Brain abscess and intracranial suppuration — branching viva

Examiner opening (Examiner)

You are the general paediatric registrar in the emergency department. A nine-year-old boy is brought in with a week of worsening frontal headache and low-grade fever, treated as sinusitis, who this morning is confused and dragging his right leg. His CT is on the screen — a 2.8 cm ring-enhancing left frontal-lobe lesion with oedema and midline shift. Talk me through your immediate assessment and plan. ^[1]

Exemplar opening (Candidate)

This is a febrile child with evolving focal neurology and a ring-enhancing lesion on CT — I am treating this as a suspected brain abscess, which is a neurosurgical emergency. My first priority is resuscitation and the brain. I will assess and secure his airway, breathing and circulation, treat any seizure with a benzodiazepine, and because he is drowsy with midline shift and signs of raised intracranial pressure, I will elevate the head of the bed to 30 degrees and give an osmotic agent — mannitol 0.25–0.5 g/kg IV or hypertonic 3% saline 2–5 mL/kg IV — for impending herniation. I will not perform a lumbar puncture, because a mass lesion is confirmed and it risks herniation. In parallel I will refer urgently to paediatric neurosurgery and infectious diseases, obtain a contrast MRI with gadolinium and diffusion-weighted imaging to characterise and date the lesion, take blood cultures, and arrange aspiration for pus and culture. ^{[1] [2]}