Antimicrobial susceptibility testing of Chlamydia trachomatis using a reverse transcriptase PCR-based method

The conventional method for antimicrobial susceptibility testing of Chlamyd ia trachomatis is subjective and potentially misleading. We have developed a reverse transcriptase PCR (RT-PCR)-based method which is more sensitive a nd less subjective than the conventional method. Using 16 strains of C. tra chomatis in triplicate assays, we found the RT-PCR method consistently more sensitive than the conventional technique for all eight antimicrobials tes ted, with resultant MICs determined by RT-PCR ranging from 1.6-fold higher (erythromycin) to greater than or equal to 195-fold higher (amoxicillin).