A comparison of culture, direct fluorescent antibody test, and a quantitative indirect immunoperoxidase assay for detection of Chlamydia trachomatis in pregnant women.

An indirect immunoperoxidase assay that quantitates antichlamydial immunoglobulin G (IgG) and IgA antibodies in serum was compared with endocervical culture and direct fluorescent antibody (MicroTrak) for detection of Chlamydia trachomatis in asymptomatic pregnant women. Of the 64 women tested by the three methods, 22 (34%) had antichlamydial IgG and IgA in their serum. The culture was positive in nine patients (14%) and the MicroTrak was positive in eight (12.5%). All positive cultures were immunoperoxidase-positive. One positive MicroTrak was immunoperoxidase- and culture-negative. Thirteen patients had IgG and IgA antichlamydial antibodies with no organisms detected in the endocervix by culture or by direct fluorescent antibody screen.