Evaluation of Hemolytic Modification of Middlebrookdubos Test for Tuberculous Antibodies

Abstract

The hemolytic modification of the Middlebrook-Dubos test yielded less than 1.5% positive results in 226 non-tuberculous persons. Of 47 individuals with negative Middlebrook tests, 17 revealed titers up to 1:8 after tuberculin skin tests. In some instances the serol. test became positive although the first skin test remained negative, and only a 2d skin test performed 2 weeks later showed a positive reaction. Of 35 tests on patients with moderately advanced pulmonary tuberculosis 66%, and of 61 far-advanced cases 36% were negative. The titer remained fairly constant and seemed to be independent of the course of the disease. Antibodies were also demonstrated in pleural fluid. Pretreatment of sheep red blood cells with Forssman antibody enhanced the sensitivity of the test.