irritable bowel syndrome - general medicine

1. RAHNA
66

2.  DEFINITION
 EPIDEMOLOGY
 ETIOPATHOGENESIS
 CLINICAL FEATURES
 DIAGNOSIS
 RED FLAG SIGNS
 INVESTIGATIONS
 TREATMENT

3. It is a functional bowel disorder characterized by
abdominal pain or discomfort and altered bowel
movements in the absence of detectable structural
abnormalities
Chronic, recurrent ,relapsing and often lifelong
Often overlap with other functional disorders like
fibromyalgia, headache, backache and genitourinary
symptoms

4.  Prevalence : 1-20% worldwide (10% to 20% - US and Europe
5% - Asian countries)
 Incidence : 1-2% per year
 2-3 times more common in women
 Most patients have their first symptoms before 45 years of age
INDIA
 Prevalence is 4-8%
 More common in men

5.  Etiology is uncertain and maybe multifactorial
 Pathogenesis in IBS is poorly understood
GI Motor Abnormalities
Visceral Hypersensitivity
Brain gut axis Dysregulation
Abnormal Psychological features

6. Postinfectious IBS
Risk factors- young females,prololged duration of initial illness,
toxicity of infecting bacterial strain
Microbes involved in initial infection – Campylobacter
,salmonella and shigella
Immune activation and low grade mucosal inflammation
Altered gut flora
Abnormal serotonin pathways
 Serotonin plays an important role in regulation of GI motility
and visceral perception
 IBS –D patients show increased 5HT containing
enterochromaffin cells in colon

7. • Abdominal pain
and discomfort
• Altered bowel
habits
• Gas and flatulence
• Upper GI
symptoms

8. Abdominal pain or discomfort
 A prerequisite for the diagnosis of IBS
 It is episodic and crampy & highly variable in intensity and
location
 Sleep deprivation and malnutrition is uncommon
 Pain exacerbated by eating and emotional stress and improved by
passing stools or flatus
 In females symptoms worsen during premenstrual and menstrual
phases

9. Altered bowel habits-
 Alteration in bowel habits most consistent clinical feature
 Most common pattern is constipation alternating with diarrhea
 At first constipation is episodic but later becomes continuous and
unresponsive to laxatives
 Stools are usually hard with narrowed caliber
 Sense of incomplete evacuation
 Pts. with diarrhea have a stool volume <200ml and maybe associated
with passage of mucus but not blood
 Nocturnal diarrhea not seen

10. Gas and flatulence-
 Pts complain of abdominal distention and increased belching or
flatulence
Upper GI symptoms-
 25-50% complain of dyspepsia, heartburn, nausea and vomiting
 Indian patients have more of upper GI symptoms

11.  IBS-D (Diarrhoea predominant)
 IBS-C (Constipation predominant)
 IBS-M (Mixed diarrhoea and constipation)
 Usefulness of subtypes debatable
 Within 1 yr 75% change subtypes & 29% switch between IBS-C and IBS-D

12.  No clear diagnostic markers exist for IBS
 So diagnosis depends on positive clinical features and ruling out
organic diseases by careful clinical examination and investigations
 Diagnosis can be made confidently in most patients using
Rome III criteria + absence of red flag signs + supportive symptoms
which include defecation straining, urgency or a feeling of incomplete
bowel movement ,passing mucus and bloating

13.  Sensitivity 17%
 Specificity 95%

14. RED FLAG
 Unintentional and unexplained wt. loss
 Rectal bleeding
 Family h/o bowel/ovarian cancer
 A change in bowel habit to loose and/or more frequent stools persisting for more
than 6 wks in a person aged over 60yrs.
 Anemia
 Abdominal masses
 Rectal masses
 Inflammatory markers for IBD

15. To rule out organic causes
 CBC
 ESR
 CRP
 Stool examination for ova and parasites
 Antibodies for Coeliac Disease
 Hydrogen breath test
 Sigmoidoscopy when more than 50 years/ red flag signs present
 Younger individual with mild symptoms – minimal diagnostic evaluation,
 Older – undergo more thorough evaluations

16.  IBD
 COLORECTAL CANCER
 COLONIC TB
 FRUCTOS/LACTOSE INTOLERENCE’
 CELIAC SPRUE
 Endocrinopathies- HYPOTHYROIDISM ,HYPERTHYROIDUSM
 INFECTIOUS COLITIS
 ACUTE INTERMITTENT PORPHYRIA and LEAD POISONING
 PHYCOLOGICAL –ANXIETY,DEPRESSION

17.  Patient education and counselling
 Dietary alteration
 Pharmacotherapy
 Psychotherapy

18.  Reassuring the patient is the most successful form of treatment for
IBS
 Many are concerned that they have developed cancer – more anxiety
-more colonic symptoms
 Explain functional nature of disorder and how to avoid obvious food
precipitants
 Emphasise on expected chronicity of symptoms with periodic
exacerbations

19.  Eliminate food stuffs that appear to produce symptoms
 Consume high fibre diet – IBS-C
 Exclude wheat ,diary and gluten –Pain and bloating
 Avoid legumes and excess dietary fibre - IBS-D
 Diet low in FODMAPs
(Fermentable Oligosaccharides, Disaccharides, Monosaccharides And
Polyols)
 FODMAPs areshort chain carbs poorly absorbed in small intestine and
fermented by bacteria in colon to produce gas

21. Antidiarrheal agents
 Delay faecal transit , increase colonic segmentaion contractions and reduce rectal
perception
Serotonin receptor agonist and antagonist
 5 HT3 receptor agonist –5 HT release increases secretions and reduces GI
transit time and cause constipation and hence useful in IBS-D. Eg:- Alosetron
 s/e-Causes ischemic colitis and severe constipation
 5 HT4 agonist – are prokinetic eg Tegaserod- Suspended due to CVS events.

22. Stool bulking agents
 Fibre speeds up colonic transit and prevent excessive hydration and
dehydration of stool
Chloride channel activators
 Chloride secretion induce passive movement of Na and water into bowel lumen
and improve bowel function
Guanylate Cyclase-C Agonist
 Activation of GC-C generates cGMP which triggers secretion of fluid, sodium
and bicarbonate

23.  Antidepressant drugs
 TCAs reduce visceral hypersensitivity
 Their antimuscarinic effects cause constipation. Useful in IBS-D
 SSRIs are secretagogues and stimulate GI motility. Helpful in IBS-C
Modulation of gut flora- Rifamixin , probiotics
Antispasmodics
 provide temporary relief for painful cramps related to intestinal spasm
 Inhibit gastrocolic reflux and reduce postprandial pain
 s/e –xerostomia, urinary retention ,blurred vision ,drowsiness

24.  Psychological therapy is effective in two thirds of patients with IBS who do not
respond to standard medical treatment
 Cognitive behavioral therapy
 Hypnotherapy
 Dynamic therapy

25.  Chronic relapsing condition with considerable financial burden and
impacts overall quality of life
 At present only symptomatic therapy available
 Drugs don’t alter the clinical course
 Treatment should be tailored to the individual patient and should be a
combination of therapies
 No serious complications
 Haemorrhoids - aggravated by constipation and diarrhoea
 Vitamin and mineral deficiencies – because of avoiding certain foods

26. THANK YOU