340 A MANUAL OF BACTERIOLOGY 



The antitoxic constituent of diphtheria antitoxin is 

 globulin in nature, or is intimately associated with the 

 globulin content of the serum. Thus Atkinson found that 

 if the serum is precipitated by saturation with magnesium 

 sulphate, the whole of the antitoxin is carried down with 

 the precipitate, and also that the globulin content of the 

 blood-serum of antitoxin horses is increased. His results 

 were confirmed by Ledingham. 1 



Since the introduction of antitoxin treatment, which was com- 

 menced about the middle of 1894, there has been a steady decline 

 in the case mortality from diphtheria, especially in London, 

 where probably the majority of the cases are injected with anti- 

 toxin. From 1891 to 1894 the case mortality from diphtheria in 

 the hospitals of the Metropolitan Asylums Board averaged about 

 30 per cent., in 1895 it was 22-8 per cent., and afterwards steadily 

 fell, until during the last five years it has ranged between 6-2 and 

 7*9 per cent. 



If there is a reasonable probability that the case is one of diph- 

 theria, antitoxin should be immediately given, and treatment 

 should not be delayed for the result of the bacteriological exami- 

 nation. The statistics show that in cases treated on the first day 

 of the disease the case mortality is 3-3, on the second day it is 6-5 

 on the third day 10-6, on the fourth day 12-9, and on the fifth day 

 and afterwards 14- 8 per cent. 



In mild cases, doses of 6,000-12,000 units should be given. In 

 cases of medium severity doses of 12,000-20,000 units, and in bad 

 cases 24,000-30,000 units should be given. The larger doses 

 should be given to cases treated at a late stage. In bad cases, to 

 bring the patient under the influence of the antitoxin as rapidly 

 as possible the first dose may be administered intravenously. The 

 dose may have to be repeated once or twice in mild cases, in bad 

 cases perhaps every six or twelve hours until several doses have 

 been given, the guide being the general condition of the patient 

 and the rapidity of the separation of the membrane. In addition 

 to antitoxin, the recumbent posture and general and local treat- 

 ment should be pursued as usual. 



1 Journ. of Hygiene, vol. vii, 1907, p. 65. See also Homer, ibid. vol. xv, 

 1916, p. 388. 



