EMPHYSEMATOUS GANGRENE 427 



Bacillus botulinus 



In certain forms of meat poisoning (see Chap. XXI) van 

 Ermengem isolated an anaerobic bacillus, the B. botulinus. It 

 is chiefly met with in ham and sausage, and the symptoms are 

 caused by the absorption of toxin, which has a special effect on the 

 nerve centres. 



The organism is a large Gram-positive sporing anaerobic bacillus, 

 often occurring in pairs or in short chains. In glucose gelatin it 

 forms a whitish streak in the line of the stab, with lateral out- 

 growths, liquefaction of the medium, and gas-formation. The 

 cultures have a rancid odour, due to butyric acid production. The 

 colonies in gelatin are semi-transparent spheres. The optimum 

 growth is from 20-30 C. The source of the organism is unknown, 

 but it has once been isolated from the excreta of a healthy pig. 



The B. botulinus in broth cultures forms a potent extra-cellular 

 toxin, which is toxic both by injection and by ingestion. The toxin 

 is also produced in the infected ham, sausage, etc. With the toxin 

 an antitoxin can be prepared. 



Bacillus Welchii * 



Probable synonyms. B. aerogenes capsulatus (Welch and Nuttall), 

 Granulo -bacillus saccliaro-butyricus immobilis liquefaciens (Grass- 

 berger and Schattenfroh), B. enteritidis sporogenes (Klein), B. per- 

 fringens (Veillon and Zuber), gasphlegmon bacillus (Frankel). 

 bacillus of acute rheumatism (Achalme : see " Rheumatism "). 



This organism was originally described by Welch and 

 Nuttall under the name B. aerogenes capsulatus, and 

 occurs in conditions accompanied by much development 

 of gas in the tissues, as in cases which might be described 

 either as phlegmonous erysipelas or as emphysematous 

 gangrene, especially after injuries. It is also met with 



1 See Welch and Nuttall, Bull. Johns Hopkins Hosp., vol. iii, 1892, 

 p. 81 ; Welch, ' Shattuck Lecture,' ibid. vol. xi, 1900, p. 185 ; Dunham, 

 ibid. vol. viii. 1897, p. 68 ; Welch and Flexner, Journ. Exper. Med., 

 vol. i, 1896, p. 5 ; Herter, Bacterial Infections of the Digestive Tract, 

 1907 ; Kamen, Centr. f. Bakt., Orig. xxxv, 1904, pp. 554, 6S6 ; Archiv. 

 f. Hyg., vol. liii, 1905, p. 128 ; and Blake and Lahey, Journ. Amer. 

 Med. Assoc., vol. liv, 1910, p. 1671. 



