598 GASTRO-INTESTINAL BACTERIOLOGY 



Bacillus coli or Bacillus acidophilus, produced under like conditions. 

 In other words, available evidence points strongly to the view that 

 cholera vibrios, typhoid, dysentery and paratyphoid bacilli and similar 

 organisms produce their characteristic and harmful effects when they 

 are developing in media free from utilizable carbohydrate; when 

 utilizable carbohydrates are added to these media, non-characteristic, 

 harmless products are formed. It is frankly admitted that the chemis- 

 try of the products of nitrogenous metabolism of pathogenic bacteria 

 is wholly unknown, and a rigorous proof of a relation between nitro- 

 genous metabolism and disease is yet to be elucidated; the significant 

 fact that the products of fermentation of these organisms are almost 

 certainly innocuous to the host cannot be disregarded. 



In the absence of any definite indication to the contrary it would be 

 logical to attempt to maintain a sufficient concentration of carbo- 

 hydrate within the intestinal canal in these infections as a therapeutic 

 measure. This would be advantageous to the patient as a physio- 

 logical procedure, as Coleman and Shaffer 1 have shown in their clas- 

 sical studies in typhoid, and it would provide continuously at least 

 a minimal amount of readily utilizable carbohydrate which would 

 shift the metabolism of all the intestinal organisms, pathogenic and 

 non-pathogenic, in such a manner that harmless lactic acid would be 

 formed by them. The bacteria under these conditions would theoreti- 

 cally, and in all probability practically, derive their energy from the 

 readily fermentable carbohydrate and thus not only minimize their 

 action upon the proteins of the intestinal contents, 2 but would tend to 

 create an acid reaction there which in itself would be a potent agent in 

 restricting the activity of the pathogenic organisms in the alimentary 

 tract. 



The associated bacteria of the intestinal tract also form acids under 

 these conditions; Bacillus coli does not form indol, and other products 

 of putrefaction are absent. Within a few days, under favorable cir- 

 cumstances, the cumulative effect of a diet liberal in carbohydrate 

 will lead to a considerable development of aciduric bacteria, especially 



1 Arch. Int. Med., 1909, iv, 538. 



2 It is a well-attested fact that typhoid bacilli develop within the tissues of the body, 

 and it might appear that a carbohydrate diet would therefore be ineffective; it is import- 

 ant to remember that the blood normally contains about 0.08 per cent, dextrose, an 

 amount amply sufficient to protect protein from their attack. A liberal carbohydrate 

 diet should tend to maintain the concentration of blood sugar at its physiological level. 

 Recently Simonds (Jour. Inf. Dis., 1915) has shown that the products arising from the 

 autolysis of typhoid bacilli grown in dextrose media are decidedly less toxic for rabbits 

 than those grown in dextrose-free media when acted upon by specific lytic sera. This 

 observation may well have an important bearing upon the case in question. 



