Chlamydia trachomatis causes a wide range of
infections in adults and
conjunctivitis and
pneumonia in neonates. The
complement fixation test for chlamydial antibody is broadly reactive, but possesses low sensitivity, whereas the microimmunofluorescence test is highly sensitive, but technically difficult to perform. A simple, rapid
enzyme-linked
immunosorbent assay (ELISA) has been developed for the measurement of
immunoglobulin G (
IgG) and
IgM antibodies to C. trachomatis. Wells of microtiter plates were coated with
Renografin-purified elementary bodies (serotype L2) grown in
cycloheximide-treated McCoy cells, and serum antibody was detected with
peroxidase-labeled goat antihuman
IgG and
IgM antibody. Of 41 sera tested from patients with
lymphogranuloma venereum,
pelvic inflammatory disease,
cervicitis, or
urethritis there was a 90 and 63% correlation of positive results for
IgG and
IgM, respectively, by microimmunofluorescence and ELISA. Of the positive correlates, ELISA titers were up to 128 times higher than microimmunofluorescence titers for
IgG and
IgM. The ELISA detected no false-positive results, but missed two positive results for
IgG. Both of these sera were reactive against serotypes C and J, suggesting that the ELISA with LGV L2
antigen may not measure
antibodies to serotypes within the C serogroup. The
IgM ELISA detected 7 negative and 4 positive results not detected by the microimmunofluorescence test. Of four paired sera examined by ELISA, three showed a fourfold rise in
IgG antibody titer, and one showed a twofold rise. Further evaluation of this ELISA will be required to determine how useful it will be in seroepidemiological studies and as a diagnostic tool.