MORPHOLOGY 351 



moto claims that the leprosy bacillus can be differentiated from the tubercle 

 bacillus in films. 



Fix the film in the flame, treat for 10 minutes in a bath of 5 per cent, 

 solution of silver nitrate at 55-60 C. and then transfer to the reducing 

 solution : 



Pyrogallol, - 2 -grams. 



Tannin, - 1 gram. 



Distilled water, - 100 c.c. 



Tubercle bacilli are stained black : leprosy bacilli are unstained and may 

 be counter-stained by carbol-fuchsin. 



[B. In cultures. Rost found acid-fast bacteria massed together in parallel 

 arrangement in his cultures from leprous nodules on milk-fish broth. When 

 sub-cultivated on agar and broth a feebly acid-fast bacillus developed and it 

 was found that the acid-fastness could be increased by growing the organism 

 on milk. The organism is highly pleomorphic. In sub-cultures after 48 

 hours' incubation the appearance is the same as in the nodules of a leper. 

 In older cultures or when grown under unfavourable conditions " degenerate 

 forms are found which double or treble their usual length with a moniliform 

 arrangement and lose their acid-fastness. These break down after a few 

 days into clumps of small acid-fast coccoid forms." 



[Bayon cultivated from cases of human leprosy an acid-resisting diphtheroid 

 organism which acquired acid-fast properties on being inoculated into rats 

 and mice. 



[Williams grew a very pleomorphic streptothrix from the lesions of human 

 leprosy " which in addition to changes in form exhibited marked changes 

 in its staining reactions in regard to the quality known as acid-fastness." 

 Williams describes the following forms : 



(a) On broth media and on potato-broth a non-acid-fast streptothrix in the 

 mycelial stage which produced acid-fast rods. 



(ft) On milk and lemco-broth a non-acid-fast diphtheroid bacillus which also 

 produced acid -fast rods. 



(y) On Rost's medium an acid-fast bacillus which is but the broken-down stage 

 of a streptothrix, and 



(8) On Dorset's egg medium an acid-fast mycelium. This streptothrix which 

 was cultivated from a leper passed through respectively all the stages described 

 above. ] 



2. Cultures. 



Very little is yet known about the cultivation of the leprosy bacillus. 

 Roux, Cornil, and Chantemesse failed in their attempts to grow the bacillus : 

 numerous observers have obtained cultures after sowing pieces of leprous 

 tissues, but in the great majority of cases these were cultures of organisms 

 of secondary infection and not cultures of the leprosy bacillus (vide infra). 



Bordoni-Uffreduzzi for example described certain growths as cultures of the 

 leprosy bacillus which were obviously cultures of the tubercle bacillus : similarly 

 Neisser's cultures were not cultures of the leprosy bacillus. Babes' cultures were 

 cultures of a bacillus which did not stain either with Ehrlich's or Ziehl-Neelsen's 

 stain : apparently also Ducrey's anaerobic organism may be dismissed without 

 consideration. 



Czaplewski, Spronck, Teich, Levy, Rost and others seem to have grown 

 cultures of the leprosy bacillus, though it is to be noted that the descriptions 

 of their cultures do not at all coincide. 



Spronck sowed leprous bone marrow and non-ulcerated leprous nodules on neutral 

 glycerin-potato : the growth was said to have been sub -cultivated on coagulated 

 serum, glucose-glycerin-agar and glycerin- fish -broth (p. 319) but not on glycerin- 

 potato. Growth took place at 25 C. and was copious at 37 C. 



