Lecture 32 Flashcards
Describe how Pippa first was recognised with coeliacs?
Pippa:
- Breastfed till 11mths, started solid. Within eating solids, starting getting grumpy, stools changed in colour and smell.
- Fat stomach and tiny bottom and lots of rash.
What is coeliacs disease?
Abnormal lining of the small bowel that improves after excluding wheat from the diet.
How was coeliacs diagnosed in the past?
When there was significant weight loss and multiple problems with absorption of nutrients (vitamins). The diagnosis was confirmed by a small bowel biopsy.
How else was coeliacs diagnosed in the past?
Blood tests using gliadin antibody tests, however there were problems with false positives and negatives.
What is an “iceberg” analogy of coeliac disease?
The overt reverse disease is at the top and mild or silent disease forming the majority below sea level.
What is the cause of coeliac disease?
There is a strong genetic component to the disease. 1:10 1st degree relatives will have coeliac disease. There are two genes: HLA DQ2 and DQ8. Common in people with northern european ancestry.
What is the pathogenesis of coeliac disease?
Gluten exposure required. Abnormal cellular and humeral response to gain ( a component of gluten) probably causes mucosal damage. Exposure of immunologically active epitope requires tissue transglutaminase (extracellular matrix enzyme).
What is the pathology of the coeliac disease?
Villous atrophy and hypertrophy of crypts, intraepithelial lymphocytes.
What is the pathophysiology of the coeliac disease?
Loss of brush border enzymes, loss of stimulus for pancreatic and bile secretion (low pancreozymin and secretin), exudation of protein across denuded mucosa.
Describe the antibodies affairs the enzyme transglutaminase?
They’re not cytotoxic. They are a by-product of the inflammation and damage caused by activated immune cells.
What is the Marsh cycle?
Stage 0: normal mucosa.
Stage 1: Increased number of intra-epithelial lymphocytes (IELs).
Stage 2: Crypt proliferation.
Stage 3: Partial or complete villous atrophy and crypt hypertrophy.
Stage 4: Hypoplasia of the SI architecture.
How does Coeliacs present in children?
1) Failure to thrive.
2) Diarrhoea, irritable and poor appetite.
3) May present as fe deficiency, short stature, abdominal distension or part of family screening.
How does coeliacs present in adults?
Silent during childhood.
1) Abdominal bloating and discomfort.
2) Iron deficiency with or with our anaemia is suggestive.
3) Additional finding of folate deficiency makes diagnosis highly likely.
4) Screening relatives:
-1:10 first degree relatives will be positive and 1:35 second degree relatives.
-Up to 25% of people with coeliacs are identified by screening method.
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What are coeliac antibodies?
1) Anti-TTG (tissue transglutaminase antibody) IgA - recommended.
2) Anti-EMA (endomysial antibody) IgA.
3) Anti-DGP (deaminated gliadin peptide) IgA.
Why can’t Anti-gliadin antibodies be used anymore?
Due to poor accuracy; replaced by newer generation deaminated form anti-DGP. The antibodies tested able by the lab are IgA, so may be falsely negative in IgA deficiency. If IgA deficiency, will need IgG form of the above antibodies.
