Paediatric Gastroenterology

Question 1

How could you differentiate viral vs bacterial gastroenteritis?

Answer 1

Both would present with:

• watery diarrhoea +/- vomiting
• crampy abdo. pain
• fever
• +/- dehydration

Bacterial GE may also cause:

• dysentry (blood + mucus in stool)
• malaise
• tenesmus

Question 2

Name common organisms causing gastroenteritis.

Answer 2

Viral:

• rotavirus
• norovirus
• enteric adenovirus

Bacterial:

• Salmonella spp.
• Shigella spp.
• E. coli (inc. EHEC)
• Campylobacter jejuni
• Clostridium difficile

Parasites:
- Giardia

Question 3

A 5 year old boy presents with 2 day Hx of: crampy abdo. pain, watery diarrhoea and non-bilious vomiting. He also has coryzal symptoms. What is the likely causative organism?

Answer 3

Rotavirus - often associated with URT symptoms.

Question 4

Which organisms are associated with haemolytic uraemic syndrome? What is the pathophysiolgy of this?

Answer 4

Mainly enterohaemorrhagic E. coli (also Shigella dysenteriae). and Streptococcus pneumoniae).

EHEC produced Shiga toxin which binds endothelial receptors… thrombin + fibrin deposited in microvasculature esp. of CNS, GI tract and kidney… RBC damage/haemolysis + platelet sequestration.

Causes triad of microangiopathic haemolytic anaemia + thrombocytopaenia + AKI.

Question 5

A 15 year old boypresents with increasing weakness in her legs, with difficulty walking, loss of tone and tingling sensations. His parents report she had a 3 day diarrhoeal illness 2 weeks ago. What is the likely diagnosis and what is the causative organism?

Answer 5

Guillain-Barre syndrome as a complication of Campylobacter jejuni gastroenteritis

Question 6

What is reactive arthritis and which organisms is it associated with in the context of gastroenteritis?

Answer 6

Triad of conjunctivitis + urethritis + arthritis (usually oligoarthritis of lower limb)

Typically caused by Salmonella spp., Shigella spp. or Campylobacter jejuni

Question 7

A 3 year old girl presents with diarrhoea lasting for 10 days, abdominal pain and weight loss. Stool cultures were negative for common bacterial agents. Which infection would you suspect and how would you investigate? How would you treat?

Answer 7

Giardiasis (Giardia lamblia)

Stool culture (3 fresh specimens 2-3 days apart) for ova, cysts + parasites.

Tx = metronidazole

Question 8

Under which circumstances would you perform Ix for a patient presenting with suspected gastroenteritis?

Answer 8

If suspecting GE, send stool culture + stool C. difficile toxin if:

• blood/mucus in stool
• recent foreign travel
• immunocompromised child
• septicaemia suspected
• diarrhoea not improved after day 7
• uncertain diagnosis

Question 9

A child with a 3 day history of diarrhoea + vomiting presents to ED. They appear unwell, with a reduced urine output. Peripheral pulses, CRT and BP are normal. How would you manage them initially?

Answer 9

Signs of clinical dehydration.

1. give ORAL REHYDRATING SOLUTION (50 ml/kg over 4 hrs + maintenance) often and in small amounts.
   Continue breast feeding/usual fluids.
2. consider ONDANSETRON if continues to vomit.
3. consider ORS via NG tube if unable to drink/persistent vomiting
4. monitor every 2 hrs - when child is clinically rehydrated, discharge with advice

Question 10

A child with a 3 day history of diarrhoea + vomiting presents to ED. They appear unwell, with a reduced urine output, sunken eyes, tachycardia and reduced skin turgor. Peripheral pulses are weak, CRT is of 5 secs and BP is low. They have a decreased level of consciousness. How would you manage them initially?

Answer 10

They are in clinical shock.

1. Give 20 ml/kg IV bolus of 0.9% NaCl (10 ml/kg in neonate).
2. if remains shocked, repeat bolus.
3. if remains shocked, call CICU

Question 11

Describe your fluid maintenance regime for a paediatric inpatient requiring IV fluids.

Answer 11

0. 9% NaCl + 5% dextrose:
   - 100 ml/kg for 1st 10 kg
   - 50 ml/kg for 2nd 10 kg
   - 20 ml/kg for every kg >20 kg

over 24 hrs