Guidelines for IBS Management
- Identify alarming red flag features that indicate the need for further investigations and referral.
- Distinguish which aspect of its multi-factorial pathophysiology might prompt the development of IBS in a given patient.
- Initiate treatment, including dietary modifications and pharmacological treatment.
- Advise patients on the prognosis of the condition.
Diagnostic Criteria
Consider IBS when following symptoms for six months:
- Abdominal pain or discomfort
- Bloating
- Change in bowel habit
Diagnostic Criteria
- Rome’s Diagnostic criteria.
- Manning’s Criteria.
Rome’s Diagnostic Criteria
At least 12 weeks history, which need not be consecutive in the last 12 months of abdominal discomfort or pain that has 2 or more of the following:
- Relieved by defecation.
- Onset associated with change in stool frequency.
- Onset associated with change in form of the stool.
Supportive symptoms: Constipation predominant: one or more of
- Bowel movements less than 3 times a week.
- Hard or lumpy stools.
- Straining during a bowel movement.
Diarrhoea predominant: one or more of:
- More than 3 bowel movements per day.
- Loose [mushy] or watery stools.
- Urgency.
General:
- Feeling of incomplete evacuation.
- Passing mucus per rectum.
- Abdominal fullness, bloating or swelling.
Manning’s Criteria
Three or more features should have been present for at least 6 months:
- Pain relieved by defecation.
- Pain onset associated with more frequent stools.
- Looser stools with pain onset.
- Abdominal distension.
- Mucus in the stool.
- A feeling of incomplete evacuation after defecation.
Associated Symptoms
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In people with IBS in OPD:
- 25% have depression.
- 25% have anxiety.
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Patients with IBS symptoms who do not consult doctors have identical psychological health to the general population.
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In one study 70% of women IBS sufferers have dysparunia.
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Stressful life events are associated.
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Compared with controls, people with IBS are less well educated and have poorer general health.
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Women: Men = 3:1.
Onset of IBS Symptoms
- Symptoms usually occur after infection – post-infection, bile salt malabsorption
- Use of antibiotics
- Alteration in immune system
- Emotions, depression, anxiety can affect GIT function
- Psychological stress can increase GIT symptoms
Subtypes
- Diarrhoea predominant.
- Constipation predominant.
- Pain predominant.
Differential Diagnosis
- Inflammatory bowel disease.
- Cancer.
- Diverticulosis.
- Endometriosis.
A positive diagnosis, based on Manning’s criteria may provoke less anxiety than extensive tests.
Examination
- Results should be normal or non-specific.
- Abdomen and rectal examination.
- CBC, CRP.
- No consensus as to whether faecal occult blood (FOBs) or sigmoidoscopy is needed.
Investigations (Not recommended as routine)
- CBC
- ESR
- C-reactive protein (CRP)
- Antibody testing for coeliac disease
- Routine testing for celiac disease should be considered in patients with diarrhea-predominant or mixed presentation IBS.
Investigations (Not confirmatory)
- Ultrasound
- Rigid/flexible sigmoidoscopy
- Colonoscopy; barium enema
- Thyroid function test
- Faecal ova and parasite test
- Faecal occult blood