Coeliac disease Flashcards
What are the 5 broad areas that can cause malabsorption?
- Defective intraluminal digestion
- Insufficient absorption area
- Lack of digestive enzymes
- Defective epithelia transport
- Lymphatic obstruction
Why might a patients have defective intraluminal digestion?
- Pancreatic insufficiency
- Defective bile secretion
- Bacterial overgrowth
What could cause insufficient absorptive area?
- Coeliac disease
- Crohns
- Giardia lamblia
- Surgery
Why might someone have a lack of digestive enzymes?
- Disaccharide deficiency (lactose intolerance)
- Bacterial overgrowth
What is the pathophysiology of coeliac disease?
- Gliadin in gluten (which is toxic) is usually destroyed by IgA
- In coeliacs the gliandin IgA complex binds to transferrin receptors and pass through the epithelium
- Gliadin is then phagocytosed by macrophages in lamina propriety and presented on MHCII
- T cells produce cytokines and cause inflammatory cascade
- Mucosa of the bowel is destroyed
Which area of the bowel is predominantly effected in coeliac disease?
The proximal small bowel
What is absorbed in the proximal small bowel?
B12, folate and iron
What does inadequate absorption of B12, folate and iron result in?
Anaemia
What are the risk factors of coeliac disease?
- Having other autoimmune conditions e.g type 1 diabetes, thyroid disease or sjorgrens
- IgA deficiency
- Breast feeding
Age of introduction to gluten into diet - Rotavirus infection
What are the signs of coeliac disease?
- Stinking stools / fatty stools (steatorrhoea)
- Nausea and vomiting - not IBD IBS
- Diarrhoea
- Abdominal pain
- Bloating
- Angular stomatitis (inflammation of one or both corners of mouth)
- Weight loss
- Fatigue
- Anaemia
- Osteomalacia
Is coeliac disease always symptomatic?
No in a third of cases it is a silent disease and only detected on routine blood tests - presents with a raised MCV (macrocytic anaemia)
What is the gold standard diagnosis for coeliac disease?
Duodenal Biopsy
What would you see on a duodenal biopsy in coeliac disease?
See villous atrophy, crypt hyperplasia and increased intraepithelial WCC - seen histologically
What would you see in a FBC in someone with coeliac disease?
- Low Hb
- Low B12
- Low Ferritin
What serum antibody testing can be done in a patient with coeliac disease and in what cases would this not be specific?
Testing for IgA antibodies. This can present a false negative in some other conditions that are also associated with IgA
