Homozygous UBA5 Variant Leads to Hypomyelination with Thalamic Involvement and Axonal Neuropathy

The enzyme ubiquitin-like modifier activating enzyme 5 (UBA5) plays an important role in activating ubiquitin-fold modifier 1 (UFM1) and its associated cascade. UFM1 is widely expressed and known to facilitate the post-translational modification of proteins. Variants in UBA5 and UFM1 are involved in neurodevelopmental disorders with early-onset epileptic encephalopathy as a frequently seen disease manifestation. Using whole exome sequencing, we detected a homozygous UBA5 variant (c.895C > T p. [Pro299Ser]) in a patient with severe global developmental delay and epilepsy, the latter from the age of 4 years. Magnetic resonance imaging showed hypomyelination with atrophy and T2 hyperintensity of the thalamus. Histology of the sural nerve showed axonal neuropathy with decreased myelin. Functional analyses confirmed the effect of the Pro299Ser variant on UBA5 protein function, showing 58% residual protein activity. Our findings indicate that the epilepsy currently associated with UBA5 variants may present later in life than previously thought, and that radiological signs include hypomyelination and thalamic involvement. The data also reinforce recently reported associations between UBA5 variants and peripheral neuropathy

Neonatal seizures:Aetiology by means of a standardized work-up

Neonatal seizures are an alarming symptom and are frequent in neonates. It is important to find the cause of neonatal seizures to start a specific treatment and to give a meaningful prognosis. The aim of this study is to investigate the incidence of different aetiologies of neonatal seizures in our hospital by a specific work-up. Methods: All full-term born neonates from January 2002 till September 2009 with neonatal seizures, admitted to our neonatal intensive care unit were included (n = 221). Aetiology was investigated by means of a standardized aetiologic work-up. Results: The frequencies of aetiologies of neonatal seizures were: hypoxic-ischemic encephalopathy (HIE) (n = 119; 53.9%), metabolic or electrolyte disorders (n = 24; 10.9%), intracranial hemorrhage (n = 20; 9.0%), ischemic infarction (n = 16; 7.2%), intracranial infections (n = 14; 6.3%), congenital malformations of the central nervous system (n = 7; 3.2%), inborn errors of metabolism (n = 5; 2.3%), epileptic syndromes (n = 1; 0.5%), HIE + hypoglycemia (n = 4; 1.8%), HIE + intracranial hemorrhage (n = 3; 1.4%), HIE + ischemic infarction (n = 1; 0.5%), ischemic infarction + intracranial hemorrhage (n = 1; 0.5%), idiopathic (n = 4, 1.8%), intoxications (n = 1; 0.5%) and unknown (n = 1; 0.5%). Conclusion: Our work-up is a practical tool to find the aetiology of neonatal seizures. (C) 2014 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved

Favorable Outcome in a Newborn With Molybdenum Cofactor Type A Deficiency Treated With cPMP

Molybdenum cofactor deficiency (MoCD) is a lethal autosomal recessive inborn error of metabolism with devastating neurologic manifestations. Currently, experimental treatment with cyclic pyranopterin monophosphate (cPMP) is available for patients with MoCD type A caused by a mutation in the MOCS-1 gene. Here we report the first case of an infant, prenatally diagnosed with MoCD type A, whom we started on treatment with cPMP 4 hours after birth. The most reliable method to evaluate neurologic functioning in early infancy is to assess the quality of general movements (GMs) and fidgety movements (FMs). After a brief period of seizures and cramped-synchronized GMs on the first day, our patient showed no further clinical signs of neurologic deterioration. Her quality of GMs was normal by the end of the first week. Rapid improvement of GM quality together with normal FMs at 3 months is highly predictive of normal neurologic outcome. We demonstrated that a daily cPMP dose of even 80 mu g/kg in the first 12 days reduced the effects of neuro-degenerative damage even when seizures and cramped-synchronized GMs were already present. We strongly recommend starting cPMP treatment as soon as possible after birth in infants diagnosed with MoCD type A. Pediatrics 2012; 130: e1005-e101

Clinical and biochemical spectrum of D-bifunctional protein deficiency

OBJECTIVE: D-bifunctional protein deficiency is an autosomal recessive inborn error of peroxisomal fatty acid oxidation. Although case reports and small series of patients have been published, these do not give a complete and balanced picture of the clinical and biochemical spectrum associated with this disorder. METHODS: To improve early recognition, diagnosis, prognosis, and management of this disorder and to provide markers for life expectancy, we performed extensive biochemical studies in a large cohort of D-bifunctional protein-deficient patients and sent out questionnaires about clinical signs and symptoms to the responsible physicians. RESULTS: Virtually all children presented with neonatal hypotonia and seizures and died within the first 2 years of life without achieving any developmental milestones. However, within our cohort, 12 patients survived beyond the age of 2 years, and detailed information on 5 patients with prolonged survival (> or =7.5 years) is provided. INTERPRETATION: Biochemical analyses showed that there is a clear correlation between several biochemical parameters and survival of the patient, with C26:0 beta-oxidation activity in cultured skin fibroblasts being the best predictive marker for life expectancy. Remarkably, three patients were identified without biochemical abnormalities in plasma, stressing that D-bifunctional protein deficiency cannot be excluded when all peroxisomal parameters in plasma are norma