294 Wassermann Reaction for Diagnosis of Syphilis 



the complement remained unfixed and acted upon a few of the 

 corpuscles. 



The Validity of the Test. — The Wassermann reaction is not a certain 

 test for syphilis. It is an aid in making the diagnosis, especially 

 in cases in which there are no symptoms. 



Of thousands of bloods of normal persons examined, the results 

 are almost loo per cent, negative. Basset-Smith has had a positive 

 reaction in a case of scarlet fever and one in a case of malignant 

 disease of the liver with jaundice; Oppenheim, one in a case of tumor 

 of the cerebellopontine angle; Marburg, one in a similar case; New- 

 mark reports 2 cases of brain tumors with positive reactions; Cohn, 

 a positive in a patient with a cerebral tumor. The Wassermann 

 reaction is of no value for the differential diagnosis of syphilis and 

 framboesia or yaws. All cases of the latter give a positive reaction. 

 Positive reactions have been found in some cases of nodular leprosy, 

 in a few cases of malaria, in some cases of pellagra, and in a good 

 many cases of sleeping sickness. These seem to form the greater 

 part of positive reactions in non-s)^hilitics thus far recorded. 



In active syphilis Wassermann had 90 per cent, of positive reac- 

 tions in 2990 cases; and most others report about the same. Basset- 

 Smith in 458 such cases found 94 per cent, positive reactions. 



In latent syphilis Wassermann found 50 per cent, positive reactions; 

 Basset-Smith, 46 per cent. 



In chronic, presumably syphilitic, disease of the nervous system, 

 general paresis, and tabes dorsalis the positive reactions vary. In 

 the former disease some have found as high as 90 per cent, positive; 

 in the latter the usual figures vary about 50 per cent. 



It is thus seen that the occurrence of the reaction is much more 

 conclusive evidence of the presence of syphilitic infection than the 

 failure of the reaction is of its absence. 



Treatment greatly influences the test. When under active 

 treatment, either with mercury and iodids or with salvarsan, the 

 reaction of the serums is usually negative. 



Nature of the Reaction. — We now reach the point of considering 

 the nature of the reaction. It is certainly not a variation of the 

 Bordet-Gengou phenomenon. It does not occur because of the 

 presence in the blood of syphilitics of antibodies which combine with 

 the antigen and fix the complement. It is probably not comple- 

 ment fixation so much as complementary inhibition, through the 

 presence in the blood of syphilitics of certain metabolic products, 

 whose action interferes with the complement in some entirely 

 different manner. 



NOGUCHI'S MODIFICATION OF THE WASSERMANN REACTION 



Noguchi* has modified the Wassermann reaction, first by employ- 

 ing as an antigen an extract of the heart of a normal guinea-pig, 

 * "Serum Diagnosis of Syphilis," Philadelphia, 1910, J. B. Lippincott Co. 



