To these groups we must add a fourth, comprising those cases which assume a chronic type, and are not infrequently met with as the sequelm of one of the preceding forms. With this group, as with the others, we can draw no definite dividing-line separating it sharply from the more acute cases. Holt terms those cases chronic which have persisted longer than six weeks. Some cases, however, assume the type of chronicity sooner, even, than this. In them the signs of active inflammation subside, the appetite partially returns; the diarrhoea, though lessened, still persists and is associated in some instances with a varying amount of ulceration of the intestinal wall, in others with a more or less atrophic con dition of the intestinal glands. In the latter variety the progressive emaciation indicates how serious is the interference with the processes of digestion and ab sorption.
These somewhat provisional groups may be tabulated as follows:— 1. Functional diarrheas, non-inflam matory in character.
2. Inflammatory diarrheas, in which the symptoms of a toxic systemic infec tion are predominant.
3. Inflammatory diarrheas, in which in addition to the systemic infection the symptoms of an acute local inflammation have a prominent part.
4. Chronic diarrheas, in which the acute inflammatory symptoms have more or less subsided, but in which the stools remain abnormal both in character and frequency, and emaciation is apt to supervene.
Functional cases of infantile diarrhoea are met with which cannot be otherwise regarded than as purely functional in character. During dentition a moderate increase in peristal sis and secretion is sometimes noted which it is difficult to attribute to any fault in diet, and which promptly sub sides on the eruption of the teeth. In a few instances a similar condition may be induced by impulses acting thiough the nervous system, such as fright, over excitement, and a sudden chill to the surface of the body. At other times these same causes appear to produce their effect chiefly by disturbing digestion. Substances also may occasionally be ' given as food to the infant which act as direct mechanical irritants to the sensi tive mucous membrane of the alimentary tract.
In this group are also to be. placed many diarrhceas met with in breast-fed infants, where, owing to a faulty dietary or mode Of life, or to nervous overstrain on the part of the mother or nurse, the breast-milk becomes altered, resulting in either gastric or intestinal indigestion followed by diarrhoea. The time of wean
ing is similarly one of peculiar suscepti bility. Infants artificially fed suffer sometimes from this form of the disease; in them any error in the preparation or administration of their food may be fol lowed by an attack of diarrhea. In such, however, these attacks are more liable than in the breast-fed to assume an in flammatory type. This liability is still further increased by all conditions lower ing the digestive powers.
some instances the diarrhoea may commence quite suddenly with large more or less fluid motions, containing, besides facal matter, con siderable undigested material. In other cases symptoms of gastric irritation and abdominal pain precede for some hours the diarrhoea. Examination of the in fant generally reveals a moderate amount of pyrexia: 100° to 102° F.; rarely does the temperature run higher except in cases of sudden onset with severe gastric disturbance. Slight abdominal disten sion may often be noted. The stools are frequent, thin, usually sour-smelling, and of varying color. In young infants on an exclusive milk diet, they are, in general, of some shade of green and of a distinctly acid reaction; occasionally, however, they are gray or chalky in color and frothy in character. In older infants, on a more mixed diet, the stools may have no uni form color, but be in part green and in part some shade of brown, and of a very unpleasant odor. Examination under the microscope reveals, besides undi gested material, only those forms of bac teria met with in normal faeces. The infant is peevish and may either refuse its food altogether or drink a part greedily to allay its feverish thirst, and then refuse the remainder. Should the pyrexia run high, nervous symptoms may manifest themselves in twitching of the limbs, prostration, and wakefulness.
The attack in this type of the disease is of brief duration. After the diarrhoea has continued for some hours the tem perature generally falls; nervous symp toms, if present, pass away; the motions in a few days become less frequent and gradually resume their normal appear ance; and the desire for food becomes more imperative.
Diagnosis,—At the onset, unless from the history of the case, it is impossible to predict with certainty just what we may have to deal with. It must be membered that symptoms similar to the above may not infrequently usher in a severe constitutional disorder.