Use of different saprophytic acid-fast bacilli in complement-fixation test for kala-azar

Complement-fixation tests for kala-azar using antigenic extracts from 4 different saprophytic acid fast bacilli were carried out. It was observed that all the 4 extracts gave positive reactions with sera from kala-azar patients. However, Myco. phlei gave best results and next comes Kedrowsky's bacilli. These two are different strains of the same organism, Myco. phlei. Myco. smegmatis also gave satisfactory results but Myco. butyricum gave weak and false negative reactions in some cases. Last two organisms are the different strains of the same Myco. smegmatis.