518 A MANUAL OF BACTERIOLOGY 



examined, there is an abundant formation of gas, par- 

 ticularly in the liver, which is riddled with gas bubbles. 

 Monkeys fed with considerable numbers of B. perfringens 

 are unaffected. Agglutinins do not seem to be formed by 

 this organism. 



B. perfringens is the principal cause of gas gangrene 

 in man. The condition arises subsequent to a wound, 

 within a period from a day or two up to tw r o or three weeks 

 after infliction. The tissues become hard, tense and cre- 

 pitant, gangrene ensues which may be limited to a muscle 

 or group of muscles or even to an area of skin or may 

 spread widely, a repulsive sickening odour emanates from 

 the patient, who in the bad cases rapidly passes into a state 

 of profound toxaemia and death may ensue within twenty- 

 four to forty-eight hours. 



The mode of action of B. perfringens has been the 

 subject of discussion. Wright holds that B. perfringens 

 induces an acidsemia whereby the antitrypsin is diminished 

 and the organisms are then able to multiply explosively. 

 Bull and Pritchett 1 hold the view, which must be 

 regarded as the correct one, that infection by B. per- 

 fringens, like infection by B. tetani, essentially resolves 

 itself into an intoxication, in which an exotoxin yielded 

 by the multiplying organisms constitutes the chief 

 danger. 



Although the organism is so deadly in many cases, it 

 may be present in enormous numbers without gas gan- 

 grene ensuing. Emery 2 attributes this difference largely 

 to the influence of the toxin upon leucocytic emigration. 

 Provided the amount of toxin is not too great, leucocytes 

 emigrate in numbers and by their phagocytic action are 

 protective ; if however the toxin becomes concentrated, 

 leucocytes no longer emigrate. Concentration of toxin 



1 Journ. Exper. Med., vol. xxvi, 1917, p. 119. 



2 Lancet, 1916, vol. i, p. 948. 



