LGI Autoimmune - Ulcerative Colitis, Crohns disease, Coeliac disease

Question 1

Ulcerative colitis vs Crohns
-epidemiology
-risk factors

Answer 1

20-30s, both sexes

FHx, genetic
Smoking
-harmful in CD => significant trigger for flares
-protective in UC

UC
-rectum, continuous spread to ileocecal valve
-submucosal inflammation

CD
-mouth to anus, skip lesions
-full thickness inflammation

Question 2

UC vs CD
-presentation

Answer 2

Relapsing remitting
-weight loss, tired from malabsorption, inflammation

UC
-bloody diarrhoea
-urgency, tenesmus
-abdo pain normally in LLQ

CD
-frequent, urgent non-bloody diarrhoea
-abdo pain depending on affected bowel segment

Question 3

Crohns pathophysiology

Answer 3

Full thickness inflammation - TERMINAL ILEUM + COLON

• inflammation => abdo pain
• chronic => thickens wall, fistula, strictures, adhesions
• skip lesions => diarrhoea, no tenesmus

Terminal ileum - most commonly affected

• reduced B12, fat uptake => macrocytic megaloblastic anemia, steatorrhea
• increased unabsorbed fat binds to Ca instead of oxalate => oxalate renal stone

Reduced ability to absorb nutrients => weight loss, malnutrition

Question 4

UC pathophysiology

Answer 4

Rectum => extends proximally to terminal ileum

• continuous mucosal inflammation => crypt abscess, goblet loss, bloody tenesmus diarrhoea, crampy pain
• thinning colonic wall => toxic megacolon, perforation

Question 5

Extra-intestinal manifestations of IBD

Answer 5

A ESCAPE
Apthous ulcers
Erythema nodosum
Sclerosing cholangitis (UC)
Clubbing
Arthritis
Pyoderma gangrenosum
Extraocular (uveitis UC, episcleritis C)

Question 5

Diagnosis and investigations of IBD

Answer 5

Fecal calprotectin - GI inflammatory marker but not specific
-CRP
-VitB12, folate, anemia, LFT - nutritional status

Enemas
- Crohns - strictures, fistulas, proximal bowel dilation, rose thorn ulcer
- UC - no haustrations, drainpipe

Definitive - endo/colonoscopy with biopsy to confirm
- Crohns - cobblestoning, skip lesions, non caseating granulomas
- UC - pseudopolyps, crypt abscess,
Use sigmoid during severe flares to reduce risk of perforation

Question 6

Medical management of CD and UC
- acute
- remission

Answer 6

CD
Lifestyle - stop smoking

Induce remission
1st line - GC
2nd line - 5ASA (mesalazine), can add aza/mercatopurine
3rd line - infliximab (TNFa) + aza/metho

Maintenance
1st line - Azathiopurine or mercatopurine
-TEST TPMT ACTIVITY
2nd line - metho

UC
Induce remission
1st line - 5ASA
-rectal if limited to LHS
-rectal + PO if not limited to LHS
2nd line or if systemic upset + 6 bloody stools/day - IV CS
3rd line if unresponsive to IV CS => IV ciclosporin or AZA

Maintenance
Mild - 5ASA
Severe - thiopurine if 2+ exacerbations in 1 year/severe flare

Question 7

Surgical management for CD
-why

Answer 7

Strictures - stricturoplasty

Perianal fistula (channel between anal canal and perianal skin formed from inflammation
Ix - MRI
-metronidazole/infliximab
-seton to keep fistula open, reduce risk of abscess forming

Perianal abscess
-incision and drainage + ABx

Question 8

Surgical management for UC
-why

Answer 8

Toxic megacolon, perforation, severe bleeding, failing to respond medically - removal of part of/whole colon

Formation of
-ileostomy
-anastomosis
-J pouch
Can be permanent or temporary

Symptoms cannot return if there is no colon and rectum
-but extraGI manifestations may remain
-no risk of bowel cancer
-can reduce medication use

Question 9

Coeliac disease
- causes
- pathophysiology and presentation
- associated conditions

Answer 9

AI response to gluten
HLA DQ2-8

Chronic inflammation in presence of gluten - crampy pain,

Jejenum most commonly affected - folate uptake affected more than Fe (duodenunm) or B12 (ileum) => anemia, peripheral neuorpathy, hyposplenism
Malabsorption => diarrhea, weight loss, steatorrhea, osteomalacia (VitD deficiency)

High associations with
- T1DM, AI thyroiditis
- dermatitis herpetiformis - itchy, vesicles on extensors from IgA deposition

Question 10

Coeliac disease
-investigations and diagnosis
-management

Answer 10

Ensure they have been eating gluten for 6wks
Serology - TTG IgA/G, endomyseal IgA
DEFINITIVE - biopsy
-villous atrophy, crypt hyperplasia, high lymphocytic infiltration
HLA DQ2-8 testing

Gluten free diet - no wheat, rye, barley

Supportive
- nutritional support
- manage associated conditions

Question 11

Classification of ulcerative colitis flares
-mild

Answer 11

U4 stools daily (with/without blood)

No systemic disturbance

ESR, CRP normal

Question 12

Classification of ulcerative colitis flare
-moderate

Answer 12

4-6 stools daily

Minimal systemic disturbance

Question 13

Classification of ulcerative colitis flare
-severe

Answer 13

6+ stools daily (with blood)

Systemic disturbance
-fever
-tachycardia
-abdo tenderness, distention, reduced bowel sounds
-anemia
-hypoalbuminuria

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