Urinary-tract infections: etiology, microbiology, pathophysiology, diagnosis and management.

The increased incidence of urinary-tract infections (UTI) may be due to prolonged human longevity, increased drug resistance of pathogens, poor resistance of the urothelium and the existence of bacterial L forms. About 95 percent of recurrent infections are re-infections. The most common uropathogen is Escherichia coli, and the most virulent is Pseudomonas. UTI may be manifested as: a) asymptomatic bacteriuria, b) acute uncomplicated infection, c) acute complicated infection, or d) recurrent infection. Recurrent infections usually are refractory to treatment, and are caused by a pathogen different from the original one. Upper-tract (kidney) infections are difficult to cure, whereas bladder infections respond favorably. Prostatitis also responds poorly because effective drug levels are difficult to attain in prostatic tissue. Results of the antibody-coated bacteria test (ACB) and the bladder-washout test are helpful in locating the site of infection. Detailed outlines concerning diagnosis, management, chemotherapy and prophylaxis provide data on various types of infection and the effects of specific antimicrobial agents and other drugs at different sites in the urinary tract. A current plan for short-course prophylaxis does not fulfill expectations.