164 TROPICAL MEDICINE AND HYGIENE 



cells of the capillaries and lymphatics, and are also met 

 with in free mononuclear cells, but do not occur in 

 the liver cells themselves. Haemosiderin is present both 

 in the hepatic cells and in the spleen pulp. 



Next to the spleen and liver the bone-marrow and 

 lymphatic glands are the principal seats of the parasites, 

 which occur chiefly in the large mononuclear cells ; the 

 marrow appears to be increased in amount and is redder 

 than normal. 



Should death have been brought about by dysentery, 

 as is so commonly the case, the large intestine will be 

 found thickened and inflamed, the descending colon and 

 sigmoid flexure being chiefly affected. The inflammation 

 sometimes affects the whole length of the large intestine, 

 and may involve the lower part of the small intestine. 

 There is great inflammatory infiltration of all the coats 

 of the bowel, and frequently there are ulcers extending 

 from the mucous to the serous coat, or even causing per- 

 foration ; sometimes the mucous membrane is covered 

 with a tough film of exudation. 



The inflammation of the intestine does not appear to 

 be directly due to the Leishman body, for but few of 

 these organisms are usually found in its coat ; they occur 

 chiefly in the endothelial cells of the capillaries. 



In uncomplicated cases the other organs of the body 

 appear to be healthy, but even in this case parasites may 

 be found, though sparingly, in the endothelial cells of 

 the capillaries and lymph spaces of various organs, e.g., 

 lungs, kidneys, suprarenal capsules, and lymphatic glands. 

 Sometimes the mesenteric glands are enlarged, and 

 contain the specific parasites in large numbers. In spite 

 of the wide distribution of the parasite in the body it 

 has never been found in any of the secretions or excre- 

 tions during life. The difficulty of finding the organism 

 in the blood has already been alluded to. 



In fresh unstained preparations the parasites of kala- 

 azar are difficult to see. They appear as rather refractile, 

 motionless bodies of indefinite outline, almost colourless 



