CHAPTER X. 



LEPROSY. 



LEPROSY is a disease of great interest, alike in its clinical and 

 pathological aspects ; whilst from the bacteriological point of 

 view also, it presents some striking peculiarities. The invariable 

 association of large numbers of characteristic bacilli with all 

 leprous lesions is a well-established fact, and yet, so far, attempts 

 to cultivate the bacilli outside the body, or to produce the disease 

 experimentally in animals, have been attended with failure. 

 Leprosy, so far as is known, is a disease which is confined to the 

 human subject, but it has a very wide geographical distribution. 

 It occurs in certain parts of Europe Norway, Russia, Greece, 

 etc., but is commonest in Asia, occurring in Syria, Persia, etc. 

 It is prevalent in Africa, being especially found along the coast, 

 in the Pacific Islands, in the warmer parts of North and South 

 America, and also to a small extent in the northern part of North 

 America. In all these various regions the disease presents the 

 same general features, and the study of its pathological and 

 bacteriological characters, wherever such has been carried on, has 

 yielded similar results. 



Pathological Changes. Leprosy is characteristically a chronic 

 disease, in which there is a great amount of tissue change, with 

 comparatively little necessary impairment of the general health. 

 In other w^ords, the local effects of the bacilli are well marked, 

 often extreme, whilst the toxic phenomena are proportionately at 

 a minimum. 



There are two chief forms of leprosy. The one, usually called 

 the tubercular form lepra tuberosa or tuberculosa is character- 

 ised by the growth of granulation tissue in a nodular form or as a 

 diffuse infiltration in the skin, in mucous membranes, etc., great 

 disfigurement often resulting. In the other form, the anaesthetic, 

 maculo- anaesthetic of Hansen and Looft the outstanding 



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