Stability of cutaneous anergy in women with or at risk for HIV infection

Objective: To study the stability of cutaneous anergy in women with or at risk for HIV infection. Design: Prospective multicenter cohort study Methods: Interviews, CD4⁺ lymphocyte counts, and intradermal skin testing with mumps, Candida, and tetanus toxoid antigens were performed on two occasions at a median interval of 74 weeks in 436 HIV-seropositive and 252 seronegative at-risk women; only 10 (2%) HIV-seropositive women were taking highly active antiretroviral therapy at the time of delayed-type hypersensitivity (DTH) testing. Anergy was defined as induration <2 mm to all three antigens. Results: Skin test reactivity at repeat testing was seen in 202 of 233 (87%) HIV-seronegative women who were not anergic at baseline, compared with 10 (53%) of 19 seronegative women who were anergic at baseline (relative risk [RR], 1.7; 95% confidence interval [CI], 1.07-2.5). Anergy at retesting was seen in 108 of 169 (64%) HIV-seropositive women who were previously anergic, compared with 77 of 267 (29%) who were not previously anergic (RR, 2.2; 95% CI, 1.8-2.8). Among initially anergic seropositive women, CD4⁺ lymphocyte counts were lower at both initial and follow-up testing in those who remained anergic than in those who reacted at follow-up (p < .001). The relative risks for anergy at retesting of initially anergic seropositive women, compared with initially reactive seropositive women, were related to CD4⁺ level; 2.5 (95% CI, 1.4-4.3) for CD4⁺ counts < 200 cells/mm³, 2.0 (95% CI, 1.5-1.7) for CD4⁺ counts 200-500 cells/mm³, and 1.6 (95% CI, 0.9-2.8) for CD4⁺ counts >500 cells/mm³. Conclusions: Although anergic HIV-seropositive women may become reactive, cutaneous anergy predicts a higher likelihood of anergy at retesting as well as lower CD4⁺ counts. Stability of anergy is greatest in HIV-seropositive women with low CD4⁺ counts.