Detection of chlamydia trachomatis by polymerase chain reaction assay in nonbacterial prostatitis

To evaluate the sensitivity and specificity of polymerase chain reaction (PCR) technique in comparison with diethylaminoethyl-dextran (DEAE-dextran)-treated HeLa cell culture method for detection of chlamydia trachomatis in nonbacterial prostatitis.

Thirty patients had symptoms of prostatitis for at least three months. None of them had evidence of urethritis on urethral Gram stain or recurrent bacteria. Routine localization of bacteria was negative. White blood cell count in expressed prostatic secretion (EPS) was more than 10 per high-power field (10/HPF). None of these patients had received antibiotics during the six weeks before the study, although all had received multiple courses of antibiotics for treatment of prostatitis syndrome. The EPS specimens from these patients were placed in 0.5-ml Eppendorf tubes and stored at -70 degrees C until they were processed for PCR and DEAE-dextran-treated HeLa cell culture.

Six specimens were positive for C. trachomatis by both PCR and culture, and 21 were negative by both tests. There were three specimens with discrepant results, including two that were positive by PCR and negative by culture, and one that was positive by culture and negative by PCR. Comparing PCR technique with culture method, the sensitivity, specificity, positive predictive value and negative predictive value of the former were 85.7%, 91.3%, 75.0% and 95.5% respectively.

PCR analysis of EPS is a highly sensitive and specific noninvasive technique for detection of chlamydia trachomatis. It provides a unique opportunity for early identification of or rapid screening for chlamydia trachomatis infection in patients with nonbacterial prostatitis. The reliability of PCR assay offers clinicians a clear indication for the initiation of treatment of chlamydia trachomatis infection.