Predicting tubal factor infertility by using markers of humoral and cell-mediated immune response against Chlamydia trachomatis.

PROBLEM: The accuracy of Chlamydia trachomatis antibody test in predicting tubal factor infertility (TFI) is limited, and more accurate methods are needed. Cell-mediated immune response (CMI) is crucial in the resolution of pathogen, but it may play an important role in the pathogenesis of C trachomatis-associated tubal damage. We studied whether combining the markers of C trachomatis-induced CMI to humoral immune response improves the accuracy of serology in TFI prediction.

METHOD OF STUDY: Our prospective study consists of 258 subfertile women, of whom 22 (8.5%) had TFI. Women with other causes for subfertility served as a reference group. Serum C trachomatis major outer membrane protein (MOMP) and chlamydial heat-shock protein 60 (cHSP60) IgG antibodies were measured by ELISA. CMI was studied by lymphocyte proliferation assay in vitro.

RESULTS: Serological markers were more prevalent in women with TFI than in other subfertile women (40.9% vs 12.3% for MOMP IgG and 27.3% vs 10.2% for cHSP60 IgG). The best test combination for TFI was C. trachomatis MOMP and cHSP60 antibody with an accuracy of 90.3%, sensitivity of 22.7% and specificity of 96.6%. Positive post-test probability of this combination was 54.2%, and negative post-test probability was 12.4%. Adding of the markers of CMI did not significantly improve the accuracy of serology in TFI prediction.

CONCLUSION: The accuracy of TFI prediction increases when the combination of C trachomatis MOMP and cHSP60 antibody tests is used. C trachomatis-induced CMI was common in our study population, but the markers of CMI did not predict TFI.