Clinical Review of Juvenile Huntington's Disease.

 Juvenile Huntington's disease (JHD) is rare. In the first decade of life speech difficulties, rigidity, and dystonia are common clinical motor symptoms, whereas onset in the second decade motor symptoms may sometimes resemble adult-onset Huntington's disease (AOHD). Cognitive decline is mostly detected by declining school performances. Behavioral symptoms in general do not differ from AOHD but may be confused with autism spectrum disorder or attention deficit hyperactivity disorder and lead to misdiagnosis and/or diagnostic delay. JHD specific features are epilepsy, ataxia, spasticity, pain, itching, and possibly liver steatosis. Disease progression of JHD is faster compared to AOHD and the disease duration is shorter, particularly in case of higher CAG repeat lengths. The diagnosis is based on clinical judgement in combination with a positive family history and/or DNA analysis after careful consideration. Repeat length in JHD is usually > 55 and caused by anticipation, usually via paternal transmission. There are no pharmacological and multidisciplinary guidelines for JHD treatment. Future perspectives for earlier diagnosis are better diagnostic markers such as qualitative MRI and neurofilament light in serum.

Single-Center Incidence and Patterns of Stroke in Early Renal Anhydramnios After Serial Amnioinfusions.

The Renal Anhydramnios Fetal Therapy (RAFT) trial is a study of serial amnioinfusions to prevent lethal neonatal pulmonary hypoplasia from early renal anhydramnios. Infant neurologic outcomes were not originally evaluated. We describe the high incidence of stroke observed among infants in the treatment arm of the trial at our center.

Pearls & Oy-sters: Epilepsy Is a Key Feature of Pediatric-Onset Huntington Disease.

Pediatric-onset Huntington disease (PoHD) presents differently from adult-onset disease. Children typically exhibit regression in school performance, psychiatric features such as inattention, and oral motor dysfunction. Unlike adult-onset HD, in which seizures occur at approximately the rate of the general public, at least half of children with HD develop epilepsy, and seizures can be a presenting feature of PoHD. Here we present the case of a 10-year-old boy with a history of language delay, motor regression, oral motor dysfunction, and tremor who presented with a first lifetime seizure. Given a family history of Huntington disease in his father, PoHD was considered, and a pathogenic allele with 88 repeats was confirmed in the child. As symptoms progressed, history alone could not differentiate abnormal movements from seizures. Continuous video electroencephalography helped to demonstrate epileptic myoclonic jerks and guide treatment.

Fatal SARS-CoV-2 Inflammatory Syndrome and Myocarditis in an Adolescent: A Case Report.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), an entity in children initially characterized by milder case presentations and better prognoses as compared with adults. Recent reports, however, raise concern for a new hyperinflammatory entity in a subset of pediatric COVID-19 patients. METHODS: We report a fatal case of confirmed COVID-19 with hyperinflammatory features concerning for both multi-inflammatory syndrome in children (MIS-C) and primary COVID-19. RESULTS: This case highlights the ambiguity in distinguishing between these two entities in a subset of pediatric patients with COVID-19-related disease and the rapid decompensation these patients may experience. CONCLUSIONS: Appropriate clinical suspicion is necessary for both acute disease and MIS-C. SARS-CoV-2 serologic tests obtained early in the diagnostic process may help to narrow down the differential but does not distinguish between acute COVID-19 and MIS-C. Better understanding of the hyperinflammatory changes associated with MIS-C and acute COVID-19 in children will help delineate the roles for therapies, particularly if there is a hybrid phenotype occurring in adolescents.

Lead Exposure in Newly Resettled Pediatric Refugees in Syracuse, NY.

Lead is a major environmental toxin that presents numerous health consequences for children. Refugee children are at a risk of lead poisoning post-resettlement due to urban housing and environmental inequalities stemming from lack of funding, legislation, and advocacy. This article addresses lead exposure upon arrival and post-resettlement in 705 refugee children (age 0-16 years) attending a university clinic in Syracuse, NY, a city with a large refugee population. 17% of the newly arrived children had elevated blood lead levels (BLLs) (≥ 5 µg/dL); 10% had elevated BLL upon follow-up; 8.3% of the children's follow-up elevated BLL were new exposures. 30% were found to have increased BLL at follow-up regardless of arrival status. An analysis of new exposures found a significant proportion of children would have been missed on routine screening that targets children < 2 years old. Primary prevention efforts are needed to prevent exposure and address risks to improve the health of all children locally, including newly resettled refugees.

Central and peripheral dysmyelination in a 3-year-old girl with ring chromosome 18.

Myelin basic protein (MBP) contributes to peripheral and central nervous system myelin. Developmental myelinopathies exist on a clinical spectrum, but MBP is not included on leukodystrophy or CMT gene panels. This ring chromosome 18 case presents serial MRI and EMG/NCS, shedding light on the early clinical course of the disorder.

The de novo autism spectrum disorder RELN R2290C mutation reduces Reelin secretion and increases protein disulfide isomerase expression.

Despite the recent identification of over 40 missense heterozygous Reelin gene (RELN) mutations in autism spectrum disorder (ASD), none of these has been functionally characterized. Reelin is an integral signaling ligand for proper brain development and post-natal synapse function - properties likely disrupted in ASD patients. We find that the R2290C mutation, which arose de novo in an affected ASD proband, and other analogous mutations in arginine-amino acid-arginine domains reduce protein secretion. Closer analysis of RELN R2290C heterozygous neurospheres reveals up-regulation of Protein Disulfide Isomerase A1, best known as an endoplasmic reticulum-chaperone protein, which has been linked to neuronal pathology. This effect is recapitulated in a heterozygous RELN mouse mutant that is characterized by defective Reelin secretion. These findings suggest that both a deficiency in Reelin signaling and pathologic impairment of Reelin secretion may contribute to ASD risk.

RELN Mutations in Autism Spectrum Disorder.

RELN encodes a large, secreted glycoprotein integral to proper neuronal positioning during development and regulation of synaptic function postnatally. Rare, homozygous, null mutations lead to lissencephaly with cerebellar hypoplasia (LCH), accompanied by developmental delay and epilepsy. Until recently, little was known about the frequency or consequences of heterozygous mutations. Several lines of evidence from multiple studies now implicate heterozygous mutations in RELN in autism spectrum disorders (ASD). RELN maps to the AUTS1 locus on 7q22, and at this time over 40 distinct mutations have been identified that would alter the protein sequence, four of which are de novo. The RELN mutations that are most clearly consequential are those that are predicted to inactivate the signaling function of the encoded protein and those that fall in a highly conserved RXR motif found at the core of the 16 Reelin subrepeats. Despite the growing evidence of RELN dysfunction in ASD, it appears that these mutations in isolation are insufficient and that secondary genetic or environmental factors are likely required for a diagnosis.