Hematuria and the use of nonsteroidal anti-inflammatory drugs.

We reviewed 116 consecutive adults hospitalized for hematuria (92 with gross and 24 with microscopic hematuria). The cause of hematuria (that is neoplasia, stones, infection and inflammation) was recognized in approximately 79 per cent of the 116 patients (group 1), while 21 per cent (group 2) had idiopathic hematuria. Review of drug history in these 2 groups revealed that nonsteroidal anti-inflammatory drugs were used in 1 per cent of the patients in group 1 compared to 54 per cent in group 2. To confirm these findings we reviewed a control group of 60 patients without hematuria hospitalized for benign prostatic hyperplasia and followup of bladder tumors, and found a 3.3 per cent prevalence of nonsteroidal anti-inflammatory drugs. These findings implicate nonsteroidal anti-inflammatory drug use as a potential cause of idiopathic hematuria.