Purified protein derivative tuberculin and delayed-type hypersensitivity skin testing in migrant farm workers at risk for tuberculosis and HIV coinfection

Abstract

In this population with 5% HIV seroprevalence, testing for anergy did not significantly increase the detection of preventive therapy eligibility. The use of two DTH antigens is very sensitive and specific. These results support the recommendation of joint PPD and anergy testing for the screening of HIV-seropositive individuals. Our data also suggest, however, that for individuals whose HIV serostatus is unknown, anergy testing should be considered as a screening tool only if the prevalence of anergy is expected to exceed the prevalence of PPD positivity.