Nitrosamine formation in bladder infections and its role in the etiology of bladder cancer.

Dimethylnitrosamine, a powerful carcinogen, is produced in the urine of patients with urinary tract infections of Proteus mirabilis and Escherichia coli when nitrite is present. Treatment with tetracycline antibiotics does not enhance the concentration of this carcinogen but, rather, sharply reduces it. The results emphasize the importance of proper antibiotic therapy for the infections to reduce the possibility of the subsequent development of bladder cancer.