TRANSFUSION OF BLOOD 841 



may occur. Herpetiform vesicles may develop about the mouth. The 

 symptoms are rarely alarming and usually the reaction consists of only a 

 simple rise in temperature. ' 



These reactions follow the giving of hlood by any method. They are 

 apparently much more common when blood is altered by an anticoagulant 

 than when blood is given without addition of such a substance. The fre- 

 quency of such reactions varies greatly according to different observers. 

 It seems that in round numbers outspoken definite reactions occur fol- 

 lowing transfusion of blood, as such, in about 15 per cent of the instances 

 and with citrated blood in about 35 per cent of the instances. 



Reactions of this type are generally considered as dependent upon some 

 not clearly demonstrated alterations of blood, associated with its removal 

 from the body. In some cases, alteration of the patient's blood seems to 

 play a part. This is thought to be the case because these reactions appear 

 to be commoner in patients with extensive pathology of their hematopoietic 

 organs, such as occurs in pernicious anemia, than in those whose hemato- 

 poietic system is of a normal type, such as is found in cases with anemia 

 due to acute blood loss. 



Satterlee and Hooker, in a review of the known facts concerning such 

 reactions, suggest three possible mechanisms by which they may be pro- 

 duced. One is that the trypsin-antitrypsin balance in the circulating 

 blood of the recipient is so disturbed as to result in the immediate forma- 

 tion of serotoxin from cleavage products. A second theory is that the 

 action of the protective colloids in the body cells of the recipient may be 

 upset so that these cells are exposed to a reaction of the antigen and 

 antibody present in the circulation of the recipient, but harmless to the 

 protected cells. The third theory, one which is substantiated by many 

 facts, concerns the possibility of a toxic disturbance in the circulation of 

 the recipient by the introduction of blood which, though perfectly fluid, 

 may be undergoing incipient coagulation changes due to the physical 

 influences to which it is subjected in the process of transfer. The experi- 

 mental work of Drinker and Brittingham and Wright and Minot, as well 

 as the clinical results of workers experienced in the technic of trans- 

 fusion, suggests that the coagulation changes may account for most of 

 these reactions. 



Novy and DeKruif attribute the toxicity of blood in the precoagula- 

 tion stage to the presence of poison, anaphylatoxin, which is also present 

 in greater or less concentration in normal serum. The mechanism of the 

 production of this substance is the subject of an interesting theory pro- 

 posed by these authors, and it may explain certain post-transfusion reac- 

 tions. Novy and DeKruif believe that the matrix of the poison is always 

 prc.-cnt in the circulating blood and is a substance as labile as fibrinogen, 

 and that just as fibrinogen is changed by thrombin to fibrin, so the matrix 

 is converted through the action of a great variety of substances into 



