Page 174 - Medicine and Surgery

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170 Chapter 4: Gastrointestinal system

Macroscopy/microscopy 2 Severe attacks or fulminant colitis should be treated
1 During acute exacerbation there is superficial mucosal with high dose steroids (oral or intravenous).
haemorrhagiculceration,interspersedwithmorenor- Fluid and antibiotic management is often required.
mal mucosa appearing as an inflammatory polyp Ciclosporin may induce remissions in refractory
(pseudopolyps). On microscopy there is oedema and attacks.
lymphocytic infiltration of the lamina propria. Neu- 3 Maintenancetherapyiswithlowdose5-aminosalicylic
trophils migrate through the wall of mucosal glands acid. Steroids can maintain remission but due to
to form crypt abscesses. long term side effects steroid sparing agents such as
2 During remission there is little ulceration, the mu- azathioprine are often used. Azathioprine requires
cosa appears hyperaemic and thin. Microscopy reveals careful monitoring as it may cause abnormal liver
chronic inflammatory cell infiltration. function tests or bone marrow suppression. Azathio-
3 Confluent inflammation and ulceration extending prine should be avoided in patients who are TPMT
into the muscle layer is seen in fulminant disease. (thiopurine-S-methyltransferase) deficient as they are
at particular risk of bone marrow suppression.
Complications 4 Alternative treatments: Intravenous heparin and nico-
Severe fulminant disease may manifest as toxic colonic tine patches have been shown in some studies to help
dilation, septicaemia, obstruction and perforation. induction of remission in refractory UC, but are not
Chronicbowelinflammationisassociatedwithincreased recommended as maintenance therapy.
risk of cellular dysplasia and a significant risk of carci- Surgical treatment: Pan-proctocolectomy with per-
noma. manent ileostomy involves removal of all the
colonic mucosa and is curative.
Investigations Colectomy and ileorectal anastomosis does not
Anaemia due to blood loss, iron deficiency or chronic
require ileostomy but proctitis may persist caus-
disease, acute inflammation may also cause a rise in ing diarrhoea and cancer surveillance is still
platelet count. Inflammatory markers such as ESR are necessary.
often raised in acute exacerbations. Pancolectomy with retention of the anal sphincters
Barium enema may cause perforation in acute dis- allows anastomosis via an ileal pouch. This removes

ease and is therefore contraindicated. In mild disease all diseased mucosa.
a diffusely reticulated pattern is seen with punctate Emergency surgery for perforation, toxic dilation,
collections of barium in small ulcers. In chronic dis- massive bleeding and refractory severe exacerba-
ease a featureless colon with complete loss of folds is tionsmaybenecessarybutcarriesasignificantmor-
seen. Repeated plain abdominal X-ray is of value in tality.
acute flares to diagnose acute colonic dilation.
Colonosocopy with biopsy is diagnostic but may in-

duce megacolon or perforation in severe, extensive Prognosis
disease. Flexible sigmoidoscopy is safer and usually Relapses and remissions with overall prognosis related
adequate. to the extent of the disease. 3–5% of patients with UC
Stool culture and microscopy is used to exclude addi- develop colonic carcinoma, the risk is much greater in

tional infection. those with active disease for more than 10 years.
Management
1 Mild attacks of proctitis or proctosigmoiditis can be Crohn’s disease
treated topically with 5-aminosalicylic acid (5-ASA)
suppositories or enemas or steroid enemas. If these Definition
are not tolerated, or if there is involvement of more of Achronic granulomatous inflammatory bowel disease
the colon, oral 5-ASA or steroids may also be used. (IBD), which may affect the whole bowel (see Table 4.4).