Diagnostic pathway and management of first seizures in infants with Sturge-Weber syndrome.

AIM: Sturge-Weber syndrome (SWS) is a rare neurocutaneous syndrome, frequently associated with pharmaco-resistant, early-onset epilepsy. Optimal seizure control is paramount to maximize neurodevelopment. METHOD: A single-centre case series of 49 infants explored early SWS care. Ninety-two per cent of children developed seizures aged 0 to 3 years; 55% of cases were before diagnostic magnetic resonance imaging (MRI) or tertiary referral. Delay in SWS diagnosis affected 31% of infants because of a lack of gadolinium enhancement for initial MRI. First seizures were frequently prolonged, with phenytoin administration necessary in 46%. Presymptomatic antiseizure medication prophylaxis (n = 8/49) decreased seizure burden. No patients on antiseizure medication prophylaxis suffered status epilepticus for longer than 30 minutes, and half of them (n = 4) had not developed seizures at last follow-up (aged 2-10 years). RESULTS: A parental survey enabled further service evaluation. Eighty-three per cent of parents considered local clinicians' understanding of SWS inadequate: 61% felt insufficiently informed about SWS and 81% received no epilepsy education before seizures. INTERPRETATION: To overcome the identified shortfalls, guidelines towards improving and standardizing SWS management are proposed.

GNAQ/GNA11 Mosaicism Is Associated with Abnormal Serum Calcium Indices and Microvascular Neurocalcification.

Mosaic mutations in genes GNAQ or GNA11 lead to a spectrum of diseases including Sturge-Weber syndrome and phakomatosis pigmentovascularis with dermal melanocytosis. The pathognomonic finding of localized "tramlining" on plain skull radiography, representing medium-sized neurovascular calcification and associated with postnatal neurological deterioration, led us to study calcium metabolism in a cohort of 42 children. In this study, we find that 74% of patients had at least one abnormal measurement of calcium metabolism, the commonest being moderately low serum ionized calcium (41%) or high parathyroid hormone (17%). Lower levels of ionized calcium even within the normal range were significantly associated with seizures, and with specific antiepileptics despite normal vitamin D levels. Successive measurements documented substantial intrapersonal fluctuation in indices over time, and DEXA scans were normal in patients with hypocalcemia. Neurohistology from epilepsy surgery in five patients revealed not only intravascular, but perivascular and intraparenchymal mineral deposition and intraparenchymal microvascular disease in addition to previously reported findings. Neuroradiology review clearly demonstrated progressive calcium deposition in individuals over time. These findings and those of the adjoining paper suggest that calcium deposition in the brain of patients with GNAQ/GNA11 mosaicism may not be a nonspecific sign of damage as was previously thought, but may instead reflect the central postnatal pathological process in this disease spectrum.

Hypothalamic hamartoma: epilepsy and neurodevelopmental profiles in a clinical cohort

Objective: We aimed to determine the prevalence of epilepsy and neurodevelopmental disorders, including autism spectrum disorder, in children and adolescents with hypothalamic hamartoma (HH). We also sought to explore the relationship between these neurodevelopmental comorbidities and epilepsy and to establish the predictive value of structural characteristics of the hamartoma itself. Methods: We retrospectively studied a cohort of 62 children with HH, with neuroimaging reviewed at Great Ormond Street Hospital (GOSH) between 2008 and 2018. Clinical records were reviewed, cognitive and language data analysed, and MRI scans studied. Results: We confirmed a high burden of epilepsy (56%), autism (19%) and other neurodevelopmental disorders. Although rates of some neurodevelopmental disorders were significantly higher in those with epilepsy, autistic features and/or early developmental concerns often predated the onset of seizures, in particular generalized seizures, or occurred independently of seizures. We found a significant correlation between certain structural characteristics of the hamartoma itself and both epilepsy and certain neurodevelopmental comorbidities. Significance: These findings suggest that although seizure burden clearly contributes to the cognitive and behavioural phenotypes seen, the hamartoma itself, and particular characteristics of it, are likely to be primary determinants of both the epilepsy and neurodevelopmental profiles. It is also probable that the underlying aetiology, likely genetic, directly contributes to the clinical profile, with epilepsy, neurodevelopmental impairment and the hamartoma itself representing markers of this aetiology. We propose that atypical neurodevelopmental profiles in HH could best be conceptualized as a developmental and epileptic encephalopathy. These findings have implications for counselling, monitoring and treatment.

The prevalence and profile of autism in Sturge-Weber syndrome.

A systematic retrospective case note review was undertaken to investigate autism diagnostic factors in 124 individuals with Sturge-Weber syndrome (SWS). Social Responsiveness Scale questionnaires were then analysed to explore the severity and profile of autism characteristics in 70 participants. Thirty-two to forty percent of participants had a clinical diagnosis of autism and half of those without a diagnosis showed significant social communication difficulties. Children had a relative strength in social awareness and social motivation, which are typically much reduced in people with autism. This finding may explain why, to date, the diagnosis has often been overlooked in this population. The research therefore suggests that children with Sturge-Weber should be screened to identify social communications difficulties and provided with timely support.

Neurological presentations and cognitive outcome in Sturge-Weber syndrome.

INTRODUCTION: This study of children with Sturge-Weber syndrome (SWS) profiled neurological presentations; compared patients with (+) and without (-) port-wine stain (PWS); and determined risk factors for intellectual and language impairments. METHODS: A retrospective case note review was conducted at a national centre. RESULTS: This cohort (n = 140, male 72, median follow up 114 months) showed sex parity. Intellectual disability ("ID": IQ ≤ 70) affected half (66), being severe (IQ ≤ 40) in two-fifths (27) with ID. Language disorder (core score≤70) affected half (57). Neurological presentations were: status epilepticus 57% (80), hemiplegia 58% (81), headaches 36% (50) and acutely acquired neurological deficits lasting over 24 h 40% (56). One-seventh (20) were PWS(-). This group had: fewer lobes with angioma (p < 0.0001); and less frequent ID (p = 0.002) or language disorder (p = 0.013). Seizure frequency and status epilepticus prevalence did not differ from PWS(+). ID and language disorder were associated with: more lobes with angioma; earlier seizure onset; more frequent status epilepticus and seizure clusters. On multivariable analysis recurrent status epilepticus (p = 0.037) and multi-lobe involvement (p = 0.002) increased the risk of severe intellectual disability. Active epilepsy was associated with language disorder (p = 0.030). CONCLUSIONS: This is the largest reported series documenting detailed developmental profiles of children with SWS, including ID and ASD. PWS(+) shows high rates of ID and language disorder. PWS(-) SWS has a more favourable outcome. Cognitive outcome is contingent on number of affected lobes and bilateral involvement. Epilepsy exerts an additional deleterious effect on language and cognition. A high percentage of children have a history of status epilepticus, with evidence that this impacts language and cognitive outcomes. Acutely acquired neurological deficits did not penalise either. Regular structured clinical and developmental assessment permit greater identification of neurological and neurodevelopmental impairments in SWS, and appropriate support.