CHAPTER VI. 



BACTERIAL POISONS.* 



There are now recognized three different kinds of bacterial 

 poisons: (a) Ptomaines, or poisons produced by bacteria out 

 of the medium upon which they grow; (b) endotoxions, or 

 poisons contained within the bacterial cell and liberated only 

 upon the disintegration of the cells ; (c) toxins, or poisons liber- 

 ated into the culture-medium and into the animal body by 

 the bacteria during their growth, probably as a sort of excretory 

 product. The ptomaines are not specific, they are not pro- 

 duced necessarily by pathogenic bacteria, but, as the name 

 implies, may be developed in putrefying meat. These bodies 

 were first studied by Brieger. They are crystalline in charac- 

 ter. On the other hand, it is now generally accepted that in 

 most, if not all of the infectious diseases, the principal symptoms 

 and lesions are to be attributed to the action of either endo- 

 toxins or of toxins. Even in those cases where poisonous sub- 

 ..stances are not demonstrable in cultures or demonstrable with 

 difficulty only, there is reason to believe that the bacteria in 

 such cases may, nevertheless, produce poisons in the animal 

 body. 



Certain infectious diseases afford examples of poisoning by 

 bacterial products in an extremely marked manner. In teta- 

 nus the local wound may be trifling and in itself utterly inca- 

 pable of giving rise to the violent muscular spasms from which 

 the patient suffers in consequence of the powerful poison which 

 the tetanus bacillus forms at the point of infection. In diph- 



*For a full consideration of this subject see Vaughan and Novy. The Cellu- 

 lar Toxins. igo2. 



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