COMPLEMENT FIXATION IN PERTUSSIS 521 



Practical Value of the Complement-fixation Test in Tuberculosis. 

 It is still too early to express an accurate opinion of the practical value 

 of this test; an analysis of numerous reports and my own studies appar- 

 ently warrants the following statements: 



1. A definitely positive reaction taken in conjunction with other 

 findings makes the diagnosis of tuberculosis certain and may be of 

 distinct aid in the diagnosis of early tuberculosis. 



2. From the standpoint of differential diagnosis the test is of value 

 when positive as indicating tuberculosis against other diseases of the 

 lungs, as carcinoma, syphilis, abscess, empyema, etc. 



3. As the reaction is likely to be positive only in active cases, the 

 complement-fixation test is superior to other biologic tests for active 

 tuberculosis, as, for example, the skin test, which is likely to be positive 

 in persons with quiescent lesions. 



4. A persistently and strongly positive reaction probably indicates 

 the presence of active tuberculosis. 



5. The strength of a positive reaction appears to bear some relation 

 to the severity of the disease, and reactions becoming gradually weaker 

 until negative have been frequently noted with clinical improvement 

 and "cure." 



COMPLEMENT FIXATION IN PERTUSSIS 



Investigations on complement fixation with the bacillus of pertussis 

 has given varied results, perhaps due in part to a variation in the cul- 

 tures employed and the methods used to prepare the antigens. 



Bordet and Gengou 1 used suspensions in salt -solution of growths 

 on solid media. Arnheim 2 found negative results with antigens of both 

 the Bordet-Gengou bacillus of pertussis and the influenza bacillus. 

 Wollstein 3 used three forms of antigen: suspensions of the bacilli in 

 salt solution; extracts of bacilli made by suspending the growths of 

 three blood-agar slants in 5 c.c. of salt solution and shaking for twenty- 

 four hours in thermostat; and extracts of tissue obtained from patients 

 dying from pertussis. Friedlander and Wagner 4 used live bacteria and 

 fresh serum, and considered this innovation of great importance. The 

 different hemolytic systems employed may also have had some bearing 

 on the failure to obtain identical results. 



Bordet and Gengou obtained complement fixation in all of their 



1 Ann. de 1'Inst. Pasteur, 1906, 20, 731. 



2 Berl. klin. Wchnschr., 1908, xlv, 1453; Arch. f. Kinderhl., 1909, 1, 295. 



3 Jour. Exper. Med., 1909, 11, p. 41. 



4 Amer. Jour. Dis. of Children, 1914, 8, p. 134. 



