THE GROUP OF THE DYSENTERY BACILLI 323 



Specific bacteriolysins have been demonstrated in immune sera 

 in vitro by Shiga 1 and in vivo by Kruse. 2 Specific precipitins, which 

 in dilutions of 1 to 10 or greater will produce a precipitate in broth 

 filtrates of the homologous strain, but not, as a rule, for other types 

 of the dysentery bacilli are also found. The sera of patients who 

 have recovered from attacks of bacillary dysentery usually contain 

 specific agglutinins which are active even in dilutions of 1 to 50. 

 Specific precipitins, lysins, and opsonins are also demonstrable in the 

 sera of these patients. 



Therapy. Attempts to immunize man with vaccines, both mono- 

 and polyvalent, 3 sensitized vaccines (bacteria which have been in 

 contact with antidysentery serum, then centrifugalized, washed, and 

 suspended in salt solution, according to the method of Besredka and 

 of Gay), and the use of antisera, usually derived from immunized 

 horses, have not been generally successful, although a few favorable 

 results have been recorded. 



Bacteriological Diagnosis. (a) Agglutinin Reaction. The sera of 

 normal individuals rarely agglutinate dysentery bacilli in dilutions 

 greater than 1 to 10, although Dopter 4 states that the Flexner organ- 

 ism may be clumped with the serum of apparently normal individuals 

 in a dilution greater than 1 to 10. For this reason agglutination tests 

 should be made in a dilution of 1 to 20 to 1 to 30 with the Shiga 

 organism, and 1 to 80 to 1 to 100 with the Flexner strain in each 

 case examined, since one or the other organism, or both, may be 

 present in typical cases of bacillary dysentery. Agglutinins do not 

 as a rule appear in mild cases, and in severe cases they are not 

 demonstrable until from the seventh to the tenth day on the average. 



The serum of dysentery carriers, both those giving a history of a 

 previous attack and those with the negative dysentery history, fre- 

 quently agglutinates either with Shiga or Flexner bacilli. The agglu- 

 tination reaction, therefore, is not conclusive for clinical diagnosis 

 unless a negative reaction is obtained early in the disease followed 

 by a positive reaction on or after the seventh to the tenth day. 



(6) Isolation of Dysentery Bacilli from the Feces. Dysentery bacilli 

 do not invade the blood stream as a rule, and they are not found 

 in the urine. The bacteriological diagnosis, therefore, depends upon 



1 Loc. cit. 



2 Deutsch. med. Wchnschr., 1902. 



3 Shiga, Deutsch. med. Wchnschr., 1901, Nos. 43 and 45; Kruse, ibid., 1903, Nos. 1 

 and 3. 



4 Loc, cit., p. 91. 



