Hairy leukoplakia is a condition thought to be caused by the Epstein-Barr virus (EBV), a member of the herpes virus family which is commonly found in the mouth. It was originally thought that hairy leukoplakia only ever occurred in people with HIV but there have since been cases in other people with suppressed immune systems such as organ transplant recipients.

It is not dangerous in itself, and can occur relatively early in the course of HIV infection as one of the first symptoms a person may have. However, it is a sign that the immune system is weakening and that the person may be at increased risk of other, more serious infections in the coming months.

Symptoms and diagnosis

It causes irregular white patches on the side of the tongue and occasionally elsewhere on the tongue or in the mouth. The patches look corrugated or folded in appearance with tiny hair-like protrusions running along the folds; these can be seen best when the tongue is stuck out and stretched to one side.

The patches look quite similar to candida (thrush), except hairy leukoplakia lesions cannot be moved or dislodged.

It is usually diagnosed simply by examining it. Sometimes it is mistaken for Candida, but it does not respond to the anti-fungal treatments used to treat Candida. If needs be it can be definitively diagnosed by examining a biopsy sample under the microscope.

Treatment and prevention

Hairy leukoplakia in itself does not usually need to be treated, unless it is causing pain, interfering with eating or affecting your voice. If so, it usually responds to high doses (3 grams/day) of the standard anti-herpes drug acyclovir, and may clear up if you are taking similar anti-CMV drugs such as ganciclovir. However, lesions may reappear when antiviral treatment is stopped.

It has also been reported to respond to the anti-wart treatment podophyllin and retinoic acid gels. Surgery to remove the lesions is also an option.

Treatment with an antiretroviral combination is associated with lower prevalence of hairy leukoplakia (Ceballos-Salobreñ¡» Tappuni; Patton). If you are not already taking anti-HIV therapy, you may want to consider treatment if you develop hairy leukoplakia.

The risk of hairy leukoplakia has been reported to be reduced among people who receive fluconazole as anti-Candida prophylaxis. The risk appears to be increased among smokers.

Research

Tappuni conducted a cross sectional study of oral manifestations among HIV-positive patients at St Thomas' Hospital, London. 195 of the group were not on treatment. Overall, the rate of oral infections was lower among those on treatment, with rates of hairy leukoplakia 11% among the untreated group and 4% among those on anti-HIV therapy.

Patton reported the prevalence of HIV-associated oral lesions in 570 HIV-infected people. Comparing 271 patients who presented between Feb 1995-Aug 1996 and 299 who presented between Dec 1996-Feb 1999, the overall prevalence of oral lesions fell from 47.6% to 37.5% (p=0.01). Prevalence of oral hairy leukoplakis fell from 25.8% to 11.4% (p=0.01).

Herbst enrolled 45 gay men with HIV-related hairy leukoplakia in a 3-month open-label study. In 14 participants who had surgical excision, pain resolved in four symptomatic patients and the leukoplakia did not recur in the areas of excision. New foci of leukoplakia, however, appeared in 10 patients after 3 months. Of the 16 participants who received acyclovir therapy, 12 had a clinical regression, although recurrences were noted in all patients after 3 months. Three patients had resolution of pain while taking acyclovir; in two the pain recurred after acyclovir was discontinued. No spontaneous remissions of the leukoplakia occurred in the 15 patients who refused therapy.

Nichols treated 52 HIV-positive adults who had oral hairy leukoplakia with podophyllin resin until resolution or no clinical reduction in lesion size occurred. The mean number of treatments was 2.2. Complete resolution occurred in 78%. Mean reduction in lesion size was assessed to be 92%. Leukoplakia recurred in 17% of cases after a mean interval of 17 weeks. Side-effects of change/loss of taste, allergic reaction, pain and dysphagia from podophyllin occurred in 13%.

Boulter reported that among a group of 56 HIV-positive people, the risk of overt oral Epstein-Barr virus activity was associated with cigarette smoking. A reduced risk was associated with alcohol drinking, elevated CD8 counts and fluconazole therapy.

References

Boulter AW et al. Risk factors associated with Epstein-Barr virus replication in oral epithelial cells of HIV-infected individuals. AIDS 10: 935-940, 1996.

Ceballos-Salobre񡠁 et al. Oral lesions in HIV/AIDS patients undergoing highly active antiretroviral treatment including protease inhibitors: a new face of oral AIDS? AIDS Patient Care and STDs 14(12): 627-635, 2000.

Herbst JS et al. Comparison of the efficacy of surgery and acyclovir therapy in oral hairy leukoplakia. Journal of the American Academy of Dermatology 21(4 Pt 1): 753-756, 1989.

Kessler HA et al. Regression of oral hairy leukoplakia during zidovudine therapy. Archives of Internal Medicine148: 2496-2497, 1988.

Lozada-Nur F et al. Podophyllin resin 25% for treatment of oral hairy leukoplakia: an old treatment for a new lesion. Journal of AIDS 4(5): 543-546, 1991.

Meier JI. Management and prevention of Epstein-Barr virus infections. pp.53-58. In: Straus SE (moderator). Epstein-Barr virus infections: biology, pathogenesis, and management. Annals of Internal Medicine 118: 45-58, 1992.

Newman C et al. Resolution of oral hairy leukoplakia during therapy with 9-(1,3-dihydroxy-2-propoxymethyl) guanine (DHPG). Annals of Internal Medicine 107: 348-350,1987.

Nichols CM et al. Role of podophyllin resin therapy in oral hairy leukoplakia in HIV infection: clinicopathological study. Eleventh International Conference on AIDS, Vancouver, abstract Th.B.4272, 1996.

Patton LL et al. Changing prevalence of oral manifestations of human immuno-deficiency virus in the era of protease inhibitor therapy. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics 89(3): 299-304, 2000.

Resnick L et al. Regression of oral hairy leukoplakia after orally administered acyclovir therapy. Journal of the American Medical Association 259: 384-388, 1988.

Tappuni AR et al. The effect of antiretroviral therapy on the prevalence of oral manifestations in HIV-infected patients: a UK study. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology and Endodontics 92(6): 623-628, 2001.