466 LEPROSY AND ACID-FAST BACTERIA 



nodule or tumor is produced. If the seat of infection is a nerve, 

 a spindle-shaped thickening is produced about the nerve, which 

 causes pressure, irritation, inflammation, degeneration, and, finally, 

 atrophy, which leads to anesthesia of the area of distribution of the 

 nerve. The bacilli are found both in the neuroglia and in nerve cells, 

 particularly the ganglion cells. When the cell is thus infected it under- 

 goes degeneration, sometimes accompanied by swelling and formation 

 of vacuoles. If the bacilli become attached to arteries a proliferating 

 inflammation results which causes the walls of the vessel to become 

 greatly thickened and the lumen narrowed. 



The disease often displays a selective action for the skin, especially 

 in the face, the extensor surfaces of the nose and elbows, and on the 

 backs of the hands and feet. These areas are very apt to undergo 

 ulcer at ion. The organism makes its appearance in the skin by pro- 

 ducing red spots which either disappear, leaving pigmented areas, or 

 become elevated in nodules of a brown-red color. In the region of 

 these nodules the subcutaneous tissues contain large numbers of 

 bacilli. These eruptions are probably to be regarded as general 

 inflammatory reactions in response to the irritation produced by the 

 bacillus. The nodules may remain small and hard, or they may 

 become enlarged, in which case large protuberances appear which 

 destroy the symmetry of the face and give the victim a lion-like 

 appearance, hence the name facies leontina. 



Animal. It must be remembered that tubercle bacilli are very 

 frequently found in lepers; in fact, a not inconsiderable number of 

 lepers die of tuberculosis rather than leprosy. Consequently it is 

 not surprising to find that many experiments on animals have resulted 

 in the production of lesions from which acid-fast bacilli have been 

 obtained. These experiments must be interpreted with a great deal 

 of caution for this reason. Nicolle 1 claims to have successfully infected 

 a monkey (Macacus) with leprous material. Lesions appeared which 

 were nodular in character, but they disappeared spontaneously 

 within six months. The result is questionable and successful inocula- 

 tions of leprosy bacilli from lepra nodules into the lower animals are 

 not definitely proven as yet. 



Portal of Entry. Leprous lesions appear early and are fairly constant 

 in the nasal passage, where an ulcer appears at the junction of the 

 bony and cartilaginous septum. This has given rise to the belief 

 that the nasal passages are the chief portals of entry of the organism 



1 Semaine Medicale, 1905, 110. 



