Etiological aspects of gastro-enteritis.

Classification of enteritis presents many difilculties On this subject, Paterson (1933a) said, 'The more one studies the problem of the diarrhoeal diseae ofinfancy, the more complicated it appears ; this same writer (1944) divides gastro-enteritis into three main groups: infective, dietetic, and symptomatic. The first group, which is better called specific, is due to an infection by a known pathogen, such as the Gram-negative bacilli of the coli-typhoiddysentery group. A sub-group of this is the diarrhoea caused by specific infection of other abdominal organs, such as pelvic peritonitis or tuberculous mesenteric adenitis. The second group is due to gross errors in feeding, and is becoming kess common nowadays, as correct knowledge of infant feeding extends through the community. The third group, the commonest, is thought to be due to infection in the body outside the abdomen; this is the 'parenteral tpe.' Campbell and Cunningham (1941) prefer to call this last group 'alimentary-infectious complex, with or without parenteral infection.' This latter name, though vague, seems better than ' parenteral diarrhoea ' in that it recognizes the existence of infection directly influencing the alimentary system and places parenteral infection as a concomitant, rather than a causative disorder. In this senes, ten infants only, out of the total of 148 were suffering from gross dietetic errors; seven recovered and three died. There were but two cases in the ' specific infection ' group: one was suffering from a Salmonella infection, the other from B. dysenteriae Sonne. Each of these had another infection (one respiratory, one dermatitis) and were classed as ' parenteral ' on admission. Two infants who presented as frank dysentery, and eleven who were involved in a small S. aetrycke outbreak (Hinden, 1940) have not been included. It will be seen that the bulk of the patients-136 out of 148 were suffering from ' alimentary infectious' diarrhoea, and of these sixty-six, roughly half, had some form of parenteral infection. These figures will be more fuflly dis later, when the relation of parenteral infection to diarrhoea is dealt with. Advances in classifction will come through splitting off specific types of illness from this omnibus ' group.