Goldstein S, Perlman D C, Salomon N
Division of Chemical Dependency and Infectious Diseases, Beth Israel Medical Center, New York, NY 10003.
Mt Sinai J Med. 1994 Sep;61(4):337-40.
To identify differences in purified protein derivative (PPD) tuberculin positivity rates and to assess the utility of sequential PPD testing among persons with HIV infection, we performed two sequential administrations of 5 tuberculin units of PPD in a group of persons with HIV infection. Eligible patients were skin-tested with the tuberculin using the Mantoux method. Patients who tested < 5 mm of induration were skin-tested seven days later along with Candida and mumps antigens. Of 37 tested patients, only 18 (49%) returned to have the first test read. Using a > or = 5 mm cutoff, 5 (28%) tested positive. Positivity varied markedly between patients with CD4+ cell counts under and at or over 400 cells/mm3 (0% vs. 56%). Among patients who had a reaction to the first test, the reaction was smaller in patients with CD4+ cell counts under 400 than in those with counts at or over 400 cells/mm3 (mean induration: 2.8 vs. 30.4 mm). Positivity was also less frequent in intravenous drug users than in nonusers (9% vs. 57%); these two groups did not differ with respect to CD4+ cell counts. Of the 13 patients who tested < 5 mm, only 8 (62%) kept their appointments to have the second test placed and read. Only 1 of these, a drug user with a CD4+ count of 6 cells/mm3, had a positive reaction with boosting from 4 mm on the first test to 10 mm on the second. These data indicate that PPD testing may be unreliable in screening for tuberculosis infection in persons with CD4+ counts < 400 cell/mm3.(ABSTRACT TRUNCATED AT 250 WORDS)
