Pouchitis: result of microbial imbalance?

Probiotics and prebiotics: role in clinical disease states

Parents of pediatric patients are seeking alternatives to conventional therapy in the prevention and treatment of gastrointestinal disease states because of therapeutic failures caused by the increased incidence of antibiotic resistance. One such alternative is the use of probiotics and prebiotics to stimulate health-promoting indigenous flora to affect pathogen colonization and expression of disease. Probiotics are live flora given in oral quantities that allow for colonization of the colon. Probiotics are given as functional foods or dietary supplements, and function to activate the mucosal immune system and prevent pathogen colonization and translocation by strengthening the mucosal barrier, interfering with pathogen colonization, and in some instances, producing secretory antibacterial substances. Prebiotics are nondigestible carbohydrates, principally oligosoccharides, that are fermented by colonic commensals, stimulating their proliferation and producing short-chain fatty acids. Both protective nutrients have been shown to reduce the incidence and severity of infantile diarrhea, particularly rotaviral gastroenteritis, prevent antibiotic-induced diarrhea, and prevent and treat intestinal food allergy. With additional multicenter clinical trial confirmations, these substances may become routine in the care of infants and young children.

Assessment of mucosal inflammation and blood flow in response to four weeks' intervention with probiotics in patients operated with a J-configurated ileal-pouch-anal-anastomosis (IPAA)

BACKGROUND

Pouchitis is a common and troublesome condition in patients operated on with ileal-pouch-anal-anastomosis (IPAA). A disturbed mucosal perfusion in the pouch has been suggested as a possible cause. Laser Doppler flowmetry (LDF) has been used successfully to measure gastric and colonic mucosal perfusion in humans. In a previous study, we demonstrated a reduced mucosal perfusion in the distal part of the pouch, during probiotic intervention, examined by LDF measurement. The aim of the present study was to confirm our previous results in a much larger material, and to compare the results of LDF measurements and inflammatory activity in ulcerative colitis (UC) patients with those in familial adenomatous polyposis (FAP) patients.

METHODS

Five hundred millilitres of a fermented milk product (Cultura), containing live lactobacilli (La-5) and bifidobacteria (Bb-12), was given daily for 4 weeks to 41 UC and 10 patients with FAP, operated on with IPAA. Mucosal perfusion was measured with LDF and the degree of inflammation was examined at predefined levels of the distal bowel by histology and faecal calprotectin measurements both before and after intervention. We also evaluated the applicability of a Pouchitis Disease Activity Index (PDAI).

RESULTS

The LDF measurements were reproducible in the pelvic pouch at each of the predefined levels, but did not change during intervention. Mucosal perfusion was significantly reduced in the distal compared to the proximal part of the pouch in the UC group (P < 0.05). The perfusion levels were higher in the FAP patients compared to the UC patientsat all predefined levels (P < 0.05). Calprotectin levels and histological score did not change significantlyafter intervention in any of the groups. The calprotectin level was significantly lower in the FAP compared to the UC group both before and after intervention. The PDAI decreased in both groups from alevel considered diagnostic for pouchitis to a level considered as not active pouchitis. The decreasewas significant for the UC patients.

CONCLUSIONS

The results did not demonstrate an effect of probiotics on histology, although a significant effect on the PDAI was achieved, which concurs with the previously reported effect on symptoms and endoscopic score. The significantly reduced blood flow in the UC group compared to the FAP group, operated on with the same procedure, and the significantly increased calprotectin levels in the UC group, are original findings. Both findings may be related to an increased risk for pouchitis among UC patients. The lack of effect of intervention on mucosal perfusion does not exclude a role for reduced circulation as a cause of pouchitis based on the reduced LDF measurements in the distal part of the pouch.

Randomized placebo-controlled trial assessing the effect of bifidobacteria-fermented milk on active ulcerative colitis

BACKGROUND

Probiotics are efficacious for treating and maintaining remission of ulcerative colitis.

AIM

To conduct a randomized placebo-controlled trial of bifidobacteria-fermented milk supplementation as a dietary adjunct in treating active ulcerative colitis.

METHODS

Twenty patients with mild to moderate, active, ulcerative colitis randomly received 100 mL/day of bifidobacteria-fermented milk or placebo for 12 weeks with conventional treatment.

RESULTS

Clinical and endoscopic activity indices and histological scores were similar in the two groups before treatment. Although improvements were significant in both groups, the clinical activity index was significantly lower in the bifidobacteria-fermented milk than in the placebo group after treatment. The post-treatment endoscopic activity index and histological score were significantly reduced in the bifidobacteria-fermented milk, but not the placebo group. Increases in faecal butyrate, propionate and short-chain fatty acid concentrations were significant in the bifidobacteria-fermented milk, but not the placebo group. No adverse effects were observed in either group.

CONCLUSION

Supplementation with this bifidobacteria-fermented milk product is safe and more effective than conventional treatment alone, suggesting possible beneficial effects in managing active ulcerative colitis. This is a pilot study and further larger studies are required to confirm the result these preliminary results.

Host-bacterial interactions in inflammatory bowel disease

Large numbers of different bacterial species are resident in the lumen of the distal gastrointestinal tract. The normal intestinal host-microbial interactions are not well understood, but the relationship is generally believed to be either mutually beneficial or beneficial to one without disadvantage to the other. Animal model and clinical studies suggest that IBD (inflammatory bowel disease) may develop in a susceptible individual when the normal host-bacterial relationship is dysregulated. In addition to rodent models, this article reviews studies that have investigated the cellular and molecular mechanisms of interactions between intestinal mucosal cells and the resident luminal bacteria in healthy individuals and patients with ulcerative colitis and Crohn's disease. Mechanisms by which the intestinal mucosa is able to avoid pro-inflammatory responses to commensal bacteria (and their products) but able to respond appropriately to luminal pathogens is currently an area of active investigation. Such studies are beginning to provide important clues regarding possible alterations in the mucosa that lead to the development of pro-inflammatory responses to resident bacteria in patients with IBD. Approaches to alter the intestinal microflora for therapeutic purposes and their potential mechanisms of action are also discussed.

Histologic predictors of pouchitis in patients with chronic ulcerative colitis

Inflammation of ileal reservoir mucosa ("pouchitis") is a common sequelae in ulcerative colitis (UC) patients who have had a colectomy with ileal pouch anal-anastomosis (IPAA). Although several clinical, genetic, and laboratory parameters have been evaluated, reliable pathologic predictors for the development of pouchitis are lacking. The purpose of this case-control study was to determine whether there are any pathologic features in UC colectomy specimens that may help predict the subsequent development of pouchitis after an IPAA procedure. The study group consisted of 39 UC patients (male/female ratio: 21/18, mean age: 35 years), who had at least 1 episode of pouchitis after an IPAA procedure during the follow-up period (mean: 57 months, range: 12-121 months). There were 26 control patients (male/female ratio: 11/15, mean age: 37 years), all of whom also underwent a total colectomy and IPAA procedure for UC, but did not develop pouchitis during the follow-up period (mean: 78 months, range: 14-223 months). Routinely processed tissues from each colectomy specimen were evaluated for a variety of histologic features, such as extent of colitis, severity of colitis, extent of severe colitis, type and extent of ulceration, presence and severity of appendiceal inflammation, and the presence of active ileitis, and compared between the study and control patients. Pathologic features that were associated with the subsequent development of pouchitis included the presence of severe colitis that extended into the cecum (severe pancolitis), which was present in 7/39 (18%) pouchitis patients, but in none (0%) of the control patients (P = 0.03), early fissuring ulcers [9/39 (23%) pouchitis cases versus 1/26 (4%) controls (P = 0.04)], active inflammation of the appendix [20/32 (63%) pouchitis patients versus 7/19 (31%) controls (P = 0.03)], and appendiceal ulceration [13/32 (41%) pouchitis patients versus none (0%) of the controls (P = 0.002)]. No significant differences in patient gender or age, depth or extent of ulceration, or the presence or absence of "backwash ileitis" were identified between the 2 groups. In conclusion, there are several histologic features in colectomy specimens from UC patients who have undergone an IPAA procedure that may help predict the subsequent development of pouchitis. Of these features, appendiceal ulceration is highly associated with pouchitis.

Chemotaxonomic analysis of bacterial populations colonizing the rectal mucosa in patients with ulcerative colitis

The etiology of ulcerative colitis (UC) is unknown, but evidence links it to bacteria belonging to the normal colonic microbiota. The aims of this study were to characterize bacteria colonizing the rectal epithelium, and to investigate whether significant differences existed in UC. Rectal biopsy specimens were obtained via endoscopy from 9 patients with active colitis and 10 patients without inflammatory bowel disease. Complex bacterial communities colonized the rectal mucosa in all subjects. Overall, 72 bacterial taxa (18 genera) were detected. Twenty species were common to both groups, but only differences in bifidobacteria were statistically significant (P=.005). Peptostreptococci were only detected in patients with UC. Microscopy showed that bacteria in mucosal biofilms often occurred in microcolonies. Interindividual variations in mucosal biofilms made it difficult to assign a role for specific bacteria in UC etiology. However, differences in bifidobacteria and peptostreptococci may implicate these organisms in this disease.

Pouchitis

Pouchitis is one of the commonest and most debilitating complications of a restorative proctocolectomy. The cause remains elusive, though a number of approaches have been shown to alleviate the condition. This review outlines current evidence relating to pouchitis, obtained from randomised and nonrandomised studies. Medline, the Bath Information Data Service (BIDS) and PubMed were searched using the keywords 'pouchitis' and 'inflammatory bowel disease'. In addition, articles were cross-referenced, and the abstracts of recent colorectal meetings studied.

Potato tuber proteins efficiently inhibit human faecal proteolytic activity: implications for treatment of peri-anal dermatitis

BACKGROUND

Frequent diarrhoea after intestinal resections and faecal incontinence in healthy infants may lead to perianal injury. A causative agent may be a high concentration of pancreatic proteases in faeces. The aim of the present study was to assess whether protease inhibitors are applicable for treating and preventing peri-anal dermatitis by inhibiting the initial cause of the inflammation, the faecal proteases.

DESIGN

Proteolytic activity was estimated in faeces of subjects frequently suffering from peri-anal dermatitis: patients with intestinal resections and healthy infants. The development of perianal dermatitis was studied after the construction of a reservoir with ileoanal anastomosis. The inhibitory effect of crude and partly purified potato juice on proteolytic activity of faecal output from patients with intestinal resections and healthy infants was investigated in vitro and in vivo (skin tests).

RESULTS

Faecal protease activity in faeces from patients with intestinal resections and healthy infants was found to be significantly higher than in healthy adults. After the construction of an ileum reservoir, 46 of 48 patients developed a protease-related peri-anal dermatitis. The partly purified protein fraction from potatoes inhibited the larger part of faecal proteases in vitro and completely prevented skin irritation by pancreatic proteases dissolved in sterilized faecal fluid, in a 24-h skin test, on the back of healthy human volunteers.

CONCLUSIONS

Potato proteins contain protease inhibitors, which suppress almost the complete proteolytic activity in faeces. Topical application of potato protease inhibitors might be a novel approach in preventing protease-induced peri-anal dermatitis, and therapeutic studies are needed to confirm our results.

The metabolic activity of fecal microbiota from healthy individuals and patients with inflammatory bowel disease

The hypothesis was studied that intestinal microbial metabolites play a role in the pathogenesis of inflammatory bowel disease. For that purpose, an in vitro model of the colon was inoculated with fresh feces of six healthy individuals and eight inflammatory bowel disease patients. Samples were taken from the model over time to analyze metabolites from both saccharolytic and proteolytic fermentation. Microbiotas from inflammatory bowel disease patients produced significantly more short-chain fatty acids and ammonia than microbiotas from healthy individuals. Furthermore, the branched-chain fatty acid production was 25% higher after inoculation with microbiotas from patients than after inoculation with microbiotas from healthy individuals. Phenolic compounds were produced by all microbiotas, with large interindividual variation. The production of (potentially toxic) metabolites may play a role in the onset or chronicity of inflammatory bowel disease, because they were produced in higher amounts by microbiotas from these patients than by microbiotas from healthy individuals.

Are pANCA, ASCA, or cytokine gene polymorphisms associated with pouchitis? Long-term follow-up in 102 ulcerative colitis patients

OBJECTIVE

Pouchitis is the most frequent complication after ileal pouch-anal anastomosis for ulcerative colitis. This study aims to analyze the frequency and characteristics of pouchitis in long-term follow-up in a large population, and to determine whether a significant association exists between five immunogenetic markers and pouchitis.

METHODS

From a population of over 500 ulcerative colitis patients who had undergone ileal pouch-anal anastamosis 5-12 yr earlier, 102 subjects participated in the study. Using clinical data obtained from interviews and chart reviews, patients were classified into three groups: no pouchitis; 1-2 episodes per year; and >2 episodes per year. Coded sera from the patients were analyzed for ulcerative colitis-associated perinuclear antineutrophil cytoplasmic antibodies and Crohn's disease-associated anti-saccharomyces cerevesiae antibodies. Interleukin-1 receptor antagonist, tumor necrosis factor (TNF), and lymphotoxin beta (lymphotoxin) polymorphisms were also analyzed.

RESULTS

Pouchitis affected 49% of the study population. Antineutrophil cytoplasmic antibodies, anti-saccharomyces cerevesiae antibodies, and lymphotoxin-beta polymorphisms were not associated with pouchitis. Carriage of interleukin-1 receptor antagonist allele 2 was significantly greater among those without pouchitis than those with pouchitis. Patients without pouchitis had a significantly greater carriage rate of TNF allele 2.

CONCLUSIONS

Perinuclear antineutrophil cytoplasmic antibodies and anti-saccharomyces cerevesiae antibodies are not correlated with pouchitis, but interleukin-1 receptor antagonist and TNF may play a role in its development. Further evaluation of these markers in pouchitis will require larger populations, long-term prospective observation, and studies that correlate polymorphisms with specific immunologic functions.

Dysbiosis in inflammatory bowel disease

Abundant data have incriminated intestinal bacteria in the initiation and amplification stages of inflammatory bowel diseases. However, the precise role of intestinal bacteria remains elusive. One theory has suggested a breakdown in the balance between putative species of "protective" versus "harmful" intestinal bacteria--this concept has been termed "dysbiosis". Arguments in support of this concept are discussed.

Once daily high dose probiotic therapy (VSL#3) for maintaining remission in recurrent or refractory pouchitis

BACKGROUND

Ten to 15% of patients with pouchitis experience refractory or recurrent disease. The aim of this study was to evaluate the effectiveness of a single daily high dose probiotic preparation (VSL#3) in maintaining antibiotic induced remission, and quality of life (QOL), for one year in such patients.

METHODS

Patients with pouchitis at least twice in the previous year or requiring continuous antibiotics, associated with a pouchitis disease activity index (PDAI) > or =7 (0 = perfect; 18 = worst), in whom remission was induced by four weeks of combined metronidazole and ciprofloxacin, were randomised to receive VSL#3 6 g or placebo once daily for one year or until relapse. Symptomatic, endoscopic, and histological evaluations were made before, and two and 12 months after randomisation or at the time of relapse. Remission was defined as a clinical PDAI < or =2 and endoscopic PDAI < or =1. Relapse was defined as an increased clinical PDAI score > or =2 and increased endoscopic PDAI score > or =3. QOL was assessed using the inflammatory bowel disease questionnaire (IBDQ).

RESULTS

Thirty six patients were randomised: 20 to VSL#3 and 16 to placebo. Remission was maintained at one year in 17 patients (85%) on VSL#3 and in one patient (6%) on placebo (p<0.0001). The IBDQ score remained high in the VSL#3 group (p = 0.3) but deteriorated in the placebo group (p = 0.0005).

CONCLUSION

The once daily high dose probiotic VSL#3 is effective in maintaining antibiotic introduced remission for at least a year in patients with recurrent or refractory pouchitis. This is associated with a high level of quality of life.

Tropomyosin expression in the ileal pouch: a relationship with the development of pouchitis in ulcerative colitis

OBJECTIVE

Human tropomyosin isoform 5 (hTM5) is a cytoskeletal protein expressed in normal epithelial cells, predominantly in the colon. An autoimmune response toward hTM5 has been reported in ulcerative colitis (UC). Whether hTM5 expression in the ileum is involved in pouchitis is unknown. We assessed hTM5 expression on ileal epithelial cells at surgery and subsequently on development of pouchitis in UC.

METHODS

In a prospective longitudinal study, 28 UC patients undergoing ileal pouch procedures were included. Biopsy samples were taken from the rectum at surgery, as well as from the ileal pouch at surgery and at 6 months. The specimens were stained by immunoperoxidase using the anti-hTM5 monoclonal antibody CG3. Pouchitis was assessed by the Pouchitis Disease Activity Index and hTM5 expression on a scale of 0-3.

RESULTS

At surgery, in rectal samples, hTM5 expression was strong in all epithelial cells including the luminal surface, whereas in ileal samples hTM5 was not expressed or focally expressed only in the goblet cells. At 6 months, the ileum was found to have undergone morphological changes, becoming similar to the colon and showing shortening or reduced number of villi. These changes were associated with a diffuse hTM5 staining in the goblet cells and in the nongoblet epithelial cells lining the crypts and the lumen. The hTM5 score was related to the Pouchitis Disease Activity Index at 6 months (r = 0.82; p = 0.01).

CONCLUSIONS

Expression of hTM5 shows a different pattern in the ileal pouch in UC after surgery. This event is associated with morphological changes of the ileum toward colonic epithelium, related to the development of pouchitis.

Assessment of a new synbiotic preparation in healthy volunteers: survival, persistence of probiotic strains and its effect on the indigenous flora

BACKGROUND

Use of synbiotic preparations as dietary supplement is believed to be a valid approach to restore and maintain colonic microflora. However, only few papers have been published on the assessment of these food supplements and none of them have used molecular biology techniques to evaluate the effects of the probiotic components.

METHODS

Twelve healthy volunteers were recruited. Faecal samples were taken before and at various time points during the administration period and at day 3 in the post-treatment period. Stool culture were performed and amplified ribosomal DNA restriction analysis was used to detect L. paracasei, the major bacterial component of the synbiotic products.

RESULTS

An increase of at least 1 log of L. paracasei-like bacteria was observed in all subjects. An increase of as much as 3 log was seen in subjects who had a low number of L. paracasei-like lactobacilli at the baseline. The counts of L. paracasei-like lactobacilli were found to persist for at least 3 days after discontinuation of intake in healthy volunteers in 7 subjects. Genetic analysis showed that the maiority of vancomicin insensitive lactobacilli were real L. paracasei, as the strains administered with the tested product.

CONCLUSION

This study has shown that the strains of L paracasei administered with a synbiotic dietary supplement are able to survive through the gastrointestinal tract and to persist for at least a few days. It was also shown the efficacy of a synbiotic preparation to positively affect the microflora of healthy volunteers.

Probiotics in inflammatory bowel disease: a critical review

Intestinal bacteria play a key role in inflammatory bowel disease. Probiotics attempt to modify disease by favourably altering bacterial composition, immune status, and inflammation. Until recently, probiotic therapy was considered 'folk' medicine, but there now is emerging interest on the part of the general public and scientific communities in the use of probiotics in human disease. This practical, evidence-based review examines probiotics as therapy for inflammatory bowel disease in humans. There are very few such published randomized clinical trials, but some data exist that possibly show an efficacy of probiotics as maintenance therapy in chronic relapsing pouchitis. Obstacles to providing probiotic therapy include selection of appropriate strains, poorly regulated probiotic quality standardization, processing and human biologic factors which impair probiotic viability, difficulty in maintaining new bacterial populations in the gut, and local product unavailability. Studies have focused on specific inflammatory bowel disease subgroups, limiting general applicability for the practitioner. Basic research highlights the importance of bacteria in these conditions, and the possibility that probiotics will modify physiological parameters. Well-designed, randomized clinical studies are still required to define the role of probiotics as therapeutic agents in inflammatory bowel disease.

Probiotics for the treatment of postoperative complications following intestinal surgery

Probiotics are living micro-organisms that belong to the normal enteric flora and exert a beneficial effect on health and well-being. The rationale for the therapeutic use of probiotics in pouchitis (the most frequent long-term complication following pouch surgery for ulcerative colitis) and postoperative recurrence in Crohn's disease is based on convincing evidence suggesting a crucial role for the endogenous intestinal microflora in the pathogenesis of these conditions. Positive results have been obtained with the administration of highly concentrated probiotic preparations in preventing the onset and relapses of pouchitis. Further controlled studies are needed to establish the efficacy of probiotics in the prophylaxis of postoperative recurrences of Crohn's disease and in the treatment of mild pouchitis.

Short- and long-term outcomes of ileal pouch-anal anastomosis for ulcerative colitis

Ileal pouch-anal anastomosis was an important advancement in the treatment of ulcerative colitis. The aim of this study was to determine whether early complications of ileal pouch-anal anastomosis in patients with ulcerative colitis are associated with poor late functional results.

PATIENTS AND METHODS

Eighty patients were operated on from 1986 to 2000, 62 patients with ileostomy and 18 without. The early and late complications were recorded. Specific emphasis has been placed on the incidence of pouchitis with prolonged follow-up.

RESULTS

The ileostomy was closed an average of 9.2 months after the first operation. Fourteen patients were excluded from the long-term evaluation; 6 patients were lost to regular follow-up, 4 died, and 4 patients still have the ileostomy. Of the 4 patients that died, 1 died from surgical complications. Early complications after operation (41) occurred in 34 patients (42.5%). Late complications (29) occurred in 25 patients as follows: 16 had pouchitis, 3 associated with stenosis and 1 with sexual dysfunction; 5 had stenosis; and there was 1 case each of incisional hernia, ileoanal fistula, hepatic cancer, and endometriosis. Pouchitis occurred in 6 patients (9.8%) 1 year after ileal pouch-anal anastomosis, 9 (14.8%) after 3 years, 13 (21.3%) after 5 years, and 16 (26.2%) after more than 6 years. The mean daily stool frequency was 12 before and 5.8 after operation. One pouch was removed because of fistulas that appeared 2 years later.

CONCLUSIONS

Ileal pouch-anal anastomosis is associated with a considerable number of early complications. There was no correlation between pouchitis and severe disease, operation with or without ileostomy, or early postoperative complications. The incidence of pouchitis was directly proportional to duration of time of follow-up.

The effect of Lactobacillus plantarum 299v on the bacterial composition and metabolic activity in faeces of healthy volunteers: a placebo-controlled study on the onset and duration of effects

AIM

To study the onset and duration of a possible effect of a fermented oatmeal drink containing Lactobacillus plantarum 299v on the composition of the faecal flora of healthy volunteers in a placebo-controlled, double-blind study.

METHODS

Twenty-two participants consumed a fermented oatmeal drink with or without L. plantarum 299v for 4 weeks. Faecal samples were collected weekly: two samples before, four during and four after the consumption of the drink. Several bacterial species were counted and enzyme activities, short-chain fatty acid concentrations, endotoxin concentration and pH were determined. L. plantarum 299v was identified using randomly amplified polymorphic DNA.

RESULTS

In contrast with the placebo group, median lactobacilli counts increased significantly from 4.2 (3.4-6.3) to 8.2 (7.3-8.5) log colony-forming units/gram faeces (P = 0.005) after 1 week of consumption of L. plantarum 299v, thereafter remaining stable during the treatment period. One week after cessation, a significant decrease in lactobacilli [to 4.4 (2.2-6.5) log colony-forming units/gram faeces] was observed (P = 0.003). These lactobacilli were identified as L. plantarum 299v. All other bacterial counts, enzyme activities, short-chain fatty acid concentrations, endotoxin concentration and pH remained unchanged.

CONCLUSIONS

L. plantarum 299v significantly increased the number of lactobacilli in the faecal flora within 1 week, and this effect disappeared within 1 week after cessation of intake. No other changes in bacterial counts and metabolic products were observed.

Prophylaxis of pouchitis onset with probiotic therapy: a double-blind, placebo-controlled trial

BACKGROUND & AIMS

We have recently documented the efficacy of a highly concentrated probiotic preparation (VSL#3) in the prevention of flare-up in patients with chronic pouchitis. The aim of this study was to compare probiotic therapy with VSL#3 versus placebo in the ability to prevent the onset of acute pouchitis during the first year after ileal pouch-anal anastomosis.

METHODS

Forty consecutive patients who underwent ileal pouch-anal anastomosis for ulcerative colitis were randomized to receive either VSL#3 (1 packet containing 900 billion bacteria/day) (n = 20) or an identical placebo (n = 20) immediately after ileostomy closure for 1 year. The patients were assessed clinically, endoscopically, and histologically after 1, 3, 6, 9, and 12 months. Health-related quality of life was assessed using the Inflammatory Bowel Disease Questionnaire.

RESULTS

Two of the 20 patients (10%) treated with VSL#3 had an episode of acute pouchitis compared with 8 of the 20 patients (40%) treated with placebo (log-rank test, z = 2.273; P < 0.05). Treatment with VSL#3 determined a significant improvement in Inflammatory Bowel Disease Questionnaire score, whereas this was not the case with placebo.

CONCLUSIONS

Treatment with VSL#3 is effective in the prevention of the onset of acute pouchitis and improves quality of life of patients with ileal pouch-anal anastomosis.

Assessment of Mucosal Inflammation and Circulation in Response to Probiotics in Patients Operated with Ileal Pouch Anal Anastomosis for Ulcerative Colitis

BACKGROUND

Pouchitis is a common and troublesome condition, and a disturbed microbiological flora and mucosal blood flow in the pouch have been suggested as possible causes. Laser Doppler flowmetry (LDF) has been used successfully to measure gastric and colonic mucosal perfusion in humans. The aim of this study was to evaluate the effect of intervention with probiotics on ileal pouch inflammation and perfusion in the pouch, assessed by endoscopy, histology, fecal calprotectin and LDF.

METHODS

A fermented milk product (Cultura; 500 ml) containing live lactobacilli (La-5) and bifidobacteria (Bb-12) was given daily for 4 weeks to 10 patients operated with ileal-pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). Mucosal perfusion was measured with LDF and the degree of inflammation was examined at predefined levels of the distal bowel by endoscopy and histology. Stool samples were cultured for lactobacilli and bifidobacteria and calprotectin were measured before and after intervention.

RESULTS

The LDF measurements were reproducible in the pelvic pouch at each of the predefined levels, but did not change after intervention. The mucosal perfusion was reduced in the distal compared to the proximal part of the pouch. Calprotectin levels did not change significantly after intervention. The median endoscopic score for inflammation was significantly reduced by 50% after intervention, whereas the histological score did not change significantly.

CONCLUSION

The results suggest that probiotics primarily act superficially, with change of gross appearance of the mucosa at endoscopy, but without significant effect on histological picture, mucosal perfusion or faecal calprotectin, during a relatively short period of 4 weeks.

Use of probiotics in the treatment of inflammatory bowel disease

The gut flora plays a fundamental role in maintaining normal intestinal function. A disturbance of this flora, or the host response to this flora, has been clearly demonstrated to play a role in the pathogenesis of inflammatory bowel disease (IBD). This has led to attempts to modify the bacterial flora with "live non-pathogenic organisms that confer health benefits by improving the microbial balance," otherwise known as probiotics. Recent attention has focused on this potential strategy to treat or prevent IBD. The potential therapeutic benefit is enhanced by the natural and apparently safe approach that probiotics offer. Animal models of colitis have provided the proof of principle that probiotics can prevent and treat established intestinal inflammation. Controlled clinical studies have demonstrated the efficacy of probiotics in the maintenance of remission of pouchitis, prophylaxis of pouchitis after the formation of an ileoanal reservoir, maintenance of remission of ulcerative colitis, and treatment of Crohn's disease. However, large controlled trials are needed to definitively establish the place for probiotics in the treatment of IBD and resolve issues such as the dose, duration, frequency of treatment, and use of single or multiple strains. Research is focusing on establishing the mechanism of action, so that treatments with individually tailored properties are developed and innovative approaches are explored.

Manipulation of the bacterial flora in inflammatory bowel disease

In this chapter we summarize the clinical and experimental data which indicate that bacteria, especially from the endogenous microflora, play a role in the pathogenesis of Crohn's disease, ulcerative colitis and pouchitis. We review the clinical trials, focusing on randomized controlled trials which used antibiotics or probiotics to treat situations of IBD or prevent recurrence, and we discuss the future of this approach.

Colonic delivery of 4-aminosalicylic acid using amylose-ethylcellulose-coated hydroxypropylmethylcellulose capsules

BACKGROUND

4-Aminosalicylic acid has the potential for use in the treatment of diseases of the colon.

AIM

To assess the feasibility of delivering 4-aminosalicylic acid directly to the colon using a hydroxypropylmethylcellulose capsule coated with a mixture of amylose, a polysaccharide metabolized by bacterial enzymes in the colon, and ethylcellulose.

METHODS

Seven healthy male volunteers received, on three separate occasions, an uncoated or amylose-ethylcellulose-coated hydroxypropylmethylcellulose capsule containing 4-aminosalicylic acid Na (550 mg), or an intravenous injection of 4-aminosalicylic acid Na (135 mg). The capsules were radiolabelled with 99mTc to allow their positions in the gastrointestinal tract to be followed using a gamma camera. Plasma and urine samples were collected and assayed for 4-aminosalicylic acid and metabolite concentrations.

RESULTS

The uncoated capsules broke down within 10 min in the stomach, allowing rapid and complete absorption of the drug. The coated capsules remained intact in the upper gastrointestinal tract, and had a median gastric emptying time of 61 min (interquartile range, 77 min) and a median colon arrival time of 363 min (interquartile range, 185 min). For the coated capsules, only the metabolite was detected in the plasma and/or urine after the capsules had reached the colon.

CONCLUSIONS

The specific coating protected the drug until the capsule reached the colon, where 4-aminosalicylic acid was slowly released and absorbed. Thus, such a formulation has the potential for use in the treatment of inflammatory bowel disease.

Probiotics in clinical conditions

Probiotics are nonpathogenic microorganisms which, when ingested, exert a positive influence on the health or physiology of the host. Their mechanisms of action and effects are now studied using the same pharmacological approach as for drugs. This article summarizes and comments on evidence for the positive effects of probiotics in various clinical situations. Substantial evidence can be achieved when randomized controlled trials or meta-analyses show positive results. The clinical situations studied include prevention or treatment of antibiotic-associated disorders, gastroenteritis, and diarrhea, lactose intolerance, intestinal infections and colonization by pathogenic bacteria (including Helicobacter pylori and Clostridium difficile), traveler's diarrhea, irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), colonic cancer, urogenital infections and tumors, allergy (especially atopic eczema), vaccination, and cholesterol lowering. Current probiotics have an excellent safety record--another topic discussed in this article.

Role of probiotics in food hypersensitivity

The definition of probiotics has evolved concomitant with a resurgence of research interest in host-microbe crosstalk. The original definition stated that the live active culture beneficially affects the host by improving its intestinal microbial balance, while current conceptions are based on target- and site- specific effects of clearly defined strains. The establishment of normal microbiota in the intestine represents a key process whereby the intestinal milieu is kept disease-free as it performs its dual function: mounting an inflammatory response to pathogens and maintaining hyporesponsiveness to innocuous antigens. Probiotic therapy is based on this concept of a healthy well-balanced gut microbiota. The probiotic performance of strains differs, however. Different bacteria have clearly defined adherence sites and immunological effects and divergent effects in the healthy versus inflamed mucosa. Hence, notwithstanding recent demonstrations of the important immunoregulatory potential of the healthy well-balanced gut microbiota, current probiotic research is directed towards identification of specific strains with anti-allergenic potential.

Impairment of epithelial transport but not of barrier function in idiopathic pouchitis after ulcerative colitis

BACKGROUND AND AIMS

Little is known of the permeability of ileoanal pouches. Hence the aim of the present study was to determine changes in permeability and mucosal function after ileo-pouchanal anastomosis (IPAA) in patients with ulcerative colitis.

MATERIALS AND METHODS

Biopsies were taken from 43 patients (male:female ratio 28:15; mean age 35.2 (12.5) years) prior to colectomy (ileum prior to pouch), prior to closure of ileostomy (deviation), and after closure of ileostomy (intact pouch) in the case of pouchitis, and from 14 healthy controls. Tissues were mounted in a miniaturised Ussing chamber. Epithelial and subepithelial resistance was determined by transmural impedance analysis. Active Na(+)-glucose cotransport was measured as change in short circuit current after stepwise addition of glucose, and active Cl(-) secretion was measured after stimulation with theophylline and prostaglandin E(2).

RESULTS

Neither epithelial resistance nor mannitol fluxes were significantly altered compared with intact controls, indicating no barrier defect in pouchitis. Subepithelial resistances of intact pouches and pouchitis were increased compared with deviation (18.2 (1.6) and 24.3 (1.5) v. 13.6 (1.0) Omegaxcm(2)) consistent with an adaptive thickening of the subepithelial layer. In contrast, active Cl(-) secretion of pouchitis tissues was reduced versus intact pouch and controls (1.4 (0.3) v. 4.3 (0.7) and 4.6 (0.7) micromol/h/cm(2)), and Na(+)-glucose cotransport of pouchitis was reduced compared with intact pouch and controls (1.8 (0.5) v. 4.2 (0.8) and 8.8 (1.3) micromol/h/cm(2)).

CONCLUSIONS

Ileal mucosa in pouchitis and terminal ileum prior to IPAA exhibit impaired secretory and absorptive transport functions whereas the epithelial barrier function remains unchanged. This differs from findings in ulcerative colitis. Thus the hypothesis that pouchitis represents a remanifestation of ulcerative colitis has to be questioned.

Four-week open-label trial of metronidazole and ciprofloxacin for the treatment of recurrent or refractory pouchitis

BACKGROUND

Preliminary data suggest that short-term antibiotic therapy with a single drug is effective for the treatment of patients with pouchitis. However, some patients are resistant to treatment.

AIM

To evaluate the therapeutic efficacy of a prolonged course of a combination of two antibiotics in patients with refractory or recurrent pouchitis, as well as its impact on their quality of life.

METHODS

Patients with active refractory or recurrent pouchitis were recruited. This was defined as both: (i) a history of pouchitis at least twice in the last 12 months or persistent pouchitis requiring continual intake of antibiotics; and (ii) a Pouchitis Disease Activity Index score 3 7 (best to worst pouchitis=0-18) at the beginning of therapy. Treatment consisted of a combination of metronidazole, 400 or 500 mg twice daily, and ciprofloxacin, 500 mg twice daily, for 28 days. Symptomatic, endoscopic and histological evaluations were undertaken before and after antibiotic therapy using the Pouchitis Disease Activity Index score. Remission was defined as a combination of a Pouchitis Disease Activity Index clinical score of <or= 2, endoscopic score of <or= 1 and total score of <or= 4. The quality of life was assessed with the Inflammatory Bowel Disease Questionnaire, which encompasses bowel, systemic and emotional symptoms as well as social function (worst to best=32-224).

RESULTS

Forty-four patients (24 male, 20 female; median age, 37.5 years) entered the trial and completed treatment. Thirty-six (82%) went into remission. The median Pouchitis Disease Activity Index scores before and after therapy were 12 (range, 8-17) and 3 (range, 1-10), respectively (P < 0.0001). The median Inflammatory Bowel Disease Questionnaire score also significantly improved from 96.5 (range, 74-183) to 175 (range, 76-215) with this therapy (P < 0.0001). The eight patients (five male, three female) who did not go into remission were significantly older (median 47.5 vs. 35 years; P=0.007), had a longer history of pouchitis (95.5 vs. 26 months; P=0.0008), had a greater proportion with chronic pouchitis (chronic/relapsing: 6/2 vs. 9/27; relative risk, 1.6; 95% confidence interval, 1.0-2.4) and tended to have a higher Pouchitis Disease Activity Index score before treatment (median 14.5 vs. 12; P=0.13) than those who went into remission. Even in these eight patients, the median Pouchitis Disease Activity Index score significantly improved from 14.5 (range, 8-16) to 9.5 (range, 7-10) (P=0.0078), as did the Inflammatory Bowel Disease Questionnaire score from 95.5 (range, 74-134) to 127 (range, 76-187) (P=0.039). The Inflammatory Bowel Disease Questionnaire score strongly correlated with the Pouchitis Disease Activity Index score (r=0.79, P < 0.0001), and was significantly related to the patients' overall assessment of satisfaction (P < 0.0001). No serious side-effects were noted.

CONCLUSIONS

Four-week treatment with a combination of metronidazole and ciprofloxacin is highly effective in patients with active recurrent or refractory pouchitis, objectively improving the inflammation and quality of life. The Inflammatory Bowel Disease Questionnaire is a sensitive tool for evaluating patients with pouchitis, and correlates well with disease activity.

Effect of probiotic strains on interleukin 8 production by HT29/19A cells

OBJECTIVES

Promising results from clinical studies on the effect of probiotics as maintenance therapy in inflammatory bowel disease and in the prevention of onset of pouchitis ask for studies to unravel the still poorly understood mechanism of action of probiotics.

METHODS

To evaluate whether the probiotic bacteria that were used in the clinical studies (VSL#3, Escherichia coli Nissle 1917, and Lactobacillus GG) are able to induce chemokine production in epithelial cells, HT29/19A monolayers were incubated with cell debris and cell extract fractions of single strains of the probiotic bacteria in doses ranging from 10(3) to 10(9) colony-forming units/ml for 32 h. Supernatants were measured for interleukin 8 by ELISA.

RESULTS

Lactobacilli and bifidobacteria strains from VSL#3 and Lactobacillus GG did not induce interleukin 8, whereas both cell debris and cell extracts from E. coli Nissle 1917 induced interleukin 8 production in a dose-dependent way. Cell extracts from streptococcal strains induced interleukin 8 when applied at high concentrations.

CONCLUSIONS

Probiotic Gram-positive bacteria did not induce interleukin 8, whereas the nonpathogenic, Gram-negative E. coli Nissle 1917 strain induced interleukin 8 in a dose-dependent way in this culture model. These results suggest that probiotic Gram-positive bacteria and E. coli Nissle 1917 may exert their beneficial effects on the host by a different mechanism of action.

Inflammatory bowel disease: dogmas and heresies

Perception of a disease state by the practising physician is based on how easily the diagnosis can be made and how predictable the outcome of the chosen therapy is. The academic investigator perceives the same disease based on how well its cause and mechanism are understood, and how rational pathophysiology-based treatments are. Because of incomplete knowledge, neither the practising physician nor the academic investigator are comfortable in dealing with inflammatory bowel disease, and both seek help in the dogmas and heresies inevitably associated with chronic disease of unknown aetiology.

Anatomic and functional characteristics of the rat ileal pouch

BACKGROUND

The definitive operation for chronic ulcerative colitis (UC) and familial adenomatous polyposis is total proctocolectomy with ileal pouch-anal anastomosis (IPAA). Mild inflammation (pouchitis) is omnipresent in pouches and becomes severe in 50% of UC patients with IPAA. The etiology of pouchitis is likely due to combined genetic, microbial, and immunologic factors. Epithelial cell exposure to surgical trauma and/or to changes in intestinal bacterial composition may account for the inflammatory infiltrate. Progress in understanding pouchitis is restricted by the lack of suitable animal models.

METHODS

An ileal pouch-rectal anastomosis [IPRA] in rats was developed to reproduce a model of human IPAA and clinical, gross and histologic criteria were determined.

RESULTS

Many shared features with human ileal pouch were observed.

CONCLUSION

IPRA is an important in vivo model to study mechanisms of repair, defense and immunity that may contribute to pouchitis.

Changes in the bacterial flora of the neoterminal ileum after ileocolonic resection for Crohn's disease

OBJECTIVE

Bacterial agents have been implicated in the early recurrence of Crohn's disease after ileocolectomy. The aim of our study was to identify and quantify bacteria associated with the ileal mucosa in patients and controls and to correlate specific bacteria with recurrence.

METHODS

The predominant bacterial microflora of the ileum were enumerated and identified, aerobically and anaerobically, in biopsies obtained at the time of surgery or by endoscopy from 61 patients with Crohn's disease and 10 ileocolectomy controls. The 61 specimens were comprised of 13 ileal biopsies taken from resection specimens, seven taken after ileostomy, and 41 taken after ileocolectomy.

RESULTS

Ileocolectomy induced a significant increase in bacterial counts and variety in the neoterminal ileum in both patients and controls that was not observed in ileostomy biopsies. Comparison between patients and controls revealed greater numbers of Escherichia coli and enterococci in Crohn's disease and of bifidobacteria and ruminococci in controls. Early recurrence was associated with high counts of E. coli and bacteroides and the frequent isolation of fusobacteria.

CONCLUSION

After ileocolectomy, colonization of the neoterminal ileum is increased. Our data suggest that increases in the populations of specific bacteria such as E. coli, enterococci, bacteroides, and fusobacteria may be important in postoperative recurrence of Crohn's disease.

The immunology of inflammatory bowel disease

The dogma of systemic immunity can be ignored in relation to mucosal immunity. These distinct immune systems evolved based on specific environmental realities. Given the potentially hostile environment encountered by the mucosal immune system, it is a necessary adaptation that the overall tone is one of suppression. Breaches in this tone may lead to chronic inflammation. Understanding how specific components and processes of the mucosal immune system interact with the environment will elucidate the pathogenesis of IBD and lead to novel therapeutic approaches.

Etiopathogenesis of inflammatory bowel disease: the importance of the pediatric perspective

Inflammatory bowel disease (IBD) is now recognized as a common chronic disease affecting children and adolescents. This article will review recent advances made in the fields of genetics, epidemiology, gut ecology, and immunology regarding the etiopathogenesis of IBD, with particular emphasis on the contributions made by pediatric studies. Areas where further study of the pediatric age group would be beneficial will be highlighted.

Pouchitis in a rat model of ileal J pouch-anal anastomosis

Endorectal ileal pouch-anal anastomosis (IPAA) has become the operation of choice for patients with chronic ulcerative colitis. Although this procedure improves the quality of life, pouchitis remains a significant postoperative complication. Because our understanding of the pathophysiology of pouchitis may, in part, be due to the lack of small animal model, our aim was to develop a model of IPAA in a rat that mimics its clinical counterpart. Colectomy, proctectomy, construction of an ileal J pouch, and ileal pouch-rectal anastomosis as a model of IPAA was performed in Sprague-Dawley and Lewis rats. Radiographic contrast studies were performed to quantitate intestinal transit. The presence of activated neutrophils was quantified by measuring mucosal myeloperoxidase (MPO) activity. Oxidative stress was quantitated by measuring urinary 8-isoprostane (8-IP) levels. Anaerobic and aerobic bacterial counts were determined on Brucella and tryptic soy agar plates, respectively. Dextran sulfate sodium (DSS) was used to exacerbate ileal J pouch inflammation. Mortality was low, and animals gained weight normally after recovery. Stasis was documented radiographically. MPO levels were elevated (p < 0.05) in the ileal J pouch 30 and 60 days after IPAA, indicating an inflammation that was associated with stasis and bacterial overgrowth. 8-IP levels were elevated by 80% compared with controls. Oral administration of 5% DSS to IPAA rats with further elevated MPO and 8-IP levels in concert with a pouchitis-like syndrome that included the physical, gross, and histologic characteristics of clinical pouchitis. An understanding of the pathophysiology of pouchitis is essential to the future development of new therapeutic modalities. This model is applicable to investigating several key etiologic mechanisms purportedly related to pouchitis.

Preclinical and clinical pharmacology of biotherapeutic agents: Saccharomyces boulardii

Probiotic agents are living microorganisms that, upon ingestion, exert health benefits beyond inherent general nutrition. In this context, we must differentiate between biotherapeutics as approved drugs and dietary supplements and food products containing probiotic bacteria that are not considered drugs. At present the only biotherapeutic agent which is prescribable in some European countries, indicated to relieve specific diseases, is the yeast Saccharomyces boulardii. In this review we consider the various preclinical and clinical aspects of biotherapeutics as basic drugs and the biotherapeutic powers of their use in the treatment of some surgical enteropathies.

Expression of cytokines, inducible nitric oxide synthase, and matrix metalloproteinases in pouchitis: effects of probiotic treatment

OBJECTIVE

The efficacy of probiotic organisms in the treatment of pouchitis has been reported. In the present study, we evaluated the tissue levels of pro- and anti-inflammatory cytokines, nitric oxide synthase, and matrix metalloproteinases in control and inflamed pouches before and after antibiotic and probiotic treatment of patients with acute pouchitis.

METHODS

Pouch biopsy samples were obtained from seven patients with pouchitis before and after antibiotic and probiotic treatment. Tissue samples from five patients with normal pouches were used as controls. Cytokines were determined by ELISA, matrix metalloproteinase activity was evaluated by zymograms, and nitric oxide synthase activity was determined by measuring arginine to citrulline conversion.

RESULTS

Tissue levels of tumor necrosis factor a increased (p < 0.01) in pouchitis relative to uninflamed pouches and reduced after antibiotic and probiotic treatment. Also, interferon y and interleukin 1alpha (IL-1alpha) augmented in pouchitis, but their increase did not reach statistical significance. The latter, however, were lower (p < 0.05) after treatment with the antibiotics and probiotics. Tissue levels of IL-4 and IL-10 were unchanged in inflamed pouches and unaffected by antibiotic treatment. However, IL-10 increased (p < 0.05) after probiotic treatment. Moreover, inflamed pouches had higher levels of inducible nitric oxide synthase and gelatinase activities, which decreased after treatment.

CONCLUSIONS

The ability of antibiotic and probiotic treatments to increase tissue levels of IL-10, at a higher level than those observed in control pouches, and to decrease, to levels present in control pouches, proinflammatory cytokine, inducible nitric oxide synthase, and matrix metalloproteinase activity may suggest a mechanism of action to explain the efficacy of this therapeutic regime in pouchitis.

Activation of signal-transducer and activator of transcription 1 (STAT1) in pouchitis

Activation of signal transducer and activator of transcription 1 (STAT1) is a hallmark of IFN-gamma receptor signal transduction but is also part of the signalling pathway of other cytokines/growth factor receptors. In ulcerative colitis, high levels of activation and expression of STAT1 have been observed in comparison with both Crohn's Disease and normal controls. Pouchitis develops in some patients after Ileal-Pouch-Anal-Anastomosis (IPAA). The pathophysiology and aetiology of pouchitis is still unclear. Recent studies have shown an increased production of proinflammatory cytokines including IFN-gamma. To investigate the expression and activation of STAT1 in pouchitis and the influence of treatment, patients were followed longitudinally from pouch operation. Diagnosis of pouchitis was made by clinical, endoscopic and histological criteria. Biopsies were obtained during routine endoscopy and snap frozen in liquid nitrogen. Nuclear and cytosolic extracts were prepared and the expression and activation of specific transcription factors were assessed by Western blot, electrophoretic mobility shift assay and immunofluorescence. Patients who develop pouchitis show highly increased levels of STAT1 alpha as well as STAT1 beta expression and activation in comparison with both normal pouch and normal ileal mucosa. Improvement of pouchitis during antibiotic therapy relates to a normalization of STAT1 expression and activation. We conclude that activation of STAT1 correlates to clinical disease activity and therefore STAT1 could play an important role in the pathophysiology of pouchitis. Similarities in the pattern of activation of STAT1 in pouchitis and ulcerative colitis may suggest a common pathway in the immunopathophysiology of both diseases.

Protection from gastrointestinal diseases with the use of probiotics

Probiotics are nonpathogenic microorganisms that, when ingested, exert a positive influence on the health or physiology of the host. They can influence intestinal physiology either directly or indirectly through modulation of the endogenous ecosystem or immune system. The results that have been shown with a sufficient level of proof to enable probiotics to be used as treatments for gastrointestinal disturbances are 1) the good tolerance of yogurt compared with milk in subjects with primary or secondary lactose maldigestion, 2) the use of Saccharomyces boulardii and Enterococcus faecium SF 68 to prevent or shorten the duration of antibiotic-associated diarrhea, 3) the use of S. boulardii to prevent further recurrence of Clostridium difficile-associated diarrhea, and 4) the use of fermented milks containing Lactobacillus rhamnosus GG to shorten the duration of diarrhea in infants with rotavirus enteritis (and probably also in gastroenteritis of other causes). Effects that are otherwise suggested for diverse probiotics include alleviation of diarrhea of miscellaneous causes; prophylaxis of gastrointestinal infections, which includes traveler's diarrhea; and immunomodulation. Trials of gastrointestinal diseases that involve the ecosystem are currently being performed, eg, Helicobacter pylori infections, inflammatory bowel disease, and colon cancer.

Enteral inulin does not affect epithelial gene expression and cell turnover within the ileoanal pouch

PURPOSE

This study evaluates the effects of enteral inulin on ileoanal pouch functioning by studying epithelial gene expression, cell turnover, and mucosal morphology.

METHODS

Twenty patients with an ileoanal pouch received 24 g of inulin daily for three weeks, then a four-week wash-out period, and a placebo for three weeks. In this randomized, double-blind, crossover study, biopsy specimens of pouch mucosa were taken after each test period. Mucosal morphology, inflammation, epithelial proliferation, and cell death were assessed histologically. Expressions of proapoptotic and antiapoptotic regulators, intestinal fatty acid-binding protein, and mucin were quantified by Western blotting or enzyme-linked immunosorbent assay. The number of intestinal fatty acid-binding protein expressing cells was histologically assessed and a high iron diamine/Alcian blue staining was performed to discriminate between sulfated and nonsulfated acidic mucins.

RESULTS

Inulin supplementation neither altered mucosal morphology nor influenced inflammation, epithelial cell proliferation, or cell death. The ratio between the proapoptotic and antiapoptotic regulators did not change after inulin supplementation. The number of intestinal fatty acid-binding protein-producing enterocytes and the intestinal fatty acid-binding protein expression level increased after inulin treatment, but did not reach statistical significance. The intestinal fatty acidbinding protein expression level correlated with the Pouchitis Disease Activity Index, which was at the brink of significance (P = 0.06). Mucin expression and the ratio between sulfated and nonsulfated acidic mucins were not altered by inulin supplementation.

CONCLUSION

In this prospective study, inulin supplementation did not significantly alter pouch mucosal functioning because neither epithelial homeostasis nor epithelial gene expression was significantly altered by enteral inulin.

Oral bacteriotherapy as maintenance treatment in patients with chronic pouchitis: a double-blind, placebo-controlled trial

BACKGROUND & AIMS

Pouchitis is the major long-term complication after ileal pouch-anal anastomosis for ulcerative colitis. Most patients have relapsing disease, and no maintenance treatment study has been performed. We evaluated the efficacy of a probiotic preparation (VSL#3) containing 5 x 10(11) per gram of viable lyophilized bacteria of 4 strains of lactobacilli, 3 strains of bifidobacteria, and 1 strain of Streptococcus salivarius subsp. thermophilus compared with placebo in maintenance of remission of chronic pouchitis.

METHODS

Forty patients in clinical and endoscopic remission were randomized to receive either VSL#3, 6 g/day, or an identical placebo for 9 months. Patients were assessed clinically every month and endoscopically and histologically every 2 months or in the case of a relapse. Fecal samples were collected for stool culture before and after antibiotic treatment and each month during maintenance treatment.

RESULTS

Three patients (15%) in the VSL#3 group had relapses within the 9-month follow-up period, compared with 20 (100%) in the placebo group (P < 0.001). Fecal concentration of lactobacilli, bifidobacteria, and S. thermophilus increased significantly from baseline levels only in the VSL#3-treated group (P < 0.01).

CONCLUSIONS

These results suggest that oral administration of this new probiotic preparation is effective in preventing flare-ups of chronic pouchitis.

Probiotics in infective diarrhoea and inflammatory bowel diseases

Bacteria are present throughout the gastrointestinal tract, but their pattern and concentration vary greatly. Probiotics are living organisms that supply beneficial health effects to the host. So far the beneficial effects of probiotics have been shown, almost exclusively, under poorly defined experimental conditions. There are little convincing data from well-designed, double-blind controlled trials supporting health-promoting effects. The use of probiotics to treat gastrointestinal infections has produced contrasting results. Apart from information on rotavirus infection in children, there is no convincing evidence from controlled studies on the efficacy of probiotics in the prevention or treatment of infective diarrhoea. However, experimental and clinical studies suggest that there are potential therapeutic roles for probiotics in the treatment of inflammatory bowel diseases. This review focuses on the available data concerning the mechanisms of action of probiotics, and on the results from clinical studies using probiotics to treat infective diarrhoea and inflammatory bowel disease.

Role of stasis and oxidative stress in ileal pouch inflammation

BACKGROUND

Although ileal pouch-anal anastomosis has become the operation of choice for patients with chronic ulcerative colitis and familial adenomatous polyposis coli, ileal pouch inflammation or pouchitis remains a significant postoperative complication. Numerous factors such as fecal stasis have been implicated in the etiology of pouchitis; however, pouchitis remains poorly understood due to the lack of a small animal model. One of the primary goals of this study was to surgically create a reservoir or U-pouch in the ileum of a rat in which stasis would occur in a manner that was unimpeded by other complicating factors such as a colectomy. This model would allow investigation of the hypothesis that intestinal stasis leads to biochemical changes that predispose the ileal pouch to inflammation and oxidative stress.

MATERIALS AND METHODS

A U-pouch was surgically created in the terminal ileum of Lewis rats just proximal to the ileocecal valve without a colectomy. Stasis was assessed by serial barium radiographs over 48 h. Thirty days after surgery, mucosa was obtained from the ileal U-pouches and nonoperated ileum to assess inflammation and neutrophil infiltration histologically and by measuring myeloperoxidase activity. Oxidative stress was assessed by measuring 8-isoprostane levels in urine. Once the model was validated and it was established that stasis and inflammation occurred in the pouch, either vitamin E or allopurinol was administered for 30 days after which myeloperoxidase and 8-isoprostane levels were again measured.

RESULTS

In our experimental model, ileal stasis resulted in increases in both mucosal myeloperoxidase activity and urinary 8-isoprostane levels, suggesting that oxidative stress was associated with stasis. Thirty-day treatment with vitamin E or allopurinol reduced ileal myeloperoxidase activity and urinary 8-isoprostane levels.

CONCLUSION

These studies demonstrated that stasis in the ileum occurred and was associated with neutrophil infiltration and oxidative stress. Antioxidant treatment reduced the inflammatory response suggesting a role for antioxidant therapy in the treatment of pouchitis.

Pouchitis: extracolonic manifestation of ulcerative colitis?

Pouchitis is the most frequent complication of ileal pouch-anal anastomosis for treatment of ulcerative colitis. There are several possible explanations. Among them, we focus on the one that considers pouchitis as an extracolonic manifestation of ulcerative colitis. The aim of this study was to investigate the association between pouchitis and extra-intestinal manifestations (EIM), which are frequent in these patients. Sixty patients underwent restorative proctocolectomy with an ileal J pouch (IPAA) from September 1984 to December 1998. Pouchitis was defined by clinical, endoscopic, and histologic criteria. The following extra-intestinal manifestations were studied: articular, cutaneous, hepatobiliary, ocular, genitourinary, and growth failure. Thirteen patients, of which 10 were female (76.9%), developed one or more episodes of pouchitis. Twelve patients of this group (92.3%) presented some kind of extra-intestinal manifestation, 4 pre-operatively (exclusively), 2 post-operatively (exclusively), and 6 both pre- and post-operatively (1.7 per patient). Twenty patients (42.7%) of the 47 without pouchitis did not present extra-intestinal manifestations; 10/35 (28. 5%) of females had pouchitis, compared to 3/35 (12.0%) of men. Pouchitis was more frequent among females, though not statistically significant. EIM increases the risk of pouchitis. Pouchitis is related to EIM in 92.3 % of cases, corroborating the hypothesis that it could be an extracolonic manifestation of ulcerative colitis.