PLAB Pediatrics & Child Health Flashcards

A 4-year-old child presents with a widespread purpuric rash, arthritis, colicky abdominal pain, and haematuria. What is the most likely diagnosis?

Answer: Henoch-Schönlein Purpura (IgA vasculitis)

Henoch-Schönlein Purpura (IgA vasculitis) is the most common childhood vasculitis, characterized by the tetrad of palpable purpura (predominantly lower limbs/buttocks), arthritis, colicky abdominal pain, and renal involvement (haematuria).

What is the hallmark ECG finding in complete atrioventricular (AV) block in a neonate?

Answer: Complete dissociation between P waves and QRS complexes

Complete (third-degree) AV block is characterized on ECG by complete dissociation between atrial P waves and ventricular QRS complexes, with the ventricles beating independently at a slow escape rate.

A 3-year-old presents with high fever, drooling, muffled 'hot potato' voice, and reluctance to move the neck. He sits in a tripod position and appears toxic. What is the most dangerous diagnosis to exclude?

Answer: Epiglottitis

Epiglottitis (most commonly due to Haemophilus influenzae type b pre-vaccination era, now Streptococcus/Staphylococcus) is a life-threatening emergency presenting with high fever, drooling, muffled voice, and the tripod position; airway management takes priority.

Which organism is the most common cause of bacterial meningitis in children aged 1 month to 5 years?

Answer: Streptococcus pneumoniae

Streptococcus pneumoniae is the most common cause of bacterial meningitis in children over 1 month of age (along with Neisseria meningitidis), with pneumococcal meningitis carrying a higher mortality and complication rate.

A 7-year-old boy with known asthma presents with a wheeze, respiratory rate of 40/min, SpO2 88% on air, and is unable to complete sentences. What severity of asthma attack is this?

Answer: Life-threatening asthma

Life-threatening asthma in children includes SpO2 <92%, silent chest, cyanosis, poor respiratory effort, exhaustion, or altered consciousness; SpO2 of 88% meets this threshold and requires immediate aggressive management.

What is the recommended maintenance fluid for children in most UK pediatric settings?

Answer: 0.9% NaCl with 5% dextrose

Current NICE guidelines recommend isotonic fluids (0.9% NaCl with 5% dextrose) for pediatric maintenance to reduce the risk of hyponatremia that occurred with hypotonic solutions.