To resume, this condition of intestinal indigestion may arise from a variety of causes: excess or deficiency of gastric juice, defective motility, and diminished secretion of intestinal juices, and in all cases improper food may determine such intestinal derangement.
The clinical features presented are very variable. It is often difficult, if not impossible, on the basis purely of the subjective symptoms, to decide in any given instance how far the symptoms are referable to intestinal stasis, or to a chronic infection, with a resultant catarrhal state of the mucosa, or to both causes combined in varying proportions.
But, be the explanation what it may, in our experience the most common antecedent or concomitant of gout is intestinal dyspepsia. Its secondary consequences are far reaching, especially if the small bowel be involved, catarrh of which may lead to reduction in the secretion of bile and pancreatic juice.
How commonly in these cases do we meet with symptoms indicative of sluggishness of the hepatic functions, such as turbidity of the urine, a pale or abnormally dark colour of the alvine evacuations. Also, whatever be its true etiology, they exhibit not so uncommonly sugar in the urine, the so-called “gouty” glycosuria.
Now, as a mere glance will show, diminution and impairment of the biliary and pancreatic secretions have far-reaching consequences. Foodstuffs undergo abnormal changes, are less easily absorbed, and simultaneously chemical products are formed which irritate the intestinal mucosa. Nor do the baneful effects cease here, for, owing to the unusual nature and reaction of the intestinal content, the bacterial flora in the bowel undergo modifications.
Thus, organisms normally present only in small numbers in the small intestine find the altered medium more suitable for their growth and multiplication; while others, whose usual habitat is the large bowel, migrate upwards, and infect the ileum and duodenum, and ultimately the biliary and pancreatic passages.
In the presence of such deficiency in the intestinal juices, proteins are imperfectly digested, and putrefaction under microbic action favoured. At the same time the digestion of carbohydrates is impaired, organic acids are formed, and gases in larger amounts liberated. Ultimately, owing to absorption of these irritating products, a condition of chronic toxæmia results.
Summary
It now devolves upon us to decide whether the phenomena of gout are best explicable as the outcome of auto-intoxication, or of infection or sub-infection. The uric acid theory was in truth one of auto-toxæmia, the varied manifestations of gout being attributed to mechanical or toxic irritation by uric acid, the end-product of purin metabolism. But, as we hope to have shown conclusively, uric acid is not toxic, and per se is apparently as innocuous as those other and intermediary products of metabolism which give rise to cystinuria and alkaptonuria.