Irritable Bowel Syndrome

IRRITABLE BOWEL SYNDROME • • • • • • •

Most commonly diagnosed gastrointestinal condition. The prevalence of IBS - 10 to 15 percent. 2:1 female predominance 25 to 50 percent of all referrals to gastroenterologists 12% of primary care provider visits The second highest cause of work absenteeism after the common cold increased health care costs, with some studies suggesting annual direct and indirect costs of up to $30 billion

The etiology of IBS is unknown, but various hypotheses have been generated including abnormal gut motility, bacterial overgrowth, food allergies, altered visceral sensitivity, infectious triggers, hormonal disruption, and disorders of the serotonin reuptake transport system. MANNING CRITERIA Pain relieved with defecation More frequent stools at the onset of pain Looser stools at the onset of pain Visible abdominal distention Passage of mucus Sensation of incomplete evacuation ROME III Recurrent abdominal pain or discomfort for at least three days per month in the previous three months with symptom onset in six months prior to diagnosis with two or more of the following: � Pain relieved with defecation, and/or � Onset associated with a change in frequency of stool, and/or � Onset associated with a change in form (appearance) of stool SUBTYPES - IBS with constipation, IBS with diarrhea, Mixed IBS, Unsubtyped Patients with typical IBS symptoms and no alarm features require few tests beyond the history and exam. Consider obtaining a CBC and chemistry panel in most patients, but reserve thyroid testing, extensive stool testing (including O & P ), and other blood work (such as antibody studies for celiac sprue) for patients with findings that are concerning for a specific alternate diagnosis.

TREATMENT Therapeutic relationship Dietary modification Behavioral treatments may be considered for motivated patients who associate symptoms with stressors, although their benefits remain controversial Eg: Hypnosis, biofeedback, and psychotherapy Antispasmodics - hyoscine, cimetropium, pinaverium, and peppermint oil Antidepressants – TCA, SSRI Antidiarrheal agents – Loperamide 5-HT-3 receptor antagonists (alosetron (Lotronex), cilansetron, ondansetron and granisetron ) - diarrhea predominant cases 5-HT-3 receptor agonists – Tegaserod (Zelnorm) has cardiovascular side-effects Lubiprostone - locally acting chloride channel activator in IBS-C