PHAGOCYTOSIS 



269 



enough opsonin in the blood; it must reach the diseased 

 tissue. 



Some observations go to show that it may be unable to do 

 this under certain conditions. Thus Bulloch found the liquor 

 puris from a staphylococcic abscess entirely devoid of opsonin to 

 staphylococci. This might have been due to absorption by the 

 bacteria in the pus, so he cleansed the abscess, and, taking the 

 first few drops which collected, found them also very deficient 

 in opsonin. It appears, therefore, that this substance, though 

 present in the blood, was unable to make its way through the 



FIG. 62. SHOWING INVERSE RELATIONSHIP BETWEEN TEMPERATURE AND 

 OPSONIC INDEX IN PHTHISIS. (Inman.) 



The continuous line shows the temperature. 



wall of the abscess to the place where it was wanted. Again, 

 Wright has shown that the serous fluid in cases of tuberculous 

 pleurisy and peritonitis is very low in opsonin as compared with 

 the circulating blood, and has made use of this fact as a means 

 of diagnosis. It must be obvious that in the case of an extra- 

 vascular object like a tubercle, and especially a caseous mass, 

 that a slight alteration in the opsonic index of the blood can 

 have but a slight immediate effect ; any beneficial effect of a 

 high index must be slow in manifesting itself. To remedy this, 

 Wright attempts to flush the morbid tissues with blood or lymph 



