334 A MANUAL OF BACTERIOLOGY 



as obtained from the tissues is non-motile, stains readily 

 with the ordinary anilin dyes, and by Gram's method, 

 which brings out the beaded appearance very well, and is 

 markedly acid-fast, thus closely resembling the tubercle 

 bacillus, and the methods used to demonstrate it are the 

 same as for the latter organism. 



The Bacillus leprce is found in enormous numbers, 

 usually crowded together in bundles or masses, in the 

 leprous nodules in the skin (Plate X. a), liver, spleen, and 

 testicles, in the affected nerves in the anaesthetic form 

 and even in the ganglion cells of the central nervous system 

 in fact, any viscus may be affected ; it has also been 

 found in the blood, but only in the febrile paroxysms 

 which set in when the disease is approaching a fatal 

 termination. The exact situation of the leprosy bacilli 

 in the tissues has been a matter of controversy. By some 

 it has been held that they are contained within certain 

 round cells, the so-called leprous cells, and this may be 

 the case, but to an inconsiderable extent. Unna has 

 always regarded these leprous cells as really being trans- 

 verse sections of lymphatic vessels containing bacillary 

 thrombi, and this seems to be usually the case. Giant- 

 cells are occasionally present in the leprous nodules. One 

 of the most constant and earliest situations in which the 

 B. leprce is found is the nasal mucous membrane. 



Lepers react to the old tuberculin and also give the 

 Wassermann reaction. 



Although the organism is present in such enormous 

 numbers and is so readily demonstrable, to cultivate it 

 on artificial media and to infect animals with it are both 

 difficult matters. Babes, Bordoni-Uffreduzzi, Czaplewski, 

 are some of those who in the past believe that they have 

 cultivated the leprosy bacillus. Van Houten 1 claimed to 

 have succeeded by growing it in glycerin fish broth. The 



1 Journ. Path, and BacL, vol. viii, 1903, p. 260. 



