薬物療法のみで消失したサンゴ状酸性尿酸アンモニウム結石の1例

Abstract

We report a case of a staghorn stone containing ammonium acid urate that was effectively treated with drug therapy alone. A 46-year-old man had recurring urinary tract stones. He had no previous episode of urinary tract stones that required hospitalization and operation. He received only drug therapy for hyperuricemia in another hospital. Ultrasonography and computed tomography revealed a left staghorn stone measuring 37×34 mm. The kidney-ureter-bladder radiograph did not show any stones. His urine was acidic, and we estimated that the left staghorn stone consisted of urate. Oral administration of sodium hydrogen carbonate was initiated to alkalize the urine, and treatment with transurethral lithotripsy (TUL) was scheduled. Before the TUL, analysis of an excreted stone sample revealed that it consisted of ammonium acid urate. The staghorn stone was completely removed in 10 months after the first medical examination. At present, the patient is free of urinary tract stones.