6o4 Typhoid Fever 



In case the culture is not pure, the typhoid bacillus can be sepa- 

 rated from contaminating organisms by plating. 



The Isolation of the Bacillus from the Feces. — This method of 

 making the diagnosis has practically been abandoned because of its 

 uncertainty, its cumbersomeness, its tediousness, and because the 

 preceding methods suffice in all cases. 



An excellent resume of the many methods employed for isolating 

 the bacillus from the stools has been published by Peabody and 

 Pratt,* and is appropriate reading for those interested in this 

 subject. 



The Conjunctival Reaction. — An additional aid to the diagnosis of 

 typhoid in doubtful cases based upon the WolfE-Eisner-Calmette 

 reaction in tuberculosis is the "ocular typhoid reaction" of Chan- 

 temesse.f This test consists in the instillation into the eye of a 

 solution made by extracting the tj^hoid bacillus as follows: " Gela- 

 tin plates covered with an eighteen- to twenty-hour-old culture of 

 virulent typhoid bacilli were washed with 4 to 5 cc. of sterile water. 

 The suspension thus obtained was heated to 6o°C., centrifugated, 

 and the supernatant fluid withdrawn. The centrifugated organisms 

 were then dried and triturated. A second suspension of these 

 broken up bacillary bodies was then made, and allowed to stand for 

 from two to three days at 6o°C. The extract thus obtained, after 

 removing the disintegrated and digested remnants, was precipitated 

 with alcohol, forming a fine coagulum. This was subsequently 

 dried, powdered and dissolved in sterile water in the proportion 

 of 0.02 mg. to a drop."t 



When one drop of this is placed upon the conjunctiva of a patient 

 in the early days of typhoid fever, diffuse redness increases and 

 becomes marked in two or three hours. There is also some feeling of 

 heat in the eye. Tears flow freely, and there is a slight mucopuru- 

 lent exudate in some cases. The reaction persists about ten hours 

 and then declines, usually disappearing in twenty-four hours. Ham- 

 burger§ confirmed the results of Chantemesse. It is too early to say 

 how useful the reaction is, but it seems to promise aid in diagnosing 

 difficult cases. 



Differential Diagnosis of the Typhoid and Colon Bacilli. — This 

 constitutes the chief perplexity of bacteriologic work with the typhoid 

 bacillus, and is the great bugbear of beginners. A great deal of 

 energy has been expended upon it, a considerable literature has been 

 written about it, and much still remains to be learned by which it may 

 be simplified. 



Two chief methods are in vogue at present: 



1. The serum differentiation. 



2. The culture differentiation. 



* "Boston Medical and Surgical Journal," 1907. 



t "Deutsche med. Wochenschrift," 1907, No. 31, p. 1264. 



% See Hamburger, "Jour. Amer. Med. Assoc," l, 17, p. 1344, April 25, 1908. 



§ Log. cit. 



