Funtional Bowel Disease

Functional Bowel Disorders

Zaryab GhauriBatch E

Definition

Functional bowel disorders are functionalgastrointestinal disorders with symptoms attributable to the middle or lower gastrointestinal tract.

Classification

These include the following:

1.IBS (Irritable Bowel Syndrome)2.Functional bloating3.Functional constipation4.Functional diarrhea5.Unspecified functional bowel disorder

When to label a bowel disorder as

Functional Bowel Disorder…Symptoms must have occurred for the first time > 6 months before the patient presents, and their presence on >3 days a month during the last 3 months.

1.IBS (Irritable bowel Syndrome)

IBS is a functional bowel disorder in which abdominal pain or discomfort is associated with defecation or a change in bowel habit.

IBS (Pathophysiology)

Psychosocial FactorsAltered Gastrointestinal MotilityAbnormal Visceral PerceptionInfection and Allergy

IBS (Clinical Features)

Colicky Abdominal Pain(lower Abdomen relieved by defecation)Abdominal Distention (worsens throughout the day)Altered Bowel HabitDefecation straining or urgencyRectal MucusFeeling of incomplete defecation

IBS (Diagnostic Criteria)Recurrent abdominal pain or discomfort at least >3 days per month in the last >3 months associated with 2 or more of the following:

1. Improvement with defecation

2. Onset associated with a change in frequency of stool

3. Onset associated with a change in form (appearance) of stool

IBS-CInfrequent pellety stools, usually in association with abdominal pain or proctalgia

IBS-DFrequent defecation but produce low volume stools + mucus

Mixed IBS (IBS-M)hard or lumpy stools and loose (mushy) or watery stools

Unsubtyped IBSInsufficient abnormality of stool consistency to meet criteria for IBS-C, D, or M.

IBS(Diagnosis Supporting Features)Symptoms >6monthsPrevious medically unexplained symptomsFrequent Consultation for non-GI problemsStress worsen symptoms

IBS (Associated Problems)Heartburn(Non ulcer dyspepsia)FibromyalgiaChronic Fatigue Syndrome

No weight lossUnremarkable physical Examination but abdominal tenderness may be present.

Tensing the abdominal wall increases local tenderness associated with abdominal wall pain, whereas it lessens visceral tenderness by protecting the abdominal organs (Carnett test).

IBS(Investigations)Few tests are required for patients who have typical IBS symptoms.Full Blood CountFaecal Calprotectin NormalSigmoidoscopy

Patient’s age >50years; Male genderFamily history of Colon CancerWeight Loss AlarmingRectal Bleeding FeaturesAnemiaNocturnal Symptoms

Older Patients+Rectal Bleeding History should undergo Colonoscopy to rule out Malignancy or IBD

In IBS-D to exclude organic GI DiseaseMicroscopic ColitisLactose IntoleranceBile Acid MalabsorptionCoeliac DiseaseThyrotoxicosisParasitic Infection(Stool examination for ova and parasites eg Giardia)

IBS (management)

Reassurance

Elimination of Diets(Lactose exclusion, wheat free diet, excess caffeine intake or artificial sweeteners such as sorbitol)

Symptoms Resolve

If Symptoms persist…

IBS-D Avoid legumes excessive dietary fibersSymptoms Persist Anti Diarrheal Drugs

Loperamide

2-8 mg dailyCodeine Phosphate30-90 mg dailyCholestyramine 1 Sachet daily

Symptoms Persist Amitriptyline 10-25mg atnight

Symptoms Persist Relaxation therapyBiofeedbackHypnotherapy

IBS-C High Roughage Diet

Symptoms Persist Isapghol(Psyllium)Lactulose

Symptoms Persist Relaxation therapyBiofeedbackHypnotherapy

Pain and Bloating Spasmolytic DrugsMebeverinePepperment oilAlverine

Symptoms Persist Amitriptyline 10-25mg at nightProbioticsDietry changes (exclude wheat,Dairy Products)

Symptoms Persist Relaxation therapyBiofeedbackHypnotherapy

2.Functional Bloating

Functional bloating is a recurrent sensation of abdominal distention that may or may not be associated with measurable distention, but is not part of another functional bowel or gastro duodenal disorder.

It is about twice as common in women as men and is often associated with menstruation. Typically, it worsens after meals and throughout the day and improves or disappears overnight.IBS associated.

Both increased intestinal gas accumulation and abnormal gas transit.

Functional Bloating(Symptoms)Diurnal PatternDue to ingestion of specific foodExcessive burping or flatus

Diarrhea, weight loss, or nutritional deficiencyshould prompt investigation for intestinal disease.

Functional Bloating(Diagnostic Criteria)

Must include both of the following:

1. Recurrent feeling of bloating or visible distention

at least 3 days/month in 3 months

2. Insufficient criteria for a diagnosis of functional

dyspepsia, IBS, or other functional GI disorder.

Functional Bloating(Treatment)

Associated gut syndrome such as IBS or constipation is improved.

If bloating is accompanied by diarrhea and worsens after ingesting dairy products, fresh fruits, or juices, further investigation or a dietary exclusion trial is worthwhile.

3.Functional Constipation

Functional constipation is a functional bowel disorder that presents as persistently difficult, infrequent, or seemingly incomplete defecation, which do not meet IBS criteria.Also known as chronic idiopathic constipation.

It is due to colonic inertia or anorectal dyssynergia.Depressed patients may have constipation.

Functional Constipation(Diagnostic Criteria)1. Must include 2 or more of the following:

a. Straining during defecations

b. Lumpy or hard stoolsc. Sensation of incomplete evacuationd. Sensation of anorectal obstruction/blockage

e. Manual maneuvers to facilitate defecations(e.g., support of the pelvic floor)

f. Fewer than 3 defecations per week

2. Loose stools are rarely present without the use

of laxatives

3. There are insufficient criteria for IBS

Functional Constipation(Clinical Evaluation)Patient’s gut symptomsGeneral healthPsychological statusUse of constipating medicationsDietary fiber intakeSigns of medical illnesses (e.g., hypothyroidism) should guide investigation.

Perianal and anal examination to detect fecal impaction, anal stricture, rectal prolapse, mass, or abnormal perineal descent with straining.

Laboratory tests are rarely helpful. Endoscopic evaluation of the colon may be justified for patients 50 with new symptoms or patients with alarm features or a family history of colon cancer.

Functional Constipation(Investigation-Transit studies)

If fiber supplementation fails to help or worsens the constipation, measurements of whole gut transit time may identify cases of anorectal dysfunction or colonic inertia.Using radiopaque markers, measurement of whole gut transit time (primarily colon transit) is inexpensive, simple, and safe. Retention of markers in the proximal or transverse colon suggests colonic dysfunction, and retention in the recto sigmoid area suggests obstructed defecation.

Functional Constipation(Treatment)Physicians should stop or reduce any constipating medication the patient may be taking and treat depression and hypothyroidism when present.

Pharmacologic therapy is not advisable until general and dietary measures are exhausted.

Bulking agents(Psyllium, methyl cellulose and calcium polycarbophil)

Laxatives(Bisacodyl, sodium picosulphate, or sennosides)

4.Functional Diarrhea

Functional diarrhea is a continuous or recurrent syndrome characterized by the passage of loose (mushy) or watery stools without abdominal pain or discomfort.

Functional Diarrhea(Diagnostic Criteria)Loose (mushy) or watery stools without pain

Decreased non-propagating colonic contractions(ring contractions) and increased propagating colonic contractions.Accelerated colonic transit inducible by acute stress.

Functional Diarrhea(Clinical Evaluation)

Dietary history can disclose poorly absorbed carbohydrate intake, such as lactose or “sugar-free” products containing fructose, sorbitol, or mannitol.Alcohol can cause diarrhea by impairing sodium and water absorption from the small bowel.

Physical examination should seek signs of anemia or malnutrition.

An abdominal mass suggests Crohn’s disease in the young patient and cancer in the elderly patient.Rectal examination, colonoscopy, and biopsy can exclude microscopic colitis, and IBD.

Abnormal results of blood or stool tests or other alarm features necessitate further tests. Features of malabsorption (malnutrition, weight loss, non–blood-loss anemia, or electrolyte abnormalities) should provoke the appropriate antibody tests and/or duodenal biopsy for celiac disease. Where relevant, giardiasis and tropical sprue should be excluded.

Barium small bowel radiography may be necessary. Rarely, persistent diarrhea may require tests for bile acid malabsorption or, more practically, a trial of the bile acid-binding resin Colestyramine.

Functional Diarrhea(Treatment)Reassurance is important.Restriction of foods, such as those containing sorbitol or caffeine, which seem provocative, may help.

Antidiarrheal therapy (e.g., diphenoxylate or Loperamide) is usually effective, especially if taken prophylacticaly, such as before meals.

Cholestyramine, an ion-exchange resin that binds bile acids and renders them biologically inactive, isoccasionally very effective.

The prognosis of functional diarrhea is uncertain, but it is often self-limited

5.Unspecified Functional Bowel

DisordersIndividual symptoms discussed in the previous sectionsare very common in the population. These occasionallylead to medical consultation, yet are unaccompanied byother symptoms that satisfy criteria for a syndrome. Suchsymptoms are best classified as unspecified.

Unspecified Functional Bowel DisorderBowel symptoms not attributable to an organicetiology that do not meet criteria for the previously defined categories.

Thank You

References

Davidson

http://www.fascrs.org/physicians/education/core_subjects/2005/functional_bowel_disorders/

http://www.romecriteria.org/

http://www.medscape.com/viewarticle/717346_3