Urolithiasis associated with the protease inhibitor indinavir

Objectives. To report the association between the protease inhibitor indinavir and the development of urolithiasis. Methods. Case reports of three adult patients infected with the human immunodeficiency virus who developed surgical renal stones while being treated with indinavir are presented. Results. Of the 3 patients requiring surgical intervention, stone analyses were available in 2. One stone revealed an inner core of an unidentifiable crystal surrounded by calcium oxalate, and another was found to have indinavir components as determined by thin-layer chromatography and gas chromatography-mass spectrometry. Metabolic evaluation of all 5 patients identified significant hypocitraturia as an isolated finding. Conclusions. The widely used protease inhibitor indinavir is associated with the development of urolithiasis and may act as a nidus for heterogeneous nucleation leading to the development of mixed urinary stones. Surgical intervention may be necessary in some cases. Underlying metabolic abnormalities may contribute to the increased incidence of stone formation. Urologists and other health care providers should be aware of this association, as combined medical and surgical intervention may be necessary. (C) 1997, Elsevier Science Inc. All rights reserved.