Diagnostic considerations and interpretation of microbiological findings for evaluation of chronic prostatitis.

Seventy-five patients attending a clinic for chronic prostatitis were evaluated by use of lower urinary tract localization cultures. Coagulase-negative staphylococci, alpha-hemolytic streptococci, and diphtheroids were the most common isolates, but none of these organisms were pathogens, based on the absence of bacteriuria or evidence of an inflammatory response in prostatic secretions. Recognized uropathogens were isolated in 12 (16%) of the 75 cases and included Escherichia coli in 6 cases, Enterococcus spp. in 2 cases, and Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter cloacae, and Staphylococcus saprophyticus in 1 case each. Laboratory evaluation of men with chronic prostatitis should concentrate on the isolation and antimicrobial susceptibility testing of bacteria that have an established pathogenic potential in the genitourinary tract.