Paeds: Gastroenteritis

Question 1

Definition

Answer 1

Infective diarrhoea and vomiting

Question 2

Causes

Answer 2

Viral: Rotavirus (commonest), adenovirus, calcivirus, corona, astroviruses.

Question 3

Dehydration

Answer 3

• Causes of death in gastroenteritis and its correction is fundamental to treatment
• Total body deficit of NA and water

Question 4

Types of Dehydration

Answer 4

1. Isnatraemic
2. Hyponatraemic dehydration
3. Hypernatraemic dehydration

Question 5

Isnatraemic

Answer 5

• Loss of NA and water are proportional

- Plasma NA remains within normal range

Question 6

Hyponatraemic dehydration

Answer 6

• Na losses exceed those of water
• Plasma NA falls
• Shift in water from extra- to intra-cellular compartments = raised brain volume = sometimes convulsions
• Common in poorly nourished in developing countries

Question 7

Hypernatraemic dehydration

Answer 7

1. Water loss exceeds sodium loss and plasma sodium concentration increased (rare)
2. Results from high insensbile water loss e.g. high fever/hot, dry environment/low-sodium diarrhoea
3. Shift in water form intra-to extra-cellular comaprtments
4. Harder to recognise as less evidence of signs

Question 8

Hypernatraemic dehydration treatment

Answer 8

reduce plasma sodium slowly to avoid convulsions

Question 9

Causes of diarrhoea

Answer 9

• food intolerance

- Antibiotics

Question 10

Causes of bloody diarrhoea:

Answer 10

• Bacterial (less common): campylobacter jejuni. shigella, salmonellae, enterotoxigenic E. coli, cholera
• NEC
• Intussusception
• IBD

Question 11

Post-gastroenteritis Syndrome

Answer 11

• Return of watery diarrhoea - Temporary lactulose intolerance may have developed.

Question 12

Post-gastroenteritis Syndrome treatment:

Answer 12

• Oral rehydration solution for 24h, then, introduction of a normal diet.
• Rarely need to exclude cow’s milk, disaccharides and gluten

Question 13

Toddlers diarrhoea

Answer 13

‘Pea and carrots syndrome’ - presence of undigested vegetables

• results from underlying maturation delay in intestinal motility
• Most grow out of it by 5 yoa.

Question 14

Diarrhoea mild

- Clinical features

Answer 14

• Dry mucous membranes

Question 15

Diarrhoea mild

- Treatment

Answer 15

Short-term substitution of normal feeds with glucose-electrolyte solution.

Question 16

Diarrhoea moderate

- Clinical features

Answer 16

1. 5-10% body weight loss
2. Thirst, restless, lethargic
3. Reduced tears
4. Reduced tissue elasticity
5. Dry mucous membranes
6. CRT: normal/prlonged
7. BP: normal/low
8. urine output: reduced
9. Pulse: Rapid
10. Eyes: sunken
11. Anterior fontanelle: sunken

Question 17

Diarrhoea moderate

Treatment

Answer 17

• Oral rehydration, give 100ml/kg over 6 hrs

- If no improvement give i.v. rehydration

Question 18

Diarrhoea severe

clinical features

Answer 18

• > 10% body weight loss
• Drowsy, cold, sweating
• Tears: absent
• Tissue elasticity:absent
• V.dry mucous membranes
• CRT: prolonged (>2s)
• BP: low/unrecognizable
• Urine output: oliguria
• Pulse: rapid, weak, possibly impalpable
• Eyes: v. sunken
• Anterior fontanelle: v. sunken

Question 19

Diarrhoea severe

Treatment

Answer 19

• I.V. rehydration
• Add plasma chloride to i.v. infusion once urinating
• Shocked then resuscitate with plasma volume expansion
• Monitor: fluid balance, weight, plasma electrolytes

Question 20

Diarrhoea complications

Answer 20

Acute renal failure

Pulmonary oedema

Question 21

Anti-diarrhoea drugs should they be used?

Answer 21

e.g. Loperamide and anti-emetics 
NO because
a. they are ineffective
b. prolonged excretion of bacteria in stools
c. side-effects
d. cost
e. focus attention from oral rehydration