# Tropical Diseases/Chapter 31

CHAPTER XXXI
HILL DIARRHŒA
Definition.— A form of morning diarrhœa accompanied by flatulent dyspepsia and the passage of copious, liquid, pale, frothy stools. It occurs principally in Europeans on their visiting the hills after residing for some time in the hot lowlands of tropical countries.
Geographical and seasonal distribution. —Crombie, who gave an excellent account of this disease, pointed out that a similar affection may show itself in the highlands of Europe as well as in those of India. It is said also to occur in corresponding circumstances in South Africa and South America. There is no reason, therefore, to suppose that hill diarrhœa is special to India, although, owing to the large European population frequenting the hill sanitaria in that country, it has been particularly noticed there. An elevation of 6,000 feet or over, when combined with an atmosphere saturated with watery vapour, is particularly favourable to its development. In India it is found to begin and end with the rains, during which, in certain years and places, it is apt to assume almost epidemic characters. Thus, during the wet season of 1880, in Simla an epidemic of hill diarrhœa affected from 50 to 75 per cent, of the population, three-fourths of the cases happening within a week of each other. In some years hill diarrhœa is less prevalent than in others; but at the proper season few of the various hill sanitaria of India are without examples.
Etiology and pathology.— It is difficult to say what may be the precise factors determining this disease. The low barometric pressure associated with great elevation above the sea-level may be a favouring circumstance. Damp seems to be indicated by the ​fact that the disease occurs principally during the rains. Chill after exposure to the high temperature of the plains has possibly an important share. Manifestly there is a suspension of the functions of the liver and, considering the dyspepsia and looseness, most probably of those of the pancreas and of the other glandular structures subserving digestion. Hill diarrhœa is certainly something more than an intestinal catarrh. As Crombie pointed out, it is more in the nature of dyspepsia. There are no adequate grounds for connecting it with either the water or the food supply. The question of micro-organisms has, apparently, not been studied.
Symptoms.— Without very obvious cause the patient, who in other respects may be in good health, soon after arrival at a hill sanitarium becomes subject to a daily recurring diarrhœa, the looseness coming on regularly every morning some time between 3 and 5 o'clock. The calls to stool are apt to be sudden and imperative. The motions passed are remarkably copious; very watery in some instances, pasty in others. They are pale, frothy, and like recently stirred whitewash, so devoid are they of biliary colouring matter. Their passage is attended with little or no pain, often with a sense of relief. From one to half a dozen, or more, such stools may be voided before 11 a.m. After that hour, at all events in ordinary cases, the diarrhœa is in abeyance for the rest of the day, and the patient may then go about his duties or pleasures without fear of inconvenience.
The distinctive features of this form of diarrhœa are, therefore, the regularity of its recurrence every morning and its cessation after a certain hour in the forenoon; the absence of colour in the stools; and the attendant flatulence. The abdomen is sometimes blown out like a drum, the patient being conscious of unpleasant borborygmi associated with a feeling as of some boiling or chemical operation proceeding in his inside. Occasionally cases are met with in which the stools are very pale although there is no diarrhœa.
Under treatment, or spontaneously, or, according to Crombie, on acclimatization occurring, after some ​days or weeks the diarrhœa may subside. In other instances it persists, in defiance of treatment, until the return of the patient to the warm plains, when it at once spontaneously subsides. Crombie instanced a case in which the patient was regularly attacked with hill diarrhœa whenever he visited Simla— twelve occasions— recovery invariably taking place on his return to the plains. If the looseness is both considerable and protracted, there necessarily ensue debility, wasting, and anæmia, and the disease may lapse into confirmed sprue— an affection having, apparently, close affinities with hill diarrhœa.
Treatment.— The treatment recommended by Crombie, and endorsed by other medical men of experience in India, consists in a pure milk diet, rest, warm clothing, a teaspoonful of liquor hydrargyri perchloridi in water about fifteen minutes after food, and 12 gr. of pepsin, or a corresponding quantity of lactopeptin or ingluvin, two hours later. If, in spite of treatment, the disease persists, the patient must return to the low country.