634 Typhoid Fever 



of which the chief is probably ammonia. It forms no coagulating 

 or proteolytic enzymes. 



Toxic Products. — The disproportion of local to constitutional dis- 

 turbance in typhoid fever and the irritative and necrotic charac- 

 ter of its lesions suggest that we have to do with a toxic organism. 

 Brieger and Frankel have, indeed, separated a toxalbumin, which 

 they thought to be the specific poison, from bouillon cultures. When 

 injected into guinea-pigs the typhotoxin of Brieger causes salivation, 

 accelerated respiration, diarrhea, mydriasis, and death in from 

 twenty-four to forty-eight, hours. Klemperer and Levy also point 

 out, as affording clinical proof of the presence of toxin, the occasional 

 fatal cases in which the tj^ical picture of typhoid has been without 

 the characteristic postmortem lesions, the diagnosis being made by 

 the discovery of the bacilli in the spleen. 



Pfeiffer and Kolle* found toxic substance in the bodies of the 

 bacilli only. It was not, like the toxins of diphtheria and tetanus, 

 dissolved in the culture-medium. This was an obstacle to the immu- 

 nization experiments of both Pfeiffer and Kolle and Loffler and Abel,t 

 for the only method of immunizing animals was to make massive 

 agar-agar cultures, scrape the bacilli from the surface, and distribute 

 them through an indifferent fluid before injecting them into animals. 



If the bacilli grown upon ordinary culture-media are several times 

 washed in distilled water, and then allowed to macerate in norrnal 

 salt solution, autolysis takes place and a toxin is liberated, showing 

 that the toxin is intracellular. Macfadyen and RowlandJ liberated 

 an intracellular toxin from cultures of the typhoid bacilli by freezing 

 them with liquid air and grinding them in an agate mortar. Animals 

 immunized with this poison produced an antiserum active against it, 

 but useless against infection with typhoid baciUi. Wright, of Net- 

 ley,! observes that Macfadyen's method of securing this intracel- 

 lular toxin was unnecessarily cumbersome, as the body juices of 

 animals injected with dead cultures of the bacilli dissolve them at 

 once and thus liberate the same toxic product. 



Besredkall and Macfayden think** that exotoxin is also formed. 

 Vaughanft has obtained poisonous and non-poisonous fractions by 

 extracting massive cultures of typhoid bacilli with 2 per cent, solu- 

 tions of sodium hydrate in absolute alcohol at 78°C. 



Mode of Infection. — The tj^jhoid bacillus enters the body by 

 way of the alimentary tract with infected foods and water. It is 

 commonly beheved that the great majority of typhoid epidemics, 

 and the sporadic cases as well are caused by infected drinking water. 



* "Deutsche med. Wochenschrift," Nov. 12, 1896. 



t "Centralbl. f. Bakt. u. Parasitenk.," Jan. 23, 1896, Bd. xix, No. 23, p. 51. 



t"Brit. Med. Jour.," 1963. 



§ Ibid., April 4, 1903, i, p. 786. 



II "Ann. de I'lnst. Pasteur," 1895, x, 1896, xi. 

 ** "Centralbl. f. Bakt.," etc., 1906, i. 

 tt "Amer. Jour. Med. Sci.," 1908, cxxxvi. 



