512 Pneumonia 



Howard* has also called attention to the importance of 

 this bacillus in connection with numerous acute and chronic 

 infectious processes, among which may be mentioned 

 croupous pneumonia, suppuration of the antrum of High- 

 more and frontal sinuses, endometritis, perirenal abscesses, 

 and peritonitis. 



Virulence. The virulence of the organism seems to vary 

 under different conditions. It is sometimes harmless for 

 the experiment animals, but when injected into mice and 

 guinea-pigs usually produces local inflammatory lesions, and 

 sometimes invasion of the circulation and death from sepsis. 



CATARRHAL PNEUMONIA OR BRONCHOPNEUMONIA. 



This form of pulmonary inflammation occurs in local 

 areas, commonly situated about the distribution of a bron- 

 chiole. It cannot be said to have a specific micro-organism, 

 as almost any irritating foreign matter accidentally inhaled 

 may cause it. The majority of the cases, however, are 

 infectious in nature and result from the inspiration, from 

 higher parts of the respiratory apparatus, of the staphylo- 

 cocci and streptococci of suppuration, Friedlander's bacillus, 

 the bacillus of influenza, and other well-known organisms. 



TUBERCULAR PNEUMONIA. 



The progress of pulmonary tuberculosis is at times so 

 rapid that the tubercle bacilli are distributed with the 

 softened infectious matter throughout the entire lung or to 

 large parts of it, and a distinct pneumonic inflammation 

 occurs. Such a pneumonia may be caused by the tubercle 

 bacillus, but more frequently depends upon accompanying 

 staphylococci, streptococci, tetragenococci, pneumococci, 

 pneumobacilli, and other organisms accidentally present in 

 a lung in which ulceration and cavity formation are ad- 

 vanced. 



PLAGUE PNEUMONIA. 



The pneumonic form of plague is characterized by con- 

 solidation of the lung histologically and anatomically, indis- 

 tinguishable from pneumococcal and other extensive pul- 

 monary infections. 



* "Phila. Med. Jour.," Feb. 19, 1898, vol. i, No. 8, p. 336. 



