ULCERATIVE COLITIS
DEFINITION
A chronic idiopathic bowel disease which is characterized by
inflammatory changes to the mucosa of the colon, with a clinically
variable course of remissions and relapses, as well as
extra-intestinal manifestations.
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INCIDENCE
Smoking appears to decrease risk in favour of Crohn's
See Crohn's for general IBD risk factors
- Most common in teens - twenties
- Second peak at 40-60y
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AETIOLOGY
Idiopathic
Implicated factors:
- genetics: weak; family
hx only in 10%; also 10% identical twin concordance cf 3% fraternal
- post-infectious agents?
- immunological; e.g. IL imbalance; IL-2 deficiency?
Diet and psychological factors probably not important in relapses
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BIOLOGICAL BEHAVIOUR
Pathology
Inflammatory changes start in
rectum and moves continuously proximally;
- no SB disease except occasional backwash ileitis
The lesion is characterised by mucosal / submucosal inflammation (serosal surface is
normal)
In the active phase, the mucosa is reddened with a granular surface,
with loss of haustra in chronic disease
- islands of regenerating mucosa protrude outwards as pseudopolyps.
Microscopically: there are crypt
abscesses, diffuse mononuclear infiltrate, loss of goblet
cells
- and epithelial dysplasia
(also metaplasia, eg Paneth cells) may progress to cancer.
Natural History
At first presentation, 25% of patients have total colitis (poor
sign), 50% have left-sided colitis and 25% have proctitis only.
Sometimes the first attack is the last but 97% will have a relapse
in next 10 years
- 60% have mild disease
- 30% require total colectomy;
Typically involves disease flares followed by periods of relative
remission.
Extra-intestinal manifestations are more marked than in Crohn's, and may be immune-complex
mediated.
Malignancy
Increased risk of colorectal malignancy
Associated with duration and risk
- low in first 8-10y
- increases 1-2% annually therafter.
- 30 years of UC = 10% risk
Occurs in a different pathway, not in polyps
Surveillance annually after 8-10y
- if dysplasia, proctocolectomy (low grade = 20% risk or a cancer;
high-grade = 50% risk).
Extra-intestinal
Associated with migratory polyarthritis, sacroiliitis, ank spond,
uveitis, hepatic involvement and skin lesions.
Also primary sclerosing cholangitis
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MANIFESTATIONS
Symptoms
Local
Spectrum from mild to severe.
Diarrhoea (often with blood and stringy mucus), frequent bowel
motions, tenesmus, LLQ discomfort
- first presentation can be to ED due to bleeding / fluid and
electrolyte loss.
- often exacerbated by stress.
Systemic
Fever, malaise, weight loss
Extra-intestinal
Large joint polyarthropathy (20%) in knees, ankles, elbows, wrists
Erythema nodosum, pyoderma gangrenosum, aphthous ulceration in mouth
Sclerosing cholangitis, cholangiocarcinoma
Signs
Those of extra-intestinal manifestations
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INVESTIGATIONS
Diagnosis is made from combo of clinical, endoscopic,
radiological, histopath and serological criteria.
MCS
Rule out C diff, CMV, cryptosporidium, giardia.
Radiology
AXR may show non-specific dilation; thickening
CT often performed to evaluate SB (or enterography / capsule
endoscopy)
Endoscopy
Colonoscopy including ileal intubation and biopsies is essential.
Serology
p-ANCA (perinuclear antineutrophil cytoplasmic antibodies) are
associated but not highly sensitive.
Indeterminant colitis
10% of patients do not get a definitive diagnosis.
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MANAGEMENT
Principles
1. Emergent colectomy should
be avoided
- higher morbidity, imperfect long term outcomes.
Majority of patients will respond to modern medical therapy.
- agents like infliximab
have reduced incidence of toxic colitis.
25-30% eventually require surgery, typically for:
- intractable disease
- malignancy
- fulminate colitis
- intolerance to medical management.
Non-operative
Mild attacks
Rectal steroids in a foam or liquid enema, or oral sulphasalazine
(5-ASA with a sulphur and salicylic acid component)
Moderate attacks
Oral steroids or IV hydrocortisone
Severe attacks
(>6 bowel motions/day, temp >37.5, albumin <30g/l)
Risk of toxic megacolon, perforation
Oral or IV cyclosporin. Remission maintained on sulphasalazine,
azothiaprine
Operative
Indications
for Surgery
Emergency
Toxic megacolon
Uncontrolled haemorrhage
Perforation
Urgent
Fulminant colitis
Anaemia
Elective
Intractable disease
Dysplasia / cancer
Side effects of medications
Relative indications
Associated diseases
- derm and ocular manifestations often improve with colectomy
- others, eg PSCholangitis and ank spond appear to act independently
and do not.
Fulminant colitis
8 bloody BMs / day
SIRS - tachycardia, fever
Anaemia
AND failing to respond to IV steroids within 48-72h +/- trial of
infliximab.
Can progress to toxic megacolon
- often severe SIRS / systemic upset, hypoalbuminaemia with dilated
colon.
Acute Surgery
Open total abdominal colectomy with end ileostomy.
Avoid lap approach - friable colon and high risk of perf.
Rectal stump:
- stabled transection at rectosigmoid jx, or preserve and
exteriorize mucus fistula; open or closed
- mucus fistula perhaps preferable as is safe, reduced abscesses,
facilitates future pelvic dissection.
- either way preserve superior rectal vessels
- and place a rectal tube
Often several months or more before ready for proctectomy with or
without restorative procedure.
Elective Surgery
Principles are to remove disease tissue, preserve intestinal
continuity if possible
Options:
- decision depends on disease, functional status, age and
patient preference
1. Total Proctocolectomy and End ileostomy
Curative, but permanent stoma.
Perineal proctectomy facilitates layered perineal closure, lowers
risk of perineal wound problems.
2. Total Abdominal colectomy and
ileorectal anastomosis
Suitable if minimal rectal disease, able to have frequent
surveillance
- increased risk of cancer in the rectal stump (10% at 20y)
- 10% risk of proctitis requiring proctectomy
- 10% risk of fecal incontinence
Abdominal colon removed, ileorectal anastomosis at level of sacral
promontory.
End to side may be preferable to mitigate against bowel size
difference at join
Low risk of leak or sexual / bladder problems.
Fibre and anti-diarrhea agents mitigate multiple daily bowel
operations.
3. Continent Ileostomy
Ileum used to create a nipple valve and pouch reservoir.
Valve formed by intussusception of efferent limb.
Patients relieve by inserting a catheter.
Uncommonly used as high revision rates and increasing use of
something better:
4. Restorative Proctocolectomy
Operation of choice in elective UC.
Also called ileal pouch anastomosis (IPAA)
Not suitable if acute disease, high risk ,low rectal cancer or
Crohn's
Usually a two stage: IPAA with covering ileostomy then reversal.
Acute patients can have a three stage - total colectomy with end
ileostomy, proctectomy with IPAA and diverting loop, then reversal.
See procedure for more details.
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