Cervical cytology and Chlamydia trachomatis infection.

We found, as have others, a strong correlation between indirect immunofluorescence techniques and cell culture for the diagnosis of Chlamydia trachomatis infection in material obtained from the cervix. Five epithelial cell types indicative of Chlamydia trachomatis infection (indicator cells) were found in smears in patients with positive immunofluorescence. An attempt to diagnose Chlamydia trachomatis infection in 50 routine smears based on the presence of these indicator cells showed false positives and false negatives so that the diagnosis of Chlamydia trachomatis still requires confirmation by immunofluorescence or culture techniques. The indicator cells frequently had the same morphometric features as cells seen with cervical intraepithelial neoplasia, which may explain why some smears revert to normal after patients are given antibiotics.