Sensitivity of detecting Chlamydia trachomatis elementary bodies in smears by use of a fluorescein labelled monoclonal antibody: comparison with conventional chlamydial isolation.

Abstract

Commercially produced fluorescein labeled monoclonal antibodies for the detection of C. trachomatis have recently become available. One is for detecting inclusions in cell culture (culture confirmation) and the other for detecting elementary bodies in smears from potentially infected sites. The 2 monoclonal antibodies were compared with a routine isolation method, which utilizes Giemsa staining of cycloheximide treated human McCoy cell cultures. The culture confirmation system offered no advantages over Giemsa staining for the detection of inclusions in cell monolayers. Using monoclonal antibody to detect elementary bodies in smears was much quicker and simpler and slightly more sensitive than isolation of chlamydiae in cell culture. For specimens from 7 babies with conjunctivitis and from 35 female contacts of men with nongonococcal urethritis, there was complete agreement between the results of detecting inclusions in culture and those of seeking elementary bodies in smears. For samples from 100 men with nongonococcal urethritis and from 100 men with gonorrhea there was 99% and 94% agreement, respectively, between the results of the 2 tests. Other aspects and possible uses of the new detection system are discussed.