“Functional” Bowel Disorders

Eamonn M M Quigley MD November 2010

“Functional” Bowel Disorders

• Refer to disorders of gut function where there is no obvious abnormality of structure or morphology– Cause symptoms– Impair Quality of Life– Do NOT imply/equate to

psychological/psychogenic!!

A Sub-Classification

• Defined disorders of function; i.e. motility disorders

• Putative disorders of function; “functional disorders”

SymptomsSymptoms DysfunctionDysfunction PathologyPathology

PathophysiologyPathophysiology

Well-Defined Motility Disorders

Motility Disorders

• Primary– Achalasia– Diffuse Oesophageal Spasm– Gastroparesis– Acute/Chronic Intestinal Pseudo-

obstruction– Megacolon– Hirschsprung’s disease

Achalasia• Non-relaxing LOS

– Drop-out of Inhibitory neurons (NO, VIP)

• Aperistalsis in the oesophageal body

• Causes:– Chagas’ disease– Pseudo-achalasia

• Cancers

– Idiopathic

SymptomsSymptoms DysfunctionDysfunction PathologyPathology

PathophysiologyPathophysiology

Chagas’ Disease

Achalasia - Management

• Muscle relaxants– Ca++ - blockers– Nitrates

• Dilatation– Bougie; transient

benefit only– Balloon forced

dilatation

• Surgery– Heller myotomy

• Botox

Ineffective

Diffuse Oesophageal Spasm

• True idiopathic spasm rare; usually secondary to GORD

• Non-cardiac chest pain

• Treat:– Muscle relaxants– Dilatation– ? Surgery

Pseudoobstruction

• Rare disorders resulting in diffuse motor dysfunction:– Oesophageal dysmotility– Gastroparesis– Small bowel pseudobstruction– Colonic pseudobstruction

• Myopathy or Neuropathy• Congenital or Acquired• Primary or Secondary

– Connective tissue diseases– Muscle disease– Neurologic disorders– Metabolic disorders e.g. Diabetes

Pseudoobstruction

Presents as acute or recurrent “obstruction”:• Small intestine• Colon• Acute e.g acute colonic pseudo- obstruction (acute megacolon)• post-op (Ogilvie’s syndrome)

• Chronic• results in intestinal failure• small intestinal bacterial overgrowth• inability to tolerate p.o. nutrition

SymptomsSymptoms DysfunctionDysfunction PathologyPathology

PathophysiologyPathophysiology

Scleroderma

GeneticsImmunologyGeneticsImmunology

SymptomsSymptoms DysfunctionDysfunction PathologyPathology

PathophysiologyPathophysiology

Neurological Disease:1. Brain Stem TumorNeurological Disease:2. Parkinson’s Disease

DysphagiaNauseaIleusConstipationIncontinence

DysphagiaNauseaIleusConstipationIncontinence

Hirschsprung’s Disease

• Children; rarely presents in adulthood

• Loss of inhibitory neurons

• Genetics understood

• Svenson’s pull-through procedure

SymptomsSymptoms DysfunctionDysfunction PathologyPathology

PathophysiologyPathophysiology

Hirschsprung’s Disease

“Functional” Disorders

• Functional Heartburn• Globus Sensation• Functional Dyspepsia• Irritable Bowel Syndrome• Functional Abdominal pain• Functional Diarrhoea/Constipation

Often overlap; one disorder or a number of discrete disorders

Functional GI Disorders

• Responsible for over 50% of all G.I. Responsible for over 50% of all G.I. Complaints seen by a G.P.!Complaints seen by a G.P.!

How do you make a diagnosis?

• Symptoms• No pathology• No abnormal blood tests• No abnormal X Ray’s

Diagnosis

• By exclusion• Definitive, based on symptoms ( a

consensus approach)

Rome

• Functional Dyspepsia “ A chronic pain or discomfort centred

in the upper abdomen; may be additional symptoms such as fullness, bloating, early satiety, nausea, vomiting”

Rome

• IBS– “ chronic abdominal pain or

discomfort associated with bowel movement; may be additional symptoms such as bloating, distension, constipation, diarrhoea”

IBS

• Abdo Pain +– Urge to b.m.– Relief by b.m.– Alternating diarrhoea and

constipation

• Bloating, distension• Difficult defaecation

Functional Bowel DisordersCause(s)

• Motor Dysfunction• Visceral Hypersensitivity• Low-grade inflammation• Central Perception• Psyche

FD – Pathophysiology; motility

• Gastroparesis • Impaired Fundic Accommodation• Antral Dilatation • Gastric Hypersensitivity • Abnormal Cerebral Perception • Helicobacter Pylori

IBS - Pathophysiology

• Motility• Visceral Hypersensitivity• Central Perception• Inflammation

– Post-infective– Immune activation– Microbiota different

• Psyche

Case History

• 24 year-old female graduate student, volunteers in Africa

• 2000 presented with a 2 year history of abdominal cramps and constipation

– Went on wheat-free diet– Substituted soya for cows milk– Lived in:

» Malawi age 3-10» Malaysia age 14-16

• December 2003– Every 2 weeks: diarrhoea, nausea lasting 2-3 days– Loperamide helped

• April 2004– Anticholinergic, antispasmodic and antidiarrhoeal: some

help• July 2004

Case History

• July 2004• Despite 6 diphenoxylate/day

– Every 3-4 days borborygmi and cramps followed by diarrhoea (b.o. X 5 in a.m.) and urgency

– Took tinidazole for 4 days – no effect– Family history of pernicious anaemia, coeliac

disease and Crohn’s disease

Case History

• April 2009• Intermittent symptoms

– Worse after meals and when stressed

• Has had a number of anti-biotic and anti-parasitic regimes

• No weight loss• Extensive and repeated investigations

– Blood work, gastroscopy, colonoscopy, small bowel x-rays, abdominal imaging

» All negative

Management

• Listen and appreciate– Understand aggravating factors and modify

• Symptomatic– Anti-diarrhoeals– Laxatives– Anti-spasmodics

• Tricyclic anti-depressants (low dose); SSRI’s• Behavioral and psychological therapies

Summary• Motility disorders

– Not common– May cause considerable disability– Based on disorders of intestinal nerve or

muscle or their central connections

• “Functional” disorders– Common– May cause considerable impairment in quality

of life– Pathophysiology not fully understood