144 IMMUNE SERA 



haemorrhages are more frequent in the stomach, 

 caecum, lungs, and heart than elsewhere. 



It was natural to think that a formation of preci- 

 pitins was in some way responsible for the symptoms 

 of serum sickness or for the rare cases of sudden 

 death following injections of antitoxin sera. It was 

 conclusively shown, however, by v, Pirquet and 

 Schick, Rosenau and Anderson, as well as others, 

 that this is not the case. It was found, for instance 

 that the symptoms of serum sickness appear within 

 eight to thirteen days following the first injection of 

 horse serum, whereas it requires about three weeks 

 for precipitins to appear in the blood in children 

 after the injection of horse serum. Furthermore, 

 the formation of precipitins does not take place as 

 readily in man following the injection of horse serum 

 as it does in rabbits. In fact, v. Pirquet and 

 Schick found that sometimes even after the injec- 

 tion of 200 c.c. there was no production of precip- 

 itins. Finally Rostoski has called attention to the 

 fact that the precipitin action is a test-tube pheno- 

 menon only, and does not occur in vivo. It is well 

 to bear these facts in mind. In a recent discussion 

 on the treatment of severe cases of diphtheria in 

 which the intravenous administration of large doses 

 of antitoxin was recommended, one of the speakers 

 alluded to the dangers from precipitin formation as 

 contra indicating such a procedure. Such fears are 

 groundless. 



