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Irritable Bowel Syndrome
Aka: Irritable Bowel Syndrome, Functional Chronic Diarrhea
- Epidemiology
- Prevalence
- Overall in U.S.: 5-10%
- Lifetime Prevalence: 10-22%
- Slightly more common in women (1.5 fold increased risk over men)
- Prevalence for elderly same as for young (however, peak time of diagnosis at 20-39 years old)
- Most common condition seen by Gastroenterologists
- Pathophysiology
- Organic factors
- Gastrointestinal hypersensitivity
- Altered motility
- Neurohormonal factors
- Mucosal barrier dysfunction
- Provoked by psychosocial risk factors
- Prior physical or sexual abuse significantly increases risk
- Severe Gastroenteritis episode may be associated (Odds Ratio 5.9)
- Antibiotics (Rifamaxin, Neomycin) have reduced symptoms in some cases
- Familial association
- Risk increases 3 fold with Family History of Irritable Bowel Syndrome
- Associated Conditions
- Gastroesophageal Reflux Disease
- Dysphagia
- Globus Hystericus
- Fatigue
- Non-cardiac Chest Pain
- Urologic dysfunction
- Gynecologic disease (e.g. Chronic Pelvic Pain)
- Fibromyalgia
- Chronic Fatigue Syndrome
- Temperomandibular joint syndrome
- Food Allergy
- Low-fiber diet
- Risk Factors: Psychosocial
- Anxiety Disorder
- Major Depression
- Somatization Disorder
- Sexual abuse or physical abuse
- Stressful life events
- Substance Abuse
- Types
- Alternating Diarrhea and Constipation
- Nervous Diarrhea
- Predominant Constipation
- Upper abdominal bloating and discomfort
- Symptoms
- Altered bowel habits
- Diarrhea
- Constipation
- Scybalous stools (hard, pellet-like stools)
- Mucus per rectum (40% of cases)
- Incomplete evacuation sensation (69% of cases)
- Recurrent and Chronic Abdominal Pain (73% of cases)
- Upper abdominal discomfort after eating
- Left Lower Quadrant Abdominal Pain
- Right Lower Quadrant Abdominal Pain
- Abdominal Pain relieved with Defecation (52% of cases)
- Gaseousness
- Excessive Flatulence or Eructation
- Normal patients experience about 13 farts per day
- Abdominal distention (32% of cases)
- Nausea or Vomiting
- References
- Ford (2008) JAMA 300(15): 1793-805
- Diagnosis: Rome III Criteria
- Abdominal symptoms persistent or recurrent for 6 months or more
- Symptoms occur on at least three days per month for at least 3 months
- Abdominal Pain, bloating or discomfort
- Marked change in bowel habits
- Change in stool frequency
- Change in stool consistency (Constipation or Diarrhea)
- Altered stool passage
- Straining for normal consistency stool
- Urgency of Defecation
- Incomplete evacuation
- Two or more below
- Pain relieved with Defecation
- Onset of pain is related to a change in frequency of stool
- Onset of pain is related to a change in appearance of stool
- Diagnosis: Manning Criteria
- Onset of pain linked to more frequent Bowel Movements
- Looser stools associated with onset of pain
- Pain relieved by stool passage
- Noticeable abdominal bloating
- Sensation of incomplete evacuation more than 25% of the time
- Diarrhea with mucus more than 25% of the time
- Red Flags: Symptoms and signs suggestive of other diagnosis
- Nighttime Diarrhea
- Nocturnal Stool Incontinence
- Nocturnal awakening due to abdominal discomfort
- Abdominal Pain that interferes with normal sleep
- Visible or occult blood in stool
- Weight loss
- Recurrent Fever
- Family History of Colon Cancer
- Family History of Inflammatory Bowel Disease
- Elderly
- Diarrhea without pain suggests alternative diagnosis
- Laboratory abnormality
- Leukocytosis
- Anemia
- Increased Erythrocyte Sedimentation Rate (ESR)
- Differential Diagnosis
- Colonic Adenocarcinoma
- Inflammatory Bowel Disease
- Ulcerative Colitis
- Crohn's Disease
- Abdominal Angina (Ischemic Colitis)
- Pseudo-obstruction (Diabetes Mellitus, Scleroderma)
- Intermittent sigmoid Volvulus
- Toxic Megacolon or bacterial overgrowth syndrome
- Endocrine causes
- Hypothyroidism or Hyperthyroidism
- Diabetes Mellitus
- Addison's Disease
- Malabsorption
- Celiac Sprue (strongly consider if Diarrhea with red flags)
- Lactose Intolerance
- Pancreatic insufficiency
- Giardiasis
- Endometriosis
- Psychiatric illness
- Depression
- Somatization
- Anxiety Disorder or Panic Disorder
- Medications
- Laxatives
- Constipating medications
- Evaluation
- General
- Avoid a piecemeal work-up
- Perform a complete evaluation the first time
- Avoid over-investigation
- Irritable bowel is no longer diagnosis of exclusion
- Diagnostic criteria above are sufficient to treat
- Lab and imaging are typically low yield in cases otherwise suggestive of Irritable Bowel Syndrome
- Indications for full evaluation and Gastroenterology
- Red flags present (see above) or
- Onset over age 50 years
- Careful History
- History of Gastrointestinal Symptoms
- Family History of gastrointestinal disease
- Marital History
- Sexual Abuse (strong correlation)
- Reasonable exam
- Thorough abdominal examination
- Also focus on possible endocrine causes
- Look for Food Intolerance (consider diet diary)
- Lactose Intolerance
- Sorbitol
- Wheat (Gluten Sensitive Enteropathy)
- Labs: Initial, based on predominant symptom
- Constipation dominant
- Complete Blood Count (CBC)
- Serum Electrolytes or Chemistry panel (chem8)
- Thyroid Stimulating Hormone (TSH)
- Diarrhea predominant
- Evaluation in absence of negative red flags
- Complete Blood Count (CBC)
- Tissue transglutaminase IgA for Celiac Sprue
- Other tests to consider if indicated by history (previously recommended as part of standard default protocol)
- Stool Ova and Parasites
- Fecal Leukocytes
- Serum Electrolytes or chemistry panel
- Thyroid Stimulating Hormone (TSH)
- Erythrocyte Sedimentation Rate (ESR) or C-Reactive Protein (C-RP)
- Pain Dominant
- Complete Blood Count (CBC)
- Reference
- Fass (2001) Arch Intern Med 161:2081-8
- Diagnostic studies
- Colonoscopy of Flexible Sigmoidoscopy
- More uncomfortable in Irritable Bowel Syndrome
- Not absolutely indicated if remainder of evaluation suggests Irritable Bowel Syndrome
- Consider if red flags or age over 50 years
- Consider additional studies as indicated (to evaluate differential diagnosis)
- CT Abdomen with contrast
- Right upper quadrant Ultrasound
- Upper GI Study
- Barium Enema
- Management: General Measure
- See the patient frequently
- Maintain a strong doctor-patient relationship
- Offer frequent reassurance
- Identify and treat emotional stressors
- Answer patients questions in unhurried environment
- Do not downplay symptoms as psychiatric
- Irritable Bowel is a real functional bowel problem
- Explain physiology and absence of serious illness
- Reduce stressors
- Teach relaxation techniques
- Teach coping mechanisms for chronic illness
- Exercise
- Consider Probiotics
- Bifidobacterium bifidum MIMBb75
- Decreases overall irritable bowel symptoms
- Guglielmetti (2011) Aliment Pharmacol Ther 33(10): 1123-32
- General Diet recommendations
- Get adequate fluid intake (>64 ounces/day)
- Bulk agents (gradually increase)
- Metamucil
- Citrucel
- High fiber-bran
- Avoid FODMAPS (Fementable Oligo- di and mono saccharides and polyols)
- Avoid fructose (e.g. apples, pears, high fructose corn syrup)
- Avoid Fructans (fructooligosaccharides, inulins, levans - e.g. high fiber bars)
- Avoid Lactose (consider challenge with quart of skim milk)
- Avoid Polyols (sugar Alcohols: Sorbitol, xylitol, mannitol, malitol
- Avoid Galactooligosaccharides (e.g. brussel sprouts, onions)
- Consider avoiding other provocative agents
- Consider Elimination Diet (although no evidence to support this)
- Avoid Caffeine
- Avoid Alcohol
- Avoid Legumes and other gas producing foods (see FODMAPS above)
- Avoid Artificial Sweeteners and carbonated beverages (see Polyols above)
- Avoid Fatty meals
- Corn, wheat and citrus may also exacerbate Irritable Bowel Syndrome
- Some fiber can also exacerbate symptoms
- Avoid Provocative or addictive medications
- Stimulant Laxatives (except brief use)
- Correctol
- Dulcolax
- Cascara
- Sedatives or Tranquilizers (Benzodiazepines)
- Narcotics
- Management: Symptom specific medications
- Diarrhea
- Consider eliminating lactose, Caffeine from diet
- Exclude Gluten Sensitive Enteropathy as cause
- Cholestyramine 4 grams qhs to 6 times daily
- Loperamide (Imodium) 2-4 mg qid prn
- Before meals
- As needed in stressful social situations
- Ondansetron (Serotonin antagonist)
- Reduces rapid transit
- Alosetron (Lotronex)
- Risk of Constipation and Ischemic Colitis
- Iatrogenic deaths have occured
- Black box warning: Signed informed consent needed
- FDA controlled prescriptions only for women with IBS with Diarrhea
- Requires special informed consent and must be part of a prescriber program
- Dose: 1 mg daily (may advance to bid)
- Peppermint
- Pittler (1998) Am J Gastroenterol 93:1131-5
- Comorbid Mood Disorders
- Major Depression
- SSRI Medications or other Antidepressants
- Anxiety
- Buspar
- Amitriptyline (Elavil)
- Pain dominant symptoms
- Chronic Pain
- Amitriptyline (Elavil) 25 mg qhs
- Desipramine (Norpramin) 50 mg tid
- Tegaserod (Zelnorm)
- Nyhlin (2004) Scand J Gastroenterol 39:119-26
- SSRI medications may be effective as adjunct (e.g. Zoloft)
- Tabas (2004) Am J Gastroenterol 99:914-20
- Post-prandial pain: Anticholinergic
- Avoid chronic, frequent use
- Trial for 2 weeks and stop if no effect
- Dicyclomine (Bentyl) 10-20 mg, 15 min before meal
- Hyoscyamine (Levsin) 0.125 to 0.25 mg before meal
- Constipation
- Use gastro-colic response
- Wake-up, eat breakfast and anticipate stool in AM
- First line: Bulk agents (e.g. Fiber, Psyllium, bran)
- Titrate to 20-30 grams per day
- Risk of bloating initially (requires adequate hydration)
- Evidence to support is lacking, but remains a central tool in IBS management
- Second line (use at bedtime for AM stool)
- Improves stool frequency, but may not alter Abdominal Pain
- Osmotic agents
- Lactulose 1-2 teaspoons at bedtime
- Polyethylene glycol solution 8 ounces at bedtime
- Milk of Magnesia 1-2 tablespoons at bedtime
- Miralax
- Consider Stimulant Laxatives if osmotic agents fail
- Senna or Cascara
- Bisacodyl
- Third line (prescription agents that increase GI transit and intestinal fluid)
- Amitiza (Lubiprostone)
- Drossman (2009) Aliment Pharmacol Ther 29(3): 329-41
- Linzess (Linaclotide)
- Expensive ($7 per pill) for minimal efficacy (NNT 5-8) for decreased pain
- (2012) Prescr Lett 19(12): 68-9
- Restricted Use agent (emergency use only due to risk)
- Tegaserod (Zelnorm): 5-HT4 agonist
- Dose: 6 mg bid 30 minutes before meals
- Cardiovascular event risk prompted removal from U.S. market in 2007
- Other agents potentially useful
- Guar-Gum
- Parisi (2002) Dig Dis Sci 47:1696-704
- Peppermint
- Pittler (1998) Am J Gastroenterol 93:1131-5
- Loxiglumide (cholecystokinin-A receptor antagonist)
- Excessive flatus (gas)
- Simethicone 40 to 125 mg up to qid
- Beta-galactosidase (Beano)
- Resources
- International Foundation for Functional GI Disorders
- http://www.iffgd.org
- American College of Gastroenterology
- http://www.ACG.GI.org
- Mind-Body Digestive Center
- http://www.mindbodydigestive.com
- References
- Camilleri (2000) Gastroenterology 120:652-68
- Camilleri (1999) Am J Med 107(5A):27F-32S
- Chang (2006) Curr Treat Options Gastroenterol 9(4):314-23
- Drossman (1999) Am J Med 107(5A):41S-50S
- Hammer (1999) Am J Med 107(5A):5S-11S
- Heymann-Monnikes (2000) Am J Gastroenterol 95:981-4
- Holten (2003) Am Fam Physician 67(10):2157-62
- Jailwala (2000) Ann Intern Med 133:136-47
- Mertz (2003) N Engl J Med 349:2136-46
- Naliboff (1999) Curr Rev Pain 3:144-52
- Ringel (2001) Annu Rev Med 52:319-38
- Viera (2002) Am Fam Physician 66:1867-80
- Wilkins (2012) Am Fam Physician 86(5): 419-26