CHAPTER XXXI. 

 ANAPHYLAXIS. 



Dallera, in 1874, and a number of physiologists of that 

 period, observed peculiar skin eruptions following the trans- 

 fusion of blood, that is, the introduction of foreign proteins. 

 In the years subsequent to the introduction of diphtheria 

 antitoxin (1890) characteristic "serum rashes" were not 

 infrequently reported, sometimes accompanied by more or 

 less severe general symptoms and occasionally death; — a 

 train of phenomena to which the name "serum sickness" 

 was later applied, since it was shown that it was the horse 

 serum (foreign protein) that was the cause, and not the anti- 

 toxin itself. In 1898 Richet and Hericourt noticed that some 

 of the dogs which they were attempting to immunize against 

 toxic eel serum not only were not immunized but suffered 

 even more severely after the second injection. They 

 obtained similar results with an extract of mussels which 

 contain a toxin. Richet gave the name "anaphylaxis" 

 ("no protection") to this phenomenon to distinguish it from 

 immunity or prophylaxis (protection). 



All the above-mentioned observations led to no special 

 investigations as to their cause. In 1903 Arthus noticed 

 abscess formation, necrosis and sloughing following several 

 injections of horse serum in immediately adjacent parts of the 

 skin in rabbits ("Arthus' phenomenon"). Theobald Smith, 

 in 1904, observed the death of guinea-pigs following properly 

 spaced injections of horse serum. This subject was investigated 

 by Otto and by Rosenau and Anderson in this country and 

 about the same time von Pirquet and Schick were making a 

 study of serum rashes mentioned above. The publications of 

 these men led to a widespread study of the subject of injec- 

 tions of foreign proteins. It is now a well-established fact that 



