DIPHTHERIA. 369 



taken up by the nerve endings and reaches the 

 ganglionic cells by way of the axis cylinders, 

 whereas the antitoxin which is injected remains 

 chiefly in the blood and lymphatic circulations. 

 Hence,, the toxin, to a certain extent, is isolated 

 and less accessible to the action of the antitoxin. 



Concerning diphtheria, the affinity between Diphtheria. 

 toxin and antitoxin is relatively strong, for com- 

 plete neutralization in the test-glass takes place in 

 about fifteen minutes (Ehrlich). On the other 

 hand, clinical experience indicates that the affinity 

 of diphtheria toxin for tissue cells is less than that 

 of tetanus toxin, for diphtheria may readily be 

 cured on the second or third day of the disease, 

 whereas a cure of tetanus is rarely affected. These 

 would seem to be favorable conditions for success- 

 ful serum therapy. Although the toxin of diph- 

 theria may attack the nervous system, the paraly- 

 sis seen in such cases is seldom fatal. On the basis 

 of anatomic findings in fatal cases it seems prob- 

 able that the greater portion of the toxin is taken 

 up by parenchymatous and lymphatic organs, and 

 by connective tissues (animal experiments), which 

 compared with the nervous tissue are of less imme- 

 diate importance for life and have greater recuper- 

 ative powers. We may infer from clinical experi- 

 ence that diphtheria toxin is so situated in the 

 body that it is accessible to the action of the anti- 

 toxin. 



We have, therefore, the following factors important 

 which apparently are of importance for the sue- f?" success. 

 cess of antitoxic therapy: 1. The concentration 

 (strength) of the antitoxin which is injected. 2. 

 Its freedom from contamination and adventitious 

 toxins. 3. The time of its administration. 4. The 



