DIFFERENTIAL DIAGNOSIS OF THE DYSENTERIES 217 



findings. Accordingly, work on the feces and bowel exudates 

 should be done with the greatest thoroughness and accuracy. 

 Needless to say, such work should only be undertaken by a per- 

 son of broad knowledge and experience. The bowel contents should 

 be studied daily during the course of the investigation. 



There is not space here to go into the technique of coprology. 

 Consequently I shall only emphasize a few points, and earnestly 

 urge the careful study of the methods set forth in Cammidge's 

 admirable book (1914). The recent literature on biochemistry, 

 nutrition and related subjects also should be consulted. Inci- 

 dentally, I might point out there is great need for revision and 

 systematization of the terminology of coprology. 



Collecting the Specimen. I know of nothing more important in 

 such work than the proper collection of bowel evacuations. The 

 microscopist should be satisfied with nothing less than the entire 

 movement. A portion of the movement selected at random by a 

 nurse or by the patient himself, far from yielding adequate in- 

 formation may even be misleading. Some stools consist of separate 

 formed and unformed portions. If the microscopist receives a 

 sample of the formed portion he records the stool as normal and 

 knows nothing of the pathological elements that may be in the 

 other portion. If he receives the unformed portion he records the 

 stool as diarrheal and possibly misses other equally interesting 

 things. The stool should not be allowed to stand after its passage, 

 but should immediately be sent to the microscopist. 



Preferably, the movement should be obtained without the aid 

 of artificial means. All are objectionable. Castor and mineral oils 

 offer great obstacles to microscopic work. The drastic purgatives 

 produce watery stools that complicate the picture in many ways 

 and add greatly to the difficulty of fixation and staining of the 

 material on the slide or coverglass. Watery movements very rap- 

 idly bring about changes in delicate organisms that render them 

 unfit for study. Enemata are quite as bad. When there is difficulty 

 in getting a specimen, a glycerine suppository sometimes will 

 stimulate the lower bowel to activity. A full dose of strychnine 

 sulphate often is effective. When these things fail, one may give 

 fluid extract of cascara in very moderate dosage, or a merely laxa- 

 tive dose of Carlsbad water. The latter I prefer to am^hing else, 

 but it must not be given in sufficient quantity to produce a watery 

 movement. The point is to obtain a movement with the least 



