Comparison of two enzyme immunoassays and an immunofluorescence test for detection of Chlamydia trachomatis

Three rapid methods for the detection of Chlamydia trachomatis were compared: one immunofluorescence test and two enzyme immunoassays. Cervical and urethral specimens were obtained from 75 women in an outpatient clinic for therapeutic abortions and from 50 women in a sexually transmitted disease clinic. Urethral specimens were also obtained from 154 men in the same clinic. One hundred and nineteen cervical and 272 urethral specimens of a total 391 specimens were tested by the three methods. The direct immunofluorescence test detected Chlamydia trachomatis in 8% and the two enzyme immunoassays in 10% and 12% of the patients. The sensitivity of the immunofluorescence test was 76% compared to 91% and 80% for the two enzyme immunoassay tests. All three tests had a specificity of 99%. Dilution experiments confirmed that one immunoassay test, Chlamydiazyme, detected most of the positive specimens. The rapid and easily automated enzyme immunoassays are a valuable complement to the culture technique.