IDIOSYNCRASIES AND ANAPHYLAXIS 



173 



now been made, and a great deal remains to be done; but I believe 

 that there is scarcely any field of study which, from the standpoint 

 of the clinician, promises such fruitful returns as the investigation 

 of our common infectious diseases and their pathogenic agents along 

 these lines. 



At the present state of our knowledge it is, of course, very diffi- 

 cult to decide which symptoms in a given disease are due to bacterial 

 toxins, which to endotoxins, which to ptomains, and which to ana- 

 phylatoxins; but it is important to recognize that with the discovery 

 of the latter a new vista has been opened up, along which we can see 

 the possible manner in which some of those organisms may produce 



FIG. 10 

 ,15 



Autoreinfection 



Threshold of 

 Clinical 



'nifestations 



Scarlatina 



Sequela 



Diagram illustrating the interaction between antigens and antibodies in their relation to the clinical 

 picture and a sequela of scarlatina. (Taken from v. Pirquet.) 



symptoms of disease and even death, which are recognizedly not 

 toxin producers, and whose endotoxins also are not sufficiently active 

 to cause the clinically recognizable results of infection. This is 

 indeed a most attractive field for speculation, but as a further dis- 

 cussion of the many possibilities and problems which suggest them- 

 selves in this connection would of necessity be purely theoretical 

 in character, it would be better to leave this for some future occasion, 

 when actual experimental data may be at our disposal. u 



Idiosyncrasies and Anaphylaxis. I have pointed out above that the 

 development of a definite symptom-complex following the parenteral 

 introduction of horse serum (i. e., of alien albumin) suggests the 



