Background: In patients with psoriasis and human immunodeficiency virus type 1 (HIV-1) infection, therapeutic options may be limited by their potential immunosuppressive effects. UVB radiation can activate HIV-1 gene expression in transgenic mice and in vitro. It is not known whether this viral activation leads to a clinically significant effect or if these findings can be extrapolated to humans.

Objective: This study was performed to evaluate the safety of UVB light treatment in HIV-infected persons.

Methods: We prospectively studied the effect of UVB phototherapy on five HIV-infected patients with psoriasis and one with pruritus. A complete blood cell count with differential count, CD4⁺ and CD8⁺ T-lymphocyte counts, serum β₂-microglobulin and HIV-1 p24 antigen were obtained before UVB phototherapy and after 21 and 42 treatments. After every five treatments patients were evaluated for opportunistic infections, and psoriatic involvement was quantified with the Psoriasis Area and Severity Index (PASI).

Results: Cumulative UVB doses ranged from 3326 to 43,364 mJ/cm². There were no statistically significant changes in laboratory findings after 21 and 42 treatments. Of three patients without detectable serum levels of HIV-1 p24 antigen before phototherapy, only one became positive after 42 treatments. None of the six subjects had an opportunistic infection or malignancy during phototherapy. The PASI improved in all five patients with psoriasis, and the other patient noticed decreased pruritus.

Conclusion: Our results suggest that UVB phototherapy is efficacious in HIV-1-infected patients with UVB-responsive dermatoses and is not associated with short-term changes in immune function.