PATHOGENIC PROPERTIES. 305 



In a certain number of cases 1 diphtheria bacilli have 

 been found in the blood and internal organs of individ- 

 uals dead of the disease, but all that has been learned 

 from careful study of the secondary manifestations of 

 diphtheria tends to the opinion that they are in no way 

 dependent upon the immediate presence of bacteria, and 

 that the occasional appearance of diphtheria bacilli in 

 the internal organs is in all probability accidental, and 

 usually unimportant. 



By special methods of inoculation 1 (the injection of 

 fluid cultures into the testicles of guinea-pigs) diphtheria 

 bacilli can be caused to appear in the omentum, but this 

 is purely an artificial manifestation of the disease and 

 one that is probably never encountered in the natural 

 course of events. Very rarely similar results follow 

 upon subcutaneous inoculation. 



If a very minute portion of either a solid or fluid 

 pure culture of this organism be introduced into the sub- 

 cutaneous tissues of a guinea-pig or kitten, death of the 

 animal ensues in from twenty-four hours to five days. 

 The usual changes are an extensive local oedema, with 

 more or less hyperemia and ecchymosis at the site of 

 inoculation ; swollen and reddened lymphatic glands ; 

 increased serous fluid in the peritoneum, pleura, and 

 pericardium ; enlarged and hemorrhagic ad-renal bodies; 

 occasionally slightly swollen spleen ; and sometimes 

 fatty degeneration in the liver, kidney, and myocar- 

 dium. In guinea-pigs, especially, the liver often shows 

 numerous macroscopic dots and lines on the surface and 

 penetrating the substance of the organ. They vary in 

 size from a pin-point to a pin-head and may be even 



1 Abbott and Ghriskey : A Contribution to the Pathology of Experimental 

 Diphtheria. The Johns Hopkins Hospital Bulletin, No. 30, April, 1893. 



