ULCERATIVE ENDOCARDITIS. 197 



lining epithelium. In this way the kidneys and liver respectively 

 may be infected. Third, by the blood-vessels : {a) by a few 

 organisms gaining entrance to the blood from a local lesion, and 

 settling in a favourable nidus or a damaged tissue, the original 

 path of infection often being obscure ; {b) by a septic phlebitis 

 with suppurative softening of the thrombus and resulting em- 

 bolism ; and we may add (c) by a direct extension along a vein, 

 producing a spreading thrombosis and suppuration within the 

 vein. In this way suppuration may spread along the portal vein 

 to the liver from a lesion in the alimentary canal, the condition 

 being known as pyelo-phlebitis suppurativa. 



Although many of the lesions produced by the bacteria under 

 consideration have already been mentioned, certain conditions 

 may be selected for further consideration on account of their 

 clinical importance or bacteriological interest. 



Ulcerative Endocarditis. — This condition has been proved to 

 be a bacterial infection of the valves of the heart, and may be 

 produced by various organisms, chiefly pyogenic. Of these the 

 staphylococci and streptococci are most frequently found. In 

 some cases of ulcerative endocarditis following pneumonia, the 

 pneumococcus(Fraenkers) is present; in others pyogenic cocci, 

 especially streptococci. Other organisrris have been cultivated 

 from different cases of the disease, and some of these have 

 received special names ; for example, the diplococcus endocardi- 

 tidis encapsulatus, bacillus endocarditidis griseus (Weichsel- 

 baum), micrococcus zymogenes (MacCallum and Hastings), and 

 others. In some cases the bacillus coli communis has been 

 found, and occasionally in endocarditis following typhoid the 

 typhoid bacillus has been described as the organism present, 

 but further observations on this point are desirable. The gono- 

 coccus also has been shown to affect the heart valves (p. 230), 

 though this is a very rare occurrence. Tubercle nodules on the 

 heart valves have been found in a few cases of acute tuber- 

 culosis, though n.p vegetative or ulcerative condition is produced. 



In some \ s, though we- believe not often, the organisms 

 may attack healthy valves, producing a primary ulcerative endo- 

 carditis, but more frequently the valves have been the seat of 

 previous endocarditis, secondary ulcerative endocarditis being 

 thus produced. In both conditions the affection of the valves 

 usually occurs in the course of suppurative or inflammatory 



