791 



of the ordinary foodstuffs have no significant peristalsis stimulating effect 

 in the intestine unless decomposed by bacterial action. We know from ex- 

 perience that diarrhea is much more common in infants fed on milk 

 known to be contaminated and which has not been pasteurized or boiled. 

 It is not unusual to observe the occurrence of vomiting and diarrhea in 

 a whole group of infants fed on infected milk from a common source. 



Although there is a great deal of circumstantial evidence that bac- 

 terial decomposition of food in the intestinal tract is a cause of infantile 

 diarrhea, there is not a great deal of exact scientific proof. Studies of the 

 bacterial flora of the stools of infants suffering from diarrhea have failed 

 to throw a great deal of light on the subject. With the exception of bacil- 

 lary dysentery, a recognized specific infectious disease, the types of micro- 

 organisms found in the stools of infants suffering from severe or evdn 

 fatal diarrhea are usually not essentially different from those of the normal 

 breast fed infant. Examinations of the bacterial flora of the upper in- 

 testine have given more definite information. Moro and Tissier have 

 shown, on autopsy material, that the upper intestinal tract of infants suf- 

 fering from severe diarrhea usually contains many organisms largely of 

 the coli group, whereas the intestinal tracts of infants dying from causes 

 other than diarrhea are relatively bacteria free. Bessau and Bossert 

 have studied the bacterial flora of living infants by means of a specially 

 constructed duodenal catheter and have demonstrated that normally the 

 duodenum contains only a few cocci, yeasts and some gram negative bacilli 

 (easily distinguishable from B. coli). In infants suffering from diarrhea, 

 they found invariably an invasion of the duodenum with such organisms 

 as B. coli and B. lactis aorogenes, organisms ordinarily present only in the 

 lower intestine. 'Bahrdt, Edelstein, Hanssen and Welde found that when 

 milk infected with certain strains of B. coli was fed to dogs in sufficient 

 amounts to cause the passage of unkilled organisms into the duodenum a 

 severe diarrhea resulted. Koessler and Hanke(a) have shown that a 

 strain of B. coli isolated from the stools may when grown in the presence of 

 an excess of sugar quantitatively convert the amino acid histidin, a product 

 of the digestion of protein, into histamin (beta-imidazolethylamin), a 

 substance which Mellanby has found capable of causing vomiting and 

 severe diarrhea when administered by mouth. This affords an explana- 

 tion of how an organism such as the B. coli, which is relatively harmless 

 in the large intestine, where its substrat is not such as to allow of the 

 production of toxic substances, may become harmful when transplanted 

 to a portion of the intestine where conditions are favorable for the forma- 

 tion of substances capable of doing harm. 



An excess of fat in the food leads to a slower emptying of the stomach 

 and an excess of sugar affords a favorable culture medium for such bac- 

 teria as may be present in the stomach or intestines. An excess of even a 



