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)

Diarrhea "with" bacterial fermentation is characterized by acidic liquid stools containing high amounts of organic acids. Disaccharide malabsorption is the main cause. The mechanism of diarrhea is osmotic, and colonic fermentations reduce diarrhea. It is unlikely that starch malabsorption induces significant diarrhea, whereas a high-fiber diet is responsible for "physiologic" diarrhea. Colonic fermentations increase diarrhea due to organic colitis and the "motor diarrheas". They may be responsible for some intestinal symptoms in patients with irritable bowel syndrome. This does not imply a "hyperfermentative" process due to a hypothetical disturbance of colonic microbial ecology.
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PMID:[Colonic fermentation: physiological review and role in digestive pathology]. 218 79

Hydrogen breath tests (H2 BT) have been used extensively to investigate intestinal disaccharidase deficiencies. A potentially useful test for assessing intestinal absorptive function, the H2 BT with D-xylose (H2 BT-D-xylose), has received scant attention. We report here the results of our investigation of this test in 45 patients. Fifteen patients had proved malabsorption that was due to nontropical sprue in nine, and to lymphoma, Whipple's disease, or giardiasis in the remainder. Nine patients had small-bowel bacterial overgrowth secondary to either postsurgical sequelae or intestinal dysmotility. Twenty-one patients with irritable bowel syndrome and 21 healthy individuals served as control groups. All participants ingested 25 g of D-xylose, and alveolar breath samples were obtained thereafter at 30 min intervals for 5 hr. Breath H2 was measured by chromatography. Basal H2 production, peak change (delta) and area under the curve (AUC) were calculated. Simultaneously, 5-hr urinary excretion of D-xylose was measured by colorimetry and served as the reference test. In healthy individuals, D-xylose ingestion increased H2 production (delta = 5.8 +/- 1.4 ppm, P < 0.001). Changes were similar in patients with the irritable bowel syndrome. In contrast, the increase was of a much greater magnitude in the malabsorption group (delta = 49.9 +/- 7.2 ppm, P < 0.001 vs healthy controls). AUC analysis yielded comparable results. Test performance analysis showed that, in malabsorption the H2 BT-D-xylose had a sensitivity index of 0.86, which was identical to that of the urinary D-xylose test. Specificity was 1 and 0.95, respectively; and predictability 1 and 0.93, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Potential usefulness of hydrogen breath test with D-xylose in clinical management of intestinal malabsorption. 842 44

There is overwhelming evidence that functional gastrointestinal disorders (FGIDs) are associated with specific mechanisms that constitute important targets for personalized treatment. There are specific mechanisms in patients presenting with functional upper gastrointestinal symptoms (UGI Sx). Among patients with UGI Sx, approximately equal proportions (25%) of patients have delayed gastric emptying (GE), reduced gastric accommodation (GA), both impaired GE and GA, or neither, presumably due to increased gastric or duodenal sensitivity. Treatments targeted to the underlying pathophysiology utilize prokinetics, gastric relaxants, or central neuromodulators. Similarly, specific mechanisms in patients presenting with functional lower gastrointestinal symptoms, especially with diarrhea or constipation, are recognized, including at least 30% of patients with functional constipation pelvic floor dyssynergia and 5% has colonic inertia (with neural or interstitial cells of Cajal loss in myenteric plexus); 25% of patients with diarrhea-predominant irritable bowel syndrome (IBSD) has evidence of bile acid diarrhea; and, depending on ethnicity, a varying proportion of patients has disaccharidase deficiency, and less often sucrose-isomaltase deficiency. Among patients with predominant pain or bloating, the role of fermentable oligosaccharides, disaccharides, monosaccharides and polyols should be considered. Personalization is applied through pharmacogenomics related to drug pharmacokinetics, specifically the role of CYP2D6, 2C19 and 3A4 in the use of drugs for treatment of patients with FGIDs. Single mutations or multiple genetic variants are relatively rare, with limited impact to date on the understanding or treatment of FGIDs. The role of mucosal gene expression in FGIDs, particularly in IBS-D, is the subject of ongoing research. In summary, the time for personalization of FGIDs, based on deep phenotyping, is here; pharmacogenomics is relevant in the use of central neuromodulators. There is still unclear impact of the role of genetics in the management of FGIDs.
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PMID:Personalized medicine in functional gastrointestinal disorders: Understanding pathogenesis to increase diagnostic and treatment efficacy. 3088 2

Lactase deficiency can lead to significant symptoms in the pediatric population. To date, few studies have examined the prevalence of enzyme testing-based lactase and other disaccharidase deficiencies (DDs) in pediatric patients undergoing upper endoscopic evaluation. The primary objective of this study was to determine the prevalence of selective lactase and other DDs amongst a large cohort of pediatric patients with and without inflammatory bowel disease (IBD: Crohn's disease and ulcerative colitis) via a chart review of 739 patients who underwent esophago-gastro-dudenoscopy EGD between April 2010 and August 2016. We identified 560 pediatric patients (ages 1-18 years) who underwent mucosal enzyme testing at the time of their EGD. The overall rate of lactase deficiency (LD) was 39%. LD positively correlated with age (p=0.00017), but there was no significant difference between age matched IBD and non-IBD patients (45% vs. 42% p=0.68). Four patients (0.17%) were found to have selective maltase deficiency. No selective sucrase or palatinase deficiency was identified. Statistically significant differences occurred in lactase deficiency amongst patients of different races. In conclusion, lactase deficiency is a relatively common finding in children undergoing EGD though at no increased rate amongst the IBD patient population. Disaccharidase testing should be considered in pediatric patients undergoing EGD.
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PMID:Selective lactase deficiency is common in pediatric patients undergoing upper endoscopy. 3103 35