Cytopathology of sexually transmitted disease.

Although other methods exist for routine identification of most sexually transmitted diseases, the pathologist can often recognize the etiologic agents or their cytologic effects on Papanicolaou (Pap) smear. Useful clinical information requires both the ability to recognize these effects and knowledge of their limitations. Pap smear changes characteristic of Trichomonas vaginalis, Chlamydia trachomatis, herpes simplex virus, Gardnerella vaginalis, Candida sp., and human papillomavirus infections are described and their diagnostic accuracy evaluated.