Background: Trichomonasis is a sexually transmitted disease with known side effects. The present study was carried out to determine the frequency of trichomonasis and its cytological alterations in a group of symptomatic females referring to a gynecology clinic in Kashan in 1378.

Materials and methods: For this existing data type study, all pop smear samples were stained according to Papanicolae technique and cytological alterations of trichomonasis were also determined. The possible role of age and clinical manifestation were also clarified.

Results: Totally, 1010 samples gathered. Infection with trichomonas vaginalis was reported in 9.9%, where, most of the affected subjects aged 18-35 years. Trichomonatic secretion, cervisitis, and ulcer were the most common clinical manifestations. Cytological alterations were: severe infiltration (36%), perinulear areola(30%), metaplasia(30%), meganucleous(28%), parabasal cells (26%), multiple nucleolus(24%), eosinophilia(22%), cytoplasmic vaculization(22%), cytolysis(21%),nucleolus deformity(15%), and hyperkeratosis(12%).

Conclusion: Great cytological alterations typically for trichomonasis such as severe infiltration, and perinulear areola may help us to diagnose trichomonasis in routine pop smear test.