In 5 prospectively diagnosed patients with relapsing post–herpes simplex encephalitis (HSE), N‐methyl‐D‐aspartate receptor (NMDAR) antibodies were identified. Antibody synthesis started 1 to 4 weeks ...after HSE, preceding the neurological relapse. Three of 5 patients improved postimmunotherapy, 1 spontaneously, and 1 has started to improve. Two additional patients with NMDAR antibodies, 9 with unknown neuronal surface antibodies, and 1 with NMDAR and unknown antibodies, were identified during retrospective assessment of 34 HSE patients; the frequency of autoantibodies increased over time (serum, p = 0.004; cerebrospinal fluid, p = 0.04). The 3 retrospectively identified NMDAR antibody–positive patients also had evidence of relapsing post‐HSE. Overall, these findings indicate that HSE triggers NMDAR antibodies and potentially other brain autoimmunity. Ann Neurol 2014;75:317–323
Highlights • We confirm the existence of a new epilepsy syndrome after HHV6-PALE in children. • It may present with epileptic encephalopathy featuring epileptic spasms. • Bilateral temporal lobe ...involvement may not be evident on MRI in the short-term. • Clinical manifestations are refractory to rituximab and other immunomodulating agents. • Further evidence arguing against an immune-mediated basis is provided.
Acute bilateral striatal necrosis (ABSN) is a clinicoradiological syndrome with different causes: genetic (mostly, inborn errors of metabolism) and acquired. Among these, parainfectious forms are ...especially relevant, since they may be confused with genetic forms, but carry a better prognosis and may benefit from immunomodulation.
ABSN presents with any combination of movement disorders, altered state of awareness and seizures. The latter warrant an EEG, likely to be performed before imaging can confirm the syndromic diagnosis.
To describe the electroclinical findings of pediatric patients with confirmed parainfectious ABSN attending our hospital between 01/2015 and 12/2015.
Retrospective review of clinical records of patients fulfilling the following:
–Age at onset ⩽16 years.–Onset of movement disorders, altered level of awareness or seizures within 3 weeks of a febrile episode.–Acute bilateral neostriatal lesions (enlargement and T2/Flair hyperintensity on MR or hypodensity on CT of caudate and/or putamen bilaterally).–Evidence of recent/ongoing infection in biological samples (Direct: Positive culture/PCR; Indirect: Seroconversion/Raising antibody titres).
–Progressive course after 6 weeks–Evidence of a metabolic disorder (Positive genetic testing for pathogenic mutations or confirmed altered enzyme activity/altered biochemical markers in biological samples).–Alternative cause.
We found 2 cases: 1. 11 year old boy presenting with focal seizures and parkinsonism, 48 h after a febrile episode. MR showed symmetric striatal inflammation and patchy cortical edema, predominantly frontal. CSF analysis showed mononuclear pleocytosis and increased protein. A tracheal aspirate disclosed M. pneumoniae infection. Metabolic screening was negative. Control of seizures was difficult, requiring combined treatment with LEV, LCM, VPA, Antibiotics, IVIG and glucocorticoids. Serial EEGs showed diffuse background slowing and focal asymmetric fronto-temporal slowing (right worse). He was discharged asymptomatic after 13 days, on LEV and LCM, which were stopped over the following 5 months. MR and EEG were normal 3 months after onset. 2: 2 year old girl presenting with parkinsonism, dystonia and bulbar symptoms 7 days after a febrile episode. MR showed symmetric striatal inflammation. CSF analysis was normal, but HHV6 replication was shown in plasma and CSF. EEG was normal. Metabolic screening showed raised urinary 3-OH-glutaric acid, not confirmed on repeated tests. She was treated with foscarnet, IVIG and glucocorticoids and was discharged after 43 days, with mild symptoms. She was asymptomatic at 8 months follow-up. Control MR showed atrophy and cavitation of posterior putamina.
EEG allows objective assessment and monitoring of brain function in parainfectious ABSN, when it presents with seizures and/or altered level of awareness. Focal abnormalities may correlate with damage beyond the striatum and into the cortex.
Neonatal hypoglycemia is a relatively common event with a variable clinical presentation, ranging from asymptomatic forms to refractory status epilepticus. It may present as a primary problem or ...appear in the context of other conditions, such as prematurity or severe systemic disorders (sepsis, hypoxic ischemic encephalopathy, ...), making it difficult to separate its effects on the CNS from those due to the underlying disorder. Aim: To describe the EEG features in term-newborns with primary hypoglycemia admitted to our neonatal unit between 10/2016 and 10/2017.
Retrospective review of clinical records of patients fulfilling the following: Inclusion criteria
– Term newborns (Gestational age ⩾37 weeks).
– Hypoglycemia (plasma glucose ⩽40 mg/dL or ⩽47 mg/dL if symptomatic: CNS dysfunction; dysautonomia).
Exclusion criteria
– Any antecedent disorder that may explain CNS dysfunction (Primary: e.g. genetic epileptic encephalopathy; Secondary: e.g. cardiorespiratory arrest).
We identified 3 patients: 1. Female, presenting with irritability and tremor 48 h. after birth, with plasma glucose of 18 mg/dL, treated with oral glucose with good response. She presented recurrent asymptomatic hypoglycemia, with disproportionately high levels of insulin and C-peptide, and was treated with Cortisone and Diazoxide. Genetic tests confirmed congenital hyperinsulinism (ABCC8-mutation). MR and EEG were normal. At follow-up, 7 months old, she had a normal psychomotor development. 2. Male, presenting with hypoactivity, diaphoresis, and apnea 12 h. after birth, with plasma glucose of 15 mg/dL, metabolic acidosis and high lactate, improving rapidly on i.v. Glucose. His mother had insulin-treated gestational diabetes. He developed focal seizures evolving into status epilepticus, requiring treatment with PB, LEV, MDZ and Lidocaine to achieve control (48 h. after onset). MR showed extensive bilateral cortico-subcortical lesions, predominantly parieto-occipital. Initial EEG showed a discontinuous pattern and 8 focal temporal seizures. Control EEG showed persistent discontinuous pattern (silent periods up to 2 min) and absent cortical reactivity. He died aged 4 days. 3. Male, presenting with hypoactivity with plasma glucose of 16 mg/dL, rapidly improving with i.v. Glucose. He developed focal motor seizures evolving into status epilepticus, requiring PB, LEV and MDZ to achieve control (clinically after 24 h, but seizures persisted on CFM 12 h longer). MR showed bilateral cortico-subcortical lesions, predominantly parieto-occipital. Initial EEG showed normal background with left centro-temporal interictal epileptiform activity. Control EEG showed focal slowing over the same regions. He was discharged on LEV 23 days after onset, with axial hypertonia and brisk reflexes.
Neonatal hypoglycemia may present with refractory seizures, which can aggravate CNS damage and impair outcome. EEG monitoring is necessary to identify subclinical seizures and correlates with prognosis.
Mutations on SYNGAP1, which encodes a main protein in the postsynaptic regulating NMDA cascade responsible of the formation and maturation of dendritic spines, were described in patients with ...intellectual disability, autism spectrum disorder and epilepsy. Since this entity has its own characteristic features, it could be considered as a syndromic type of developmental and epileptic encephalopathy (DEE). Our aim is to review the electroencephalographic features and compare them with the evolution of a 6-year-old girl with a confirmed frameshift mutation.
A PubMED research was done with the keywords “SYNGAP1”, ”encephalopathy”, “epilepsy” and “EEG or electroencephalography”, of recent case or case series reports that include well described EEG characteristics and compare them with the video-EEG tests performed in our patient.
The first video-EEG at 5 years old, showed a diffuse slowing background with frontal delta waves and generalized polyspike-wave discharges, that correlated with eyelid myoclonia, neck retropulsion with or without limb myoclonus or fall. Follow-up EEGs also showed multifocal discharges and bioccipital photoparoxysmal response.
This case provides a complete clinical and video-EEG evidence of a new type of seizures that are particularly characteristic of SYNGAP1 DEE, as well as the dynamical evolution within the years of the patient’s own background, ictal and interictal patterns.
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