MODIFICATIONS OF THE WASSERMANN REACTION 471 



mann reaction, but is a warning that more care is required in making the 

 clinical examination. I have seen a number of such cases in which a 

 positive Wassermann reaction was held a priori as evidence of the syphil- 

 itic nature of a lesion that later proved to be either malignant or tuber- 

 culous. A weak positive reaction, associated with an active ulcerating 

 lesion, very frequently indicates that the lesion is not syphilitic, for 

 active lesions usually yield strongly positive reactions. 



In this connection may also be mentioned the growing importance 

 the Wassermann reaction has assumed in life-insurance examinations. 

 Statistics show that from one-tenth to one-third of all persons infected 

 with syphilis die as the results of the disease, and the death-rate among 

 5000 syphilitics accepted for insurance was one-third over expectation 

 (Brockbank). 



An important question, especially from the standpoint of thera- 

 peutics is: Does a positive reaction invariably indicate the presence of 

 living spirochetes? May the reaction remain positive for an indefinite 

 time after the patient has been cured, just as agglutinins and antitoxins 

 may persist in the blood for some time after recovery from typhoid fever 

 and diphtheria has taken place? The sum total of the experience of 

 investigators from all parts of the world would indicate that a persist- 

 ently positive reaction means the presence of living spirochetes* some- 

 where in the body. The lesions may not be active; the patient, while 

 clinically healthy, may be infective, and is always subject to possible 

 recurrences of clinical syphilis. 



Although gummas are slightly infectious, it is now known that they 

 contain living spirochetes, and the former view, which regarded them as 

 sequels, rather than as actual active lesions of syphilis, is no longer 

 tenable. 



Just how long the reaction may remain positive after the patient is 

 actually cured and all spirochetes are dead is, of course, difficult to state, 

 but experimental studies on the lower animals has shown that the reagin 

 disappears somewhat quickly under these conditions. 



Although a persistently negative reaction is of good prognostic 

 importance, it is not so conclusive in the information it yields as is a 

 positive reaction. In other words, an occasional active lues may react 

 negatively, and not infrequently active syphilitic lesions are found at 

 autopsy in persons whose blood reacted negatively during life. While 

 it is true that great harm may result from a false positive diagnosis due 

 to faulty technic, yet it must be admitted that the Wassermann reac- 

 tion is not too delicate, and that we are just as prone to err on the side 



