On Tubercular Infection in a Patient's Blood, etc. 



195 



This " pooled serum " was obtained by mixing equal volumes of the sera of 

 six to eight healthy students or laboratory workers. We have found that the 

 opsonic power of such a " pooled serum " corresponds to the arithmetical mean 

 of the opsonic indices of its component sera. 



Classification of Tubercular Cases into Strictly Localised Cases, and Cases which 

 are associated with Constitutional Disturbance. 



Cases of tubercular infection distribute themselves in a natural manner 

 under two headings. Into one category would fall the patients who are the 

 subjects of a strictly localised infection unaccompanied by anything in the 

 nature of constitutional disturbance. Cases where the infection is limited to 

 one or more lymphatic glands ; further, most cases of lupus, most cases of 

 tubercular abscess in the subcutaneous tissue, tubercular affections of the 

 joints, and, lastly, many stationary or only slowly progressing cases of 

 tubercular phthisis, fall into this category. 



Into another category would fall patients who are suffering from more 

 generalised tubercular infections associated with constitutional disturbance. 

 This group consists in large part of cases of pyrexial pulmonary tuberculosis. 

 With these may be classed certain other cases of extensive or widely dis- 

 seminated tuberculosis. 



Data with regard to the Tuberculo-opsonic Power in Cases of Strictly Localised 



Tuberculosis. 



The opsonic index is here low and uniformly low — in exceptional cases as 

 low as one-sixth of the normal. Our findings in a series of cases of strictly 

 localised tubercular infection are appended in tabular form below. 



sive series of investigations carried out by Bulloch at the London Hospital ('Medieo- 

 Chirurg. Soc. Proc.,' 1905), and Lawson and Stewart at the Banchory Sanatorium (loc. 

 cit.), have conclusively shown — (a) That the tuberculo-opsonic power of the blood does 

 not in health range below - 9 or above Tl ; and (6) that the bloods of A. E. W., S. R. D., 

 and others which have hitherto in this laboratory furnished a standard of comparison, 

 are, from the point of view of their tuberculo-opsonic power, typically normal bloods. 



