Decreased macular leukocyte velocity in human immunodeficiency virus-infected individuals

PURPOSE: To determine whether human immunodeficiency virus (HIV)-infected individuals have decreased macular capillary blood flow in vivo. DESIGN: Case control study. METHODS: Macular leukocyte velocity and perceived leukocyte density were determined in 41 HIV-infected individuals without cytomegalovirus retinitis and 31 HIV-negative control subjects using the blue field simulation technique (BFS-2000, Oculix, Inc., Jenkintown, PA). Velocity and density measurements for HIV-infected individuals were compared to current and lowest previous CD4+ T-lymphocyte counts, HIV RNA blood levels, and blood leukocyte counts. RESULTS: Mean macular leukocyte velocity was lower in HIV-infected individuals than in controls ( P = 0.0006). No correlations were identified between velocity measurements and the following factors in HIV-infected individuals: current or lowest previous CD4+ T-lymphocyte count; or HIV RNA blood level. Mean perceived leukocyte density in HIV-infected individuals was lower than in controls ( P = 0.003), but was not correlated with blood leukocyte count in HIV-infected individuals. No relationships were identified between macular leukocyte velocity and duration of medication use or duration of elevated CD4+ T-lymphocyte count in patients receiving potent antiretroviral therapy. CONCLUSIONS: Reduced macular leukocyte velocity may have important implications for understanding the retinal microvasculopathy of HIV disease, the pathogenesis of opportunistic retinal infections, and visual dysfunction in HIV-infected individuals who do not have opportunistic retinal infections. We found no evidence that macular leukocyte velocity increased with immune reconstitution.