568 ANAPHYLAXTS 



searches would tend to indicate that the two subjects are indeed closely 

 related. An enormous amount of work has already been done on ana- 

 phylaxis, the subject being of the greatest importance, not only on ac- 

 count of its practical bearing on serum therapy, but because of its inti- 

 mate relationship to the subjects of infection and immunity, and the 

 new light that these studies may throw upon the nature and mechanism 

 of these processes. Although the phenomena of anaphylaxis are now 

 known to be due to the proteins, and while the symptoms and lesions 

 of the condition are fairly well understood, the exact nature and mecha- 

 nism involved in the process are not established, and the entire subject 

 is fraught with so much interest as regards infection and immunity that 

 it affords a fruitful field for further research. 



In this chapter will be presented the known facts regarding anaphy- 

 laxis and the theories that have been advanced in explanation of its 

 nature and mechanism, the consideration of anaphylaxis in its practical 

 application to medicine being left for the following chapter. 



Historic. The first observation of anaphylaxis as it occurs in an 

 infectious disease was probably made by Jenner in 1798. This investi- 

 gator observed the sudden appearance of an "efflorescence of a palish 

 red color" about the parts where variolous matter had been injected into 

 a woman who had had cowpox thirty-one years before. 



In 1839 Magendi found that rabbits that had been injected with egg- 

 albumin died after a repetition of the injection, a phenomenon strikingly 

 similar to that observed sixty-five years later by Theobald Smith 

 following injections of horse serum. This phenomenon was subsequently 

 studied thoroughly by Rosenau and Anderson and Otto. 



While the effects of diphtheria and tetanus antitoxins were being 

 studied, peculiar and apparently paradoxic results were occasionally 

 observed during immunization of animals with the bacterial toxins. 

 Thus in 1895 Brieger l reported the case of a goat that was highly im- 

 munized against tetanus and yet was subject to tetanus. In 1901 von 

 Behring and Kitashima 2 reported similar findings with diphtheria in 

 horse immunized against that infection. At this time it was shown that 

 the results could not be due to the cumulative effect of the toxin, and 

 the explanation offered aimed to show that the process was purely his- 

 togenetic, and based upon the assumption that receptors attached to the 

 body-cells had a closer affinity for toxin than the free (antitoxin) re- 

 ceptors in the blood-stream. At the present time toxin hypersuscep- 

 tibility is held by some to be a true anaphylactic reaction brought about 

 1 Zeitschr. f. Hyg., 1895, 101. 2 Berl. klin. Wochenschr., 1901, xxxviii, 157. 



