356 EXAMINATION OF PUS 



bered that when plague buboes begin to soften, the plague bacilli may 

 be replaced by ordinary pus organisms. 



It is remarkable how frequently we get pure cultures from abscess material. In 

 purulent material from abdominal abscesses we are apt to obtain mixed cultures, 

 especially the colon bacillus and B. pyocyaneus, in addition to ordinary pus 

 organisms. 



When it is a question between streptococci and pneumococci, it is well to inocu- 

 late a mouse; the capsulated pneumococci at the autopsy make the diagnosis. 



Animal inoculation is also necessary in plague and glanders, and possibly anthrax. 

 When tetanus is suspected, it should be examined for as described under Tetanus. 

 Tuberculosis should also be identified by inoculating a guinea-pig, as well as by acid- 

 fast staining and culture, if there is any doubt as to the nature of the material. 



The black or yellow granules of madura foot, as well as those of actinomycosis, 

 should be examined as recommended in the section on fungi. 



Amcebae, coccidia, and larval echinococci may be found in purulent material, 

 as may also various other animal parasites, as fly larvae, sarcopsyllae, etc. 



The pus from an amoebic abscess of the livei is as a rule sterile when 

 cultured. 



The examination at the time of operation or exploration frequently 

 shows an absence of amoebae as well as of bacteria. Two or three days 

 later amoebae may be found in the pus draining from the abscess cavity. 



Flukes, round- worms, and whip- worms may as a result of their wandering from 

 the intestinal lumen cause abscesses. 



Serious ulcerations may follow infection with the Guinea-worm. 



