Vomiting and Malabsorption Part 2

Question 1

How much fluid enters the duodenum daily and what volume of this reaches the colon?

Answer 1

9L fluid enters duodenum
1.5L gets to colon
<200ml lost in faeces

Question 2

What features of the small intestine improve absorption?

Answer 2

Mucosal folds and villi

Question 3

What does the small intestine excrete?

Answer 3

Water for fluidity/enzyme transport/absorption
Ions e.g. duodenal HCO3-
Defense mechanism against pathogens/harmful substances/antigens

Question 4

What is the definition of chronic diarrhoea?

Answer 4

4 or more stools per day For more than 4 weeks

<1 week: acute diarrhoea
2 to 4 weeks: persistent diarrhoea

Question 5

What are the three general causes of diarrhoea?

Answer 5

Motility disturbance
Active secretion
Malabsorption of nutrients

Question 6

What are the types of motility disturbance?

Answer 6

Toddler Diarrhoea

Irritable Bowel Syndrome

Question 7

What are the types of active secretion?

Answer 7

Acute Infective Diarrhoea
Inflammatory Bowel Disease

Question 8

What are the types of malabsorption of nutrients (osmotic)?

Answer 8

Food Allergy
Coeliac Disease
Cystic Fibrosis

Question 9

What is osmtoic diarrhoea?

Answer 9

Movement of water into the bowel to equilibrate osmotic gradient

Usually a feature of malabsorption:

• Enzymatic defect (eg. Secondary lactase deficiency)
• Transport defect ( eg glucose galactose transporter defect)

Question 10

What is secretory diarrhoea?

Answer 10

Classically associated with toxin production from Vibrio cholerae and enterotoxigenic Escherichia coli
-In cholera, can lose 24L per day!

Intestinal fluid secretion predominantly driven by active Cl- secretion via CFTR

Question 11

What are the components of a diarrhoea history?

Answer 11

Age at onset
Abrupt/gradual onset
Family history
Travel history/local outbreaks
Nocturnal defecation suggests organic pathology

Question 12

What are the examinations/investigations carried out in diarrhoea?

Answer 12

Consider growth and weight gain of child

Faeces analysis

• Appearance
• Stool culture
• Determination of secretory vs. osmotic

Question 13

How do you differentiate between osmotic and secretory diarrhoea?

Answer 13

OSMOTIC VS. SECRETORY

Osmotic:

• Small
• Large osmotic gap
• Low sodium, potassium and chloride
• Low pH
• Stool reducing substance positive

Secretory:

• Large
• Small osmotic gap
• High sodium, potassium and chloride
• High pH
• Stool reducing substance negative

Question 14

What can cause fat malabsorption?

Answer 14

Pancreatic disease

Hepatobiliary disease

Question 15

What are the types of pancreatic disease?

Answer 15

Diarrhoea due to lack of lipase and resultant steatorrhoea

Classically cystic fibrosis

Question 16

What are the types of hepatobiliary disease?

Answer 16

Chronic liver disease

Cholestasis

Question 17

What is Shwachman-Diamond syndrome?

Answer 17

Pancreatic insufficiency and bone marrow dysfunction

98% have neutropenia

Question 18

What is coeliac disease?

Answer 18

“Gluten-sensitive enteropathy”

Question 19

How does coeliac disease present?

Answer 19

Abdominal bloatedness
Diarrhoea
Failure to thrive
Short stature
Constipation
Tiredness
Dermatitis herpatiformis

More common in children with other autoimmune conditions like IDDM and first degree relatives

Question 20

What serological tests are carried out for suspected coeliac disease?

Answer 20

Anti-tissue transglutaminase (high sensitivity)
Anti-endomysial ( high specificity)
Check Serum IgA
Concurrent IgA deficiency in 2% may result in false negatives

Question 21

What is the gold standard for diagnosing coeliac disease?

Answer 21

Duodenal biopsy

Looks red and inflamed

Question 22

What genetic testing may be used for coeliac disease?

Answer 22

HLA DQ2, DQ8

Question 23

How may coeliac disease appear on histology?

Answer 23

Lymphocytic infiltration of surface epithelium,
Partial/total villous atrophy
Crypt hyperplasia

Question 24

What are the ESPGHAN/BSPGHAN guidelines for diagnosing coeliac disease in children?

Answer 24

Symptomatic children
Anti TTG >10 times upper limit of normal (Anti-tissue transglutaminase
Positive anti endomysial antibodies
HLA DQ2, DQ8 positive

If all the above are present then diagnoses made without biopsy

If any of the above are not present then proceed to endoscopy

Question 25

How is coeliac disease managed?

Answer 25

• Gluten-free diet for life
• Gluten must not be removed prior to diagnosis as serological and histological features will resolve
• In very young <2yrs, re-challenge and re-biopsy may be warranted
• Increased risk of rare small bowel lymphoma in untreated

Question 26

Summary

Answer 26

Vomiting in infants and children can be due to GI and non GI causes.
Gastroesophageal reflux is common in infants and usually resolves with age
Coeliac disease is a common cause for malabsorption in children
In a well toddler, undigested vegetables in the stool suggests chronic non-specific ‘toddlers’ diarrhea and it improves with age.