Coeliac Disease Flashcards
In what foodstuffs is gluten present?
Wheat
Barley
Rye
What is gluten broken down into which T cells react to in coeliac disease?
Alpha gliadin
Females and more susceptible than males to develop coeliac disease. T/F?
True
How many people with coeliac disease carry the HLA-DR2?
95%
Other than HLA-DR2 what is the other gene which makes a person susceptible to coeliac disease?
HLA-DR8
All people with the HLA-DR2 gene will develop coeliac disease. T/F?
False
There is a theory that infection in genetically susceptible individuals can cause coeliac disease. Infection with which virus is thought to do this?
Adenovirus 12
How does coeliac disease present in infants?
Presents around 4-24months Impaired growth Diarrhoea Vomiting Abdominal distension
How does coeliac disease present in older children?
Anaemia Short stature Pubertal delay Recurrent abdominal pain Behavioural disturbance
How does coeliac disease present in adults?
IBS like symptoms Dirahhoea Flatulence Abdominal discomfort Iron deficient anaemia Reduced fertility or amenorrhoea Oestoporosis Unexplained increase in ALT/AST
Describe the physiology of coeliac disease?
Alpha gliadin is digested and absorbed intact into the lamina propria through tight junctions which are often leaky in coeliac disease. Exposure to tissue transglutaminase (ttg) will deaminate alpha gliadin and this deaminated gliadin will be processeed by macrophages which oresenf the protein to CD4+ T cells via MHC II molecules coded for by HLA-DR2/8. This causes an inflammatory reaction mediated by t cells whoch damages enterocytes and activated B cells to produce anti ttg and anti EMA antibodies
What effect does coeliac disease have on a histological level?
Villi becomes short and flattened
Hypertrophy and elongation of crypts
Increase in plasma and intraepithelial lymphocytes
Coeliac disease can cause steatorrhea, fat malabsorption, vitamin deficiency, abdominal pain and vomiting. T/F?
True
Vitamin malabsorption (of K and D) can result from coeliac disease. What cknsequences can this have?
Vit d - oestoporosis
Vit k -coagulopathy
Why does vitamin b12 malabsorption rarely occur with coeliac disease?
Because coeliac disease mainly effects the duodenum and vit b12 is mostly absorbed in The terminal ileum
How is coeliac disease diagnosed?
Serology tests for IgA tTG antibkdy and IgA EMA antibody (although in IgA deficient people this will be an IgG antibody)
Endoscope with biopsy when patient is on gluten rich diet
Why are several biopsies taken when investigating potential coeliac disease?
Because coeliac disease causes a patchy pathology
Which classification system can be used when looking at coeliac disease biopsy?
Marsh classification
What diseases are associated with coeliac disease?
Dermatitis herpetiformis
Type I diabetes mellitus
Thyrotoxicosis
Addisons disease
What are the differential diagnoses of coeliac disease?
Giardiasis CVIDQ Chrons Lymphoma Whipples disease Tropical sprue Chronic ischaemia NSAID use
How is coeliac disease treated?
Gluten free diet should see symptomatic improvement in two weeks
Vaccination for certain infections that coeliacs are more susceptible to
Vitamin d supplementation to avoid osteoporosis
What is refractory coeliac disease?
Recurrent malabsorptive symptoms and villous atrophy despite strict adherence to GF diet for at least 6-12 months in the absence kf other causes of non responsive treated coelkac disease and overt malignancy
How can type I refractory coeliac disease be mananged?
Immunosuppressants such as steroids kr azathioprine
Why does type II refractory coeliac disease have a low survival level?
Because it usually progresses to enteropathy associated t cell lymphoma
What are the symptoms of enteropathy associated t cell lymphoma?
Weight loss Night sweats Itch Overt or occult GI bleeding Venous thromboembolism
What percentage of enteropathy associated t cell lymphomas are caused by coeliac disease?
13%