Abusive head trauma — formative SAQs

SAQ 1 (10 marks)

A four-month-old boy is brought to the emergency department by his mother, who says he "rolled off the bed" onto a carpeted floor about an hour ago. He has been irritable and vomiting, and is now limp and grunting. On examination his GCS is 11, his anterior fontanelle is full, and he has two small bruises on his left ear and trunk. A non-contrast CT head shows a thin inter-hemispheric subdural haemorrhage and diffuse cerebral oedema. There is no history of seizures, no bleeding disorder, and no prior medical history. [1] [4]

1. Give your immediate resuscitation and safeguarding actions, and the further investigations you would arrange. (4) [1]
2. State the features of this presentation that increase the probability of abusive head trauma, naming the relevant evidence. (3) [3] [4]
3. Describe how you would manage the siblings and household contacts, and what you would tell the family. (3) [5]

Model answer — SAQ 1

(1) Resuscitation and safeguarding (4). Resuscitate the brain: protect the airway, breathing and circulation; treat seizures and raised intracranial pressure with neuroprotection, head positioning and urgent neurosurgical and intensive-care input, guarding against hypoxia, hypotension and hypoglycaemia. Run safeguarding from minute zero: inform the consultant and the child-protection team, do not discharge the child or allow him to return to the care of a suspected perpetrator, preserve clothing and evidence, and make the mandatory report. Arrange MRI brain within days to map and date the injury, a full skeletal survey to protocol with a repeat at about eleven to fourteen days, dilated ophthalmology with imaging, and a laboratory occult-injury screen (coagulation, full blood count, vitamin-K history, liver and pancreatic markers, urinalysis, and infection and toxicology screens). Document every finding and every history account contemporaneously. [1] [2]

(2) Features raising the probability (3). The developmentally implausible history — a four-month-old cannot reliably roll, and a short fall onto carpet does not cause a thin inter-hemispheric subdural bleed with cerebral oedema; the encephalopathy out of proportion to the offered mechanism; the bruising on the ear and trunk in a non-mobile infant (TEN-4); and the injury pattern of inter-hemispheric subdural haemorrhage with oedema. The Maguire pooled analysis and the Piteau radiographic systematic review define the discriminating features, and the PediBIRN screen (here, suspected encephalopathy, severe head injury and ear/torso bruising) flags likely AHT. [3] [4]

(3) Contacts and family (3). Screen siblings and household contacts for occult injury through the child-protection team — history, examination, and imaging as age-appropriate — because the Lindberg study showed a real prevalence of abusive injuries in contacts of physically abused children. Treat the family with respect and without accusation, explaining that the role of the team is to investigate and protect, keep the child safe, and complete a careful, documented assessment; do not disclose conclusions before the multidisciplinary case conference. [5]

SAQ 2 (10 marks)

A six-week-old infant is found, on cranial ultrasound done for a large head circumference, to have a small subdural collection. She is neurologically normal, feeding well, born by normal vaginal delivery, and has no bruises. Her parents are anxious and ask whether this means the baby has been shaken. [1] [6]

1. Outline your differential diagnosis and the focused workup you would arrange. (4) [1]
2. Explain the role of the "triad" in the diagnosis of AHT, and the RCPCH position on its use. (3) [6]
3. Describe how you would present your assessment to the family and to the child-protection team. (3) [1]

Model answer — SAQ 2

(1) Differential and workup (4). The differential includes birth-related subdural collection (common, usually asymptomatic, resolves in weeks, consistent with the vaginal delivery), a bleeding disorder (vitamin-K deficiency bleeding, haemophilia, rare factor deficiencies), a metabolic or genetic mimic such as glutaric aciduria type 1 (subdural collection with macrocephaly) or Menkes disease, and inflicted injury. The workup is a careful multi-source history, a full examination including dilated ophthalmology (retinal haemorrhages here would shift the probability markedly), an MRI brain to characterise and date the collection, a coagulation and full-blood-count screen with a vitamin-K history, a metabolic screen where macrocephaly or other features suggest it, and a skeletal survey because occult inflicted injury must be excluded. A medical mimic does not exclude abuse, so the team weighs the whole picture. [1]

(2) The triad and the RCPCH position (3). The "triad" — subdural haemorrhage, retinal haemorrhage and encephalopathy — is highly suggestive of inflicted injury when mimics are excluded and the history is implausible, but it is not a rigid diagnostic formula and no single finding diagnoses AHT alone. The RCPCH position is that the triad must be used with caution: the paediatrician presents a probability grounded in the whole clinical picture (mechanism, injury pattern, mimics, context), not a verdict, and never overstates the certainty of any one finding — the lesson reinforced by the history of overturned convictions. In this well infant with an isolated collection and no encephalopathy or retinal haemorrhage, the triad does not apply and the probability is genuinely indeterminate until the workup completes. [6]

(3) Presenting the assessment (3). Be honest, calm and non-judgemental with the family: explain that a subdural collection has several possible causes, that a careful assessment is needed, and that the team's duty is to keep the baby safe while it is completed — not to accuse. To the child-protection team, present the structured findings, the mimics considered and the workup arranged, and an explicit statement of the current probability (here, indeterminate pending investigation). Arrange a safe disposition, neurodevelopmental follow-up, and a clear multidisciplinary review of the completed assessment before any conclusion is communicated. [1]