568 KALA-AZAR 



malarial parasites from the blood, and the features of the 

 leucopenia which have been alluded to. 



Delhi Sore. In various tropical and sub-tropical regions 

 there is widely prevalent a variety of very intractable chronic 

 ulceration which goes by various names in different parts of 

 the world, Delhi sore, tropical ulcer, Aleppo boil, etc. Various 

 views have been held as to the pathology of the condition, but 

 the work of J. H. Wright, which has been confirmed by other 

 observers, makes it extremely probable that a protozoal parasite 

 is concerned in its etiology. In the discharge from the ulcer 

 and in sections of a portion of tissue excised from a case coming 

 from Armenia, Wright observed great numbers of round or oval, 

 sharply defined bodies, 2-4 //. in diameter. When stained by a 

 Komanowsky combination there was found to be a peripheral 

 portion coloured a pale blue and a central portion tending to be 

 unstained ; there were also two chromatin bodies, one larger, 

 occupying a fourth or a third of the whole and situated in the 

 periphery, another smaller, round or rod-shaped, and of a deeper 

 colour than the larger mass. It was found that the bodies 

 were usually intra-cellular in position in the lesion, as many as 

 twenty being in one cell, and that the type of cell containing 

 them was, as in kala-azar, that derivable from endothelial tissues. 



There can be little doubt that these bodies are of the same 

 type as those occurring in kala-azar, and the question of the 

 identity of the two parasites has been raised. At present the 

 tendency is to regard them as distinct. As we have seen, 

 although skin ulcers are common in kala-azar, it is difficult to 

 find the parasite in this lesion of the disease, while, on the 

 other hand, in Wright's case at least the number of organisms 

 present in the ulcer was enormous. Provisionally Minchin 

 calls this parasite the Leishmania tropica and includes it as the 

 second species of the genus Leishmania. 



PIROPLASMOSIS. 



Up to the present no human disease has been proved to be associated 

 with the presence of piroplasmata. The observations of Donovan, 

 which seemed to indicate that the parasite of kala-azar might be found 

 within the red blood corpuscles, and which led Laveran to denominate 

 the Leishmania donovani the piroplasma donovani, have, as already 

 indicated, not been confirmed ; the same is true of the association of 

 piroplasms with the occurrence of the Rocky Mountain spotted fever 

 sometimes prevalent in Montana. But several important diseases of the 

 lower animals are almost certainly caused by protozoan parasites of this 

 group, and a short account of the organisms may be given. 



The piroplasmata are pear-shaped unicellular organisms about 1-1 '5 ju, 



