PLAB 1 Paediatrics — Questions and Answers
Question 1: A 3-year-old child presents to A&E with a barking cough, stridor at rest, and mild chest wall recession. According to NICE guidelines, what is the most appropriate initial management?
- IV antibiotics and admission to intensive care
- Single dose of oral dexamethasone (0.15 mg/kg) (Correct answer)
- Immediate intubation
- Salbutamol nebuliser
Correct answer: Single dose of oral dexamethasone (0.15 mg/kg)
This presentation is consistent with moderate croup (viral laryngotracheobronchitis). NICE recommends a single dose of oral dexamethasone (0.15 mg/kg) for all children presenting with croup. Nebulised adrenaline is reserved for severe croup with significant respiratory distress.
Question 2: A 6-week-old infant is brought to the GP with projectile vomiting after every feed for the past week. On examination, a small olive-shaped mass is palpable in the right upper quadrant. What is the most likely diagnosis?
- Gastro-oesophageal reflux
- Pyloric stenosis (Correct answer)
- Intussusception
- Duodenal atresia
Correct answer: Pyloric stenosis
Pyloric stenosis typically presents at 2-8 weeks of age with progressive projectile non-bilious vomiting. A palpable 'olive' in the right upper quadrant is the classic examination finding. It is more common in firstborn males. Diagnosis is confirmed by ultrasound and treated with Ramstedt's pyloromyotomy.
Question 3: A 2-year-old child presents with a 5-day history of high fever (>39°C), bilateral non-purulent conjunctival injection, strawberry tongue, cervical lymphadenopathy, and a polymorphous rash. What is the most likely diagnosis?
- Scarlet fever
- Kawasaki disease (Correct answer)
- Measles
- Meningococcal septicaemia
Correct answer: Kawasaki disease
Kawasaki disease requires fever for ≥5 days plus at least 4 of 5 criteria: bilateral conjunctival injection, oral mucosal changes (strawberry tongue, cracked lips), polymorphous rash, cervical lymphadenopathy, and extremity changes. Treatment with IV immunoglobulin and aspirin reduces the risk of coronary artery aneurysms.
Question 4: A 4-year-old child is brought to A&E with sudden onset of drooling, high fever, and sitting in a tripod position. The child appears toxic and has a muffled voice. What is the most likely diagnosis and immediate priority?
- Croup — administer nebulised adrenaline
- Acute epiglottitis — do not examine the throat; call senior anaesthetist for airway management (Correct answer)
- Peritonsillar abscess — arrange incision and drainage
- Viral pharyngitis — prescribe paracetamol and discharge
Correct answer: Acute epiglottitis — do not examine the throat; call senior anaesthetist for airway management
Acute epiglottitis presents with the 4 D's: Drooling, Dysphagia, Dysphonia, and Distress. The child often adopts a tripod position. It is a life-threatening airway emergency. Do NOT examine the throat (risk of complete airway obstruction). Call a senior anaesthetist immediately for controlled airway management.
Question 5: According to the UK immunisation schedule, at what age should a child receive their first dose of the MMR vaccine?
- 6 months
- 12 months (on or after their first birthday) (Correct answer)
- 18 months
- 2 years
Correct answer: 12 months (on or after their first birthday)
The UK childhood immunisation schedule recommends the first dose of MMR vaccine at 12 months of age (on or after the first birthday). The second dose is given at 3 years 4 months (pre-school booster). MMR protects against measles, mumps, and rubella.
Question 6: A 9-month-old infant presents with paroxysmal colicky abdominal pain, drawing up of the legs, a sausage-shaped mass in the right upper quadrant, and 'redcurrant jelly' stools. What is the most likely diagnosis?
- Appendicitis
- Intussusception (Correct answer)
- Meckel's diverticulum
- Hirschsprung's disease
Correct answer: Intussusception
Intussusception typically presents in infants aged 6-18 months with paroxysmal colicky pain (episodes of screaming with legs drawn up), a sausage-shaped mass (usually RUQ), and redcurrant jelly stools (blood and mucus). First-line treatment is air or contrast enema reduction.
PLAB 1 Paediatrics
A 3-year-old child presents to A&E with a barking cough, stridor at rest, and mild chest wall recession.
According to NICE guidelines, what is the most appropriate initial management?