SALVARSAN IN THE TREATMENT OF SYPHILIS 257 



after the use of salvarasn, and which he refers to the liberation of 

 toxins from the killed spirochetes and to their local irritating effect. 

 He points out that if such a reaction should affect one of the cranial 

 nerves at a point where this passes through a narrow, bony canal, 

 disturbance in function would be a very probable consequence, owing 

 to swelling and resultant compression. Such disturbances, however, 

 do not occur within a few hours of the injection, as in the case of 

 the true Herxheimer reaction, affecting the skin, but only after 

 twenty-four hours, or even after three or four days, as the vascular 

 supply of the nerves is but little developed and a longer time must 

 elapse before a sufficient number of spirochetes has been killed, to 

 produce a local reaction of moment. Owing to the same cause, an 

 opportunity is here afforded for the escape of some of the spirochetes 

 and their subsequent development. Should the spirochetal focus 

 be very small in comparison to the size of the nerve at the point in 

 question, so that no pressure would result in consequence of the first 

 Herxheimer reaction, there will, of course, be no occasion for the 

 development of acute symptoms. But if, then, the surviving spiro- 

 chetes increase in number a basis would be furnished for what is 

 now commonly termed a neuror elapse. 



When these relapses, which usually occur two or three months 

 or even four or five months after treatment, were first observed, 

 after the use of salvarsan, they were attributed to the contained 

 arsenic and were supposed to constitute a special danger attending 

 its use. But as Ehrlich has pointed out, the same occurrences have 

 been noted in connection with the use of mercury, and to judge from 

 the collective reports of Benario they are no more frequent after the 

 use of salvarsan than after that of the latter, and here as there the 

 same nerves are especially prone to attack, viz., the auditory, the 

 optic, the facial, and the oculomotor, while the fourth, fifth, sixth, 

 and twelfth are much less frequently affected. 



Ehrlich emphasizes in support of his view, that neurorelapses only 

 occur during that period of the disease when there is a maximal 

 distribution of spirochetes, viz., during the early secondary stage, 

 notably in connection with the first exanthem, while during the later 

 stages when actual nerve lesions exist, they are not observed. He 

 regards their occurrence as evidence of a nearly complete sterilization 

 of the body, and very aptly compares the neurorelapse to the extensive 

 development of individual bacterial colonies on agar plates, when 

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