SECTION III 



COLLECTION AND EXAMINATION OF CERTAIN 

 MORBID MATERIALS 



THE COLLECTION AND EXAMINATION OF PUS 



When a simple microscopical examination has to be made, the 

 collection of pus presents no difficulties, as the few bacteria 

 which may gain access from the skin or the air will not lead to 

 error. The case is otherwise where cultural examinations have 

 to be made, or where the material has to be taken to a laboratory. 

 Here the material should be collected in a pipette. This is to 

 be at hand when the abscess is opened ; both ends are to be 

 broken off and passed through the flame two or three times. The 

 pipette should then be held by an assistant, or put with the end 

 which is to be inserted into the pus projecting over the side of the 

 table, so as not to come into contact with any object. 



When the abscess has been opened, a considerable quantity of 

 pus should be allowed to flow out, and the sterilized pipette is 

 then to be passed through the incision (care being taken to avoid 

 contact with its sides) and the pus carefully sucked up into the 

 bulb. The fluid thus obtained may be used to inoculate cultures 

 there and then, or both ends of the pipette may be sealed in the 

 flame. 



The Examination of Pus. 



The organisms which may cause pus are extremely numerous, 

 the most important being streptococci, staphylococci, the pneumo- 

 coccus and the gonococcus, the bacilli of typhoid fever, tubercu- 

 losis, and glanders, the B. coli communis, the B. pyocyaneus (the 

 organism which produces blue pus), and the fungus of actino- 

 mycosis. In the majority of cases the organism which is present 

 in a given sample of pus can be determined by a microscopic 

 examination of films prepared in the usual way and stained by a 



