Relationship Between Opacity of Cytomegalovirus Retinitis Lesion Borders and Severity of Immunodeficiency Among People With AIDS

PURPOSE. To evaluate risk factors for severity of cytomegalovirus (CMV) retinitis lesion whitening (opacity), using a standardized scoring system. METHODS. We performed a cross-sectional, observational investigation of all individuals with newly diagnosed AIDS-related CMV retinitis in three randomized clinical trials and one prospective observational study. Opacity was scored by masked readers, using a prospectively defined ordinal 6-point scale. Demographic factors, laboratory data (CD4+, CD8+ Tlymphocyte counts, human immunodeficiency virus [HIV] blood levels), and lesion characteristics (location, size) were compared to the highest opacity score assigned to either eye. Among eyes with active lesions (scores >= 3), factors associated with severe opacity (scores 5, 6) were identified. RESULTS. There were 299 participants (401 eyes with CMV retinitis). In one or more comparisons, increased opacity was associated with lower CD4+ and lower CD8+ Tlymphocyte counts, higher HIV blood level, lack of antiretroviral therapy, male sex, race/ethnicity, and bilateral disease. In eyes with active disease, severe opacity was associated with lower CD4+ T-lymphocyte count, higher HIV blood level, older age, Karnofsky score, lesion size, and bilateral disease. No relationship was identified between opacity and lesion location. CONCLUSIONS. Lesion border opacity (resulting from CMV activity) reflects level of immune function; as immunodeficiency becomes worse, CMV activity (and opacity) increases. The positive relationship between opacity and HIV blood level may reflect both immunodeficiency and increased CMV activity caused by transactivation of CMV by HIV. Scoring of opacity may be a useful, standard measure for continued study of CMV retinitis across different settings and populations.