502 PATHOGENIC BACTERIA. 



these were examined, and the one case in which I en- 

 countered it was typical typhoid. 



XII. The Clinical Value of the Serum Diagnosis. — 

 Granting the precision of method of serum diagnosis, it 

 is doubtless of great diagnostic importance. As shown 

 by the statistics given, the reaction failed to develop in 

 only 4.5 per cent, out of a total of 2393 cases of typhoid 

 fever. Again, it is highly probable that this small per- 

 centage of failures would be farther reduced if the test 

 (when negative at the first examination) were repeated 

 every day or two until convalescence is fully established. 



Rumpf 1 and Kraus and Buswell 2 report a number of 

 cases of typhoid which were favorably influenced by the 

 hypodermic injection of small quantities of sterilized cult- 

 ures of Bacillus pyocyaneus. 



Following the lines of experimentation suggested by 

 Haffkine's researches upon preventive vaccination against 

 cholera Asiatica, Pfeiffer and Kolle, and Wright and Sem- 

 ple have used the subcutaneous injection of sterilized cult- 

 ures as a prophylactic measure. One cubic centimeter of 

 a bouillon culture sterilized by heat is thought to be suffi- 

 cient Wright and Semple 3 report 18 cases in which it was 

 used, and by experiment showed the blood to be changed 

 similarly to that of typhoid patients and convalescents. 

 This change consisted in the destruction of motility and 

 agglutination of the bacilli, as seen in Widal's reaction. 



Walger 4 reports four cases treated successfully with a 

 serum obtained from convalescent patients. Ten c.cm. 

 were given at a dose, and the injection was repeated in 

 one case with relapse. 



Jez 5 believes that the antitoxic principle in typhoid 

 fever is contained in some of the internal organs instead 

 of the blood, and claims to have obtained remarkable 

 results in eighteen cases treated with extracts of the bone- 



1 Deutsche med. Wochenschrift, 1893, No. 41. 



2 Wien. klin. Wochenschrift, July 12, 1894. 



3 Brit. Med. Jour., 1897,' i., p. 256. 



4 Munch, med. Wochenschrift, Sept. 27, 1898. 

 ^ 5 Med. moderne, Mar. 25, 1899. 



