Intestinal autointoxication is a toxaemia resulting from absorption of abnormal food products formed within the alimentary canal by bacterial action. This definition excludes ptomaine poisoning, milk, fish, and meat poisoning, etc. - conditions due to ingestion of already poisoned substances. Autotoxaemia disturbs the vascular, nervous, digestive, and eliminative functions, and the toxins may be demonstrated in the stomach contents, faeces, and urine. The symptoms are due to: 1, fermentation; 2, putrefaction.

1. Fermentation Symptoms

Fermentation Symptoms are caused by the fermentation products of carbohydrate food, principally-C02 and organic acids, such as lactic, acetic, and butyric chiefly, and to some extent formic, succinic, valerianic, propionic acids, and acetone. Alcoholic fermentation is also present. These symptoms are in part mechanical, due to pressure from gas; such are: eructations, stomach and intestinal tympanites, palpitation, flatus, abdominal tenderness, and irregular stools. In addition there may be nausea, vomiting, a foul odour in the breath and faeces. With the exception of oxalic acid in oxaluria, fermentation products are not recovered from the urine to any extent, as the ultimate products of carbohydrate food are C02 and water. Slight fever may be present.

The severity of fermentation autointoxication symptoms depends upon: (I) the composition of foods, (2) the variety of foods, (3) the number and kind of bacilli introduced with the food, (4) the reaction and quantity of the gastric juice, (5) the motility of the stomach, and (6) the rate of absorption of fermentation products.

2. Putrefaction Symptoms

Putrefaction Symptoms are caused by intestinal putrefactive processes involving the proteid foods, and resulting in the formation of nitrogen and sulphur compounds, chiefly of the aromatic series; such are: indol, cresol, phenol, skatol, with hydrogen sulphide gas as a by-product, free nitrogen and hydrogen. Other less important products are: putrescin, cadaverin, neurin, leucin, cystin, methyl, mercaptan, and carburetted hydrogen. Excess of H2S produces hydrothionanaemia. The putrefactive bacillary processes take place mainly in the colon, but may extend to the small intestine and stomach. In general the symptoms of putrefaction are more distinctly toxic and less mechanical (less gas is formed) than those of fermentation. The effects of putrefaction are especially manifest upon the blood and nervous system. C. H. Herter gave indol experimentally to several persons, with the effect of producing such symptoms as frontal headache, vertigo, restlessness, insomnia, frequent micturition, diarrhoea, and finally a condition of neurasthenia. Indol is derived from the tyrosin of proteid food, through action of the colon bacillus, but it is not derived in any quantity from milk.

It is closely related to indican formation.

Neurin is another highly toxic intestinal product formed sometimes in cases of intestinal obstruction, and derived from lecithin in egg yolk and from other sources. According to Herter, in man it causes increased peristalsis, diarrhoea, abdominal cramps, and lessened heart force and pulse tension.

As the nitrogen and sulphur of putrefactive products are eliminated through the kidneys as ethereal sulphates, etc., unlike the carbohydrate final products, it becomes comparatively easy to detect them and trace their relationship to special articles of diet.

The clinical results of autointoxication may be immediate or acute and violent, with much gastrointestinal disturbance, or they may be remote, i. e., chronic. In the latter instance such conditions are associated as neuritis, neuralgias, tetany, epilepsy, anaemia, arteriosclerosis, skin eruptions like eczema, acne, pruritus, and exfoliative dermatitis, tetany, poliomyositis, psychoses, melancholia and neurasthenia, and miscellaneous toxaemias like goutiness and lithaemia. It is not claimed, of course, that intestinal autointoxication is the sole cause of all these conditions, but it is usually associated with them, often both antedates them and makes them worse, and they are capable of improvement under dietetic regulation.

It should be observed that in many cases of intestinal autointoxication the primary digestive disorder may be in the stomach. Hastily eaten food, coarse or indigestible food which is imperfectly digested in the stomach, passes into the intestine in a condition which may give rise to much irritation, and if many bacteria are present, to the development of a variety of more or less toxic products. Similarly, hyperacidity, and especially hypermotility of the stomach, which causes the food to pass too quickly into the intestine, may result in intestinal autointoxication.

The foul breath which often characterises this condition is in part due to the elimination through the lungs of hydrogen sulphide gas, which, after absorption by the intestinal vessels, is conveyed to the pulmonary circulation and liberated with the exhaled air.

Many cases are rebellious to treatment, and naturally it is more difficult to control intestinal than gastric digestion, not only because the intestine is relatively inaccessible, but because of the highly complex digestive processes in which the bile, pancreatic and intestinal juices are concerned.

The dietetic treatment of autointoxication is suggested by a knowledge of its aetiology. The fermentation cases do best upon a diet of simple proteid foods, broths, fish, chicken, eggs, scraped beef, etc., with dry toast, stale bread or crackers. The putrefactive cases, if severe, may be best treated with a diet of bread and milk, later with fruits, cereals, and the fresh green vegetables. In both classes of cases elimination should first be promoted by laxatives, such as calomel or castor oil, and the drinking of water in large quantity; in both, intestinal antifermentative remedies are useful, such as creosote, ß-naphthol, salol, ichthyol, or bismuth subgallate.

Those mixed cases in which the symptoms of fermentation and putrefaction are combined, are best treated with a temporary diet of milk and bread or crackers, together with eliminatives and anti-fermentatives, as above described.