Sexually transmitted infections and infertility in Rwanda: Diagnostic significance of IgG and IgA antibodies testing

Abstract

Background: In many developing countries, little is known about the prevalence of genital Chlamydia trachomatis infections and complications, such as infertility, thus preventing any policy from being formulated regarding screening for C. trachomatis of patients at risk for infertility. The objective of the present study was to determine the prevalence of C. trachomatis and evaluate the diagnostic utility of serological markers namely anti-C. trachomatis IgG and IgA antibodies in women attending an infertility clinic. Methods & Materials: Two commercial species-specific ELISA to determine serum IgG and IgA antibodies to C. trachomatis, PCR onvaginal swabs specimens andHysterosalpingography (HSG)was performed on Serum and vaginal swab specimens of 303 women presenting with infertility to the infertility clinic of the Kigali University Teaching Hospital and 312 fertile controls in subfertile women. Results: The prevalence of C. trachomatis infection by PCR and serological test (IgG and IgA) were relatively low in both subfertile and fertile women and no significant differences in overall prevalence ratesofC. trachomatis amongbothgroupswereobserved. The only factor associated with C. trachomatis infection in our study population was age 25 years. Evidence of tubal pathology identified by HSG was found in 185 patients in the subfertile group (67.8%). All the serological markers measured in this study had very low sensitivities and negative predictive values in predicting tubal pathology. The specificities for ANILabsystems IgG, Vircell IgG, Anilabsystem IgA and positive C. trachomatis DNA to predict tubalpathologywere84,86, 95and98%, respectively,whereas their respective positive predictive values were 73, 76, 81 and 80%. Conclusion: The prevalence of C. trachomatis in our study population in Rwanda appears to be low and women aged 25 years are more likely to have genital infection with C. trachomatis. Since serological testing for Chlamydia shows an excellent negative predictive value for lower genital tract infection, specific peptide-based serological assays may be of use for screening in low prevalence settings. Our data suggest that C. trachomatis is not the primary pathogen responsible for tubal pathology in Rwandan women.