The effect of immunodeficiency on cutaneous delayed-type hypersensitivity testing in HIV-infected women without anergy: implications for tuberculin testing

SETTING: A collaborative study in four urban medical centers in the United States. OBJECTIVE: To determine the effect of human immunodeficiency virus (HIV) infection and immunodeficiency on delayed type hypersensitivity (DTH) responses and the implications for interpretation of tuberculin reactions in non-anergic women with or at risk for HIV infection. DESIGN: Demographic and behavioral information, HIV antibody testing, CD4+ lymphocyte counts, and cutaneous responses to DTH testing with mumps, Candida, tetanus toroid, and tuberculin (purified protein derivative-PPD) antigens were obtained in 1184 women. RESULTS: Reactions to one or more of the four antigens occurred in 436 HIV-seropositive and 356 high-risk seronegative women. Among non-anergic women, HIV-seropositives were less likely (P less than or equal to 0.05) to react to mumps (62% vs 81%), tetanus (72% vs 84%), and PPD (13% vs 19%). Induration in HIV-seropositive reactors was associated with CD4+ cell level for mumps (P = 0.004) and tetanus (P < 0.001), but not for Candida or PPD, HIV-seropositive reactors with CD4+ cell counts >500/mm(3) did not have significantly smaller reactions than HIV-seronegatives for any antigen tested. PPD sizes were similar among HIV-seropositive reactors with CD4+ cell counts >500/mm(3) (12.4 +/- 7.4 mm) and HIV-seronegative reactors (12.0 +/- 8.3 mm); induration greater than or equal to 10 mm was seen in 16/173 (9.2%) seropositive women with CD4+ cell counts >500/mm3 and 41/356 (11.5%) seronegative women, respectively (P = 0.5). CONCLUSION: Among HIV-infected women able to react to a DTH antigen, induration in response to that antigen was relatively intact at CD4+ counts >500/mm3. This suggests that degree of immunodeficiency should be considered when interpreting PPD reactions in HIV-infected persons.