1832 



THE DYSENTERIES 



Amoebic Fever or General Amcebiasis. — This term has been appHed 

 to certain cases of L. histolytica infections in which there is fever, but 

 no dysenteric symptoms and no sign of hepatitis. A few cysts are 

 generally found in the stools, and emetine induces a prompt dis- 

 appearance of the fever. 



CJomplications. — The most usual complication is hepatitis and 

 hepatic abscess; more rarely gangrene of the bowel and peritonitis 

 may supervene during an attack; while haemorrhage is a most 

 unusual complication. The hepatitis is recognized by the tender- 

 ness in the right hypochondrium and by the rise in the temperature, 

 but it and the hepatic abscess will be discussed in a subsequent 

 chapter. In Ceylon we have observed cases of mixed infection, 

 dysentery and enteric, the two infections developing apparently 

 contemporaneously. 



Sequelse. — The important sequel to an attack of amoebic dysen- 

 tery is liver abscess, but abscesses in other parts of the body such 

 as the spleen may be met with. Stenosis of the sigmoid colon, due 

 to cicatrization of the healing ulcers, is well known, and will be 

 dealt with under the heading of Bacterial Dysentery. Sprue is 

 often said to be a sequel of dysentery, but this must be considered 

 to be doubtful. Certain authors have described a persistent 

 bradycardia. 



Diagnosis. — The diagnosis between bacterial and amoebic dysen- 

 tery by clinical phenomena only is, in our opinion, impossible in 

 most cases, though several observers have attempted to define 

 some differential points. These authors state that amoebic 

 dysentery is to be distinguished from bacillary dysentery by its 

 chronic course, its rare pyrexia, and the absence of toxic 

 symptoms, while it is often followed by liver abscess. Apart from 

 the last feature, the other so-called differential signs have, in 

 our experience, no importance, as we have come across ex- 

 tremely acute cases of amoebic dysentery with fever and toxic 

 symptoms. 



The only certain method of diagnosis is by the discovery of 

 Loeschia histolytica in the stools, and this should be done by picking 

 out and examining any mucus which may be seen. It is of practical 

 importance to distinguish between L. histolytica and the harmless 

 L. coli, and this differentiation may at times be difficult. The former 

 is often larger, and possesses an ectoplasm, which is easily differ- 

 entiated from the endoplasm; it is more actively motile than 

 L. coli, and often contains erythrocytes, which is the most important 

 character. The nucleus of L. histolytica is eccentric, smaU, and 

 generally indistinct, does not stain deeply, and has very little 

 chromatin (see p. 313). 



In order to expedite the diagnosis the French method is to add 

 a drop of a I per cent, solution of methylene blue to the mucus 

 before placing on the coverslip, when the pus and epithelial cells 

 will be stained, and the amoebae more easily recognized as unstained, 

 clear objects. 



