80 PROTOZOAN PARASITISM 



The characteristic pathology of the condition is 

 as described by Councihiian and Lafleur (1891), with 

 the undermining and tunnelling ulcer of the sub- 

 mucosa, distributed mainly in the caecum and as- 

 cending colon but not uncommonly involving the 

 whole large intestine and extending over the ileocae- 

 cal valve. Penetration of the wall with perforation, 

 peritonitis, extension into the meso-colon and re- 

 troperitoneal tissues, liver abscess, and rarely more 

 distant amoebic abscesses may occur during its 

 course. 



As the condition becomes prolonged, healing of 

 ulcers and the formation of fibrous adhesions between 

 the intestinal coils and surrounding viscera may pro- 

 duce extensive matting of the abdominal viscera and 

 deformity of the intestine. 



The "moth-eaten" appearance of the colon at 

 autopsy is typical and not to be confused with ulcera- 

 tive colitis of other origin. 



Among the symptoms of the disease, dysentery, 

 with numerous blood-stained mucous stools, '' bloody 

 flux," is outstanding. It is reported that acute amoe- 

 bic colitis may occur without dysentery and the 

 characteristic stool, and I have done autopsies on 

 cases dead of the condition, in whom there was no in- 

 formation of diarrhoea or dysentery. It is not im- 

 probable that dysentery has existed in some persons, 

 the condition of whom at the time of observation 

 precluded the possibility of obtaining correct informa- 

 tion. Involvement of the rectum produces pam. 



