Ulcerative Colitis Flashcards
Define ulcerative colitis?
Chronic relapsing and remitting inflammatory disease affecting the large bowel
Starts in rectum and spreads proximally, always continuous (DOES NOT AFFECT THE ANAL CANAL OR ANAL TRANSITIONAL ZONE!)
outline the aetiology of ulcerative colitis?
UNKNOWN
Possible genetic susceptibility (chr 12, 16)
Other factors involved: immune response to bacterial or self-antigens, environmental factors, altered neutrophil function and abnormality in epithelial cell integrity
Considered to be Th2 mediated – IL-13 is key
Positive family history - 15% of patients
Associations:
- Elevated serum pANCA
- Primary sclerosing cholangitis (70% of patients with PSC have UC)
- PSC is inflam and scarring of bile ducts
what are the risk factors for UC?
Family history of IBD
HLA-B27
infection
summarise the epidemiology of UC?
Higher prevalence in:
- Ashkenazi jews
- Caucasians
NON-SMOKERS
Uncommon before the age of 10 yrs
Peak onset: 20-40 yrs
Equal sex ratio up to the age of 40 yrs (higher in males from then on)
what are the presenting symptoms of UC?
Bloody or mucous diarrhoea (stool frequency depends on severity of disease)
BLOODY (more likely with UC because ulcers bleed!)
Mucus
Tenesmus and urgency
Crampy abdominal pain before passing stool
Weight loss – remember rarely causes weight loss outside of a flare up
Fever
Diarrhoea - constipation cycles (imp to establish what is normal in them)
Extra-GI manifestations (e.g. uveitis, scleritis, erythema nodosum, pyoderma gangrenosum)
what are the signs of UC on physical examination?
Signs of iron deficiency anaemia (e.g. conjunctival pallor)
Dehydration
Clubbing
Abdominal tenderness
Tachycardia
Blood, mucus and tenderness on PR examination
Extra-GI manifestations (listed above)
what are the investigations for UC?
Stool studies
bloods
AXR
Flexible sigmoidoscopy or colonscopy
barium enema
describe bloods in UC?
FBC:
- Low Hb
- High WCC
High ESR or CRP
Low albumin
pANCA - REMEMBER THIS ANTIBODY
What may be seen on the AXR?
Dilated bowel ( more than 6cm= toxic mrgacolon), thumbprinting
describe the barium enema?
loss of haustrations
superficial ulceration, ‘pseudopolyps’
long standing disease: colon is narrow and short -‘drainpipe colon’
Describe the histology of UC?
No inflammation beyond submucosa(unless fulminant disease) - inflammatory cell infiltrate in lamina propria
neutrophils migrate through the walls of glands to form crypt abscesses
depletion of goblet cells and mucin from gland epithelium
granulomas are infrequent
Describe the colonoscopy/ sigmoidoscopy?
Widespread ulceration with preservation of adjacent mucosa which has the appearance of polyps (‘pseudopolyps’)
loss of haustra
Note don’t perform a colonoscopy in acute severe disease as risk of perforation - do a sigmoidoscopy instead
what is used to maintain remission?
- IMMUNOSUPRESSIVES
- Azathioprine, Mercaptopurine - BIOLOGICS (anti- TNFa)
- Infliximab, Adalimumab - BIOLOGICS (integrin receptor antagonists)
- Vedolizumab - CICLOSPORIN
- TOTAL COLECTOMY
- Cure !!!
what is used to induce remission?
- MESALAZINE (5-ASA)
- Oral / topical - STEROIDS
- Oral Beclamethasone
outline the management of acute exacerbation of UC?
IV rehydration
IV corticosteroids (+ give AdCal for bone protection)
2ndline: Ciclosporin - If refractory to steroids- If contraindicated to ciclosporin, use Infliximab - If refractory to steroids
(3rdline = colectomy)
Bowel rest
Parenteral feeding may be necessary
DVT prophylaxis
If toxic megacolon - the patient is likely to need a proctocolectomy because toxic megacolon has a high mortality
what are the procedures for the surgical management of UC?
Proctocolectomy with ileostomy– surgical removal of colon, rectum and anal canal
Ileo-anal pouch formation
Compare the extra-intestinal features of crohns and UC?
what criteria is used to determine the severity of UC?
True love and Witts criteria
