Evaluation of diagnostic tools for adult chlamydial keratoconjunctivitis

Conjunctival smears and serum specimens of 150 patients with presumed chlamydial keratoconjunctivitis were evaluated over a period of 16 months and compared to age- and sex-matched healthy controls. Sensitivity, specificity, and predictive values of fluorescent monoclonal antibody (FMAb) direct tests, IgG single antigen tests for the detection of serum antibody (IgG-IFT), and IgA and IgG immunoperoxidase tests (IgA-IPAs and IgG-IPAs) for serum antibody were compared to McCoy cell culture techniques in a nonoptimized clinical setting. Thus, FMAb sensitivity was 100%, specificity was 52%, and predictive value was 30%. IgG-IFT sensitivity was 94%, specificity was 67%, and predictive value was 37%. IgA-IPA sensitivity was 100%, specificity was 70%, and predictive value was 40%. The IgG-IPA was sensitive but nonspecific. With respect to the current epidemiologic situation in our area, FMAb and IgA-IPA in addition to McCoy cell culture techniques may represent valuable diagnostic tools for the detection of chlamydial disease.