SERUM DISEASE 571 



conditions commonly ascribed to idiosyncrasies toward certain sub- 

 stances, such as horse asthma, satinwood dermatitis, buckwheat poison- 

 ing, urticarias due to the ingestion of strawberries, pork, and the like, 

 the relation of anaphylaxis to the processes involved is more intimate. 

 Here, indeed, we may regard the symptoms as entirely anaphylactic in 

 origin and character, as the substances in themselves, such as serum, 

 egg-albumen, horse effluvia, etc., are not regarded as toxic and we have 

 not the coincident effects of toxins, endotoxins, and ptomains, as in 

 bacterial infections. 



Here, indeed, we may accept Vaughan's and Friedberger's theory 

 as to the action of the protein poison in its entirety, regarding it the same 

 in all proteins, and set free from the protein molecule by the so-called 

 "ferment," which is in the nature of a protein sensitizer or amboceptor, 

 and which, with a complement, brings about lysis or cleavage of the 

 molecule, just as a similar ferment or antibody, called bacteriolysin, 

 disrupts a bacterial cell or its protein constituents. In short, we may 

 say that the work of Vaughan and his collaborators has shown us the 

 presence of this poison in all protein material with a method of extracting 

 it in vitro. Friedberger and his collaborators have shown how this 

 poison is set free in the body through the agency of the " ferment." 

 von Pirquet has studied the question at the bedside, dispensing with the 

 microscope and test-tube and depending solely upon the vital processes 

 and reaction, skilfully combining laboratory findings with bedside ob- 

 servations in fact, he built up his theory on the nature of infection and 

 immunity before the role of the protein poison was discovered, and 

 subsequent work has added support to his conceptions. Of clinical and 

 practical importance in this connection are serum disease and hyper- 

 sensitiveness or idiosyncrasies for other proteins and certain drugs. 



SERUM DISEASE 



This name was applied by von Pirquet and Schick 1 to the various 

 clinical manifestations, such as eruptions, fever, edema, and pain in the 

 joints, following the injection of horse serum. These symptoms are due 

 to the horse serum itself, for, as was early shown by Johannessen, 2 

 Bokay, 3 and others, they may manifest themselves after the injection of 

 sterile normal horse serum. The serum, moreover, of certain horses 



x "Die Serumkrankheit," Leipsic, Deuticke, 1905. 



2 Deutsch. med. Wochenschr., 1895, 21, 855 



3 Jahresb. f Kindesh., 1897, xliv, 133. 



