Background: The clinical features of lichenoid eruptions in the setting of human immunodeficiency virus (HIV) infection are poorly described. Idiopathic lichen planus is rarely reported. All patients (n = 32) with a histologic diagnosis of a lichenoid eruption or photodermatitis at the University of California, San Francisco, over a 15-month period were reviewed and studied.
Observations: Twelve of the 32 patients were HIV infected, and all 12 had photodistributed eruptions. Ten of 12 patients had received photosensitizing medication (usually nonsteroidal anti-inflammatory drugs or sulfamethoxazole/trimethoprim) at the onset of eruption. Most patients were black (10 of 12), and all had acquired immunodeficiency syndrome and a helper T-cell count of less than 50 cells per cubic milliliter. Nine patients had lichenoid eruptions, two showed histopathologic features of lichen niditus, and one had a photodistributed subacute dermatitis. Two patients with lichenoid eruptions developed marked depigmentation. No cases of lichen planus were found in HIV-infected persons.
Conclusion: Lichenoid photoeruptions are seen in advanced HIV disease (CD4, < 0.05 x 10(9)L), and black patients are disproportionately affected. Idiopathic lichen planus in HIV-infected patients seems to be less common than lichenoid photoeruptions. Previously reported cases of idiopathic lichen planus in HIV-infected patients may represent lichenoid photodermatitis.