Unilateral or bilateral nonpainful white lesions can be seen on the margins, dorsal or ventral surfaces of the tongue, or on buccal mucosa. The lesions may vary in appearance from smooth, flat, small lesions to irregular "hairy" or "feathery" lesions with prominent folds or projections.
Lesions may be either continuous or discontinuous along both tongue borders, and they are often not bilaterally symmetric. Lesions are adherent, and only the most superficial layers can be removed by scraping. There is no associated erythema or edema of the surrounding tissue. Hairy leukoplakia may also involve dorsal and ventral tongue surfaces, the buccal mucosa, or the gingiva. On the ventral tongue, buccal mucosa, or gingiva, the lesion may be flat and smooth, lacking the characteristic "hairy" appearance.
Causes
Oral hairy leukoplakia has been associated with HIV infection and/or immunosuppression.[10] The risk of developing oral hairy leukoplakia doubles with each 300-unit decrease in CD4 count. A high viral load was strongly associated to the oral lesions occurrence independently of CD4+ cell count.[4] More recently, it has been described in patients with other forms of severe immunodeficiency including those associated with chemotherapy, organ transplant, and leukemia. Rarely, it may occur in patients who are immunocompetent.
Oral hairy leukoplakia also has been described in association with Behçet syndrome and ulcerative colitis.
Smoking more than a pack of cigarettes a day is positively correlated with the development of oral hairy leukoplakia in HIV positive men.
No increase in oral hairy leukoplakia was observed when controlled for number of oral sex partners.
