302 LEPROSY 



also found in spindle-shaped connective-tissue cells, in endothelial 

 cells, and in the walls of blood vessels. They are for the most 

 part confined to the connective tissue, but a few may be 

 seen in the hair follicles and glands of the skin. Occasionally 

 one or two may be found in the surface epithelium, where they 

 probably have been carried by leucocytes, but this position is, on 

 the whole, exceptional. They also occur in large numbers in the 

 lymphatic glands associated with the affected parts. In the 

 internal organs, liver, spleen, etc., when leprous lesions are 

 present, the bacilli are also found, though in relatively smaller 

 numbers. In the nerves in the anaesthetic form they are com- 

 paratively few, and in the sclerosed parts it may be impossible to 

 find any. There are few also in the skin patches referred to 

 above as occurring in this form of the disease. 



Their spread is chiefly by the lymphatics, though distribution 

 by the blood stream also occurs. They are said to have been 

 found in the blood during the presence of fever and the eruption 

 of fresh nodules, and they have also been observed in the blood 

 vessels post mortem, chiefly contained within leucocytes. Recent 

 observations (e.g. those of Doutrelepont and Wolters) show that 

 the bacilli may be more widely spread throughout the body than 

 was formerly supposed. A few may be detected in some cases 

 in various organs which show no structural change, especially in 

 the capillaries. The brain and spinal cord are almost exempt, 

 but in some cases bacilli have been found even within nerve 

 cells. 



Eelations to the Disease. Attempts to obtain pure cultures 

 of the leprosy bacillus have so far been unsuccessful. Clegg has 

 recently attempted to grow the organism in association with 

 amoebae and other bacteria on agar plates, and has obtained a 

 short acid-fast bacillus which does not grow on ordinary media, 

 and which has been carried through several generations in the 

 conditions mentioned. The identity of this organism with the 

 leprosy bacillus has, however, not been established. Attempts 

 to transfer the disease to animals, including monkeys, have been 

 unsuccessful. When a small portion of leprous material is 

 transplanted, a nodule may result in which leprosy bacilli may be 

 demonstrated for some time, but this probably represents merely 

 the reaction to a foreign body ; there is no sufficient evidence 

 that the bacilli undergo multiplication, and it is impossible to 

 continue such lesions in fresh animals. The only exception to 

 this statement is afforded by the experiments of Melcher and 

 Orthmann, who inoculated the anterior chamber of the eye of 

 rabbits with leprous material, the inoculation being followed by 



