Clinical phenotype and mutation characteristics of germline PIGA gene mutations / 中华实用儿科临床杂志

ABSTRACT

Objective:To analyze the clinical phenotype and genetic characteristics of children with germline PIGA gene mutations. Methods:The clinical presentations, blood biochemistry, electroencephalogram (EEG), brain magnetic resonance imaging (MRI) and genetic test results of 10 children diagnosed at the Department of Pediatrics of Peking University First Hospital between January 2014 and June 2020 were analyzed.Results:All these 10 children were male, with seizures and severe developmental delay.Five out of eight cases showed hypotonia.Four out of nine cases had facial deformity or multiple organ abnormalities.The onset age of seizures ranged from one month and 28 days to 10 months, with an average age of 4.8 months.There were various types of seizures, and all patients showed focal seizures.The seizures of 6 patients in these 10 cases could be induced by fever disease.Diffuse slow waves mixed focal or multifocal discharges of interictal EEG in 9 cases with PIGA-deficient.Brain MRI showed enlarged subarachnoid space in 44.4% (4/9 cases) of patients.Slight elevated serum alkaline phosphatase could be seen in 2 cases.Genetic analysis confirmed that a total of 8 different mutation sites were found, 7 of which were unreported.In this group, 4 cases were diagnosed with multiple congenital anomalies -hypotonia -seizures syndrome 2 (MCAHS2), 5 cases were diagnosed with developmental delay and epilepsy without deformity, and one case was not classified, respectively. Conclusions:Focal seizure was common in these patients with PIGA mutations, and often induced by fever disease.Interictal EEG was characterized by diffuse slow waves mixed focal or multifocal discharges.Enlarged subarachnoid space was the most common brain MRI abnormality in these patients.The phenotype of patients only partially conformed to typical MCAHS2 manifestations, and most of them had no deformity.