IBD Flashcards
What is IBD made up of?
Crohn’s disease
Ulcerative Colitis
Define IBD
Chronic
Idiopathic
Relapsing and remitting
Inflammatory disorders of the GI tract
Which parts of the body does Crohn’s affect?
Anywhere between mouth and anus
Which parts of the body does ulcerative colitis affect?
Large intestine only
What should IBD not be confused with?
IBS - much less acute and dangerous! much more common!
Where is IBD prevalent in?
Increase in Europe and higher latitudes
Argentina
Rise in newly industrialised countries
NOD 2 gene
Protein which helps immune cells in body detect invading pathogens
Autophagy
Another way to protect against invading pathogens
Purpose of epithelial barrier
Separates microbiota in gut from immune system
If not separated = profound inflammatory reaction = destruction of bowel wall, ulcers
Genetic cause of IBD
Mutations/changes in 100s of genes which protect body against invading pathogens
e.g. NOD2, autophagy
Environmental factors affecting IBD
Physical activity Appendectomy - protective in UC Smoking Stress Vitamin D/UV exposure is protective Hygiene Diet Sleep Medications Microbiome Genetic susceptibility
Hygiene Hypothesis
Large decline in infectious diseases = TB, hep A, RF etc.
But large increase in immune mediated disorders = RA, asthma, T1D, MS
Smoking link with Crohn’s
Accelerates progression of Crohn’s
Less likely to respond to treatment
Cessation Is an effective treatment
Smoking link with UC
Onset follow smoking cessation
Nicotine patches as effective as 5ASA (but badly tolerated unless you are a smoker)
Which drugs can initiate a relapse in IBD?
NSAIDs
Oral contraceptive pull = Crohns
Opiods (loperamide, codeine) - provoke colonic dilatation in acute severe UC
What diet is good at treating Crohns?
Elemental/polymeric liquid diet
Foods badly affecting IBD
High animal fat diet
Low fibre intake
Emulsifiers and thickeners
May alter gut microbiome
Link between physical activity and IBD
Regular active exercise reduced risk of
- developing Crohns but not UC
- relapse of Crohns and possibly UC
What type of people are more likely to get UC?
White people Men to women equal 20-40 year olds Second peak >60 Higher rate of monozygotic twins
4 sites of UC
Proctitis (rectum)
Proctosigmoiditis
Left sided colitis (all the `way up to splenic flexure)
Pancolitis (all the way around)
In which UC site are different drug administration methods used?
Proctitis - suppositories
Left sided colitis - enemas
Whole colon - oral therapy
What anatomy is UC limited to?
Colon and rectum only
What is the most common site in UC
Almost always rectum with variable proximal extent
Where is there inflammation in UC
Lamina propria
How do patients with UC present?
Urgent diarrhoea Bloody stools Fatigue (all immune mediated disease) Weight loss Cancer (rare) Extra-intestinal manifestations
What is the hallmark of UC?
Diarrhoea
What extra-manifestations are there in IBD?
Mouth - ulcerations Eyes - uveitis Joints - Arthritis/arthropathy/RA Skin - erythema nodosum shins/feet, pyoderma gangrenosum Perianal disease
What is perianal disease much more common in?
Crohns!! rather than UC
What are the signs of UC?
tender abdomen - LIF generally mild Pallor tachycardia leukonychia - malnutrition extra-intestinal manifestations
Ix of UC
Bloods - anaemia microcytic - low ferritin - low albumin - raised inflammatory markers = CRP, ESR< thrombocytosis, faecal calprotectin - MC&S - OC&P (parasites) - Plain AXR Endoscopy - gold standard
What is faecal calprotectin?
Inflammatory marker expressed by immune cells in lining of gut wall particularly neutrophils that you can detect in stool
Good way to differentiate between IBS and IBD
What are you looking for on an AXR?
Toxic megacolon
Pancolitis severe disease shows this
Dilation of large intestine
UC Histology
Lumen and epithelial layer only affected
Always continuous so will not see areas of unaffected bowel in between
Crypt architecture distortion/twisted
Crypt abscess (neutrophils in crypt)
Crohns histology
Affects whole gut wall unlike UC
Not continuous so will see areas of unaffected areas in between 2 sites of affected bowel
What is a hallmark of chronic inflammation on histology?
Crypt architecture distortion/twisted
Treatment options for UC
Steroids 5-Amino salicylic acid Probiotics Azathioprine Methotrexate Anti-TNF Anti-integrins JAK inhibitors Surgery
Examples of 5-ASA
Sulphasalazine - bone marrow suppression side effect
Mesalazine
Which anti TNFs are used for Tx of UC?
Infliximab - infusion
Adalimumab - SC
Golimumab
Example of anti-integrin
Vedolizumab - blocks alpha4beta7 which binds to MADCAM (adhesion molecule in the blood vessels of gut allowing white cells in to gut
Example of Jak inhibitor
Tofacitinib
Order/protocol of IBD Tx
Vast majority on Mesalazine - oral & topical->
Immunomodulators (azathioprine & 6-mercaptopurine) ->
Anti-TNFs, anti-integrins, Jak inhibitors
What drugs can get you better quickly in UC?
Corticosteroids - IV hydrocortisone, prednisolone, Cortiment MMX
Who is more likely to get Crohn’s?
Higher in Caucasian
1;1 male to female
15-30 yrs
Symptoms of Crohns
DEPENDS WHERE DISEASE IS
- crohns colitis = similar UC symptoms (diarrhoea and urgency)
- terminal ileum = pain colicky post prandially
- altered bowel habits = diarrhoea, obstruction
- PR blood loss
- weight loss more likely than UC as hurts every time you eat
- fistulae and abscesses as affecting whole wall
- oral symptoms
- extra intestinal manifestations
- fatigue
Where is the most common site of Crohns
terminal ileum
Signs of Crohns
- mass
- scars
- stoma
- fistula
- abscess
- malnutrition
- oral ulceration
Natural cycle of Crohns
- starts of inflammatory
- then can get scarring -> structuring/fibrosis/permanent narrowing of bowel
- OR can get penetration
Ix in Crohns
Bloods - anaemic microcytic - low ferritin, folate, B12 - raised inflammatory markers - low albumin Faeces - MC&S - OC&P - faecal calprotectin Plain AXR - loops of small bowel - megacolon Barium Follow Through now rare - strictures - rose thorn ulcers CT be wary of radiation as young patients - terminal ileum thickening - abscess MRI - small bowel - pelvic/perianal sepsis Endoscopy
Crohns Histology
Non caseating granuloma
Regions of unaffected bowel then affected
Giant cells
granulomas
Treatment options for Crohns
Diet
Steroids = prednisolone, budesonide (topical)
5 ASA not used now as uneffective (Pentosa)
Probiotics not that helpful
ABs (cipro, metro allow healing)
Immunosuppressants
Biologicals - Anti-TNF, anti-integrin, anti-IL 12/23
Surgery
Which immunosuppressants are used in Crohns
Azathiopurine
MTX
Example of anti-IL 12/23
Ustkeiumab
Complications of extra-intestinal features
LIVER - primary sclerosing cholangitis Anaemia thrombosis Urinary stones gallstones Osteoporosis Skin, eyes, joints
How are joints affected?
Saroiliitis
Ankylosing spondylitis
Large joint arthropathy
Small joint arthropathy
How is the liver affected?
Primary sclerosing cholangitis
- increasing risk of cancer in bile duct and colon
- itching and jaundice
Fatty Liver
Autoimmune hepatitis
Colorectal Cancer
Increased risk in IBD >10 years
>8 years screening offered
- increased risk if extensive colitis, chronic inflammation and sclerosing cholangitis
- screening looks for macro and microscopic dysplasia
What causes IBS?
Diet Psychological Dysbiosis Motility Chronic Pain
How do you diagnose IBS?
Faecal calprotectin to prove they don’t have IBD
Who is more likely to have IBS?
Young - teens to 20s
female 2:1
Presentation of IBS
Relief after defecation With or without bloating No nocturnal symptoms Normal FBC/CRP/coeliac screen/haemetinics/TFTs Normal faecal calprotectin
Differentials for IBS
Coeliac Disease- everyone should have coeliac screening
Bile Salt Malabsorption
Parasitic Infection
Small Intestinal Bacterial Overgrowth
Neuroendocrine tumours - fasting gut hormones
Hyperthyroidism
Carcinoid syndrome
IBS Tx
reassurance FODMAP Sparing use of anti-spasmodics CBT if need ABs in some Probiotics Anti-depressants
