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of Child Neurology

Association Between Infantile Spasms and Nonaccidental Head Injury
Ala Birca, Guy D'Anjou and Lionel Carmant
J Child Neurol published online 11 April 2013
DOI: 10.1177/0883073813483901
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Brief Communication

Association Between Infantile Spasms
and Nonaccidental Head Injury

Journal of Child Neurology
00(0) 1-3
ª The Author(s) 2013
Reprints and permission:
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DOI: 10.1177/0883073813483901
jcn.sagepub.com

Ala Birca, MD, PhD1, Guy D’Anjou, MD1, and
Lionel Carmant, MD1

Abstract
Infantile spasms constitute a severe epileptic encephalopathy of infancy with poor long-term developmental outcome. Many
diverse etiologies have been associated with infantile spasms, but the pathophysiological process is still not fully understood.
We describe 2 cases of previously healthy 1- and 3-month-old infants who suffered a nonaccidental head injury with extensive
cerebral lesions. Both presented with acute focal seizures rapidly controlled with phenobarbital. Nevertheless, they developed
infantile spasms after a latency period of 3-4 months. Spasms were rapidly controlled with vigabatrin. Both children manifested
with developmental delay, either exacerbated (case 1) or elicited (case 2) by infantile spasms. Our report highlights nonaccidental
head injury as a risk factor for developing infantile spasms following a seizure-free latency period. A better understanding of the
pathophysiology linking accidental brain trauma with infantile spasms could lead to more effective neuroprotective strategies. In
the meantime, increased awareness and follow-up are warranted.
Keywords
infantile spasms, pathophysiology, epilepsy, nonaccidental head injury, West syndrome
Received February 21, 2013. Received revised March 2, 2013. Accepted for publication March 3, 2013.

Infantile spasms constitute a severe epileptic encephalopathy
of infancy with poor long-term developmental outcome. The
pathophysiology of infantile spasms is still not fully understood. A variety of underlying pathologies and risk factors have
been associated with infantile spasms,1 although all these
patients manifest with similar clinical seizures and electroencephalographic patterns. Although animal models have improved
our understanding, they have not yet been able to adequately
reproduce certain aspects of the disorder.2,3 A study of infants
with acquired brain injuries and infantile spasms that are well
characterized may therefore provide further insights into the
pathophysiological processes involved and lead to the development of new models to study the disorder. In this report, we
describe 2 cases of previously normal infants who presented
with nonaccidental head injury and, after several seizure-free
months, developed infantile spasms and associated developmental delay. We further highlight nonaccidental head injury
as a risk factor for infantile spasms development, increasing the
need for neurological and cognitive follow-up.

at the emergency department with an altered level of consciousness, multifocal seizures, and bilateral retinal hemorrhages. The electroencephalogram (EEG) showed multifocal
ictal discharges. Brain imaging demonstrated multiple subdural
hematomas, small areas of parenchymal contusions, and a
subarachnoid hemorrhage (Figure 1). The skeletal survey and
infectious and metabolic work-up were negative. A diagnosis
of nonaccidental head injury was established based on clinical
and imaging findings. Phenobarbital was started to control the
seizures. Repeat brain magnetic resonance imaging (MRI) on
day 8 showed ventriculomegaly and diffuse brain atrophy more
pronounced over the parieto-occipital regions. After 1 month
with no seizure recurrence, drug therapy was discontinued.
At 5 months, the child was mildly developmentally delayed.
A severe head circumference growth deceleration was noted,
passing from the 50th percentile (40 cm) on initial admission
at 3 months of age to the 15th percentile (41 cm) 2 months later.
On the contrary, body growth (weight and height) continued to

1

Case Reports
Case 1
A previously normal baby boy 3 months of age, who was the
product of an uncomplicated pregnancy and delivery, arrived

Department of Neurology, Sainte Justine Hospital (CHU Sainte-Justine),
University of Montreal, Montreal, Quebec, Canada

Corresponding Author:
Lionel Carmant, Sainte Justine Hospital Research Center, University of Montreal,
3175 Côte Sainte-Catherine, Montreal, QC, H3T 1C5, Canada.
Email: lionel.carmant@umontreal.ca

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2

Journal of Child Neurology 00(0)

Figure 1. Case 1. Axial T2-weighted magnetic resonance imaging on day
3 of admission to the emergency department. Image shows subacute subdural hematomas at the level of posterior fossa and temporal poles.

Figure 2. Case 2. Axial T1-weighted magnetic resonance imaging on
day 2 of admission to the emergency department. Image shows panhemispheric bilateral subdural hematomas and extensive encephaloclastic lesions at the level of the frontal and temporal regions.

follow the 50th percentile. Routine EEG showed no epileptic
discharges.
Infantile spasms were first observed at the age of 6 months.
Within 2 weeks of their onset, the child lost all previous interest
in environmental stimuli, which led to medical attention. EEG
confirmed the presence of hypsarrhythmia. Vigabatrin was able
to arrest the spasms within 3 days of treatment. Control EEG 2
weeks later showed persistent interictal discharges but no hypsarrhythmia. Currently at the age of 5 years, the child remains
microcephalic (45.5 cm, far below the 2nd percentile), with
body growth roughly following the 15th-25th percentiles, but
now with severe developmental delay, poor eye contact, and
mild spasticity. He is able to walk with help and speak in 2-3
word sentences. He is seizure-free but remains on clobazam
due to the presence of focal epileptiform discharges on EEG
and the parent’s refusal to wean medication.

MRI demonstrated multiple subdural hematomas, subarachnoid and intraventricular hemorrhage, an occipital bone fracture and areas of encephalomalacia in the left frontal and
temporal regions (Figure 2). No abnormalities were detected
on the skeletal survey, cardiac and abdominal ultrasounds, or
infectious and metabolic work-up. The coagulation profile was
normal. A diagnosis of nonaccidental head injury was made
and seizures controlled with phenobarbital. At age 4 months,
phenobarbital was discontinued. No further seizures were
noted, but as the EEG still recorded very active multifocal
epileptic discharges, the infant was started on clobazam. The
infant was still achieving developmental milestones according
to chronological age. Head circumference growth remained
stable over this 3-month period, going from 40 cm (98th percentile) on initial presentation to 45.2 cm (99th percentile),
accompanied by a slight acceleration of body growth from the
60th to the 85th percentile for height and 50th to 97th percentile
for weight. No clinical signs or symptoms of intracranial hypertension were noted. Follow-up MRI showed enlargement of
subarachnoid spaces and ventriculomegaly.
Infantile spasms with hypsarrhythmia on EEG was first
noted at the age of 5 months. Vigabatrin administration
achieved rapid control of spasms and was tapered after 6
months of use. Subsequent EEGs showed no hypsarrhythmia

Case 2
A previously normal baby boy 1 month of age, who was the
product of an uncomplicated pregnancy and delivery, presented
to the emergency department with irritability, repeated rightsided partial seizures and, on examination, left retinal hemorrhaging. The EEG showed multifocal epileptic activity. Brain

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Birca et al

3

but persistent multifocal epileptic discharges. At last followup, the child was 14 months old with no seizure recurrence
on clobazam. Head circumference was continuing to follow the
99th percentile, with normal body growth around the 85th
percentile for both weight and height. He was mildly developmentally delayed, able to crawl and babble, but unable to bear
weight on his legs.

Discussion
Chronic epilepsy occurs in about 20% of nonaccidental head
injury survivors.4 The incidence of infantile spasms in that
population is not really known. Many prenatally or perinatally
acquired brain lesions have been associated with the development of infantile spasms, but none have been shown to directly
precipitate them. In our 2 patients, infantile spasms manifested
within 3-4 months of a cerebral insult, in previously healthy
infants with no other identifiable risk factor and despite well
controlled focal seizures. This time frame was in line with the
one found by Guggenheim et al, which ranged from 6 weeks to
11 months.5 Like neonatal hypoxic-ischemic encephalopathy,
infantile spasms seemed to manifest only after a latency period
during which neuronal network changes accumulate. Although
our data did not allow us to establish a definite mechanism,
they did support a role for traumatic brain injury in the development of symptomatic infantile spasms. They also demonstrated their responsiveness to vigabatrin, as described in the
symptomatic model of infantile spasms.6,7
Studies have described both structural and functional cortical abnormalities in patients with infantile spasms, suggesting a
predilection for posterior brain areas.8,9 However, though our 2
patients had extensive cerebral lesions, case 2 showed no
posterior predominance. According to the developmental
desynchronization model,3 an unbalanced maturational pattern
occurring within a critical developmental window could result
in dysfunctional interactions between abnormal cortical areas
and subcortical structures, regardless of lesion location, thus
precipitating infantile spasms. Our data are consistent with
this hypothesis.
A better understanding of the pathophysiology underlying
infantile spasms development in nonaccidental head injury
could lead to advances in neuroprotective or preventative
strategies. This report highlights nonaccidental head injury as
a risk factor for developing infantile spasms following a
seizure-free latency period. Although no significant delay to
diagnosis (< 1 month) was observed in our patients, health care
professionals should heighten awareness in caregivers of the
risk for young children with nonaccidental head injury for
developing a form of epilepsy as severe as infantile spasms,
with cognitive sequelae. Furthermore, increased neurological
follow-up despite cessation of focal seizures is warranted in
nonaccidental head injury.

Acknowledgements
The authors are grateful to Danielle Buch, medical writer/editor at the
Applied Clinical Research Unit of the Sainte-Justine Research Center,
for critical revision of the manuscript as well as editing.

Author Contributions
AB reviewed the patients’ charts and wrote the first draft of the manuscript. GD reviewed the patients’ charts. LC assisted with the interpretation of the patient data and revised and approved the final
manuscript.

Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to
the research, authorship, and/or publication of this article.

Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.

Ethical Approval
The review of all charts was approved by our institutional review
board.

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2001;23(7):533-538.
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