Coeliac Disease Flashcards
Define coeliac disease
Inflammatory disease of SMALL COLON caused by intolerance to gluten, causing chronic intestinal malabsorption
Aetiology
Genetics - HLA-B8, DR3, DQW2
Sensitivity to gliadin component of gluten
Triggers immunological reaction in the small intestine, leading to mucosal damage and loss of villi
Epidemiology
1/2000 in UK
1/300 in west of Ireland
Rare in east asia
History/symptoms
Asymtomatic Abdo discomfort, pain, bloating Steatorrhoea/diarrhoea Tiredness, malaise, weight loss despite normal diet Failure to 'thrive' in children Amenorrhoea in young adults
Which three genetic markers are associated with coeliac disease?
HLA-B8
DR3
DQW2
Explain the pathophysiology behind malabsorption
Sensitivity to gliadin component of gluten
triggers an immunological reaction in the small intestine, leading to mucosal damage and loss of villi
Signs
Anaemia - pallor
Malnutrition - short stature, abdo distention, wasted buttocks in children
Vitamin/mineral deficiencies e.g. osteomalacia, easy bruising
Dermatitis herpetiformis - Intense itchy papulovesiclualr blisters on extensors e.g. elbows, knees or buttocks
?clubbing
What would you look at as an indication of fat stores?
Triceps skinflap
Explain the pathophysiology behind dermatitis herpetiformis
Normally, gliadin is de-amidated by tissue transglutaminase (tTG), however there is often a cross reaction where the antibodies produced against tTG also bind to epidermal transglutaminase and thus cause these herpes-like blisters!
Initial investigations
FBC Serology Stool culture D-xylose test Endoscopy
What would you look at in an FBC for coeliac disease?
- low iron
- low folate
- low Hb
U&Es
Albumin (protein losing enteropathy)
Calcium
Phosphate
What serological tests would you conduct?
Tissue transglutaminase (TTG) IgG anti-gliadin (AGA) IgA and IgG anti-endomysial transglutaminase
What else must you do with serology?
Measure immunoglobulin levels as low IgA is common in coeliac disease
What percentage of people have an IgA deficiency?
1/50
Why do you do a stool test?
To exclude infection
To look at fat content (faecal fat tests for steatorrhoea)
Explain a D-xylose test
You give a pt oral xylose
If there is reduced urinary excretion, it suggests malabsorption
What would endoscopy show?
Flat, smooth mucosa and villous atrophy in small intestine
What would a biopsy show of the:
- villi
- crypt
- epithelium
- lamina
- propria
Villous atrophy
Crypt hyperplasia of duodenum
Cuboidal appearance of epithelium (should be simple columnar)
Inflammatory infiltrate in lamina propria
Management
Gluten avoidance
Avoid all types of wheat, rye and barley products
Vitamin and mineral supplements
Oral corticosteroids if disease does not subside with gluten withdrawal
Complications
Iron, folate and B12 deficiency
Osteopenia/osteoporosis
Ulcerative jejunoileitis
Bacterial overgrowth
Rarely cerebellar ataxia
Small bowel lymphoma = EATL (enteropathy-associated T-cell lymphoma)
Prognosis
With strict adherence to gluten-free diet, most patients make a full recovery.
Symptoms usually resolve within weeks. Histological changes may take longer to resolve. A
gluten-free diet needs to be followed for life.
What might be seen on biopsy?
Villous atrophy
WBC infiltration
Cryptal hyperplasia
Further investigations
Refer to: Dietitians Biopsy Screening for first degree relatives Bone density scan
What would you do if someone’s symptoms don’t improve with a gluten free diet?
Rerefer to dietitian to ensure diet is strictly adhered to
Repeat TTG/serology
