GI Flashcards
What does inflammatory bowel disease comprise of? (IBD)
Ulcerative colitis Chron’s disease
Pathophysiology of IBD?
Inflamed intestines Associated with HCAB27 (Seronegative spondyloarthropathy) Has a Bimodal age distribution (15-20, 55+)
Cause of Chron’s disease?
Environmental and genetic - CARD15/NOD2 mutation => strong genetic component - bacteria trigger an immune mediated response (t-cells)
What part of the gut does Chron’s disease affect?
Whole gut Especially terminal ileum and proximal colon (usually rectum is spared)
Risk factors for Chron’s
Family history Jewish HLA-B27 gene Smoking (2x as likely) Caucasian
Pathophysiology of Chron’s
-Characterised by skip lesions (lesions with gaps in between) arising anywhere between the mouth and the anus -End result is transmural inflammation (in all layers) with granuloma formation => resulting in fistulas, strictures and adhesions
Signs and symptoms of Chron’s disease?
Diarrhoea- most significant symptom in adults -Abdominal pain- most significant symptom in kids -Gallstones and kidney stones -Weight loss and lethargy -B12/folate/ Fe deficiency due to malabsorption in small intestine -Apthous mouth ulcers
Extraintestinal manifestations of both Chron’s and Ulcerative Colitis
Eyes:Episcleritis = chrons> Uveitis = UC> Cutaneous: Erythema nodosum Pyoderma gangrenosum Musculoskeletal: Arthritis (most common manifestation in both) Spondylarthritis “spine ache” Osteoporosis Clubbing Also 90% of UC patients have PSC but also sometimes present in patients with Chron’s
Investigations to diagnose Chron’s
-Feacal calprotectein = raised (inflammation in GI tract + differentiates IBD from IBS) -FBC -CRP/ESR -U&Es -Colonoscopy = skip lesions, cobblestone mucosa, deep ulcers -Biopsy = transmural inflammation, granulomas and goblet cells
How to differentiate UC from Chron’s particularly in the peadiatric population?
Serum antibody markers: - pANCA more associated with UC - ASCA more associated with Chron’s
How to differentiate IBD from IBS?
Faecal calprotectin Raised in IBD and not IBS
General management tips for Chron’s
Smoking cessation advice = crucial -Some evidence that NSAIDs and/or combined oral contraceptive pill can increase risk of relapse
Treatment given to induce remission in mild and moderate Chron’s
Elemental diet (alone or with meds, particularly in young people) Mild Chron’s: FIRST LINE : glucocorticoids (PO predinsolone or IV hydrocortisone) SECOND LINE: aminosalicylate (eg mesalazine) Moderate Chron’s: Add in: FIRST LINE: azathioprine or mercaptopurine SECOND LINE: Methotrexate
Treatment for severe Chron’s to induce remission that is unresponsive to conventional therapy
Infliximab or adalimumab as monotherapy or combined with other immunosuppressant
Treatment for Chron’s if it is refractory to medical therapy or disease limited to the distal ileum to induce remission
Surgery
How to classify severity of Chron’s
Mild: - first prevention or - 1 exarcerbation in 12 months Moderate: - >= exarcerbations in 12 months or - glucocorticoid cannot be tapered for management of mild disease Severe: - unresponsive to conventional therapy AND - >= symptoms eg weight loss, fever, severe abdominal pains - usually >3 loose stools per day
How to maintain remission in Chron’s
1st line: azathioprine or metcaptopurine 2nd line: Methotrexate Post surgery: consider azathioprine with or without methotrexate
Frequency of surgery in Chrons patients?
Approx 80% of patients with Chron’s will require surgery but this is not curative as entire bowel can be affected. By removing ‘x’, ‘y’ can flare up.
Complications of Chron’s
Peri-anal abscess Anal fissure Anal fistula Strictures and obstruction
Location of ulcerative colitis
COLON ONLY start at rectum—> sigmoid colon—> proximal colon Never proximally beyond illeocaecal valve Doesn’t affect the anus
Aetiology of ulcerative colitis
Not well understood Autoimmune colitis associated with HCA B27 gene Involves polygenic predisposition and env factors
Risk factors for ulcerative colitis
Family history HLA b27 Caucasian Non-smokers Bimodal age distribution 15-25 and 55-70yrs
Physiopathology of ulcerative colitis
Histopathology will show mucosal and submucosal ulceration as well as crypt abscesses with neutrophil infiltration
Symptoms of ulcerative colitis
Abdominal pain in left lower quadrant -Urgency and tenesmus (pain on defecation) -Bloody mucosy watery Diarrhoea