Giovanni Baranello1, Enrico Alfei2, Diego Martinelli3, Manuela Rizzetto4, Fabiana Cazzaniga2, Carlo Dionisi-Vici3, Cinzia Gellera4, Barbara Castellotti4. 1. Developmental Neurology Unit, Pediatric Neuroscience Department, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Milan, Italy. Electronic address: giovanni.baranello@istituto-besta.it. 2. Developmental Neurology Unit, Pediatric Neuroscience Department, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Milan, Italy. 3. Division of Metabolism, Department of Pediatrics, "Bambino Gesù" Children's Hospital, IRCCS, Rome, Italy. 4. Unit of Genetics of Neurodegenerative and Metabolic Diseases, Department of Diagnostic and Applied Techonology, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Milan, Italy.
Abstract
BACKGROUND: Hyperargininemia due to mutations in ARG1 gene is an autosomal recessive inborn error of metabolism caused by a defect in the final step of the urea cycle. Common clinical presentation is a variable association of progressive spastic paraparesis, epilepsy, and cognitive deficits. METHODS: We describe the clinical history of an Italian child presenting progressive spastic paraparesis, carrying a new homozygous missense mutation in the ARG1 gene. A detailed clinical, biochemical, and neurophysiological follow-up after 7 months of sodium benzoate therapy is reported. RESULTS: Laboratory findings, gait abnormalities, spastic paraparesis, and electroencephalographic and neurophysiological abnormalities remained quite stable over the follow-up. Conversely, a mild cognitive deterioration has been detected by means of the neuropsychologic assessment. CONCLUSIONS: Further longitudinal studies by means of longer follow-up and using clinical, biochemical, radiological, and neurophysiological assessments are needed in such patients to describe natural history and monitor the effects of treatments.
BACKGROUND:Hyperargininemia due to mutations in ARG1 gene is an autosomal recessive inborn error of metabolism caused by a defect in the final step of the urea cycle. Common clinical presentation is a variable association of progressive spastic paraparesis, epilepsy, and cognitive deficits. METHODS: We describe the clinical history of an Italian child presenting progressive spastic paraparesis, carrying a new homozygous missense mutation in the ARG1 gene. A detailed clinical, biochemical, and neurophysiological follow-up after 7 months of sodium benzoate therapy is reported. RESULTS: Laboratory findings, gait abnormalities, spastic paraparesis, and electroencephalographic and neurophysiological abnormalities remained quite stable over the follow-up. Conversely, a mild cognitive deterioration has been detected by means of the neuropsychologic assessment. CONCLUSIONS: Further longitudinal studies by means of longer follow-up and using clinical, biochemical, radiological, and neurophysiological assessments are needed in such patients to describe natural history and monitor the effects of treatments.