SERUM THERAPY OF DIPHTHERIA. 



77 



for the aim in the treatment is to neutralize as soon as possible all the free 

 and partly bound toxin. 



According to the researches of Doenitz, more recently confirmed and 

 extended by Fritz Meyer, it was established that large amounts of antitoxin 

 can even neutralize toxin already attached to the tissue cells. Men with 

 practical experience like Heubner, give 4000 units as the initial dose. In 

 the United States doses as high as 10,000 to 100,000 I. E. have been admin- 

 istered with good results. The view of large dosage is being gradually taken 

 up also in Germany. At any rate it is by far better to give too much than too 

 little. If the first injection does not suffice it should be repeated the next day. 

 The only possible drawback associated with the use of excessive amounts is 

 the possibility of serum sickness, to be mentioned later. Netter has found 

 that the administration of i gm. of calcium chloride on three successive days 

 prevents serum sickness. 



The serum has thus far been as a rule injected subcutaneously. This 

 method is very practical and as far as anaphylaxis is concerned, is the least 

 dangerous. The disadvantage, however, is that it is very slowly absorbed. 

 Madsen and Hendersen-Smith have shown that but a trace of antitoxin can 

 be found in the blood of the patient four and three-fourth hours after the 

 injection, and only after two to three days can larger amounts be demon- 

 strated. In view of this, Morgenroth recommends the gluteal intramuscular 

 injection for here a much more rapid absorption follows. In cases of danger- 

 ous illness intravenous injection may be undertaken. For this purpose 

 Meyer advises a serum free of carbolic acid, although this is not absolutely 

 necessary. 



The importance of the method of injection is clearly shown by the comparative 

 experiments of Berghaus. In order to save a guinea-pig injected with a definite amount 

 of toxin and followed in i hour by antitoxin, it was necessary to employ: 

 0.08 I. E. by intracardial injection. 

 7.0 I.E. by intraperitoneal injection. 

 40.00 I. E. by subcutaneous injection. 



Thus the curative power was increased 500 fold by placing the antitoxin directly into the 

 circulation. 



The treatment of diphtheria must by no means be limited to serum 

 therapy. A symptom of grave prognosis is the lowered blood pressure 

 which must be counteracted by infusions of 1/2 liter of physiological salt 

 solution containing five to six drops of adrenalin. 



The question whether the use of concentrated antitoxin is therapeutically 

 more efficient than the non-concentrated is still a matter for discussion. 

 Numerous authors claim that sera of medium strengths (about 400 I. E.) 

 are most efficient. The highly concentrated sera are much more expensive. 



For prophylactic purposes 500 to 1,000 units injected subcutaneously 

 usually suffice. Protection thus attained lasts about three weeks. 



