Coeliac disease Flashcards
Coeliac disease is an immune response where the body initiates an immune response to gluten causing inflammation of the intestines. What % of the population are estimated to have coeliac disease?
1 - 1%
2 - 10%
3 - 25%
4 - 50%
1 - 1%
- immune-mediated small intestinal (SI) enteropathy (intestinal disease)
- triggered by exposure to dietary gluten in genetically predisposed individuals, leading to malabsorption
Coeliac disease is caused by a protein called gluten, which of the following common products is gluten least likely to be found in?
1 - wheat
2 - barley
3 - rye
4 - oats
4 - oats
- can be contaminated due to interactions with other gluten containing foods
Coeliac disease is caused by a protein called gluten, what specific part of gluten is associated with coeliac disease?
1 - gliadin
2 - glutenin
3 - heme
4 - avenalin
1 - gliadin
- umbrella term for a group of gluten peptides
- all share 33 amino acid sequence triggering immune response
Are men or women more susceptible to coeliac disease?
- women are more susceptible
- this may be because women are more likely to seek help then men
Where in the world is coeliac disease most common?
1 - south America
2 - USA and Europe
3 - Canada
4 - Australasia
2 - USA and Europe
- very common in Ireland and Scandanavia
- can typically occur in childhood, but can occur at any age
Coeliac diseases induces and immune response. Patients diagnosed with coeliac disease are likely to have all or some of the the following conditions, EXCEPT which one?
1 - down’s syndrome
2 - Type 2 diabetes mellitus
3 - auto-immune hepatitis
4 - thyroid gland abnormalities.
2 - Type 2 diabetes mellitus
- not an immune response
- type 1 diabetes is common
Are children of parents who have coeliac disease more likely to develop coeliac than the general population?
- yes
- 1st degree relatives of patients
- greater concordance in monozygotic (identical) twins (75%)
Which 2 of the following genes that have been shown to correlate with coeliac disease?
1 - Human Leukocyte Antigen (HLA) DQ2 genes
2 - Human leukocyte antigen (HLA) DRB1 genes
3 - Human Leukocyte Antigen (HLA) DQ8 genes
4 - Human Leukocyte Antigen (HLA) B27 genes
1 - Human Leukocyte Antigen (HLA) DQ2 genes
3 - Human Leukocyte Antigen (HLA) DQ8 genes
- HLA genes encode MHC-II molecules and tell them what to bind with, such as gliadin
- HLA DRB1 = RA
- HLA B27 = spondylitis
Patients with coeliac disease typically present with all of the following symptoms, EXCEPT which one?
1 - diarrhoea
2 - steatorrhea (fatty floating stools)
3 - bloody stools
4 - weight loss.
5 - anaemia (iron, B12 and folate malabsorption)
6 - fatigue
7 - vague abdominal pains/bloating
3 - bloody stools
- but 1/3 of patients can also be asymptomatic
What clinical signs can we often identify in patients with coeliac disease?
1 - mouth ulcers/glossitis
2 - dermatitis herpetiformis (itchy/blistering)
3 - raised autoantibodies
4 - all of the above
4 - all of the above
- dermatitis herpetiformis (itchy/blistering) rash caused by IgA antibodies mistakenly bind to tissue transglutaminase in epidermis of the skin
- common around umbilicus and knees
The most common symptoms that patients with coeliac disease present with include diarrhoea, steatorrhea (fatty floating stools), weight loss, anaemia, vague abdominal pains. Which part of the GIT is most commonly affected in coeliac disease?
1 - stomach
2 - jejunum
3 - ileum
4 - duodenum
2 - jejunum
- commonly affects duodenum as well
What is the name of the rash in the image below that patients with coeliac disease present with?
1 - dermatitis herpetiformis
2 - excema
3 - dermatomyositis
4 - psoriasis
1 - dermatitis Herpetiformis
- an itchy, vesicular rash on extensor surfaces
In the image below are 3 signs of coeliac disease. From left to right match the labels with the symptoms?
- angular stomatitis (iron/vit B12 deficiency)
- glosittis (iron deficiency)
- pallor (anaemia)
- far left = pallor (anaemia)
- middle = angular stomatitis (iron/vit B12 deficiency)
- far right = glosittis (iron deficiency)
Gliadin is able to be absorbed by the small intestines and enter the lamina propria, what are the 2 ways gliadin is able to cross epithelial cells in the small intestines?
- paracellular (between cells and tigh junctions)
- transcellular (through cells)
Gliadin is able to be absorbed by the small intestines, either paracellular (between cells and tight junctions)or transcellular (through cells) where it comes into contact with the lamina propria. Once into the lamina propria what is the 1st thing that happens to the gliadin?
1 - macrophage engulfs gliadin and presents it on its MHC-II complex
2 - enzyme tissue transglutaminase (tTG) removes amide group forming deaminated gliadin
3 - B cells produce antibodies against gliadin and tTG
4 - CD4 T-helper cell bind to MHC-II complex and releases cytokines (interferon gamma and TNF-a)
2 - enzyme tissue transglutaminase (tTG) removes amide group forming deaminated gliadin
Gliadin is able to be absorbed by the small intestines and enter the lamina propria. Once into the lamina propria the enzyme tissue transglutaminase (tTG) removes amide group producing deaminated gluten protein. What happens to the deaminated gluten proteins?
1 - macrophage engulfs gliadin and presents it on its MHC-II complex
2 - CD8 T cells bind and induce apoptosis in inflamed epithelial cells
3 - B cells produce antibodies against gliadin and tTG
4 - CD4 T-helper cell bind to MHC-II complex and releases cytokines (interferon gamma and TNF-a)
1 - macrophage engulfs gliadin and presents it on its MHC-II complex