[Studies on detection of serum IgA and IgG antibodies specific for Chlamydia trachomatis in latent infections in males].

We determined the serum concentrations of IgA and IgG antibodies specific for Chlamydia trachomatis (C. trachomatis) by an indirect immunoperoxidase assay (IPAzyme kit, Savyon Diagnostics, Ltd., Bee, Shova, Israel) to evaluate their diagnostic significance in latent infections in males. Forty-five asymptomatic males whose wife or partner was suspected to be infected with C. trachomatis were studied and the incidence of serum IgA (titer greater than or equal to 16) and IgG (titer greater than or equal to 64) antibodies for C. trachomatis was compared with that in a healthy group, a group with non-gonococcal urethritis (NGU) patients. Changes in IgA titer during treatment were also examined. The incidence of IgA and IgG antibodies in the healthy group was found to be 2.4% and 11.9% in males, and 4.8% and 18.1% in females, respectively. In patients whose wife or partner who was positive to C. trachomatis, the incidence of IgA and IgG antibodies was 42.2% and 75.6%, respectively. In the NGU patients the incidence of IgA and IgG antibodies was 56.3% and 62.5%, respectively. The incidence of IgA and IgG antibodies in patients whose wife or partner was antibody-positive were significantly higher (p less than 0.01) than the corresponding value in healthy men and women, but there was no significant difference from NGU patients or the elderly group. The IgA antibody titer during treatment of C. trachomatis infection showed no reduction in some cases. This study revealed frequent latent incidence of C. trachomatis infection in male patients. Determination of C. trachomatis IgA and IgG antibodies is considered to be supplemental for diagnosis of chlamydial latent infections.