TROPICAL KALA-AZAR 



1293 



bone-marrow, as well as the ulceration of the skin and intestinal 

 mucosa, because sometimes, and in an inconstant manner, it can 

 produce a reaction on the part of the body, as is seen in the formation 

 at times of agglutinins, specific precipitins, inconstant in presence 

 and feeble in action, and useless from a diagnostic point of view, 

 as is complement deviation. At the commencement of the infection 

 there appears to be generally an attempt to produce an immunity, 

 and it is this which produces the rare natural cure in man. It may 

 be the cause of the refrac- 

 tory nature of certain . . t 

 animals to the disease and 

 the limitation of infection 

 in endemic communities. 

 After the infection has 

 obtained its hold on the 

 body as a rule the struggle 

 for immunity becomes less 

 and less, and disappears 

 eventually. 



By some means or other 

 the parasite irritates the 

 organ it infects, causing 

 marked changes in the 

 spleen, liver, and bone- 

 marrow, and also causing 

 ulceration of the intestine 

 and skin. 



The Blood.— The exam- 

 ination of the blood is 

 most important because, 

 firstly, the parasite may be 

 found in a leucocyte if 

 carefully looked for, even 

 in the early stages of the 

 disease; secondly, the leu- 

 cocytic changes are of the 

 utmost importance. There 

 is marked anaemia — 54*2 

 per cent, of Rogers' cases 

 giving from 4,000,000 to 

 2,500,000 corpuscles per 



cubic millimetre — and the haemoglobin is reduced in propor- 

 tion to the erythrocytes, the colour-index being normal. There 

 is a most marked leucopenia, and Rogers reports that in 42-1 per 

 cent, of his cases the leucocytes were 1,000 or less, in 3o«3 per 

 cent. 1,000 to 2,000, and in 22*6 per cent. 2,000 to 3,000. The 

 proportion of white to red, according to the same author, is 

 less than i : 1,500 in 67-9 per cent., or, if inflammatory cases are 

 excluded, in nearly 90 per cent, of the cases he examined. There 



Fig. 644. — Indian Kala-Azar. 



The distension of the abdomen by the 

 greatly enlarged spleen should be noted. 

 (Photograph of a case in the Tropical 

 Clinic, Colombo.) 



