Oral hairy leukoplakia among HIV-positive intravenous drug abusers: a clinicopathologic and ultrastructural study.

During a prospective investigation of oral lesions of 120 consecutive patients positive for human immunodeficiency virus, belonging to the intravenous drug abuser risk group and other risk categories, we observed hairy leukoplakia (HL) in 23 cases (19%). The median age of the patients was 27 years (range, 20 to 50 years). Twenty patients were men and three were women. All but two of the twenty three patients used intravenous drugs for a median period of 6 years (range, 5 to 18 years) and were involved in several episodes of needle sharing. Eight men were also bisexual, one man was homosexual, and one man was hemophiliac and bisexual. Eleven patients had asymptomatic infection, five had lymphadenopathy syndrome, six had AIDS-related complex, and one had acquired immunodeficiency syndrome. In all patients, HL lesions were localized on the lateral borders of the tongue. In twelve patients, the lesion was unilateral, and in eleven patients, it was bilateral. Microscopically, hyperparakeratosis and the presence of koilocytes were observed in all cases. Surface candidiasis could be detected with staining with periodic acid-Schiff in two thirds of the cases. In four cases, electron microscopy showed the presence of intracellular and extracellular hyphae of Candida albicans in the parakeratin layer associated with coccobacilli in the spaces between surface epithelial cells. The spinous layer included koilocytes, which had a clear cytoplasmic matrix, sparse organelles and tonofilaments, and dispersed chromatin. These cells were found to be infected by a herpes-type virus in all cases examined. There was no ultrastructural evidence of human papillomavirus in the nuclei of the epithelial cells.(ABSTRACT TRUNCATED AT 250 WORDS)