882 



MANUAL OF DETERMINATIVE BACTERIOLOGY 



32; Nord. Med. Ark., 12, 1880, 1; Quart. 

 Jour. Micro. Sci., 20, 1880, 92; Coccothrix 

 leprae Lutz, Dermatol. Stud. 1, 1886, 

 quoted from DeToni and Trevisan, in 

 Saccardo, Sylloge Fungorum, 8, 1889, 

 944; Lehmann and Neumann, Bakt. 

 Diag., 1 Aufl., 2, 1896, 372; Discomyces 

 leprae Neveu-Lemaire, Precis Parasit. 

 Hum., 5th ed., 1921, 27; Sclerothrix 

 leprae Vuillemin, Encyclopedic Mj'co- 

 logique, Paris, ^, 1921, 135; Mycobacterium 

 leprae hominus Lowe, Internat. Jour. 

 Leprosy, 5, 1937, 312.) From Greek 

 lepra, leprosy. 



Common name: Leprosy bacillus. 



Armauer-Hansen Hoc. cit.) was the first 

 to observe the bacilli in the tissues of 

 lepers. The disease is now known as 

 Hansen's disease. The bacilli occur in 

 enormous numbers in lepromatous (nod- 

 ular) cases of the disease and sparsely 

 in the neural form. The present bac- 

 teriological means of identification de- 

 pend on: (a) acid-fast staining, and (b) 

 failure of the organism to grow in bac- 

 teriological media or in laboratory 

 animals. Heated suspensions of the 

 bacilli (obtained from nodules) produce 

 a positive lepromin reaction in 75 to 97 

 per cent of normal persons and of neural 

 cases of leprosy, but usually produce 

 no reaction in lepromatous individuals 

 (Mitsuda: See Hayashi, Int. Jour. 

 Leprosy, /, 1933, 31-38). The failure of 

 lepromatous persons to respond to in- 

 jected leprosy bacilli constitutes a 

 fundamental criterion for testing the 

 validity of microorganisms such as other 

 acid-fast or diphtheroid cultures which 

 can at times be recovered from leprous 

 tissues by inoculation of bacteriological 

 media. 



Many organisms have been isolated 

 from leprous tissues, some of which are 

 acid-fast and have been styled Myco- 

 bacterium leprae. The strains which 

 have been adequately studied have 

 proven to fall into the saprophytic 

 groups (see No. 11, Mycobacterium, spp.) 

 Hanks (Int. Jour. Leprosy, 9, 1941, 275- 

 298) found that acid-fast cultures of this 



type, as well as the diphtheroids which 

 also have repeatedly been isolated from 

 leprosj% were recoverable only from 

 lesions located proximally with respect 

 to open ulcers in the skin. 



Description of organisms seen in 

 leprosy tissue from Armauer-Hansen 

 {loc. cit.) and Topley and Wilson (Prin- 

 cip. Bact. and Immun., 2nd ed., 1936, 

 316). 



Rods : 0.3 to 0.5 by 1 to 8 microns, with 

 parallel sides and rounded ends, staining 

 evenly or at times beaded. When nu- 

 merous, as from lepromatous cases, they 

 are generally arranged in clumps, 

 rounded masses or in groups of bacilli 

 side by side. Strongly acid-fast. Gram- 

 positive. 



Pathogenicity : The communicability 

 of leprosy from man to man is accepted 

 (Rogers and Muir, Leprosy, 2nd ed., 

 Baltimore, 1940, 260 pp.). Experimental 

 transmission to humans or to animals 

 has not been successful. 



Source: Human leprous lesions. In 

 the lepromatous form of the disease 

 bacilli are so abundant as to produce 

 stuffed-cell granulomas; in the tubercu- 

 loid and neutral lesions they are rare. 



Habitat: Obligate parasite in man. 

 Confined largely to the skin (especially 

 to convex and exposed surfaces) and to 

 peripheral nerves. The microorganisms 

 probably do not grow in the internal 

 organs. 



5. Mycobacteriun lepraemuriiun Mar- 

 choux and Sorel. (Bacillus der Ratten- 

 lepra, Stefanskj^, Cent. f. Bakt., I Abt., 

 Orig., 33, 1903, 4S1 ; Mycobacterium leprae 

 murium Marchoux and Sorel, Ann. Inst. 

 Past., 26, 1912, 700; Bacillus leprae mu- 

 rium Muir and Henderson, Indian Jour. 

 Med. Res., 15, 1927, 15.) 



Mycobacterium pulviforme Marchoux 

 (Ann. Derm., 1921, No. 21 and Ann. 

 Inst. Past., 37, 1923, 348) from leprosy- 

 like lesions in a man from Hayti is 

 thought by the author to be identical 

 with Mycobacterium lepraemurium. 



Common name: Rat leprosy bacillus. 



