Massive amoxycillin crystalluria causing anuric acute renal failure.

The authors report the case of a 45-year-old woman admitted for pneumonia who presented anuric acute renal failure after 12 days of intravenous amoxycillin-clavulanate treatment. Acute renal failure resolved rapidly and completely after antibiotic withdrawal. Analysis of the first post-anuric urine specimen showed many crystals. Infrared spectrophotometry revealed that the crystals were composed of trihydrated amoxycillin. The possibility of intrarenal obstruction due to massive drug crystalluria should not be overlooked in the face of abrupt anuria.