306 



Wound Infection; Suppuration 



Many observations have shown that dire results follow the 

 entrance of this organism into exposed wounds, where it 

 sometimes causes local suppuration, sometimes general in- 

 fection. The streptococci of erysipelas are usually highly 

 virulent. 



BACILLUS PYOCYANEUS (GESSARD). 



General Characteristics. A minute, slender, actively motile, flag- 

 ellated, non-sporogenous, chromogenic and feebly pathogenic, aerobic 

 or facultative anaerobic, liquefying bacillus, staining by ordinary 

 methods, but not by Gram's method. 



In some cases pus has a peculiar bluish or greenish color, 

 which depends upon the presence of Bacillus pyocyaneus 

 (Figs. 94, 95) of Gessard.* 



Distribution. The bacillus appears to be a rather 

 common saprophyte, being found in feces, manure, and 



Fig. 95. Bacillus pyocyaneus. Colonies upon gelatin (Abbott). 



water. It easily takes up its residence upon the skin and 

 mucous membranes, and has been found in the perspiration. 

 It sometimes occurs as a saprophyte upon the surgical 

 dressings applied to wounds, and sometimes invades the 

 tissues through wounds, to occasion dangerous infections. 



Morphology. It is a short, slender organism with 

 rounded ends, measuring 0.3 x 1-2 p-, according to Fliigge, 

 0.6 x 2-6 />-, according to Ernst, and 0.6 x i /*, according to 

 Charrin. It is quite pleomorphous, which probably accounts 

 for the difference in measurements. It is frequently united 



* "De la Pyocyanine et de son Microbe," These de Paris, 1882. 



