Malabsorption in a child: Coeliac disease Flashcards
Define coeliac disease.
A lifelong gluten-induced enteropathy of the proximal small bowel resulting in malabsorption, which remits completely on gluten withdrawal.
Explain the aetiology/risk factors of coeliac disease.
Permanent sensitivity to the a-gliadin component of the cereal protein gluten. The immunological reaction in the small intestine results in mucosal damage and loss of villi.
Macro: ‘Subtotal villous atrophy’ of the proximal small intestine; mucosa has a smooth flat appearance.
Micro: Increased inflammatory infiltrates of lymphocytes and plasma cells in the lamina propria of the small bowel.
Summarise the epidemiology of coeliac disease.
1% positive coeliac serology (UK data). Only 1/8 cases is currently diagnosed. Recent prevalence studies describe an increase but this may be due to an increase in targeted screening. UK prevalence in first-degree relatives is 5.6–22.5%.
95% of individuals are HLA DQ2 or DQ8 positive.
What are the presenting symptoms of coeliac disease?
Classic history of coeliac disease with symptoms of malabsorption (diarrhoea, steatorrhoea, failure to thrive or weight loss) is now considered to be quite rare. Most patients have milder symptoms of fatigue, irritability, abdominal pain, bloating, indigestion or no symptoms at all. One in four children with CD is diagnosed by targeted screening.
What are the signs of coeliac disease?
Many children will have no abnormal findings on examination.
Classic severe presentation: Miserable, pale, aphthous stomatitis, digital clubbing, abdominal distension, ‘pot-belly’ appearance, buttock wasting, delayed puberty.
Dermatitis herpetiformis: Itchy blisters on elbows, knees, face and buttocks
What are appropriate investigations for coeliac disease?
Offer serological testing to any individual with autoimmune thyroid disease, dermatitis herpetiformis, irritable bowel syndrome, type 1 diabetes or first-degree relatives (parents, siblings or children) with CD.
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Serology: Check IgA level as 2% of individuals with CD will be deficient.
- Antibody directed against tissue transglutaminase (tTGA).
- Antiendomysial antibodies if the result of the tTGA test is equivocal.
- Bloods: Low Hb, low MCV in iron deficiency, high MCV in B12/folate deficiency, low Ca2, low albumin.
- Jejunal biopsy: Gold standard for diagnosis. Classic criterion on jejunal biopsy is flattened smooth mucosa with subtotal villous atrophy. 6.4–9.1% of CD cases have negative serology so biopsy should still be performed if there is clinical suspicion.
If the initial diagnosis is uncertain in children <2 years then a gluten challenge to confirm diagnosis is recommended at 6–7 years or after pubertal growth.
How is coeliac disease prevented?
Continued breastfeeding during weaning onto wheat has been postulated as potentially protective.
What is the management for coeliac disease?
Continued breastfeeding during weaning onto wheat has been postulated as potentially protective.
What are complications associated with coeliac disease?
Osteoporosis and related fractures, 2 lactose intolerance due to damage of the brush border, intestinal lymphoma, bacterial overgrowth, decreased fertility and increased fetal loss/low-birth weight babies. After diagnosis of coeliac disease weight gain leading to obesity is now increasingly being recognised.
What is the prognosis of coeliac disease?
With diet adherence, there is good prognosis.
