CHAPTEE XXIX. 



LEPROSY. — SYPHILIS. — EHINOSCLEROMA. — TRACHOMA. 



Leprosy. 



Leprosy occurs in three forms — tubercular, anaesthetic, and mixed 

 tubercular. It may be classed with the granulomata, as the most 

 common form of the disease is characterised by deposits in the skin, 

 mucous membrane, and internal organs. These deposits are composed 

 of small cells, and large cells resembling giant cells. The cells 

 become deposited in the surrounding tissues, and so the tubercle 

 enlarges, involving the epidermis and developing into an ulcerating 

 sore ; or, after a certain stage of development, beginning to decline, 

 and finally leaving a puffy discoloration. In the anaesthetic form 

 the cells invade the connective tissue of nerves. In the mixed 

 form the varieties occur together, but the tubercular character 

 predominates. 



Tuberpular leprosy commences with the development of an 

 erythematous patch, which becomes infiltrated, and finally tubercu- 

 lated, the tubercles varying in size from a millet seed to a marble, 

 or even larger. The eruption on the head and face produces a 

 characteristic leonine expression. The progress of the disease is very 

 slow. After death the following changes may be found in the 

 internal organs : Ciri'hosis of the liver and spleen, enlargement of 

 the lymphatic glands, and a condition of the lungs corresponding 

 to cheesy bronchial pneumonia. 



In the anaesthetic form patches develop on the skin, which 

 become anaesthetic ; ulceration follows, and the fingers and to§s, or 

 the entire hand and foot, may slough off. 



The disease is undoubtedly communicable, but the infectivity is 

 of a very low type. 



The infectiousness is illustrated by the well-known case of Father 

 Damien. Arning inoculated a man named Keanu, a condemned 

 criminal,, and leprosy developed three years afterwards, but this case 



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