Diagnosis of hairy leukoplakia by exfoliative cytologic methods.

The cytologic characteristics of hairy leukoplakia (HL) are described based on the findings observed in four lesions. All cases were confirmed by histologic study, and Epstein-Barr virus DNA was detected by means of in situ hybridization of tissue sections. All smears from the lesions exhibited a distinctive appearance and three types of epithelial changes were observed: (1) intranuclear inclusions of Cowdry type A, (2) intranuclear inclusions with a ground-glass appearance, and (3) clumping and margination of chromatin around the nuclear membrane. Other findings were the presence of bacterial colonies in all lesions and Candida organisms in three of them. The results of this study suggest that conventional exfoliative cytologic examination may prove to be a useful, simple, cost-effective, and reliable method to diagnose hairy leukoplakia.