Pseudotuberculous pyelonephritis associated with nephrolithiasis.

This report describes a 40-year-old man with an unusual form of granulomatous pyelonephritis, associated with nephrolithiasis, resulting in end-stage kidney disease and right pretransplant nephrectomy. The kidney specimen contained a staghorn calculus and showed chronic inflammation with confluent caseating granulomas and multinucleated giant cells, resembling renal tuberculosis. However, neither tubercle bacilli nor other microorganisms were demonstrated in the renal tissue or in urine cultures. Because these findings do not support a tuberculous etiology of the granulomatous pyelonephritis, we conclude that this patient had a pseudotuberculous reaction as a consequence of nephrolithiasis.