Irritable Bowel Syndrome Flashcards
Definition
A chronic, relapsing, and often lifelong disorder
Affects lower GI tract for at least 3 months
No discernable structural or biochemical cause = considered functional
Epidemiology
Young adults = 20-30 years
- prevalence decreases with increasing age
Female
Risk factors
Family history
GI infection/inflammation
Dietary factors - alcohol, caffeine, spicy, fatty foods
Psychosocial factors: anxiety, depression, PTSD, previous physical or sexual abuse
Drugs: antibiotics
Pathophysiology
A mixture of group abdominal symptoms for which no organic cause can be found = functional bowel disorder:
- Disorder of intestinal motility: short chain carbs can act as solutes that draw in more water into lumen - wall stretchers = pain
- Enhanced visceral perception: hypersensitivity: sensory nerve endings have strong response to stimuli when bowel stretches after a meal = more pain
- Dysfunction of brain gut axis
- Microbial dysbiosis (imbalance)
Pain is often relieved by defecation
3 types:
- IBS - C
- IBS - D
- IBS - M
Diagnostic criteria
Abdominal pain/discomfort associated with 2+ of:
- Altered stool passage (straining, urgency, incomplete evacuation)
- relieved by defecation
- altered stool form
- altered bowel frequency, constipation then diarrhoea
- passage of mucus per rectum
- symptoms worse after eating
- abdominal bloating, distension, or hardness
Symptoms
Following symptoms for at least 6 months: (ABC)
- Abdominal pain
- Bloating
- Change in bowel habit
Mucus in rectum + stool
Worsening of symptoms after food
IBS = multisystem disorder…
Painful periods
Bladder symptoms:
- frequency
- urgency
- nocturia
- incomplete emptying
Back pain
Joint hypermobility
Fatigue
Nausea
Exacerbations
Stress
Menstruation
Gastroenteritis
Microbial dysbiosis
Having a high FODMAPS diet (high in short-chain cabs)
Diagnosis
Diagnosis of exclusion
- FBC = anaemia = non IBS
- ESR + CRP = inflammation = non IBS
- Anti=tTG/EMA = coeliac disease
- Stool testing = faecal calprotectin = IBD not IBS
- Colonoscopy = IBD, colorectal cancer ruled out
- X - ray = rule out small and large bowel obstruction
Treatment
FIRST LINE = Dietary modification
- regular meals
- fluids
- avoid caffeinated, alcoholic, fizzy drinks,
- avoid fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPS)
- avoid stress/anxiety/depression
SECOND LINE = (moderate IBS)
- pain/bloating = antispazmodics = mebevabine, buscopan, ranetidine
- constipation = bulk forming laxatives = fybogel (ispaghula husk), senna
- if severe constipation symptoms persist for atleast 12 months = LINACLOTIDE
- diarrhoea = loperamide
severe = TCA = amitriptyline
