INFLUENCE OF INTESTINAL INFLAMMATION (IBD) AND SMALL AND LARGE-BOWEL LENGTH ON FECAL SHORT-CHAIN FATTY-ACIDS AND LACTATE

Treatment with short-chain fatty acids (SCFAs) seems promising in ulce rative colitis and changes in colonocyte oxidation of butyrate have be en suggested to be of importance for the development of this disease. The influence of small and large bowel length after surgery on SCFAs i s only partly known. SCFAs and lactate were measured in consecutive fe cal samples from 300 patients with ulcerative colitis (103), Crohn's d isease (127), and noninflammatory bowel disease (70); 205 had had surg ery, 52 had short bowels (<200 cm). Lactate (mainly the L-isomer) was elevated in ulcerative colitis patients with pancolitis (mean +/- SEM, 17 +/- 5 mmol/liter) and proctitis (12 +/- 3 mmol/liter) compared wit h quiescent ulcerative colitis (3 +/- 1 mmol/liter, P < 0.01), and cor related with the index of Truelove (R = 0.52, P < 0.0005). Lactate was also increased in Crohn's colitis (21 +/- 8 mmol/liter), but not in i solated ileitis (4 +/- 2 mmol/liter), compared with quiescent Crohn's disease (7 +/- 2 mmol/liter, P < 0.02), but did not correlate with the activity index (CDAI; R = 0.18, P = 0.12). In contrast to earlier rep orts, SCFAs (including butyrate) did not correlate with inflammatory a ctivity or localization in either ulcerative colitis or Crohn's diseas e. The length of the small bowel had no influence on SCFAs and lactate in patients with either no colonic function (ileostomies), or with >5 0% and <50% preserved colorectal length, respectively. Fecal SCFAs fro m completely (100%) preserved large bowels (89 +/- 5 mmol/liter), and from >50% (76 +/- 7 mmol/liter) and <50% (72 +/- 7 mmol/liter) preserv ed colons were not significantly different, in contrast to SCFAs from ileorectals (51 +/- 10 mmol/iiter), ileal reservoirs (57 +/- 6 mmol/li ter), and ileostomies (20 +/- 2 mmol/liter). Fecal lactate is associat ed with proctocolitis, but not with ileitis. SCFAs were remarkably con stant and not influenced by active inflammation in patients with infla mmatory bowel disease or extreme differences in the length of the smal l or large intestine.