Urinary calculus containing gas.

The combination of gas in the upper urinary tract along with renal calculi has been reported in the setting of emphysematous renal infections, urinary tract instrumentation, and urinary-gastrointestinal fistulas. We present a case of a 46-year-old nondiabetic man with the isolated finding of a gas-containing renal calculus. The significant history in this case included recurrent urinary tract infections and primary hyperparathyroidism with persistent hypercalcemia despite previous parathyroid explorations. The patient was treated with oral antibiotics and rendered stone and infection free by percutaneous nephrolithotomy. The stone culture was negative, and the stone analysis revealed 100% hydroxyapatite.