The Value of the Complement-Fixation Test in the Diagnosis of Kala-Azar

In a previous publication (Sen Gupta, 1943), the results of the complement-fixation test using the original Witebsky, Klingenstein, Kuhn (WKK) antigen were reported. Reference was also made about the preparation of the antigen according to the WKK method. It was shown that a complement-fixation test of marked degree of ' specificity' for kala-azar had been evolved. In order to investigate further the value of the complement-fixation test in the diagnosis of kala-azar, it was decided during last year to include this test in the routine investigation of all cases referred to the kala-azar out-patients clinic or the kala-azar research department of the Calcutta School of Tropical Medicine. The antigen used in this investigation was not, like the original WKK antigen, prepared from the human tubercle bacillus. The work of Dharmendra and Bose (1941) had shown that with antigens prepared from various acid-fast bacilli, viz Mycobacterium phlei and the socalled leprosy bacilli of Kedrowsky, Lleras, Bayon and Duval, complement-fixation reaction similar to that with the original WKK antigen could be obtained in leprosy and in leishmaniasis. Due to some practical difficulties in obtaining adequate quantities of growth of the human tubercle bacillus, it was decided to use