REACTIONS DEPENDING UPON COMPLEMENT FIXATION 315 



rate until the B tubes show complete hemolysis. After that some 

 writers recommend that all the tubes be placed on ice and examined 

 the next morning. I can see no advantage in this delay, and prefer 

 to centrifugalize and read them at once. 



RESULTS. Complete inhibition or absolute fixation is, of course, 

 at once evident from the fact that the supernatant fluid (after cen- 

 trifugation) is perfectly colorless, the corpuscles being all at the 

 bottom. Partial fixation will show itself by a more or less colored 

 supernatant fluid and the presence of a varying number of undis- 

 solved red cells at the bottom, while with complete hemolysis there 

 is no sediment of red cells whatever. The results are accordingly 

 noted as + + +,++,+, , and (see Plate VI). 



While the controls will usually be found hemolyzed completely, 

 sera are at times, though rarely, met with which fix more or less 

 completely by themselves. Such reactions are now interpreted as 

 indicating that the serum contains not only the lipoidophilic anti- 

 body but the corresponding lipoid is well, and hence as equivalent 

 to a positive reaction. 



Regarding the value of the Wassermann reaction, both from the 

 stand-point of diagnosis and in its bearing upon the question of 

 treatment, we would emphasize that its neglect in a doubtful case 

 from either point of view would constitute a grave Kunstfehler, 1 as 

 the Germans put it, of which, very fortunately, but few modern 

 physicians are apt to be guilty. 



Considered from the diagnostic stand-point a well-pronounced 

 positive reaction may probably always be regarded as indicating the 

 existence of syphilis, if we can rule out such diseases as framboesia, 

 leprosy, sleeping sickness, and scarlatina. In malignant disease a 

 certain degree of complement-fixation may also be obtained, in a 

 considerable number of cases, but I have not been able to convince 

 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 nor give any 

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



1 An error of omission would approximately express the idea in our own 

 language. 



