Intestinal Flora and Oxalate Excretion in Patients with Enteric Hyperoxaluria

Abstract

The commonest type of hyperoxaluria today is found in conditions of gastrointestinal malabsorption and is designated “enteric hyperoxaluria”. It is most pronounced after intestinal resection1 and jejunoileal bypass2. Increased absorption of oxalate is the main reason for the hyperoxaluria3. Most of the absorption takes place in the colon4, but the reason for it is not fully known. Little is known about the role of the intestinal flora in patients with enteric hyperoxaluria. Changes in the intestinal flora might theoretically influence the hyperoxaluria. After jejuno-ileal bypass the bacterial flora in the small intestine changes towards that in the large intestine5. This might result in deconjugation of bile acids and steatorrhea, since conjugated bile acids are important stimulators of fat absorption. Another possibility is that in these patients bacteria produce fatty acids and oxalate in the colon, since the amount of nutrients available for bacterial metabolism in the colon is increased in patients with malabsorption.