Polymeric Diet Research Articles

Absorption of Nutrients Is Only Slightly Reduced by Supplementing Enteral Formulas with Viscous Fiber in Miniature Pigs

Viscous polysaccharides reduce intestinal absorption of glucose and diminish postprandial hyperglycemia. However, it is unknown whether viscous fiber also inhibits absorption of nutrients under conditions of enteric feeding. Therefore, we measured the absorption rates of nutrients in miniature pigs by perfusing a 150-cm length of jejunum with 8.37 kJ/min of the three following enteral diets: an isoosmotic oligomeric diet (1670 kJ/L), a hyperosmotic oligomeric diet and an isoosmotic polymeric diet (both 3350 kJ/L). The diets were supplemented with guar gum from 0 to 4.4 g/L. With the three guar-free diets, the mean absorption rate of energy was 5.2 ± 0.32 kJ/min, corresponding to 62% of the energy infused. Absorption rates of carbohydrate, protein, fat and energy linearly declined as concentrations of guar or the logarithm of chyme viscosity increased. Due to modulations in viscosity, the inhibitory effects of guar were significantly different among the three diets. With the isoosmotic and hyperosmotic oligomeric and the polymeric diets, the addition of 1 g guar/L diminished the absorption of energy by 9.7, 6.6 and 3.7%, respectively. The strong inhibitory effect on nutrient absorption with the isoosmotic oligomeric diet was caused by an increase in chyme viscosity due to water absorption. With the hyperosmotic oligomeric and the polymeric diets, the chyme viscosity and thus inhibitory effects on absorption were diminished by water secretion and the concomitant infusion of pancreatic enzymes. Results indicate that the addition of small amounts of guar gum to enteral diets of high energy density exerts only small effects on absorption of nutrients.

Effect of intragastric or intraduodenal administration of a polymeric diet on gallbladder motility, small-bowel transit time, and hormone release

Objective: During postpyloric tube feeding, GI intolerance is observed more frequently than during prepyloric feeding, possibly by evoking a stronger GI response. Methods: We investigated the effect of intragastric and intraduodenal administration of a polymeric diet (125 kcal/h) on gallbladder motility (by ultrasonography), duodeno-cecal transit time (by lactulose H 2 breath test), and GI hormone release (including cholecystokinin, pancreatic polypeptide, and gastrin). Six healthy subjects (two male, four female; mean age 22 yr, range 18–27 yr) were studied on two separate occasions in random order during 6 h of continuous administration of the diet through either the gastric or duodenal port of a two-lumen tube. Results: Intraduodenal feeding resulted in a more rapid contraction of the gallbladder, from 32 ± 4 to 23 ± 4 cm 3 at 10 min ( p < 0.05), reaching a minimum of 6 ± 1 cm 3, in contrast to intragastric feeding (31 ± 4 to 19 ± 3 cm 3 at 60 min, p < 0.05; minimum 14 ± 1 cm 3). The gallbladder remained contracted during the 6-h study period during both intraduodenal and intragastric feeding. Small-bowel transit time was significantly accelerated during intraduodenal compared with intragastric feeding (51 ± 12 vs 81 ± 9 min; p = 0.003). Plasma cholecystokinin secretion was significantly ( p < 0.05) increased during intraduodenal compared with intragastric feeding (848 ± 107 vs 279 ± 89 pmol · L −1 · 360 min). The same was true for pancreatic polypeptide secretion. However, gastrin release was significantly ( p < 0.05) higher during intragastric feeding. Conclusions: Intraduodenal feeding elicited a stronger GI response than intragastric feeding, as demonstrated by accelerated small-bowel transit time, more rapid and stronger gallbladder contractions, and increased cholecystokinin and pancreatic polypeptide release. Gastrin release, on the other hand, was stronger during intragastric feeding.

Gastrointestinal motility and gastric tube feeding in mechanically ventilated patients.

To determine the fasted and fed gastrointestinal motility characteristics that are possibly responsible for gastric retention in mechanically ventilated patients. Prospective, case series. Surgical intensive care unit of a university hospital. Seven patients who required mechanical ventilation for thoracic or combined thoracic-neurologic injuries and nine healthy volunteers. None. Antroduodenal manometry was performed during fasting and gastric feeding with a polymeric diet in patients during mechanical ventilation, weaning, and after detubation. Gastric retention volumes were determined during gastric tube feeding. Motility data were compared with recordings from nine healthy volunteers. During the fasting state, under sedation and morphine, the migrating motor complex in patients was significantly (p < .001) shortened: median 32.0 vs. 101.0 mins in healthy volunteers. During gastric tube feeding, the motility pattern did not convert to a normal postprandial pattern until morphine was discontinued. An interdigestive or mixed interdigestive-postprandial pattern was seen during gastric tube feeding in most patients during morphine administration. Most (94%) of the activity fronts during gastric feeding started in the duodenum. Gastric retention percentages during gastric tube feeding were negatively correlated (r2=.44; p < .01) with antral motor activity. These data suggest that morphine administration affects antroduodenal motility in mechanically ventilated patients. The gastrointestinal motor pattern involved in impaired gastric emptying in morphine-treated patients is characterized by antral hypomotility and persisting duodenal activity fronts during continuous intragastric feeding. The observed motility patterns suggest that early administration of enteral feeding might be more effective into the duodenum or jejunum than into the stomach of mechanically ventilated patients.

Enteral feeding techniques.

Major technical advances in enteral nutrition include the use of erythromycin or magnetic guidance for the placement of the feeding tube into the duodenum, the development of new enteral tubes, and bedside methods to control the tube position. Percutaneous endoscopic jejunostomy is becoming a safe procedure with a high success rate. Specialized diets offer little or no clinical advantages when compared with standard polymeric diets.

Intestinal absorption of nutrients is not influenced by soy fiber and does not differ between oligomeric and polymeric enteral diets.

Enteric feeding is often associated with diarrhea. To avoid this side effect, isoosmotic and fiber-supplemented enteral diets are recommended. The aims of this study were to determine whether supplementing enteral diets with soy fiber influences nutrient absorption and whether in enteric feeding absorption of nutrients and water fluxes differ between hyperosmotic oligomeric and isoosmotic polymeric diets. In mini pigs intestinal absorption and water fluxes were measured by perfusing a 150-cm length of jejunum. Six noncommercial iso- and hyperosmotic oligomeric and polymeric diets and six commercial polymeric diets, either fiber-free or supplemented with soy fiber, were used. Pancreatic enzymes were infused concomitantly with the polymeric diets. The absorption of nutrients and energy did not differ between oligomeric and polymeric diets. Oligomeric diets of high energy density produced a pronounced secretion of water. Despite lower initial osmolality, polymeric diets produced a similar secretion of water due to rapid pancreatic hydrolysis. Supplementing diets with largely insoluble soy fiber increased viscosity only between 4.6 and 14.5 mPa x sec. Soy fiber did not influence absorption of nutrients and energy and had also no effects on luminal transit and flow rate. The lack of effects was not due to dilution of chyme by intestinal secretion of water because no differences existed between isoosmotic and hyperosmotic oligomeric diets. In conclusion, supplementing enteral diets with soy fiber does not impair the absorption of nutrients. Enteric feeding with isoosmotic polymeric diets provides no advantage compared with hyperosmotic oligomeric diets with respect to absorption of nutrients and secretion of water.

A randomized controlled study of total parenteral nutrition and enteral nutrition by elemental and polymeric diet as primary therapy in active phase of Crohn's disease

A randomized controlled study of total parenteral nutrition and enteral nutrition by elemental and polymeric diet as primary therapy in active phase of Crohn's disease

The use of polymeric liquid enteral diets for nutritional support in seriously ill or injured small animals: clinical results in 200 patients.

This prospective, multicenter study evaluated the use of four polymeric liquid enteral (PLE) diets manufactured for dogs and cats in 200 ill or injured patients. Polymeric liquid enteral diets were administered by free-choice feeding, syringe, or feeding tube for up to 208 days. Overall results indicated a 4.9% incidence of vomiting in dogs and a 7.9% incidence in cats; an 8.9% incidence of diarrhea in dogs and an 18.4% incidence in cats. Patients fed the PLE diets seven days or longer had an average increase in body weight of 1.4% in dogs, an average decrease in body weight of 3.8% in cats, increases in lymphocyte counts, and mild decreases in serum albumin.

RESOLUTION OF MUCOSAL INFLAMMATION AND FALL IN IL-1 BETA mRNA IN ACTIVE CROHN'S DISEASE IN RESPONSE TO POLYMERIC DIET CT3211.

Enteral nutrition (EN) is an established therapy in the treatment of active Crohn's disease (CD), although the mechanism of its action is uncertain. 15 children (10.4-16.3 years) with active CD (8 newly diagnosed, 7 in relapse) were treated exclusively with a new oral polymeric diet (containing whole casein as the protein source), for 8 weeks. Before and after treatment, subjects were assessed clinically (modified Lloyd Still index), biochemically (CRP), endoscopically, histologically and for IL-1 beta mRNA (8/15 cases) in ileal, caecal and colonic biopsies by quantitative RT-PCR. All newly diagnosed, and 5/7 relapsed cases responded to EN (complete remission in 9/15). The 2 treatment failures had severe colonic disease and an appendiceal abscess. CRP declined with treatment (from median 20 to 1.0 mg/l, p<0.0001). Endoscopic appearance scored from 0 (normal) to 3 (severe disease) improved in the terminal ileum (TI) (from median 2.0 to 0.5, p<0.05), but not significantly in colon (unchanged at median score 1.0). Histology scored from 0 (normal) to 3 (severe inflammation with ulceration) improved significantly in TI (from median 1.5 to 0.5, p<0.05) but not in the colon (2.0 to 1.0, p=0.07). There was a decrease in IL-1 beta mRNA at all sites biopsied (caecum and colon: median 1.36 ×105 to 2.55 ×104, and 8.65 ×104 to 9.5 ×103 transcripts mRNA/ug RNA), which in the TI achieved significance (decline from median 5.53 ×106 to 5 ×103 transcripts mRNA/ug RNA; p<0.01). In active CD the clinical response to polymeric diet CT3211 is associated with mucosal healing, and a fall in mucosal mRNA of the pro-inflammatory cytokine IL-1 beta.

Does percutaneous endoscopic gastrostomy prevent gastro-oesophageal reflux during the enteral feeding of elderly patients?

Percutaneous endoscopic gastrostomy (PEG) is reported to be a safe method for enteral feeding, although its ability to prevent gastro-oesophageal reflux (GOR) during enteral feeding remains controversial. In 12 elderly patients fed enterally to avoid the risk of tracheal aspiration, we have compared two 24-h oesophageal pH profiles, one recorded when enteral feeding was delivered at first via a nasogastric tube (NGT), and the other via a PEG. The second recording was always performed at least 8 days after gastrostomy placement. Enteral nutrition consisted of 500 ml of a polymeric diet delivered 3 times a day at 08:00, 13:00 and 18:00. After gastrostomy placement, enteral feeding was associated with a pathological acid reflux in 8 out of 12 patients. In all of these 8 patients, GOR was mostly related to a high number of reflux episodes. In 4 out of 8 patients, GOR occurred only during the 3 h following the administration of the nutritive diet. In 4 of the patients, GOR did not occur any more after removal of the NGT, whilst gastrostomy placement was followed by GOR in 5 patients. GOR during enteral feeding via PEG is common in elderly subjects. We have shown that a chronological relationship existed in some patients between the endoscopic procedure and the onset of a pathological GOR.

Insulin-like Growth Factor-I (IGF-I) and Glutamine Improve Structure and Function in the Small Bowel Allograft

IGF-I, a mitogenic polypeptide hormone, and glutamine (GLN), the preferred enterocyte fuel, singularly improve growth and structure of the small bowel isograft; however, their combined effects on intestinal allografts are unknown. This study examined the effects of IGF-I and GLN, singularly and in combination, on the structure and function of the intestinal allograft. Fifty-nine adult rats underwent resection of the distal 60% of small bowel and received either a 40-cm isograft or an allograft. Either IGF-I (2.4 mg/kg/day) or its vehicle was infused continuously by subcutaneous minipumps. An isocaloric polymeric diet with either 2% GLN or isonitrogenously balanced 2% nonessential amino acids was given continuously by gastrostomy for 10 days. Five groups were studied: isograft (ISO) alone, allograft (ALLO) alone, ALLO and GLN, ALLO and IGF-I, and ALLO and IGF-I with GLN. All recipients received Cyclosporine A (15 mg/kg, im) daily. Mucosal villus height, surface area. crypt depth, IgA, IgG, IgM, and intercellular adhesion molecule-1 (ICAM-I) plasma cells in intestinal tissue, glucose and water absorption of intestinal graft, bacterial translocation (BT) to mesenteric lymph nodes. and body weight were determined. IGF-I increased villus height, surface area ( P < 0.001), crypt depth ( P < 0.01), and glucose absorption ( P < 0.05) compared to the ISO and ALLO groups. GLN increased only crypt depth when compared to the ALLO group ( P < 0.01). Both IGF-I and GLN independently decreased BT to MLN ( P < 0.05) and, in combination, enhanced water absorption ( P < 0.05). There were no significant differences in the number of monoclonal antibody IgA, IgG, and ICAM-1 plasma cells among groups. IgM plasma cells were increased in the IGF-I group compared to the ALLO alone ( P < 0.05). IGF-I and GLN improve function and structure of the small bowel allograft in the rat.

Insulin-like growth factor-I improves mucosal structure and function in transplanted rat small intestine.

The transplanted small intestine develops significant mucosal atrophy, impaired nutrient and water absorption, and increased bacterial translocation to mesenteric lymph nodes in rats maintained on elemental diets or total parenteral nutrition. This study determined the effects of administration of an peptide growth factor (insulin-like growth factor-I[IGF-I]) on the mucosal structure and barrier function of rat small bowel isografts. Thirty-six adult Lewis rats underwent either resection of the distal 60% of the small bowel and proximal colon followed by a 40-cm orthotopic jejunal isograft or proximal small bowel transection and distal small bowel resection to leave an analogous length of small intestine in control animals. All rats received an isocaloric, isonitrogenous, polymeric diet (200 kcal/kg/day, 2 gN/kg/day) by gastrostomy and were infused with either IGF-I (2.4 mg/kg/day) or vehicle by osmotic pumps subcutaneously. After 10 days of treatment, jejunal crypt cell production, mucosal morphometric indices, glucose and water absorption, body weight, and bacterial translocation to mesenteric lymph nodes (MLN) were measured. Jejunal mRNA content for IGF-I, IGF-I receptor, and IGF-binding proteins 3 and 4 (IGFBP-3,4) were determined by Northern blotting. Crypt cell production, villus height, crypt depth, and villus surface area were significantly increased in control and transplanted jejunum of rats infused with IGF-I when compared to animals given vehicle alone. Additionally, jejunal glucose absorption and water absorption were significantly improved in both IGF-I groups when compared with their respective vehicle controls. IGF-I infusion increased body weight in transplanted and control animals and markedly reduced bacterial translocation to MLN after small bowel transplantation. Jejunal levels of IGF-I mRNA were significantly increased in transplanted animals when compared to transected controls. IGF-I treatment significantly increased IGFBP-3 tissue mRNA levels in both transected and transplanted animals. These results demonstrate that IGF-I administration, after small bowel transplantation, improves mucosal structure and absorptive function and reduces bacterial translocation to MLN. IGF-I may have important effects in transplanted small bowel both as an endogenous and administered growth factor.

Nutrition entérale pré et postopératoire en chirurgie réglée de l'adulte. Techniques, avantages et inconvénients

This review examined the techniques for enteral nutrition (routes and methods of administration and choice of enteral diets) in the perioperative period of elective surgery in adults. Only few controlled studies have assessed the efficiency of techniques according to the indication of enteral feeding (pre or postoperative period, digestive or non-digestive surgery). The nasogastric tube remains the most appropriate method to deliver short-term enteral feeding during the preoperative period. Today percutaneous endoscopic gastrostomy is the preferred method of gastrostomy. It is indicated in long term enteral nutrition, for example in the perioperative period of cancer surgery of head and neck. In the postoperative period of digestive surgery, intrajejunal feeding is usually delivered by a surgical jejunostomy or by a nasojejunal tube. Controlled studies comparing these two methods are still lacking. An important limitation of intrajejunal feeding is the poor tolerance of enteral diet during the first postoperative days after major upper abdominal surgery. The choice of enteral diet in the perioperative period remains contreversial. There is no clinical evidence to support the hypothesis that the use of pre-digested diets in jejunostomy feeding has a better nutritional benefit and a better tolerance than polymeric diets. Small peptides offer some metabolic advantages, however the clinical superiority of these nutrients over polymeric diets is not definitively proven. Continuous administration of enteral nutrition is usually required in case of jejunal feeding. In the other cases, some data suggest that enteral nutrition is more efficient using an intermittent feeding regimen.

Nutrition entérale pré et postopératoire en chirurgie réglée de l'adulte. Techniques, avantages et inconvénients

This review examined the techniques for enteral nutrition (routes and methods of administration and choice of enteral diets) in the perioperative period of elective surgery in adults. Only few controlled studies have assessed the efficiency of techniques according to the indication of enteral feeding (pre or postoperative period, digestive or non-digestive surgery). The nasogastric tube remains the most appropriate method to deliver short-term enteral feeding during the preoperative period. Today percutaneous endoscopic gastrostomy is the preferred method of gastrostomy. It is indicated in long term enteral nutrition, for example in the perioperative period of cancer surgery of head and neck. In the postoperative period of digestive surgery, intrajejunal feeding is usually delivered by a surgical jejunostomy or by a nasojejunal tube. Controlled studies comparing these two methods are still lacking. An important limitation of intrajejunal feeding is the poor tolerance of enteral diet during the first postoperative days after major upper abdominal surgery. The choice of enteral diet in the perioperative period remains contreversial. There is no clinical evidence to support the hypothesis that the use of pre-digested diets in jejunostomy feeding has a better nutritional benefit and a better tolerance than polymeric diets. Small peptides offer some metabolic advantages, however the clinical superiority of these nutrients over polymeric diets is not definitively proven. Continuous administration of enteral nutrition is usually required in case of jejunal feeding. In the other cases, some data suggest that enteral nutrition is more efficient using an intermittent feeding regimen.

Polymeric nutrition as the primary therapy in children with small bowel Crohn's disease.

Recent studies in adults have shown that polymeric (whole protein) diets are as effective as semi-elemental and elemental formulae for the induction of remission in small bowel Crohn's disease. Whole protein diets are more palatable and cheaper. There have been no studies confirming efficacy in children. We report our experience with seven children with active small bowel Crohn's disease given a casein-based, polymeric feed rich in TGF-beta 2 (Specific Polymeric Diet; Nestle-Clintec; Vevey, Switzerland) as complete nutrition for 8 weeks. Initial and follow-up assessments were performed. All children showed a significant improvement in disease activity, with C-reactive protein returning to normal, an increase in serum albumin and a good weight gain. Initial and follow-up ileal biopsies were assessed and showed reduced mucosal inflammation in six of seven children, with complete healing in two. In an uncontrolled descriptive study we have shown that a polymeric (whole protein) diet is a therapeutic option for small bowel Crohn's disease in children. By comprehensive follow-up we have demonstrated clinical and biochemical remission, with an improved endoscopic appearance and a reduction of mucosal inflammation in the terminal ileum.

Colonic secretory effect in response to enteral feeding in humans.

Diarrhoea complicating enteral feeding is a common clinical problem affecting up to 25% of patients. Its pathogenesis remains unknown. A new technique of human in vivo segmental colonic perfusion was used to investigate colonic water and electrolyte movement in response to enteral feeding. Four groups of studies were performed in which low and high load polymeric enteral diet infusions were undertaken, either intragastrically or intraduodenally (n = 6 each group). Net absorption of sodium, chloride, and water occurred during fasting throughout the colon in all groups. There was a significant net secretion of sodium, chloride, and water in the ascending colon during low load (sodium: -42 mmol/h; 95% confidence limits -52 to -19, Chloride: -18 mmol/h; -50 to +16, water: -174 ml/h; -348 to -30) and high load (sodium: -24 mmol/h; -60 to +8, chloride: -18 mmol/h; -31 to +16, water: -120 ml/h; -246 to +6) gastric feeding, and during high load duodenal feeding (sodium: -12 mmol/h; -22 to -6, chloride; -6 mmol/h; -16 to +3, water: -72 ml/h; -144 to -6). Net secretion persisted in the distal colon only during high load gastric feeding. In the other three groups there was a net absorption in the distal colon. This study identified a significant colonic secretory response to enteral feeding, which is related to the site and load of the diet infusion. This response may play an important part in the pathogenesis of enteral feeding related diarrhoea.

Duodenal motor response to continuous enteral feeding is impaired in mechanically ventilated critically ill patients

In order to investigate the duodenal motor response to continuous enteral feeding during critical illness, we recorded the duodenal contractions of 12 mechanically ventilated critically ill patients during a 4 h fasting period immediately followed by another 4 h period of continuous (100 kcal/h) nasogastric feeding with a polymeric diet. Duodenal motility was recorded by manometry (perfused catheter technique) and the migrating motor complexes (MMC) were identified by their activity front (period of high frequency, regular contractions). The incidence and the mean duration of activity fronts as well as the mean duration of the MMC (time interval separating two successive activity fronts) recorded during both periods were compared. The incidence of activity fronts (fasting: median: 2.5, interquartile range: 5.5; feeding: median: 2, interquartile range: 3.5), their duration (fasting: 6.2 ± 1.6 min; feeding: 5.8 ± 1.6 min), and the mean duration of the MMC (fasting: 50.9 ± 24.7 min; feeding: 49.1 ± 20.3 min) were similar during both periods. We conclude that in these patients, the fasting pattern of motility is not interrupted by the continuous nasogastric administration of a polymeric diet. Since the activity fronts of the MMCs are highly propulsive, we suggest that their abnormal persistence during feeding may play a role in the pathophysiology of unexplained diarrhoea in some critically ill patients.

Surgical and nutritional treatment of inflammatory bowel disease

Patients with ulcerative colitis who undergo an Meal-anal pouch operation without ileostomy have increased morbidity. The quality of life after ileal-anal pouch procedure is comparable to patients with ulcerative colitis treated medically. The number of anastomoses is an important prognostic indicator for early symptomatic recurrence after Crohn's disease. Diversion of the fecal stream for patients with Crohn's disease of the colon produces a high incidence of sustained idsease remission, but the prospect of future restoration of intestinal continuity is limited. The energy requirements for patients with active Crohn's disease is similar (30 to 35 kcal/kg body weight/d) to other hospitalized patients. Polymeric diets are as effective as steroids in inducing short-term remission in patients with active Crohn's disease. Food sensitivities in patients with Crohn's disease are of insufficient importance to warrant routine trials of elimination diets.

Enteral nutrition as primary therapy in Crohn's disease.

The developments in enteral feeding for Crohn's disease in the past decade are critically reviewed. The advent of amino acid based chemically defined elemental diets signalled the end of 'total bowel rest' in the management of these patients. Subsequently, controlled clinical trials showed that elemental diets were as effective as corticosteroids in inducing clinical remission in patients with acute exacerbations of Crohn's disease. The later use of peptide based elemental diets, in Crohn's disease produced somewhat conflicting results. The initial uncontrolled studies suggest that polymeric whole protein diets might also be effective in the management of acute exacerbations of the disease, casting in turn doubts concerning the role of dietary antigens in the pathogenesis of Crohn's disease. Results of controlled studies comparing the use of elemental and polymeric diets as primary therapy in Crohn's disease have, however, also produced conflicting results. The results of one recent controlled trial in which the use of polymeric diet was compared with that of corticosteroids does, however, suggest that these diets may have a primary therapeutic effect in Crohn's disease. An analysis of the composition of some of the enteral diets used in different trials suggest that the effectiveness of enteral diets in treating active Crohn's disease might relate more to their fat than nitrogen composition. A hypothesis is proposed that the effectiveness of enteral nutrition in the primary therapy of acute exacerbations of Crohn's disease occurs because the successful diets used contain insufficient precursors for arachidonate derived eicosanoid synthesis.

Soy fiber delays disease onset and prolongs survival in experimental Clostridium difficile ileocecitis.

Clostridium difficile colitis is a disabling complication in critically ill patients who commonly receive broad-spectrum antibiotics and liquid diets. To date, there is no experimental model specifically designed to investigate the effects of liquid diets on this type of colitis. The addition of fiber to liquid diets normalizes gut structure and improves absorptive function in selected conditions of intestinal dysfunction. The purposes of this study were the following: (1) to develop a reproducible model to examine the interaction of acute C difficile-induced colitis and liquid diets, (2) to determine whether the addition of soy fiber to a liquid diet improves disease, and (3) to investigate possible mechanisms of fiber-mediated disease improvement. Syrian hamsters were pair-fed with either a polymeric liquid diet or the same diet with 1.4% soy fiber for 10 days. Animals were given either clindamycin and C difficile (to produce ileocecitis), or equivalent volumes of saline. Mean survival time and systematic stool examinations for C difficile toxin positivity, liquidity, and percent water were performed to determine the effect of soy fiber on disease. Survival time was prolonged by 34% (p < .05), and C difficile toxin positivity and stool liquidity were significantly reduced (p < .05) with fiber. Additional animals were studied to determine possible mechanisms for improved survival in fiber-supplemented animals. Cecal histology, colonic water absorption, cecal microflora, and gastric to anus transit time were measured in these animals. Colonic water absorption and gastric to anus transit time were significantly increased (p < .05) and decreased (p < .05) with fiber, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum interleukin-8 in inflammatory bowel disease.

To investigate the relationship between serum concentrations of interleukin-8 (IL-8) and disease activity in inflammatory bowel disease, serum IL-8 concentrations were measured by enzyme-linked immunosorbent assay (ELISA) in 93 patients. Interleukin-8 levels were compared with plasma interleukin-6 (IL-6) levels in 80 of these patients. Interleukin-8 levels were also measured in ten patients with active Crohn's disease, before and after treatment with a defined formula polymeric diet. Of these patients, 70 out of 93 IL-8 concentrations were below the detection limit of the assay. Levels were higher in patients with active ulcerative colitis (median < 20 pg/mL, 75th centile value = 190) compared with inactive disease (median and 75th centile value < 20; P < 0.05). Interleukin-8 concentrations correlated with a combined score for disease severity and extent (P = 0.01). Thirty-eight per cent (8/20) of patients with active Crohn's disease also had high levels of IL-8 but there was no significant difference between active and inactive disease. There was no correlation between serum IL-8 and plasma IL-6; on the contrary, very few patients had raised blood levels of both cytokines. In the diet treated group, serum IL-8 fell significantly after treatment (median = 37 pg/mL, range < 20-4615 before treatment, median < 20, range < 20-104 after treatment; P = 0.03). The results suggest that although IL-8 may be involved in the inflammatory process in inflammatory bowel disease, it is a poor marker of disease activity.