EXAMINATION OF THE BLOOD. l6g 



The practitioner is recommended to practice this 

 method of staining, as it does not require any reagents 

 which are not to be found in every well stocked surgery. 

 The watery solution of methylene blue which is used as 

 a counterstain for the tubercle bacillus and some red ink 

 are all that are necessary. 



THE BACTERIOLOGICAL EXAMINATION 

 OF THE BLOOD. 



The bacteriological examination of the blood is not of 

 very great diagnostic importance, as it is only in a very 

 few diseases that pathogenic bacteria are present in the 

 circulation in such quantities as renders the search for 

 them in the minute amounts which are withdrawn for 

 examination at all promising. 



The chief organisms which have been found in the 

 blood are : 



i & 2. Streptococci and staphylococci. These are found 

 in cases of septicaemia, pyaemia, ulcerative endocarditis, 

 &c. ; they always indicate an extremely bad prognosis. 

 The chief importance which attaches to the discovery 

 of these organisms is that it absolutely settles the 

 diagnosis (always provided that there are no errors in 

 technique) and that it indicates whether the use of anti- 

 streptococcic serum is advisable or not ; it is useless in 

 cases of septicaemia, &c., which are not due to strepto- 

 cocci. 



A word of warning is necessary in the interpretation 

 of results which indicate that staphylocci are present in 

 the blood. These organisms are constantly present in 

 the skin and may be found in film preparations or in 



