Vomiting and Diarrhoea

Question 1

Describe the different types of diarrhoea and give the most common cause(s) of each

Answer 1

Osmotic - malabsorption
Secretory - inflammation
Motility - toddler’s diarrhoea, IBS

Question 2

Give a common cause of malabsorption in children

Answer 2

Coeliac disease

- autoimmune (not allergy) reaction to gluten

Question 3

What causes fat malabsorption?

Answer 3

Pancreatic disease e.g. cystic fibrosis

Hepatobiliary disease e.g. chronic liver disease, cholestasis

Question 4

What are the symptoms of coeliac disease?

Answer 4

• Abdominal distension (bloating)
• Diarrhoea
• Failure to thrive
• Short stature
• Constipation
• Tiredness
• Dermatitis herpatiformis

Question 5

How is coeliac disease diagnosed?

Answer 5

Serology - anti-TGA
Endoscopy
Duodenal biopsy (gold standard)
Genetic testing - HLA-DQ2/DQ8

Question 6

Describe the role of genetic testing in the investigation of coeliac disease in children

Answer 6

Good negative predictor - if the child does not have the associated genes then coeliac is very unlikely to be the diagnosis

Question 7

What are the histological features of intestinal epithelium in coeliac disease?

Answer 7

Lymphocytic infiltration on surface epithelium
Partial/total villous atrophy
Crypt hyperplasia

Question 8

When is a biopsy not required to diagnose coeliac disease in a child?

Answer 8

• Symptomatic children
• Anti TTG >10 times upper limit of normal
• Positive anti endomysial antibodies
• Normal serum IgA
• HLA DQ2, DQ8 positive

Question 9

What is the key differential diagnosis of bilious vomiting?

Answer 9

Bowel obstruction

• intestinal atresia
• intussusception
• malrotation
• ileus

Question 10

What are the most common causes of secretory diarrhoea?

Answer 10

Infection, particularly toxin-production from cholera and E.coli
Inflammatory Bowel Disease