Computed tomography of renal abscesses complicating medullary sponge kidney.

Although urinary tract infection occurs in approximately one-third of symptomatic patients with medullary sponge kidney (MSK), renal abscess is a rare complication of the disorder. We describe two patients with MSK complicated by renal abscesses that were diagnosed by CT. The diagnosis of renal abscess should be suspected in patients with MSK and acute pyelonephritis who do not respond to appropriate antibiotic therapy, and renal CT should be done. Computed tomography may show large abscesses that require percutaneous or open surgical drainage or small abscesses that require prolonged high dose antibiotic therapy.