280 IMMUNOLOGICAL METHODS OF DIAGNOSIS 



myself that a triple plus (+ + +) reaction can ever be ascribed to 

 the malignant process in itself. Partial reactions (+ or ), on the 

 other hand, are here not infrequently met with and may even be 

 seen in persons who neither show any present signs or give any 

 history of syphilis in the past. What these feeble reactions mean 

 I do not know, but I am inclined to think that they may possibly 

 be the expression of some inherited syphilitic taint, though I have 

 but few data to support this belief. As the result of a fairly wide 

 experience with the reaction I have come to the conclusion that from 

 the diagnostic standpoint triple plus reactions only should be con- 

 sidered as positive evidence of syphilis, while the feebler grades, in 

 individuals with an admitted history of the disease, may be regarded 

 as indicating that the infection is probably limited to relatively 

 small areas, from which an insignificant absorption of spirochetal 

 substance is taking place, with a correspondingly limited formation 

 of the lipoidophilic antibody. If the actual focus of infection should 

 be sufficiently restricted it is, of course, conceivable that a negative 

 reaction even might be obtained, and it is for this reason that a 

 single negative reaction has a limited value only from the standpoint 

 of diagnosis, as well as of treatment. As I have pointed out in a 

 previous chapter, however (see section on Salvarsan), it is frequently 

 possible by the administration of a few large doses of mercury to 

 evoke a positive reaction in individuals in whom the disease has 

 almost been eradicated, whereby a larger number of spirochetes is 

 destroyed at one time arid a more intense stimulus given to antibody 

 formation (prowcatory stimulation}. This possibility has not yet 

 received the recognition which it deserves, but should be utilized in 

 all doubtful cases, as well as in determining whether a continuance 

 of treatment is desirable or not (see page 259). 



In very early cases of syphilis, in which a sufficient length of time 

 for the formation of antibodies has not yet elapsed, the result will, of 

 course, also be negative, but in these the diagnosis can usually be 

 made by direct demonstration of the spirochete with the microscope. 



With the limitations just set forth a diagnosis of syphilis can be 

 reached by means of the Wassermann reaction in over 90 per cent, 

 of the cases taken at random, the different types giving different 

 values, as shown in the accompanying table, which is taken from 

 Noguchi. The values given were obtained with the Noguchi system, 

 i. e., with an antihuman hemolytic system, but represent practically 

 what the method furnishes which I have described above. 



