_bowel syndrome （ibs） shanyar肠易激综合征（ibs） 课件

IRRITABLE BOWEL SYNDROME (IBS) Dr. Mohamed Shekhani MBChB-CABM-FRCP IBS: Epidemiology A common disorder, with a 7% prevalence . Women are 1.5 times more likely to be affected than men, most commonly between ages 20-40 years. Onset after the age of 50 years is uncommon. IBS:Pathophysiology Not well understood,may vary depending on the subtype i.e patients with constipation need imaging to rule out a mechanical obstruction. In patients with IBS with diarrhea who undergo colonoscopy, biopsies of the colon should be done to evaluate for microscopic colitis, particularly if there is suggestion of a secretory diarrhea. IBS: treatmet Depends on a patients predominant symptoms. Although patients often link diet to symptoms, no clear data support elimination diets or food allergy testing, but if individual patients identify clear food triggers, these can be eliminated or reduced. IBS: treatmet for CP-IBS Bulking agents, specially fiber in the form of psyllium hydrophilic mucilloid (ispaghula husk) although laxatives appear to improve frequency of bowel movements in those with constipation, it remains unclear whether they have any effect on pain. Osmotic laxatives such as milk of magnesia as well as nonabsorbable polyethylene glycol, sorbitol,lactulose are generally believed to be safer than stimulant laxatives, but they may be associated with bloating / flatulence; so senna / bisacodyl may be appropriate for intermittent use for constipated patients. Tegaserod, a 5-HT4 (serotonin) agonist had been previously approved to treat IBS with constipation in women potential serious but uncommon side effects include both severe constipation tricyclics also have an anticholinergic effect & may induce constipation. Smaller doses than are used in the treatment of depression are generally recommended. Comorbid depression may best be treated with a SSRI. Psychosocial stressors should also be addressed. IBS: Bacterial overgrowth trt While the link between small intestinal bacterial overgrowth & IBS remains unclear, the short-term (10-14 days) use of the nonabsorbed antibiotic rifaximin at doses between 1000-1200 mg/day has demonstrated improvement in global IBS symptoms, bloating &diarrhea in IBS&diarrhea. Other antibiotics such as neomycin may be effective. The efficacy of probiotics is yet to be determined adequately. Antibiotic /probiotic therapy has been used because bacterial overgrowth has been implicated, possibly through abnormal motility or as a sequela of postinfectious IBS. Rifaximin has been effective in relieving symptoms i