ABSTRACT
Objective:To analyze the clinical phenotype and genotype characteristics of infantile spasm (IS) associated with UBA5 gene mutation. Methods:Four cases of IS caused by UBA5 gene variation diagnosed at the Department of Pediatrics, Peking University First Hospital from March 2017 to June 2019 were retrospectively analyzed.The clinical manifestations, electroencephalogram (EEG), brain magnetic resonance imaging (MRI), treatment, and follow-up results were summarized. Results:In this study, 4 cases (3 males and 1 female) were clinically diagnosed with IS and carried complex heterozygous variation of UBA5 gene.Genetic analysis confirmed that a total of 6 different mutation sites were found, five of which were unreported.All the 4 cases presented with epileptic spasms at the age of 1 d to 8 months after birth, and 2 cases had focal seizures during the course of disease.The EEG of 4 cases showed hypsarrhythmia and cluster or isolated epileptic spasms were detected.Of the 3 patients who had brain MRI results, 2 cases showed nonspecific abnormalities and 1 case was normal.All the 4 patients had developmental delayed before seizure onset, and regressed to varying degrees and made slow progress after onset.One case had microcephaly, and 3 cases had hypertonia.At the last follow-up, the age of the 4 patients ranged from 7 months to 6 years and 4 months.All 4 patients were treated with multiple antiepileptic drugs, but none of them were under control. Conclusions:Children with IS associated with UBA5 gene variation have an early onset age, often accompanied by developmental delayed, microcephaly, dystonia, and refractory seizures.