292 Wassermann Reaction for Diagnosis of Syphilis 



The serum to be tested is drawn into a second finely graduated 

 pipette, and 0.2 cc. added to tubes i, 2, and 9, and that pipette 

 laid aside. 



The positive syphilitic serum used to control the test is similarly 

 drawn up in a fresh pipette and 0.2 cc. of it measured into tubes 

 3 and 4, and the pipette laid aside. 



The normal serum used as a control is similarly drawn into still 

 another pipette and 0.2 cc. measured into tubes 5 and 6, and the 

 pipette laid aside. 



The alcoholic extract composing the antigen is next added, either 

 by diluting it so that i cc. contains the unit, or measuring the unit 

 quantity directly into the tubes. The antigen is added to tubes 

 i, 3, 5, and 7, and the pipette laid aside. 



Lastly, each tube receives a correctly measured quantity of 0.85 

 per cent, sodium chlorid solution to bring the total bulk of fluid up 

 to exactly 3 cc. 



Each tube is now shaken carefully, so as not to cause frothing of 

 the fluid, and the rack is stood in a thermostat kept at 37C. 



At the end of an hour the rack is removed, and every tube receives 

 the addition of i unit of the sheep corpuscle suspension and, with 

 the exception of tube 9, receives one dose of amboceptor, either the 

 serum measured by diluting so that i cc. equals the dose, or the 

 necessary square of paper. This, in the former case, brings the total 

 bulk of fluid to 5 cc., in the latter makes it necessary to add i more 

 cubic centimeter of salt solution to each tube. We aim to have 

 exactly 5 cc. of fluid in each tube. 



The tubes are again stood in the thermostat, where they are per- 

 mitted to remain for an hour, when the readings are taken and 

 carefully noted. After this the rack and all the tubes are placed 

 in the ice-box until twenty-four hours old, when the final readings 

 are taken and the conclusions are reached. 



As a rule, the readings taken after the second hour of incubation 

 and those taken after twenty-four hours correspond. 



A valid test should show the following: 



Tubes 



1. No hemolysis in syphilis. Hemolysis in health. 



2. Complete hemolysis. 



No hemolysis (this is the standard of comparison). 



Test Controls. 



4. Complete hemolysis. 



9. No hemolysis, as a rule. 



In the tubes in which hemolysis takes place the change is very 

 marked. The hemoglobin dissolves out of the corpuscular stroma 

 and saturates the fluid, transforming it from the opaque pale red 

 to a transparent Burgundy red. Sometimes the corpuscular 



