Comparison of the Amplicor Chlamydia trachomatis test and cell culture for the detection of urogenital chlamydial infections

Abstract

Objective: To compare the polymerase chain reaction (PCR) Amplicor Chlamydia trachomatis test with the cell culture method, in diagnosing urogenital chlamydial infections.

Subjects: 439 patients (327 women and 112 men) attending one STD clinic and Family Planning and Gynaecological Clinics in Lisbon, Portugal, between November 1993 and March 1994.

Methods: In women, two endocervical swab samples were collected: one for PCR Amplicor and one for standard culture technique. Men were asked to submit 20 ml of urine (first pass urine) for PCR Amplicor and one urethral specimen was taken for culture. The order of collection of the specimens was rotated every 50 patients. Discrepant results were further analysed by a second PCR with primers directed against the C trachomatis major outer membrane protein (MOMP) and by direct fluorescent antibody (DFA).

Results: After analysis of discrepancies, the adjusted sensitivity and specificity of PCR on endocervical specimens were 92.9% and 100% and the positive and negative predictive values were 100% and 99.7% respectively; on the urine samples these values were 100%, 99.1%, 100% and 99.1%, respectively.

Conclusion: These results indicate that the PCR Amplicor test is a rapid sensitive and specific assay for the detection of C trachomatis in urogenital infections and provides a non-invasive technique for screening chlamydia infection in men.