DYSENTERY AND ALLIED BACILLI 



MAX LEVI N E 



From the Laboratory of the Central Medical Department, A. E. F., Dijon, France, and the 

 Army Medical School, Washington, D. C. 



In France we not infrequently experienced difficulties in growing 

 dysentery bacilli and work was therefore begun ( 1 ) to differentiate the 

 true dysentery bacilli, which are universally recognized as pathogenic, 

 from the atypical or dysentery-like organisms (B. ambiguus, B. alka- 

 lescens, and B. dispar) many strains of which are nonpathogenic and 

 whose etiologic significance is questionable; (2) to devise a more 

 dependable, and if possible more simple medium, than the nutrient agar 

 (phenolphthalein titration) for the isolation of dysentery bacilli. 



The nomenclature in the group of dysentery bacilli has become 

 quite confused. In this paper the following will be adhered to: 

 B. dys. Shiga corresponds to the original Shiga-Kruse mannite negative 

 type. The term B. flexneri includes both the B. dys. Flexner and 

 Y types, and when possible it will be qualified with the race of the 

 strain, such as V, W, X, Y or Z. The terms B. dys. Flexner and 

 B. dys. Y are used in their old significance. 



Serologic tests and studies on classification were beyond the scope of the 

 investigation. Agglutination with stock Flexner and Y serums were carried 

 out with 59 cultures. Acid production in a number of sugars and other fer- 

 mentable substances, as well as the reactions in milk and the indol test, were 

 observed on all the stains. 



A total of 111 cultures were considered in this study. These were dis- 

 tributed as follows: B. dys. Shiga, 17; B. ambiguus, 5; B. flexneri, 60; B. alka- 

 lescens, 12; B. dispar, 11; miscellaneous, 6. 



The Shiga cultures, with one exception, were stock strains found at the 

 Central Medical Laboratory or the Army Medical School; several were 

 duplicates. 



The ambiguus strains included 3 (67, 68 and 69) from Dr. Andrews, St. 

 Bartholomew's Hospital, London. One (4) was found at the Central Medical 

 Laboratory marked B. dys. Shiga Fletcher vaccine stain, and another (101) 

 obtained from the Army Medical School and probably a duplicate of (4), was 

 marked B. dys. Shiga Fletcher 1. Serologic tests were not made with (101). 

 The other (4) failed to agglutinate with several Shiga serums, and as both were 

 positive for indol they are here considered as B. ambiguus. 



The 60 cultures of B. flexneri include strains isolated during the war and 

 also standard stock cultures. Included in this group are the old Flexner and 

 Y types and authentic strains of the English groups V, W, X, Y, Z, VZ and WX, 

 which were sent me by .Dr. Andrews. 



Received for publication Feb. 16, 1920. 



