178 INFECTIONS OF THE DIGESTIVE TRACT 



Dr. Flexner 1 and his associates. Of these facts the most 

 important have to do with the pathological alterations 

 observed in the intestinal mucous membrane in the 

 course of human dysentery and in the course of experi- 

 mental intoxications. By intravenously injecting into 

 rabbits the poison obtained by permitting the bacilli 

 to undergo a process of autolysis or self-digestion, Dr. 

 Flexner was able to reproduce intestinal lesions analogous 

 to those observed in human dysentery ; namely, inflam- 

 matory, sometimes diphtheritic processes, especially in 

 the large intestine and often attended by hsemorrhagic 

 changes. It is quite clear that these lesions are inciden- 

 tal to an elimination of the injected poison into the in- 

 testine and that the damage done to the intestinal 

 structures is due primarily to the contact with the 

 poison in the blood during the act of elimination or 

 secretion. It seems probable that a secondary invasion 

 of the damaged structure by intestinal bacteria forms 

 an essential part of the dysenteric process. These pri- 

 mary eliminative lesions are, as pointed out by Flexner, 

 analogous to those experimentally called forth by 

 corrosive sublimate and by ricin. I observed, many 

 years ago, hsemorrhagic and necrotic intestinal lesions in 

 dogs after intravenous infusions of urea, and these in- 

 juries also belong to the group of eliminative manifes- 

 tations. The special value of Flexner's studies lies, it 

 appears to me, in the fact that they show for the first 



1 "The Pathogenesis of Experimental Colitis, and the Relation 

 of Colitis in Animals and Man," Journ. of Exper. Med., viii, p. 514, 

 1906. 



