Detection of chlamydia trachomatis in endocervical specimens by an enzyme- linked polymerase chain reaction assay

ABSTRACT

Chlamydia trachomatis [CT] is the most common cause of sexually transmitted infections [STI] worldwide and its early detection and treatment can reduces the high morbidity associated with this infection. In this study a sensitive diagnostic polymerase chain reaction [PCR]-based enzyme immunoassay [PCR-EIA] method was developed which detects CT in women with cervicitis. Endocervical swabs collected from 123 women [20-55 years] with cervicitis were tested by both conventional PCR, and PCR-EIA assays, using identical sets of primers to amplify a CT-specific plasmid. For the conventional PCR, amplicons were detected by agarose gel electrophoretic analysis and the PCR-EIA assay used biotin-labeled primers, strepavidin-coated plates, a digoxigenin-labeled probe, and a final enzyme-linked colorometric analysis [405 nm] was used to measure the CT amplicon. The frequency of positive CT infection by conventional PCR and PCR-EIA assay was 7% and 17%, respectively. The highest frequencies of CT infection were among women of 31-40 years old group [25%]. The PCR-EIA limit of detection, calculated by linear regression analysis, was10 pg of CT DNA [r[2]=0.9642]. The degree of agreement [Kappa] between the conventional PCR and PCR-EIA method was 0.556 [p<0.0001]