Criteria for assessing cutaneous anergy in women with or at risk for HIV infection

Background: Controversy exists about both the clinical utility of anergy testing and the optimal criteria for defining anergy. Objective: We sought to assess various definitions of cutaneous anergy for ability to distinguish HIV status, level of immunodeficiency, and ability to mount a tuberculin reaction among women with or at risk for HIV infection. Methods: HIV-seropositive (n = 721) and HIV-seronegative (n = 358) at-risk women at academic medical centers in Baltimore, Detroit, New York, and Providence had cutaneous testing with mumps, Candida, tetanus toxoid, and tuberculin antigens. Associations with HIV status and CD4+ lymphocyte levels were analyzed. Results: Candida, mumps, and tetanus antigens alone or in combination elicited reactions significantly less often in HIV-seropositive than in HIV-seronegative women and less often in seropositive women with lower CD4+ counts, regardless of induration cutpoint chosen to define a positive reaction. The best antigen combinations for distinguishing groups included tetanus and mumps. Some women nonreactive to the 3 antigens ('anergie') had positive tuberculin reactions among both seropositive subjects (range, 1.1% to 2.9% depending on induration cutpoint for defining anergy) and seronegative subjects (range, 8.9% to 14%). Conclusion: Absence of reactions to Candida, mumps, and tetanus antigens alone or in combination and at any induration cutpoint is associated with HIV status and with CD4+ level. Combinations, including tetanus and thumps antigens with an induration cutpoint of less than 2 mm, may be the best for defining anergy.