Peter J. Whorwell

The irritable bowel severity scoring system: a simple method of monitoring irritable bowel syndrome and its progress

Background: The clinical assessment and investigation of irritable bowel syndrome would be greatly facilitated by the introduction of a simple, easy to use severity scoring system. Such a system, developed in our department over a number of years, has been submitted to validation in a total of 141 patients and 40 healthy controls.

Guidelines on the irritable bowel syndrome: mechanisms and practical management

Background: IBS affects 5–11% of the population of most countries. Prevalence peaks in the third and fourth decades, with a female predominance. Aim: To provide a guide for the assessment and management of adult patients with irritable bowel syndrome. Methods: Members of the Clinical Services Committee of The British Society of Gastroenterology were allocated particular areas to produce review documents. Literature searching included systematic searches using electronic databases such as Pubmed, EMBASE, MEDLINE, Web of Science, and Cochrane databases and extensive personal reference databases. Results: Patients can usefully be classified by predominant bowel habit. Few investigations are needed except when diarrhoea is a prominent feature. Alarm features may warrant further investigation. Adverse psychological features and somatisation are often present. Ascertaining the patients’ concerns and explaining symptoms in simple terms improves outcome. IBS is a heterogeneous condition with a range of treatments, each of which benefits a small proportion of patients. Treatment of associated anxiety and depression often improves bowel and other symptoms. Randomised placebo controlled trials show benefit as follows: cognitive behavioural therapy and psychodynamic interpersonal therapy improve coping; hypnotherapy benefits global symptoms in otherwise refractory patients; antispasmodics and tricyclic antidepressants improve pain; ispaghula improves pain and bowel habit; 5-HT3 antagonists improve global symptoms, diarrhoea, and pain but may rarely cause unexplained colitis; 5-HT4 agonists improve global symptoms, constipation, and bloating; selective serotonin reuptake inhibitors improve global symptoms. Conclusions: Better ways of identifying which patients will respond to specific treatments are urgently needed.

The prevalence, patterns and impact of irritable bowel syndrome: an international survey of 40,000 subjects.

Aim : To determine the prevalence, symptom pattern and impact of the irritable bowel syndrome, across eight European countries, using a standardized methodology.

Efficacy of an encapsulated probiotic Bifidobacterium infantis 35624 in women with irritable bowel syndrome.

BACKGROUND:Probiotic bacteria exhibit a variety of properties, including immunomodulatory activity, which are unique to a particular strain. Thus, not all species will necessarily have the same therapeutic potential in a particular condition. We have preliminary evidence that Bifidobacterium infantis 35624 may have utility in irritable bowel syndrome (IBS).OBJECTIVES:This study was designed to confirm the efficacy of the probiotic bacteria B. infantis 35624 in a large-scale, multicenter, clinical trial of women with IBS. A second objective of the study was to determine the optimal dosage of probiotic for administration in an encapsulated formulation.METHODS:After a 2-wk baseline, 362 primary care IBS patients, with any bowel habit subtype, were randomized to either placebo or freeze-dried, encapsulated B. infantis at a dose of 1 × 106, 1 × 108, or 1 × 1010, cfu/mL for 4 wk. IBS symptoms were monitored daily and scored on to a 6-point Likert scale with the primary outcome variable being abdominal pain or discomfort. A composite symptom score, the subjects global assessment of IBS symptom relief, and measures of quality of life (using the IBS-QOL instrument) were also recorded.RESULTS:B. infantis 35624 at a dose of 1 × 108 cfu was significantly superior to placebo and all other bifidobacterium doses for the primary efficacy variable of abdominal pain as well as the composite score and scores for bloating, bowel dysfunction, incomplete evacuation, straining, and the passage of gas at the end of the 4-wk study. The improvement in global symptom assessment exceeded placebo by more than 20% (p < 0.02). Two other doses of probiotic (1 × 106 and 1 × 1010) were not significantly different from placebo; of these, the 1 × 1010 dose was associated with significant formulation problems. No significant adverse events were recorded.CONCLUSIONS:B. infantis 35624 is a probiotic that specifically relieves many of the symptoms of IBS. At a dosage level of 1 × 108 cfu, it can be delivered by a capsule making it stable, convenient to administer, and amenable to widespread use. The lack of benefits observed with the other dosage levels of the probiotic highlight the need for clinical data in the final dosage form and dose of probiotic before these products should be used in practice.

Intestinal microbiota in functional bowel disorders: a Rome foundation report

It is increasingly perceived that gut host–microbial interactions are important elements in the pathogenesis of functional gastrointestinal disorders (FGID). The most convincing evidence to date is the finding that functional dyspepsia and irritable bowel syndrome (IBS) may develop in predisposed individuals following a bout of infectious gastroenteritis. There has been a great deal of interest in the potential clinical and therapeutic implications of small intestinal bacterial overgrowth in IBS. However, this theory has generated much debate because the evidence is largely based on breath tests which have not been validated. The introduction of culture-independent molecular techniques provides a major advancement in our understanding of the microbial community in FGID. Results from 16S rRNA-based microbiota profiling approaches demonstrate both quantitative and qualitative changes of mucosal and faecal gut microbiota, particularly in IBS. Investigators are also starting to measure host–microbial interactions in IBS. The current working hypothesis is that abnormal microbiota activate mucosal innate immune responses which increase epithelial permeability, activate nociceptive sensory pathways and dysregulate the enteric nervous system. While we await important insights in this field, the microbiota is already a therapeutic target. Existing controlled trials of dietary manipulation, prebiotics, probiotics, synbiotics and non-absorbable antibiotics are promising, although most are limited by suboptimal design and small sample size. In this article, the authors provide a critical review of current hypotheses regarding the pathogenetic involvement of microbiota in FGID and evaluate the results of microbiota-directed interventions. The authors also provide clinical guidance on modulation of gut microbiota in IBS.

CONTROLLED TRIAL OF HYPNOTHERAPY IN THE TREATMENT OF SEVERE REFRACTORY IRRITABLE-BOWEL SYNDROME

30 patients with severe refractory irritable-bowel syndrome were randomly allocated to treatment with either hypnotherapy or psychotherapy and placebo. The psychotherapy patients showed a small but significant improvement in abdominal pain, abdominal distension, and general well-being but not in bowel habit. The hypnotherapy patients showed a dramatic improvement in all features, the difference between the two groups being highly significant. In the hypnotherapy group no relapses were recorded during the 3-month follow-up period, and no substitution symptoms were observed.

Interleukin 10 genotypes in irritable bowel syndrome: evidence for an inflammatory component?

Background and aims: Inflammation may play a role in the pathogenesis of irritable bowel syndrome in some individuals, such as in those who develop symptoms following a dysenteric illness. Persisting inflammation, resulting from an imbalance of cytokines regulating the inflammatory response, is one possible mechanism. As the elaboration of cytokines is under genetic control, this study was designed to establish whether there might be a genetic predisposition to an altered pattern of anti-inflammatory cytokine production in patients with irritable bowel syndrome. Subjects: A total of 230 unselected patients with irritable bowel syndrome and 450 healthy, ethnically matched controls were studied. Methods: DNA was extracted from peripheral blood leucocytes of subjects. Allele and genotype frequencies were determined for the anti-inflammatory cytokine interleukin 10 at the site (−1082) concerned with production in lymphocytes. Transforming growth factor β1 (codons 10 and 25) genotypes were also examined in a smaller group of subjects. Results: Patients with irritable bowel syndrome had significantly reduced frequencies of the high producer genotype for interleukin 10 than controls (21% v 32%; p=0.003). There was no apparent relationship with any particular bowel habit subtype. Genotypes for transforming growth factor β1 were not altered. Conclusions: These preliminary results suggest that at least some patients with irritable bowel syndrome may be genetically predisposed to produce lower amounts of the anti-inflammatory cytokine interleukin 10. This lends some support to the hypothesis that there may be an inflammatory or genetic component in some cases of this condition and that further studies in specific irritable bowel syndrome subgroups are justified.

Symptoms of irritable bowel syndrome in ulcerative colitis in remission

The prevalence of symptoms suggestive of a motility disturbance similar to the irritable bowel syndrome was investigated in 98 patients with ulcerative colitis in remission, and a similar number of age- and sex-matched healthy controls. Thirty-three per cent of patients compared with 7% of controls fulfilled the criteria for such a syndrome (p<0·01). Contrary to expectations these symptoms were not confined to patients with distal disease. Other symptoms such as constipation were also very common in the colitic group (31%).

Hypnotherapy in severe irritable bowel syndrome: further experience.

Fifteen patients with severe intractable irritable bowel syndrome previously reported as successfully treated with hypnotherapy, have now been followed up for a mean duration of 18 months. All patients remain in remission although two have experienced a single relapse overcome by an additional session of hypnotherapy. Experience with a further 35 patients is reported giving a total group of 50. This group was divided into classical cases, atypical cases and cases exhibiting significant psychopathology. The response rates were 95%, 43%, and 60% respectively. Patients over the age of 50 years responded very poorly (25%) whereas those below the age of 50 with classical irritable bowel syndrome exhibited a 100% response rate. This study confirms the successful effect of hypnotherapy in a larger series of patients with irritable bowel syndrome and defines some subgroup variations.

Clinical trial: the effects of a fermented milk product containing Bifidobacterium lactis DN‐173 010 on abdominal distension and gastrointestinal transit in irritable bowel syndrome with constipation

Background  A sensation of abdominal swelling (bloating) and actual increase in girth (distension) are troublesome features of irritable bowel syndrome (IBS), which is more common in patients with constipation, especially those with delayed transit.