Comparison of plasmid and chromosomal omp1 gene-based PCR and two DNA extraction methods for diagnosing Chlamydia trachomatis in endocervical swab samples

Objective: To evaluate the effectiveness of boiling and proteolytic DNA extraction methods and\udalso to compare the sensitivity of plasmid polymerase chain reaction (PCR) and chromosomal\udomp1 gene PCR for genital Chlamydia trachomatis swab samples in women. Methods: 710\udcervical swab samples were obtained from women with symptomatic genital infection at 11\udgynecology and obstetric clinics located in Ahvaz, Iran. DNA extraction was performed using\udproteolysis and boiling manners for all samples. Plasmid PCR and chromosomal omp1 gene\udprimary- and seminested-PCR were then performed separately on extracted DNA in boiling\udand proteolytic methods. Results: The prevalence of this infection was 17.6% as determined by\udplasmid-PCR, 13.2% by omp1-primary PCR and 15.8% by omp1-nested PCR. Sensitivities of\udboiling and proteolytic extraction-directed PCR were 93.6%, and 68.8%, respectively, which are\udsignificantly different (P=0.02). The sign of swab-induced bleeding was significantly found to\udbe the most frequent among women infected with this bacterium (P=0.001) and had a sensitivity\udof 33.6% and a specificity of 80.5%. Conclusions: In order to obtain confident statistical results\udabout sensitivity of each manner, in present study these evaluations were carried out for high\udnumbers of samples (710 samples); high number of samples is statistical advantage of this study in\udcomparing with other studies which were performed with low numbers of samples. Using boilingDNA extraction manner and targeting plasmid sequence for PCR can increase the sensitivity of C.\udtrachomatis diagnosis