Flashcards in Met: PBL 1 (Coeliac Disease) Deck (30):
What is haematocrit?
Ratio of erythrocytes to total blood volume
What is mean corpuscular volume (MCV)?
The average volume of red blood cells
What is ferritin?
Protein which stores iron in the tissues
What is folate?
A B vitamin vital in the synthesis of fatty acids
What is the role of alkaline phosphatase?
What is the role of zonulin?
Acts to disassemble the actin filament associated with tight junctions; enteric bacteria and gliadin are the most potent stimulators
What is a low haemoglobin level indicative of?
What is a low haematocrit level indicative of?
Few red blood cells in the blood volume and therefore anaemia
What are low ferritin levels indicative of?
Iron-deficiency as this protein is involved in the storage of iron
What is a high MCV indicative of?
Macrocytic anaemia - implicated in folate or B12 deficiency anaemia
Why may someone with coeliac disease have a low serum calcium level?
Unable to absorb enough calcium in the small intestine due to the absence of villi (blunting)
What is the consequence of being unable to absorb enough calcium (as implicated in coeliac disease)?
Bones will be undergoing degradation to increase serum calcium levels, and if there is insufficient calcium to facilitate calcium deposition by osteoblasts then bone will be gradually degraded leading to weak bones as seen in Rickets/Osteomalacia
What is the relationship between serum phosphate and serum calcium?
As one rises, the other one falls
What is the role of serum phosphate?
Controls osteocytes and osteoblast's apoptosis so is regulatory in the process of bone degradation
What symptoms may low folate levels cause?
Fatigue, depression, pins and needles
What may high levels of alkaline phosphatase indicate?
Bone disease as this enzyme is produced by bone in response
Why may albumin levels bee checked in cases of anaemia?
Albumin is involved in carrying molecules in the blood, and this is to ensure that the liver is functioning effectively as it produces these molecules
Why are total IgA antibody levels assessed in coeliac disease diagnosis?
Some individuals have an IgA deficiency and therefore have IgG antibodies to gliadin instead, and therefore by ensuring they have IgA antibodies before prevents a false-negative test
What antibodies are present in coeliac disease?
Anti-endomysium and IgA anti-tTG antibodies
What is osteomalacia?
Softening of the bones in adults due to defective bone mineralisation, commonly caused by insufficient calcium (Ca2+) absorption in the small intestine
Why is a biopsy taken to confirm the diagnosis of coeliac disease?
To ensure that there is nothing else going on and that dietary changes will resolve the issue alone
What would you see histologically in a jejunal biopsy of someone with coeliac disease?
Flattening/blunting of mucosal surface, many lymphocytes in lamina propria, sparse brush border and cuboidal rather than columnar epithelia, crypt hyperplasia
Why may an individual not be diagnosed with coeliac disease until far later on in their life?
If they only have mild coeliac disease whereby their body can still absorb most of the nutrients so have no immediate side effects/symptoms, however, there are complications that arise from this untreated malabsorption such as osteomalacia
Name and briefly describe the 3 structures making up the intestinal mucosa
Simple columnar epithelia - at the surface of the lumen with microvilli
Lamina propria - loose connective tissue (areolar CT)
Muscularis mucosae - layer of deep smooth muscle beneath
What is the main gluten component that is destructive to the small intestinal mucosa?
How would the duodenum appear in endoscopy in a coeliac patient?
There will be reduced duodenal folds
What is the treatment of coeliac disease?
Gluten free diet; free from rye, barley and wheat
What bacteria causes Whipple's disease?
What are the symptoms of Whipple's disease?
Diarrhoea, steatorrhea, abdominal pain, joint pain