Precipitin Tests with Phosphatide Fractions of Tubercle Bacilli *

Many types of precipitin test for tuberculosis based on the use of tuberculin and various extracts have been developed by previous investigators. In general these tests have been unsatisfactory because of their lack of specificity. In 1929 Doan' reported a precipitin test for tuberculosis in which the phosphatide fraction isolated from the tubercle bacillus by Anderson2 was used. His results indicated that the test was of considerable diagnostic value. Employing essentially the method developed by Doan3, we have made a series of tests on material obtained from 233 patients. In this study, tests were made with phosphatide antigenic dilutions only; no antiphosphatide serum was used. The phosphatide fractions used were kindly supplied by the H. K. Mulford Company and were listed by them as follows: