IBD (crohns and UC) Flashcards
What are the key features of inflammatory bowel disease?
Two chronic idiopathic disorders: Crohns disease and UC - relapsing and remitting inflammation of the GIT.
Define chrons disease?
Type of IBD - characterised by transmural inflammation affecting any part of the GIT from mouth to anus.
What is the key epidemiology of Crohns disease?
20-30yrs peak - equal between men and women
Near equal rates to UC
Less common than coeliac disease and colorectal cancer
What is the underlying aetiology of chrons disease/UC?
Genetics - first degree relative - NOD2/CARD15/HLA gene (bacterial recongition and inflammatory responses)
Environ - smokers (protective in UC), diet (high in fat/sugar/processed foods and low in fibre)
Chronis NSAID use
Appendectomy - uncertain why
Dysbiosis of microbiota (reduce firmicutes inc actinobacteria and protoebacteria) - may relate to antibiotic use
Ingections - mycobacterium avium, E.coli and listeria monocytogenes.
What is the basic pathophysiological process underpinning Crohn’s disease?
Loss of intestinal epithelial barrier integrity increases permeability to bacteria
APCs trigger immune response which is propagated by pro-inflam cytokines, neutrophil/macro phage recruitment
Granulomas and transmural inflammation - hallmark of response
Persistent inflammation can lead to stricures, fistulas and abscesses.
What are the diamond points of Crohns pathophysiology?
Transmural inflammation
Skip lesions
Granulomas
Most commonly the terminal ileum
What are the typical GIT clinical features of Crohns disease?
Abdominal pain - (RLQ)
Diarrhoea - non-bloody most the time
Weight loss - secondary to anorexia, malabsorption and nutritional deficiencies (can be anaemic)
Perianal disease - fissures and abscesses, fistulas.
Oral - aphthous ulcers
Obstructive symptoms - from strictures, adhesions -> N&V, distention and constipation
What are the extra-intestinal manifestations of Crohns disease/UC?
Arthritis -> large peripheral joints (knees, wrists)
Skin - erythema nodosum (pain, raised, red on lower extremities)
Ocular - eye pain, photophobia and blurred vision
Hepatobiliary manifestation - Primary sclerosing cholangitis
Haematological - anaemia, inc risk of Thromboembolic events.
What are the key investigations for Crohns disease/UC?
Bedside: FIT test, stool tests (faecal calprotectin)
Bloods: FBC, CRP, ESR, LFT, iron studies, VitB12, folate, serological markers (ASCA, pANCA)
Imaging: colonoscopy
How can ASCA and pANCA differentiate between ulcerative colitis and crohns disease?
ASCA - cronhs disease
pANCA - ulcerative colitis
What is a key way to differentiate between IBD and IBS?
IBD - faecal calprotectin is elevated, pain is persistent and may have nocturnal symptoms
IBS - is not, pain relieved by defecation, uncommon to have nocturnal symptoms
What are the key histopathological features of crohns disease?
Transmural inflammation
Lymphoid aggregates
Crypt architectural abnormalities
Cryptiris
Crypt abscesses
What lifestyle advice might patients with Crohns disease by given?
Stop smoking
Reduce/stop NSAIDs and COCP - inc risk of relapse
How is remission induced in Crohns disease?
If first in 12 months period = Glucocorticoids (prednisolone) first line, may consider budesonide or aminosalicylates(mesalazine) (not if severe disease)
Consider enteral nutrition is concerns over suppressed growth particularly in children
What second line treatments may be given for Crohns disease remission?
Azathioprine or mercaptopurine - add ons to glucorticoids (NOT monotherapy)
Infliximab - if refractory and fistulating disease.
Metronidazole for peri-anal disease.
What drugs are given to maintain remission in Crohns disease?
Azathioprine - inhibits DNA replications
Mercaptopurine - purine antagonist - stops DNA replication
Both are immunosuppresant.
Second line = methotrexate
What is the use of surgery in Crohns disease?
Used in 80% of patients
Includes bowel resection, stricturoplasy, abscess drainage
What co-morbid conditions are common in Crohns disease?
Osteoporosis
Malnutrition
Define ulcerative colitis
Chronic inflammatory bowel disease causes continuous colonic mucosa inflammation and ulceration.
What are the key pathological features of ulcerative colitis?
Mucosal and submucosal inflammation only
Architecture - irregular, shortend crypts, crypt branching and increased crypt density -high neutrophil density.
Paneth cells metaplasia - in the left colon and rectum.
What are the different classifications of ulcerative colitis based on anatomical location?
Ulcerative proctitis - limited to rectum
Proctosigmoiditis - rectum and sigmoid
Left sided colitis - rectum to sigmoid colon
Pancolitis - entire colon
What are the typical clinical features of ulcerative colitis?
Chronic diarrhoea - urgency or incontinence
Bloody stools - haematochezia
Mucus in stools
Abdominal pain - lower quadrant
Tenesmus
Systemic = fever, fatigue, anorexia and weight loss.
What is the key feature on imaging for Ulcerative Colitis?
Lead piping - loss of haustral markings
Whole colon - no gaps
Compare UC and Crohns disease
Compare the endoscopy for Crohns disease and UC
Crohns - deep ulcers, skip lesions and cobble-stone appearance
UC - widespread ulceration, preservation of adjacent mucosa, appearance of polyps, pseudopolyps
What are the key radiological signs of crohns disease?
Kantors string sign = strictures
Rose thorn ulcers
Proximal bowel dilation
Fistulae
What is the typical management for UC?
First line in mild to mod = aminosalicylates - sulfazalzine, mesalamine
Corticosteroids - moderate to severe or acute flares
Immunomodulators - azathioprine, methotrexate - if fail to response
What biologics may be used for Ulcerate colitis?
antiTNF = infliximab, adalimumab, golimumab
Anti-integrin - vedolizumab
anti-interleukin - ustekinumab
JAK inhibitors = Tofacitinib
How is the severity of ulcerative colitis graded?
Mild = less than 4 stools a day, small blood
Mod = 4-6 stools, varying blood,
Severe = more than 6 stools a day + systemic upset (pyrexia, tachy, anaemia, raised inflammatory markers)
