Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017160 (gastroenteritis)
 11,398 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A small but significant subgroup of patients with irritable bowel syndrome (IBS) report a sudden onset of their IBS symptoms after a bout of gastroenteritis. Population-based surveys show that although a history of neurotic and psychologic disorders, pain-related diseases, and gastroenteritis are all risk factors for developing IBS, gastroenteritis is the most potent. More toxigenic organisms increase the risk 11-fold, as does an initial illness lasting more than 3 weeks. Hypochondriasis and adverse life events double the risk for postinfective (PI)-IBS and may account for the increased proportion of women who develop this syndrome. PI-IBS is associated with modest increases in mucosal T lymphocytes and serotonin-containing enteroendocrine cells. Animal models and some preliminary human data suggest this leads to excessive serotonin release from the mucosa. Both the histologic changes and symptoms in humans may last for many years with only 40% recovering over a 6-year follow-up. Celiac disease, microscopic colitis, lactose intolerance, early stage Crohn's disease, and bile salt malabsorption should be excluded, as should colon cancer in those over the age of 45 years or in those with a positive family history. Treatment with Loperamide, low-fiber diets, and bile salt- binding therapy may help some patients. Serotonin antagonists are logical treatments but have yet to be evaluated.
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PMID:Postinfectious irritable bowel syndrome. 1276 24

Infection by pathogenic organisms leads to mucosal damage and disruption of the gut's extensive commensal flora, factors which may lead to prolonged bowel dysfunction. Six to 17% of unselected irritable bowel syndrome (IBS) patients believe their symptoms began with an infection, which is supported by prospective studies showing a 4%-31% incidence of postinfectious IBS-(PI) following bacterial gastroenteritis. The wide range of incidence can be accounted for by differences in risk factors, which include in order of magnitude; severity of initial illness > bacterial toxigenicity > hypochondriasis, depression and neuroticism, and adverse life events in the previous 3 months. PI-IBS has been reported after Campylobacter, Salmonella, and Shigella infections. Serial biopsies after Campylobacter jejuni gastroenteritis show an initial inflammatory infiltrate, with an increase in enterochromaffin (EC) cells, which in most cases subsides over the next 6 months. Those who go on to develop IBS show increased numbers of EC and lymphocyte cell counts at 3 months compared with those who do not develop IBS. Interleukin-1beta mRNA levels are increased in the mucosa of those who develop PI-IBS, who also show increased gut permeability. Recover can be slow, with approximately 50% still having symptoms at 5 years. Recent studies suggest an increase in peripheral blood mononuclear cell cytokine production in unselected IBS, an abnormality that may be ameliorated by probiotic treatment. The role of small-bowel bacterial overgrowth in IBS is controversial, but broad-spectrum antibiotics do have a temporary benefit in some patients. More acceptable long-term treatments altering gut flora are awaited with interest.
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PMID:Role of infection in irritable bowel syndrome. 1723 25

Unexplained diarrhoea is a frequent indication for gastroenterologic referral, and after full investigation the most common final diagnosis is irritable bowel syndrome (IBS). Some patients with IBS describe an acute onset of symptoms following infective gastroenteritis. Postinfective IBS affects 7% to 31% of individuals infected, and appears to be a nonspecific response to injury which has been reported following Salmonella-, Campylobacter-, and Shigella-related IBS. The strongest risk factor for developing postinfective IBS is severity of the initial diarrhoea illness, but toxigenicity of the infected bacteria, age <60 years, and female sex also are important risk factors. Adverse life events, hypochondriasis, and depression are also important, as is increased enteroendocrine cell and lymphocyte numbers in rectal biopsies. Postinfective IBS and IBS with diarrhoea without an infectious onset both show increased postprandial release of serotonin, whilst constipated patients show a depressed release. Several studies suggest impairment of the serotonin transporter in IBS, which in animal studies has been shown to occur following a range of inflammatory insults. Clinical conditions with an inflammatory basis, such as coeliac and Crohn disease, also are characterised by excess postprandial serotonin release. Several studies report evidence of low-grade inflammation in IBS with diarrhoea. However, reliable markers of low-grade inflammation that may predict response to serotonin antagonists or other anti-inflammatory agents remain a goal for future research.
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PMID:Serotonin, inflammation, and IBS: fitting the jigsaw together? 1818 71