Analysis of clinical features of children with acute encephalopathy caused by ATP1A2 variants

DAI Li-fang; LI Hua; WANG Xu; ZHANG Ying; TIAN Xiao-juan; REN Shu-hong; XIONG Hui; DING Chang-hong

doi:10.19538/j.ek2025100610

Abstract：Objective To summarize the clinical manifestations,genetic features and treatments of children with acute encephalopathy caused by ATP1A2 gene variants,in order to improve the understanding of the disease.Methods The clinical manifestations,treatment and genetic variant spectrum of eight children with acute encephalopathy caused by ATP1A2 gene variants diagnosed in the Department of Neurology of Beijing Children's Hospital,Capital Medical University from 2015 to 2024 were retrospectively summarized and analyzed,and the child patients were followed up.Results There were four males and four females.The age at onset was from 5 months to 5 years 9 months.The causes included fever in eight patients,the intake of large amounts of food in two patients and mild head trauma in one patient.The onset symptoms were coma in five patients and lethargy in three patients(one patient with dysphoria).The time of symptoms reaching peak was from onset to over 4 days.GTCS occurred in eight patients,hemiplegia occurred in four patients,and aphasia occurred in five patients.None of the eight patients had headache.Disturbance of consciousness lasted from 40 hours to 9 days,and hemiplegia and aphasia lasted from 19 days to 6 months and from 8 days to 26 days,respectively.Previous episodes of encephalopathy ranged from 0 to 6 times.Two patients respectively developed seizure without fever in 1 year 6 months old and 5 years 8 months old.Six patients had recurrent fever and convulsions between 5 months and 2 years 5 months old.Alternating hemiplegia occurred in 2 patients aged from 5 to 10 years old and lasted from 30 minutes to 3 days.Four patients had mild mental retardation.Single or bilateral cerebral cortical cytotoxic edema was shown in cerebral MRI in five patients during acute stage,mild cerebral atrophic changes were shown at recovery stage,and one of them had smaller right cerebral hemisphere,delayed myelination,and a malformed and deepened cerebral fissure in left occipital lobe.Generalized slow wave was observed in EEG in five patients during acute stage;periodic slow wave was observed in two patients;left frontal spike wave,spike slow wave and left frontal-origin subclinical seizures were detected in one patient during recovery stage.Six ATP1A2 gene variants were found in the 8 cases,including four inherited variants and four de novo variants.One novel variant c.2540T＞A(p.p.I847N),and two hot spot variants c.2563G＞A(p.G855R)and c.2143G＞A(p.G715R)were found.Conclusion Acute encephalopathy in children caused by ATP1A2 gene variants is likely to occur under stress of fever,head trauma,and intake of large amounts of food.The initial symptom is often coma,which is often combined with GTCS,hemiplegia,and aphasia.The course of the disease is reversible and can recur.Generally,headache does not occur in the acute stage,and it is easy to be misdiagnosed as viral encephalitis and cerebral infarction.Avoiding triggering factors and giving symptomatic treatment are the main treatment methods.