BILATERAL HYDRONEPHROSIS FROM CIPROFLOXACIN INDUCED CRYSTALLURIA AND STONE FORMATION

Abstract

Ciprofloxacin is a widely used fluoroquinolone for the treatment of complicated and uncomplicated infections. Experimental studies in humans and animals have indicated that crystalluria may be associated with the administration of fluoroquinolones but, to our knowledge, no case of obstructive uropathy has been reported.'.' We describe a case of bilateral urinary tract obstruction and acute renal failure due to urinary tract stones predominantly composed of ciprofloxacin. CASE REPORT A 71-year-old white woman was admitted to the hospital with a 2-week history of intermittent gross hematuria, bilateral lower extremity edema and respiratory distress. Medical history was remarkable for deforming rheumatoid arthritis and moderate left ventricular dysfunction. Lower extremity deep vein thrombosis had been diagnosed 2 months earlier and warfarin sodium anticoagulation was prescribed. There was no history of azotemia, proteinuria, hematuria or nephrolithiasis. Symptoms of dysuria had developed 3 weeks earlier and 500 mg. ciprofloxacin were given orally twice daily for a total of 24 days for presumed urinary tract infection. Physical examination revealed an elderly white woman with diffuse expiratory wheezes and bilateral lower extremity edema. Creatinine was 3.1 mg./dl. (normal 0.6 to 1.4), uric acid 10.5 mg./dl. (normal 2.3 to 6.0) and urine pH 6.0 (normal 4.5 to 8.0). Grossly, urine contained copious gray sediment. Microscopically, a large number of crystals of varying morphology were present. A renal sonogram revealed normal size kidneys of normal echogenicity with bilateral hydronephrosis and 24-hour urine uric acid was 568 mg. (normal 250 to 750). Cystoscopy with bilateral retrograde pyelography and stent placement were performed. A large amount of friable crystalline material was present in the bladder and multiple radiolucent filling defects were identified in the distal ureters bilaterally (see figure). A specimen of the friable calculus was composed of 15% uric acid and 85% ciprofloxacin. Intravenous hydration was maintained and allopurinol was started. The urine sediment cleared rapidly, renal function returned to previous baseline levels and serum creatinine decreased to 0.7 mg./dl. within 72 hours. DISCUSSION