Coeliac Disease

Question 1

Describe the epidemiology of coeliac disease?

Answer 1

Females more susceptible than males.
Any age.
1% of UK - rare in africa.
10% prevalence in first degree relatives.
96% due to HLA-DQ2 (rest are usually HLA-DQ8) .

Question 2

What is the infectious hypothesis of coeliac disease?

Answer 2

If infected with adenovirus 12 and genetically susceptible, a peptide in alpha-gliadin is similar ot that in E1b portion of the virus. This can lead to cross reactivity with alpha-gliadin.

Question 3

Describe the pathophysiology of alpha-gliadin reaction in coeliac disease?

Answer 3

alpha-gliadin digestion produces a stable peptide which is absorbed into the lamina propria.
Exposure to TTG from damaged epithelia leads to deamination of glutamine and bonding to HLA-DQ2.
This activates proinflammatory T cell responses.

Question 4

How would infants, older children and adults present with coeliac disease?

Answer 4

Infants: Usually 4-24 months when cereals have been introduced. Impaired growth, diarrhoea, vomiting, abdominal distention.

Older Children: Anaemia, short stature, pubertal delay, abdominal pain.

Adults: Diarrhoea, bloating, flatulence, abdominal pain, chronic/recurrent IDA, nutritional deficiency, refuced fertility/amenorrhoea, osteoporosis, unexplained high AST/ALT, neurological symptoms e.g. epilepsy.

Question 5

Describe the pathology of coeliac disease?

Answer 5

Muscosal inflammation can vary and be patchy.
Loss of villous height - can be short, broad, flat, atrophied.
Mucosal thickness stays the same as crypts elongate (hypertrophy).
Increased plasma cells and intraepithelial lymphocytes.

Question 6

List some indicators of small bowel disease?

Answer 6

Malabsorption/electrolyte imblalances: Folate, Calcium, Vit. D, Vit K (coagulopathy), Magnesium.
Chronic or recurrent IDA.

Question 7

How is coeliac disease diagnosed?

Answer 7

Serology;

• IgA tTG
• IgA EMA

Endoscopy;

• Scalloping of intenstinal folds, less folds.
• Mozaic ‘crakced mud’ patterned mucosa.
• Prominant submucosal vessels and nodular mucosa.

Biopsy;

• From distal duodenum.
• Minimum 4 biopsies due to patchy changes.
• Must be on gluten-rich diet.

Question 8

List some diseases associated with coeliac disease?

Answer 8

Giardiasis (parasitic infection).
Dermatitis herpetiformis (itchy rash on extensor surfaces).
Type 1 diabetes.

Question 9

Outline dietary advice for coeliac disease?

Answer 9

Avoid wheat, barley and rye.
Can still eat oats, rice, maize.

Need to watch out for lactose intolerance due to destruction of brush border enzymes due to villous atrophy.

Question 10

Outline other complications of having coeliac disease?

Answer 10

Infection: Functional hypospelnism (lymphocyte loss).
Osteoporosis
Refractory Coeliac Disease: Recurrent malabsorption despite strict adherence to a gluten free diet.
Cancer: Small bowel adenocarcinoma (risk decreased if you adhere to gluten free).