2-STAGE TUBERCULIN SKIN TESTING IN INDIVIDUALS WITH HUMAN-IMMUNODEFICIENCY-VIRUS INFECTION

In this study we estimated occurrence of the booster effect in a popul ation infected with the human immunodeficiency virus (HIV) and assesse d the relation between the booster effect, T-lymphocyte CD4 cell count s, tuberculosis risk categories, and HIV exposure categories. Patients were recruited from 13 participating sites of the Terry Beirn Communi ty Programs for Clinical Research on AIDS (CPCRA). A two-stage tubercu lin skin test was applied to 709 HIV-infected patients using the Manto ux method. An induration reading < 5 mm on the first test and greater than or equal to 5 mm on the second skin test defined the booster effe ct. Overall, 18 patients, or 2.7% (95% confidence interval, 1.6 to 4.2 ) experienced the booster ef feet. Boosted responses were seen in eigh t (2.1%) anergic patients, six (4.5%) nonanergic patients, and four (2 .5%) with anergy status unknown. Boosting was noted in 1 of the 131 wo men enrolled. Age, race, CD4 cell count, injection drug use, anergy st atus, tuberculosis risk categories, and HIV exposure categories were n ot predictive of boosting. The booster effect occurs in a small percen tage of HIV-infected patients tested, thus identifying small numbers o f patients with latent tuberculosis infection. The two-stage procedure is probably of limited value in the diagnosis of latent tuberculosis in HIV-infected persons.