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)

Management strategies in Crohn's disease and ulcerative colitis should be based on up-to-date information on disease distribution, extent, activity and complications. A system of structured analysis is suggested, with separate consideration of destructive ulceration, inflammatory activity and other factors. Direct investigation of gut immunity by using whole gut lavage fluid (WGLF) is a valuable new technique of clinical investigation in IBD and related disorders. Recent studies have shown that the concentrations of plasma-derived proteins in WGLF provide objective measures of disease activity; and that this activity is a separate phenomenon from destructive ulceration and fibrosis. Neutrophils in the lumen can be in- investigated by cytology, or by assay of neutrophil elastase in WGLF. Cytokines and other immuno-regulatory mediators can also be detected. These new techniques can provide a description of intestinal immunity and inflammation, based on a non-invasive test of 2-4 h duration. Work in progress shows that patients who respond clinically to elemental diet treatment have unusually high concentrations of soluble IL2 receptor in WGLF; cytokine profiles may facilitate the selection of patients suitable for other new treatment modalities.
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PMID:Analysis of disease distribution, activity and complications in the patient with inflammatory bowel disease. 797 42

Although physiological stimuli in the healthy gastrointestinal tract are generally not associated with conscious perception, chronic abdominal discomfort and pain are the most common symptoms resulting in patient visits with gastroenterologists. Symptoms may be associated with inflammatory conditions of the gut or occur in the form of so-called functional disorders. The majority of patients with functional disorders appear to primarily have inappropriate perception of physiological events and altered reflex responses in different gut regions. Recent breakthroughs in the neurophysiology of somatic and visceral sensation are providing a series of plausible mechanisms to explain the development of chronic hyperalgesia within the human gastrointestinal tract. A central concept to all these mechanisms is the development of hyperexcitability of neurons in the dorsal horn, which can develop either in response to peripheral tissue irritation or in response to descending influences originating in the brainstem. Taking clinical characteristics and the concept of central hyperexcitability into account, a model is proposed by which abdominal pain from chronic inflammatory conditions of the gut and functional bowel disorders such as noncardiac chest pain, nonulcer dyspepsia, and irritable bowel syndrome could develop by multiple mechanisms either alone or in combination.
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PMID:Basic and clinical aspects of visceral hyperalgesia. 783 12

To investigate the influence of the brain-gut interactions on the pathophysiology of irritable bowel syndrome (IBS), we compared such patients (n = 10) with healthy control subjects (n = 11) by measuring the pressure of the colon and small intestine simultaneously with analysis of power spectrum of the electroencephalography (EEG) under mental stress and administration of neostigmine. Stress slightly increased the colonic motility index, reduced the percentage of alpha power, and increased the percentage of beta and theta power of the EEG in the patients with IBS more than in the controls (p < 0.05). The patients with IBS had a longer phase II (p < 0.01) and shorter phase I (p < 0.02) of fasting duodenal motor activity than the controls. Neostigmine (10 micrograms/kg) caused a significant difference in the colonic motility index (p < 0.01) and power spectra of EEG (p < 0.05) in the patients with IBS compared to the controls. Significant positive correlation was detected between colonic motility and power spectral change induced by stress (r = 0.46, p < 0.05) or neostigmine (r = 0.51, p < 0.01). These results suggest that patients with IBS have exaggerated responsivity of the gut and the brain to mental stress and cholinergic stimulation. Moreover, there is a possibility that these exaggerated responses are related.
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PMID:Brain-gut response to stress and cholinergic stimulation in irritable bowel syndrome. A preliminary study. 818 28

Irritable bowel syndrome is widely considered to be associated with disordered gastro-intestinal motility. The evidence for a motor disorder in the colon and small intestine of patients with irritable bowel syndrome is reviewed. Results of myoelectric, motility and transit studies in both the colon and small intestine are inconsistent. Difficulties in interpreting colonic motility have led investigators to address the small intestine as a possible site of dysmotility. An increase in the number of clustered contractions in the proximal small intestine has been reported by some, but not all investigators. Methodological differences as well as patient selection, symptom severity and fluctuation may all contribute to discrepancies between the results of different studies. Motility disturbances may be present which are currently unrecognised due to an inadequate understanding of the propagation of colonic contractions, and of small intestinal contractions during phase II and postprandially. Whether the reported motor disturbances arise locally in the gut or originate from higher centres in the central nervous system has not been established.
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PMID:Intestinal motor function in irritable bowel syndrome. 804 30

Gut motility disorders and altered pain perception were reported in patients with irritable bowel syndrome (IBS). To verify foregut involvement in IBS, we studied 30 patients using esophageal manometry and 24-hr pH monitoring of the distal esophagus. Two subgroups of patients underwent esophageal provocative tests (bethanechol 50 micrograms/kg subcutaneously and esophageal balloon distension test). Twelve healthy volunteers formed a control group. A pain threshold on esophageal distension significantly lower than in healthy subjects (11.5 +/- 1 ml vs 22.2 +/- 1.7 ml, P < 0.01) was found in IBS patients. On the other hand, no differences between patients and controls were detected in lower esophageal sphincter pressure and length, esophageal body motility, or GER pattern; furthermore, bethanechol stimulation elicited similar esophageal body motility changes. Our study could confirm no detectable basal or bethanechol-induced esophageal motility disorders in IBS patients, nor enhanced GER. Esophageal involvement in IBS consists of a lower pain threshold on esophageal distension, possibly reflecting an altered visceral receptor sensitivity or modulation throughout the gut.
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PMID:Altered esophageal pain threshold in irritable bowel syndrome. 809 69

Because unsubstantiated beliefs link hysterectomy and cholecystectomy with bowel function, this study examined all the women who had had these operations in a defined population (79 and 37 respectively, out of 1058) with respect to bowel habits, irritable bowel syndrome symptoms, and whole gut transit time calculated from records of three defecations. Compared with unoperated controls, women after hysterectomy were more likely to consider themselves constipated; they also strained more and admitted more often to bloating and feelings of incomplete evacuation. Their stools tended to be lumpier and, in women over 50 years, transit time was longer. When women treated by cholecystectomy were compared with women having newly discovered, asymptomatic gall stones, they more often described defecation as urgent but had no other detectable differences. In conclusion symptomatic constipation is frequent in women after hysterectomy; after cholecystectomy, bowel habit is not consistently changed but the rectum seems to be more irritable.
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PMID:Bowel function and irritable bowel symptoms after hysterectomy and cholecystectomy--a population based study. 817 64

Disturbances of small bowel motor function are increasingly recognized in clinical practice, either in the setting of an underlying disease that may affect the neuro-hormonal control of gut motility, such as diabetes or scleroderma, or as part of unexplained intestinal dysfunctions such as the irritable bowel syndrome or chronic idiopathic intestinal pseudo-obstruction. In the absence of endoscopic or radiological mucosal disease, it is often clinically helpful to define the motor function of the small bowel to understand the origin of the patient's symptoms. The hydrogen breath test after a lactulose oral load is currently used to measure mouth to caecum transit time. However, the reproducibility of this test is poor, and the range of normal values is wide. Scintigraphic determination of small intestinal transit time overcomes some of the limitations of the hydrogen breath test. This is however a time consuming procedure--up to 10 hrs when the time for acquisition, processing and analysis is included--and the costs prohibit widespread application of the technique. It is further restricted by the exposure to ionising radiation, particularly if repeated evaluations are necessary, for example in drugs trials. Manometry records mechanical activity of the bowel and detects quantitative and qualitative changes of small intestinal motility. As with scintigraphy, high costs and radiation exposure limit its usefulness. The major clinical application of the technique is in the diagnosis of chronic intestinal pseudo-obstruction.
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PMID:[Evaluation of small intestinal motility]. 821 Oct 47

First, it is important to find out whether the patient is complaining of infrequent defaecation, excessive straining at defaecation, abdominal pain or bloating, a general sense of malaise attributed to constipation, soiling, or a combination of more than one symptom. Second, one must decide if there is a definable abnormality as a cause of the symptom(s). Is the colon apparently normal or is its lumen widened (megacolon)? Is the upper gut normal or is there evidence of neuropathy or myopathy? Is the ano-rectum normal or is there evidence of a weak pelvic floor, mucosal prolapse, major rectocele, an internal intussusception or solitary rectal ulcer? Is there any systemic component such as hypothyroidism, hypercalcaemia, neurological or psychiatric disorder or relevant drug therapy? Choice of treatment will depend on this clinical evaluation. The range of treatments available is: Reassurance and stop current treatment: Patients with a bowel obsession may take laxatives or rectal preparations regularly without need. Increase dietary fibre: Most cases of 'simple' constipation respond to increased dietary fibre, possibly with an added supplement of natural bran. Toilet training and altered routine of life: Young people particularly may need to recognise the call to stool and alter their daily routine to permit and encourage regular defaecation. Medicinal bulking agent: Ispaghula, methyl cellulose, concentrated wheat germ or bran, and similar preparations are useful when patients with a normal colon find it difficult to take adequate dietary fibre. These preparations increase the bulk of stool and soften its consistency. They may be useful for those patients with the constipated form of irritable bowel syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Clinical management of constipation. 823 32

When no identifiable organic cause for colonic symptoms can be found, it is easy for the busy clinician to label the patient neurotic. It is evident that many of these "functional" disorders do reflect an underlying motility disorder, although our understanding is far from clear. However, currently, patients with severe constipation are evaluated in a much more rational manner and, as a consequence, are offered a reasonable therapeutic approach that can be predicted to have a good chance for success. We can hope that as our understanding of irritable bowel syndrome is strengthened, treatment will become more efficacious than the unproved and costly medications that are in use currently. Until dietary modification becomes commonplace, it is unlikely that the incidence of diverticular disease or its complications will change. Already, our understanding of ileus has allowed us to realize the benefits of laparoscopic surgery, and as our knowledge of the various gut hormones and the inhibitory role that some play in intestinal motility grows, ileus, and its resulting prolongation of hospital stay, may become less problematic.
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PMID:Pathophysiology of colonic motility disorders. 824 36

Major advances have been made in the understanding of the pathophysiology of stress-related alteration of gut function. A wealth of information indicates that CRF is involved in the central mechanisms by which stress inhibits gastric emptying while stimulating colonic motor function. CRF acts in the PVN to trigger both the inhibition of gastric emptying and the stimulation of colonic motor function in response to stress, in addition to previously established endocrine and behavioral responses. Preliminary evidence exists that CRF acts in the locus coeruleus to induce a selective stimulation of colonic transit without influencing gastric emptying. The central actions of CRF to alter gastric and colonic motor function are conveyed by autonomic pathways and are unrelated to the associated stimulation of pituitary hormone secretion. The demonstration that central CRF plays a role in mediating gastric stasis resulting from surgery, peritonitis or high levels of central interleukin-1 provides new insight into the mechanisms involved in gastric ileus induced postoperatively or by infectious disease. Likewise, the demonstration that CRF in the PVN and locus coeruleus induce the anxiogenic and colonic motor responses to stress and that colonic distention activates neurons in the locus coeruleus opens new avenues for the understanding of the pathogenesis of a subset of IBS patients with colonic hypersensitivity associated with psychopathological disturbance and diarrhea-predominant symptoms.
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PMID:Role of CRF in stress-related alterations of gastric and colonic motor function. 825 13


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