The shaken infant syndrome. Shaking alone may not be responsible for damage

Shaken baby syndrome: a common variant of non-accidental head injury in infants

BACKGROUND

Recent cases of child abuse reported in the media have underlined the importance of unambiguous diagnosis and appropriate action. Failure to recognize abuse may have severe consequences. Abuse of infants often leaves few external signs of injury and therefore merits special diligence, especially in the case of non-accidental head injury, which has high morbidity and mortality.

METHODS

Selective literature review including an overview over national and international recommendations.

RESULTS

Shaken baby syndrome is a common manifestation of non-accidental head injury in infancy. In Germany, there are an estimated 100 to 200 cases annually. The characteristic findings are diffuse encephalopathy and subdural and retinal hemorrhage in the absence of an adequate explanation. The mortality can be as high as 30%, and up to 70% of survivors suffer long-term impairment. Assessment of suspected child abuse requires meticulous documentation in order to preserve evidence as well as radiological, ophthalmological, laboratory, and forensic investigations.

CONCLUSIONS

The correct diagnosis of shaken baby syndrome requires understanding of the underlying pathophysiology. Assessment of suspected child abuse necessitates painstaking clinical examination with careful documentation of the findings. A multidisciplinary approach is indicated. Continuation, expansion, and evaluation of existing preventive measures in Germany is required.

Perpetrator accounts in infant abusive head trauma brought about by a shaking event

OBJECTIVE

To analyze perpetrator and medical evidence collected during investigations of infant abusive head trauma (IAHT), with a view to (a) identifying cases where injuries were induced by shaking in the absence of any impact and (b) documenting the response of infant victims to a violent shaking event.

METHOD

A retrospective study was undertaken of IAHT cases investigated by the Queensland Police Service over a 10-year period. Cases of head trauma involving subdural and/or subarachnoid hematoma and retinal hemorrhages, in the absence of any evidence of impact, were defined as shaking-induced. Perpetrator statements were then examined for further evidence to support the shaking hypothesis and for descriptions of the victim's immediate response to a shaking event.

RESULTS

From a total of 52 serious IAHT cases, 13 (25%) were found to have no medical or observer evidence of impact. In 5 of those 13 cases, there was a statement by the perpetrator to the effect that the victim was subjected to a shaking event. In several cases both with and without evidence of associated impact, perpetrator accounts described an immediate neurological response on the part of the victim.

CONCLUSION

The study confirms that IAHT resulting in death or serious neurological impairment can be induced by shaking alone. In cases where the infant's medical condition was adequately described, the symptoms of head injury presented immediately.

Bruising in non-accidental head injured children; a retrospective study of the prevalence, distribution and pathological associations in 24 cases

Non-accidental head injury, be it shaking, impact(s) or a combination of the two, is characterised by subdural and/or subarachnoid haemorrhages with retinal haemorrhages, but minimal or absent external cranio-facial trauma. The classical assault scenario depicts the infant being gripped around the head, face, chest and abdomen and shaken or being gripped by a limb and swung. This gripping might be expected to leave physical evidence in the form of bruising. A study was undertaken to establish the prevalence, distribution and pathological association of external bruising in 24 cases of fatal non-accidental head injury in children. At autopsy, 17 cases had new external bruises, 15 old external bruises and 13, a combination of both. However, seven (29%) cases showed no fresh external bruising and five (21%) showed no external bruising at all. Thus, external bruising may be absent in children with fatal intracranial injury. The face was shown to be the commonest site of bruising followed by the forehead and buttocks. Limb, chest and abdominal bruising were found to be uncommon. Retinal haemorrhages were confirmed in 23 (96%) cases. It is hypothesised that bruising, when present, may be a result of abuse in the form of punches and slaps rather than due to gripping during the assault. We discuss why gripping does not necessarily result in external bruising.

Shaken adult syndrome

A 30-year-old Palestinian collapsed when under interrogation by the Israeli General Security Service and was declared brain dead 3 days later. Information on the circumstances and interrogation methods was denied on security grounds. Autopsy disclosed extensive anterior chest and shoulder bruising and acute subdural haemorrhage but no other trauma. On this evidence, violent shaking was postulated as the mechanism of injury. Later, this was admitted by Israeli investigators and corroborated by histopathologically proved diffuse axonal injury and retinal haemorrhages. This is the first reported case of fatal shaken adult syndrome.

Evidence from proton magnetic resonance spectroscopy for a metabolic cascade of neuronal damage in shaken baby syndrome

OBJECTIVE

The purpose of this study was to use proton magnetic resonance spectroscopy (MRS) as a metabolic assay to describe biochemical changes during the evolution of neuronal injury in infants after shaken baby syndrome (SBS), that explain the disparity between apparent physical injury and the neurological deficit after SBS.

METHODOLOGY

Three infants [6 months (A), 5 weeks (B), 7 months (C)] with SBS were examined repeatedly using localized quantitative proton MRS. Examinations were performed on days 7 and 13 (A), on days 1, 3, 5, and 12 (B), and on days 7 and 19 (C) posttrauma. Long-term follow-up examinations were performed 5 months posttrauma (A) and 4.6 months posttrauma (B). Data were compared to control data from 52 neurologically normal infants presented in a previous study.

RESULTS

Spectra from parietal white matter obtained at approximately the same time after injury (5 to 7 days) showed markedly different patterns of abnormality. Infant A shows near normal levels of the neuronal marker N-acetyl aspartate, creatine, and phosphocreatine, although infant C shows absent N-acetyl aspartate, almost absent creatine and phosphocreatine, and a great excess of lactate/lipid and lipid. Analysis of the time course in infant B appears to connect these variations as markers of the severity of head injury suffered in the abuse, indicating a progression of biochemical abnormality. The principal cerebral metabolites detected by MRS that remain normal up to 24 hours fall precipitately to approximately 40% of normal within 5 to 12 days, with lactate/lipid and lipid levels more than doubling concentration between days 5 and 12.

CONCLUSIONS

A strong impression is gained of MRS as a prognostic marker because infant A recovered although infants B and C remained in a state consistent with compromised neurological capacity. Loss of integrity of the proton MR spectrum appears to signal irreversible neurological damage and occurs at a time when clinical and neurological status gives no indication of long-term outcome. These results suggest the value of sequential MRS in the management of SBS.