In adult life the nervous person when subjected to excessive stress and strain is seldom free from dyspeptic symptoms of one sort or another, and what is true of adult life is even more true of childhood, when the emotions are more poignant and less controlled. Then tears flow more readily than in later life, and tears are not the only secretions which lie under the influence of strong emotion. Emotional states, which would stamp a grown man as a profound neurotic, are almost the rule in infancy and childhood, and may be marked by the same physical disturbances—flushing, sweating, or pallor, by the discharge of internal glandular secretions as well as by inhibition of appetite, by vomiting, gastric discomfort, or diarrhoea. Naturally enough, mothers and nurses are wont to demand a concrete cause for the constant crying of a little child, and teething, constipation, the painful passage of water, pain in the head, or colic and indigestion are suggested in turn, and powders, purges, or circumcision demanded. There can be no doubt that nervous unrest is capable of producing prolonged dyspepsia in infancy and childhood—a dyspepsia which, while it obstinately resists all attempts to overcome it by manipulation of the diet, is very readily amenable to treatment directed to quiet the nervous system.
Where a primary dyspepsia exists for any length of time, the growth and the nutrition of the child is clearly altered for the worse. The character of the stools, their consistency, smell, and colour, is apt to be changed because the bacterial context of the bowel has become abnormal. Rickets, mucous disease, lienteric diarrhoea, infantilism, prolapse of the rectum, and infection with thread-worms are common complications. No doubt children with primary dyspepsia are often nervous and restless, and the elements of infection and of neurosis are frequently combined. Yet often we meet with cases in which the gastric or intestinal disturbance comes near to being a pure neurosis. The nutrition, then, seldom suffers to any very great extent, or to a degree in any way comparable to that which is characteristic of dyspepsia from other causes. Emaciation, wrinkling of the skin, dryness and falling out of the hair, decay of the teeth, are not as a rule part of the picture of nervous dyspepsia. The child may be slim and thin and nervous looking, but as a rule he is active enough, with a good colour and fair muscular tone, so that one has difficulty in believing the mother’s statements, which are yet true enough, as to the trouble which is experienced in forcing him to eat, or as to the frequency of vomiting.