An algorithm to detect Chlamydia trachomatis by polymerase chain reaction on specimens extracted for enzyme immunoassay

Amplification assays for detecting Chlamydia trachomatis have been shown to be more sensitive than enzyme immuno-assay (EIA) by many investigators. In this study, we have developed an algorithm for performing PCR (COBAS AMPLI COR(TM)) oil selected specimens extracted for EIA (ACCESS(R)) with sample-t o-cutoff (s/co) values between 0.25 and 0.99. Furthermore, we have shown th at these specimens can be utilized for PCR without encountering any inhibit ion problems. In our investigation, 230 out of 6,558 urethral al and cervic al swabs submitted for C. trachomatis screening by EIA over a period of 9 m onths, had s/co values ranging between of 0.25 and 0.99. Ninety (39.1%) of these specimens tested positive by PCR. These specimens were stable and gav e reproducible PCR results before and after storage for a period of 9 month s. This testing algorithm offers an effective way of detecting C. trachomat is with selective use of PCR while increasing the sensitivity of the EIA sc reening system. (C) 1998 Elsevier Science Inc.