Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022104 (irritable bowel syndrome)
 8,033 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Irritable bowel syndrome (IBS) is a debilitating disease, which is characterised by recurrent abdominal cramping and pain, and is associated with either constipation and/or diarrhoea. It is approximately twice as prevalent in women as it is in men and is among the most common gastrointestinal (GI) disorders encountered in primary care. The aetiology of the disease is poorly understood but may include motility dysregulation, visceral sensitivity, inflammation, bacterial infection, dietary antigens, psychological stress, GI surgery or a gut-brain phenomenon. At present, there is no acceptable treatment for IBS, although recent advances indicate that some relief may be achieved by the administration of compounds that act on 5-HT (serotonin) receptors. This suggestion is the result of numerous studies which have shown that 5-HT may exert a number of diverse effects on human GI tissues. In addition, it has emerged that the levels of the 5-HT metabolite (5-HIAA) are raised in the plasma of IBS patients and that administration of 5-HT-like compounds may mimic the symptoms of IBS. It has therefore been proposed that therapy with compounds that act at 5-HT receptors will return the intestine to normal activity and alleviate the pain experienced by these patients. One compound (alosetron, a 5-HT3 receptor antagonist) has already been released onto the market but showed benefit in female patients only and only in those whose primary symptom was diarrhoea. In addition, the compound was recently withdrawn following concerns over its safety. The reasons why alosetron only appears to show efficacy in females, why these treatments are only effective in a subset of the population of IBS patients and why alosetron elicits its particular side effect profile have not been elucidated. One further serotonergic compound, tegaserod (Zelmac, a 5-HT4 receptor agonist), has shown promise for the treatment of patients with constipation-predominant IBS and is currently in pre-registration for this indication. It is clear, however, that further research will have to take place before the utility of serotonergic modulation in the treatment of IBS can be fully validated.
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PMID:Serotonergic modulation and irritable bowel syndrome. 1598 96

Traveler's diarrhea is usually an acute, self-limited illness; however, in some patients, enteric symptoms can persist for weeks, months, or years. It has been estimated that up to 3% of patients with traveler's diarrhea have symptoms for >30 days. The differential diagnosis includes persistent infection, coinfection, temporary postinfection phenomena, or malabsorptive syndromes. Once these possibilities are excluded, and if symptoms persist, a diagnosis of postinfectious irritable bowel syndrome (PI-IBS) becomes more likely. PI-IBS has recently become a topic of considerable clinical and investigative interest, because evidence validating it as a diagnosis and elucidating its pathophysiological mechanisms has accumulated. Epidemiological evidence suggests that PI-IBS is a relatively common sequela of acute gastroenteritis. Experimental evidence suggests that chronic inflammation following acute bacterial infection has a pathophysiological role in the development of PI-IBS. A fuller understanding of these pathophysiological mechanisms will lead to a more directed therapeutic approach and, perhaps, a reevaluation of prophylaxis for traveler's diarrhea as a means of primary prevention of PI-IBS.
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PMID:Sequelae of traveler's diarrhea: focus on postinfectious irritable bowel syndrome. 1626 22

A significant proportion of adults believe they suffer from food allergy, and 20-65% of patients with irritable bowel syndrome (IBS) attribute their symptoms to something in food that activates an abnormal response. This systematic review evaluates the role of food allergy in aetiology and management of these disorders. Activation of gastrointestinal mucosal immune system may be one of the causative factors in the pathogenesis of functional dyspepsia and IBS. This activation may result from effects of bacterial infection or other luminal factors including commensal microbial flora and food antigens. Some studies have reported on the role of food allergy in IBS; only one epidemiological study on functional dyspepsia and food allergy has been published. The mechanism by which food activates mucosal immune system is uncertain, but food specific IgE and IgG4 appeared to mediate the hypersensitivity reaction in a subgroup of IBS patients. Exclusion diets based on skin prick test, RAST for IgE or IgG4, hypoallergic diet and clinical trials with oral disodium cromoglycate have been conducted, and some success has been reported in a subset of IBS patients. Further well-controlled studies are needed to establish whether food allergy plays a role in the pathophysiology of functional dyspepsia and IBS.
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PMID:Is there a role of food allergy in irritable bowel syndrome and functional dyspepsia? A systematic review. 1691 24

The irritable bowel syndrome is the most frequent and most important functional bowel disease. It is characterized by a combination of abdominal pain, alterations of bowel habits (diarrhea, constipation) and meteorism. Probably, visceral hypersensitivity, motility disturbances, food intolerance, immunologic and microbiologic alterations and psychosomatic influences contribute to symptoms. In a relevant subgroup of patients the disease is triggered by bacterial infection. These patients usually have diarrhea-predominant disease. Irritable bowel syndrome can be diagnosed if typical symptoms are present and after relevant organic differential diagnoses have been excluded by selective biochemical investigations, abdominal ultrasonography and, if applicable, by colonoscopy. These diagnostic procedures are an important basis for therapeutic interventions and need to be complemented by clear information about the diagnosis and the benign long-term course of the disease. Medical therapy concentrates on treatment of predominant symptoms, i.e. pain, diarrhea, constipation and meteorism.
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PMID:[Therapy of functional bowel disorders]. 1736 33

Irritable bowel syndrome (IBS) is characterized by abdominal pain and alterations in bowel habits. Several pathogenetic factors, such as altered intestinal motility, visceral hypersensitivity, serotonin system abnormalities and psychic disturbances have been identified. Recently, a pathogenetic role of intestinal microflora has been shown in IBS: viral or bacterial infection can trigger post-infectious IBS; some patients have small intestinal bacterial overgrowth; the composition of patients' enteric flora is altered; and minimal inflammatory changes, consistent with the pro-inflammatory role of bacteria, have been demonstrated. Probiotics may, therefore, offer a rational therapeutic approach to IBS. The data available on the use of probiotics in IBS are still limited and results of controlled clinical trials are contradictory because they have been performed using different species, dosages, treatment durations and end-points for results evaluation. A critical evaluation of the therapeutic role of the various probiotics in IBS is presented in this article.
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PMID:Probiotic agents in the treatment of irritable bowel syndrome. 1790 Mar 96

Gastrointestinal infection is ubiquitous worldwide though the pattern of infection varies widely. Poor hygiene and lack of piped water is associated with a high incidence of childhood infection, both viral and bacterial. However in developed countries bacterial infection is commoner in young adults. Studies of bacterial infections in developed countries suggest 75% of adults fully recover, however around 25% have long lasting changes in bowel habit and a smaller number develop the irritable bowel syndrome (IBS). Whether the incidence is similar in developing countries is unknown. Post-infective IBS (PI-IBS) shares many features with unselected IBS but by having a defined onset allows better definition of risk factors. These are in order of importance: severity of initial illness, smoking, female gender and adverse psychological factors. Symptoms may last many years for reasons which are unclear. They are likely to include genetic factors controlling the immune response, alterations in serotonin signaling, low grade mucosal inflammation maintained by psychological stressors and alterations in gut microbiota. As yet there are no proven specific treatments, though 5HT(3) receptor antagonists, anti-inflammatory agents and probiotics are all logical treatments which should be examined in large well-designed randomised placebo controlled trials.
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PMID:Infection, inflammation, and the irritable bowel syndrome. 1971 78

As a rule, travelers' diarrhea is a self-limited bacterial infection that affects approximately 40 % of travelers to developing countries. Health-care professionals who see returning travelers have noted that some travelers afflicted with diarrhea do not recover completely but, instead, develop chronic diarrhea or a persistent change in gastrointestinal function. Concurrent with this observation has been the recognition that in many patients with long-standing irritable bowel syndrome, an episode of traveler's diarrhea or gastroenteritis preceded the onset of symptoms. Before a diagnosis of postinfectious irritable bowel syndrome is considered, other diagnostic considerations must be excluded. This review will examine an approach to the patient with chronic diarrhea posttravel.
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PMID:Chronic diarrhea in travelers. 2353 49

Crohn's disease (CD) is notably characterized by the expansion of visceral fat with small adipocytes expressing a high proportion of anti-inflammatory genes. Conversely, visceral fat depots in ulcerative colitis (UC) patients have never been characterized. Our study aims were a) to compare adipocyte morphology and gene expression profile and bacterial translocation in omental (OM) and mesenteric (MES) adipose tissue of patients with UC and CD, and b) to investigate the effect of bacterial infection on adipocyte proliferation in vitro. Specimens of OM and MES were collected from 11 UC and 11 CD patients, processed and examined by light microscopy. Gene expression profiles were evaluated in adipocytes isolated from visceral adipose tissue using microarray and RTqPCR validations. Bacteria within adipose tissue were immuno-detected by confocal scanning laser microscopy. Adipocytes were incubated with Enterococcus faecalis and cells counted after 24 h. Morphology and molecular profile of OM and MES revealed that UC adipose tissue is less inflamed than CD adipose tissue. Genes linked to inflammation, bacterial response, chemotaxis and angiogenesis were down-regulated in adipocytes from UC compared to CD, whereas genes related to metallothioneins, apoptosis pathways and growth factor binding were up-regulated. A dense perinuclear positivity for Enterococcus faecalis was detected in visceral adipocytes from CD, whereas positivity was weak in UC. In vitro bacterial infection was associated with a five-fold increase in the proliferation rate of OM preadipocytes. Compared to UC, visceral adipose tissue from CD is more inflamed and more colonized by intestinal bacteria, which increase adipocyte proliferation. The influence of bacteria stored within adipocytes on the clinical course of IBD warrants further investigations.
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PMID:Differences in visceral fat and fat bacterial colonization between ulcerative colitis and Crohn's disease. An in vivo and in vitro study. 2420 44

Patients with Crohn's Disease and Ulcerative Colitis infected with Adherent-Invasive Escherichia coli strains constitute the largest group among Inflammatory Bowel Disease subjects, when taking into account all known etiological agents of the disease. A possible link between these pathogenic bacteria and inflammation process has gained the confidence in recently published papers. Observed enteric neuroglial cells apoptosis and epithelial gaps of ileum are probably the key manifestations of inflammation, which has been shown in IBD patients in contrary to the samples taken from healthy individuals. The cascade of consecutive events from bacterial infection via inflammation to excessive apoptosis in IBD patients leads up to the aim of our hypothesis about designing of new therapeutic strategy directed to Adherent-Invasive E. coli strains. The main advantage of biological method, which will rely on application of E. coli Nissle 1917 strain as a carrier for specific recombinant colicins against AIEC strains, could probably cause a long-lasting remission of inflammation in CD and UC patients.
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PMID:Use of Escherichia coli Nissle 1917 producing recombinant colicins for treatment of IBD patients. 2737 48