Expanding the Distinctive Neuroimaging Phenotype of ACTA2 Mutations

BACKGROUND AND PURPOSE: Arg179His mutations in ACTA2 are associated with a distinctive neurovascular phenotype characterized by a straight course of intracranial arteries, absent basal Moyamoya collaterals, dilation of the proximal internal carotid arteries, and occlusive disease of the terminal internal carotid arteries. We now add to the distinctive neuroimaging features in these patients by describing their unique constellation of brain malformative findings that could flag the diagnosis in cases in which targeted cerebrovascular imaging has not been performed. MATERIALS AND METHODS: Neuroimaging studies from 13 patients with heterozygous Arg179His mutations in ACTA2 and 1 patient with pathognomonic clinicoradiologic findings for ACTA2 mutation were retrospectively reviewed. The presence and localization of brain malformations and other abnormal brain MR imaging findings are reported. RESULTS: Characteristics bending and hypoplasia of the anterior corpus callosum, apparent absence of the anterior gyrus cinguli, and radial frontal gyration were present in 100% of the patients; flattening of the pons on the midline and multiple indentations in the lateral surface of the pons were demonstrated in 93% of the patients; and apparent "squeezing" of the cerebral peduncles in 85% of the patients. CONCLUSIONS: Because α-actin is not expressed in the brain parenchyma, only in vascular tissue, we speculate that rather than a true malformative process, these findings represent a deformation of the brain during development related to the mechanical interaction with rigid arteries during the embryogenesis

Paediatric MOG antibody-associated ADEM with complex movement disorder: A case report

Myelin oligodendrocyte glycoprotein antibodies (MOG-Abs) are a well-recognized cause of acquired demyelinating syndromes in both adult and children. Despite basal ganglia involvement on imaging, movement disorder is not a cardinal feature. We describe a 2-year-9-month-old girl who presented with severe encephalopathy with aphasia, seizures and a complex movement disorder with dystonic posturing and tonic eye deviation. Neuroimaging revealed subtle asymmetrical predominantly white matter signal changes. MOG-Abs were positive in the serum. Other known pathogenic autoantibodies including N-methyl-D-aspartate receptor antibodies (NMDAR-Abs) were negative. The patient made a complete recovery following 2-week corticosteroid treatment. This case highlights the need for MOG-Ab testing in children with suspected autoimmune encephalopathies

Long-term prognosis after childhood convulsive status epilepticus: a prospective cohort study

Background: The prognosis of convulsive status epilepticus (CSE), a common childhood medical neurological emergency, is not well characterised. We aimed to investigate the long-term outcomes in a cohort of participants who previously had CSE. Methods: In this prospective study, we followed up a population-based childhood CSE cohort from north London, UK (the north London convulsive status epilepticus surveillance study cohort; NLSTEPSS). We collected data from structured clinical neurological assessment, neurocognitive assessment (Wechsler Abbreviated Scale of Intelligence), brain MRI, medical records, and structured interviews with participants and their parents to determine neurological outcomes, with adverse outcome defined as presence of one or more of epilepsy (active or in remission), motor disability, intellectual disability, or statement of special educational needs. We applied multiple imputation to address missing data and performed binary logistic regression analyses on complete-case and imputed datasets to investigate sociodemographic and CSE factors associated with adverse outcomes. Findings: Of 203 survivors (90% of inception cohort), 134 (66%) were assessed at a median follow-up of 8·9 years (IQR 8·2–9·5). The cumulative incidence of epilepsy was 24·7% (95% CI 16·2–35·6), with most (89%) emerging within 18 months after CSE. The cumulative incidence of epilepsy was lower in patients with prolonged febrile seizures (14·3%, 6·3–29·4) and survivors of acute symptomatic CSE (13·3%, 3·7–37·9) than in those of remote symptomatic CSE (45·5%, 21·3–72·0) and unclassified CSE (50·0%, 25·4–74·6). One participant (2·9%, 0·5–14·5) in the prolonged febrile seizures group developed temporal lobe epilepsy with mesial temporal sclerosis. The absence of fever at CSE was the only predictor of incident epilepsy (odds ratio [OR] 7·5, 95% CI 2·25–25·1). Motor and intellectual disability was seen predominantly in participants who had idiopathic and cryptogenic CSE (seven [36·8%, 95% CI 19·1–59·0] and 16 [84·2%, 62·4–94·5] of 19, respectively) a nd remote symptomatic CSE (33 [62·3%, 48·8–74·1] and 40 [75·5%, 62·4–85·1] of 53), and most of these participants had pre-existing disabilities. Pre-existing epilepsy was the only predictor of intellectual disability (OR 8·0, 95% CI 1·1–59·6). 51·5% (95% CI 43·1–59·8) of those followed up had a statement of special educational needs. Interpretation: Childhood CSE is associated with substantial long-term neurological morbidity, but primarily in those who have epilepsy, neurological abnormalities, or both before the episode of CSE. Survivors without neurological abnormalities before CSE have favourable outcomes. Funding: BUPA Foundation, The Academy of Medical Sciences, Wellcome Trust, National Institute for Health Research, and Young Epilepsy