-old female was referred to our clinic with a complaint of left flank pain in 1993. Drip infusion pyelography showed a filling defect of 25 x 24 mm in size in the left ureteropelvic junction. Computed tomography and ultrasonography revealed it as the renal stone. Percutaneous nephroureterolithotomy and extracorporeal shock-were lithotomy were performed. The stone was composed of 2,8-dihydroxyadenine (DHA). The patient was diagnosed as having a partial deficiency of adenine phosphoribosyltransferase (APRT) from the low APRT activity and a genotype of a compound heterozygote APRT*J/APRT*Q0 by T-cell analysis. The urinary excretion of 2,8-DHA crystals disappeared by the postoperative treatment with allopurinol. Cases of 2,8-DHA urolithiasis reported in the Japanese literature are discussed.