Objective:To summarize the clinical and genetic characteristics of mental retardation disorder (MRD) with TRIO gene variant in children.Methods:Case series study. The data of 9 children with TRIO gene variants were collected retrospectively from August 2019 to March 2024 in Department of Neurology, Beijing Children′s Hospital, Capital Medical University and Department of Pediatrics, the Third Affiliated Hospital of Zhengzhou University. The data included gender, age, intellectual and motor development, appearance, seizures, neuroimaging and genetic results. The clinical features and genotype-phenotype correlations were summarized.Results:Of the 9 children, 6 boys and 3 girls, 4 MRD63 children presented with moderate to severe developmental delays accompanied by macrocephaly; 5 MRD44 children had mild to moderate developmental delays with microcephaly. A total of 5 children had dysmorphic facial features (flat occiput, thick eyebrows, unibrow, large ears, short fingers, pale skin, yellow hair, and strabismus), 2 children experienced seizures (1 child with myoclonic seizure and 1 with absence seizure), 4 children had feeding difficulties, 1 child had congenital cataracts, 1 child had congenital heart disease, 1 child had recurrent infections, and 1 child had tiger-striped changes in the fundus examination. TRIO gene variants carried by the 9 children were all de novo, involving 8 variant sites, including 7 missense variants and 1 frameshift variant, c.3232C>T/p.R1078W (2 cases), c.3920A>G/p.Y1307C, c.4112A>T/p.H1371L, c.4283G>T/p.R1428L, c.4394A>G/p.N1465S, c.6041T>C/p.I2014T, c.6821G>A/p.R2274H, c.7027delC/p.Q2343Sfs*70. Among them, 2 sites are located in the Spectrin domain, 4 sites are in the GEFD1 domain, 2 sites are in the GEFD2 domain, and 1 site (frameshift variant) is in the PH2-SH3 domain. The individual with frameshift variant exhibit absence seizures, mild developmental delay, and the mildest phenotype. The child with myoclonic seizures was treated with valproic acid and levetiracetam for seizure control, while the child with absence epilepsy was treated with valproic acid and lamotrigine for seizure control. All 9 children underwent regular rehabilitation exercises, making slow progress.Conclusions:TRIO gene related MRD is characterized by varying degrees of developmental delay, and often accompanied by macrocephaly or microcephaly, dysmorphic facial features, and with or without seizures. The main variant types are missense variants, which are mostly concentrated in the Spectran domain and GEFD domain. p. R1078W may be a relative hotspot variant. The phenotype caused by the frameshift variant is relatively milder.

Objective:To investigate the clinical characteristics, laboratory characteristics and genetic diagnosis of aromatic L-amino acid decarboxylase deficiency (AADCD), and to improve the understanding of this disease.Methods:Four children diagnosed with AADCD from the Department of Neurology, Beijing Children′s Hospital Affiliated to Capital Medical University from August 2016 to June 2020 were collected, and their clinical manifestations, laboratory and imaging data, and genetic test results were retrospectively analyzed.Results:All the 4 cases were diagnosed in early infancy, with the first symptom of feeding difficulties. They developed paroxysmal dyspraxia accompanied by eye movement crisis, movement regression, hypotonia, growth retardation, sleep disorders and autonomic nervous symptoms such as ptosis, excessive sweating and nasal congestion at the age of 2-4 months, respectively. The 4 children were siblings from 2 families with healthy parents. The dihydroxyphenylalanine decarboxylase ( DDC) gene mutations in cases 1 and 2 were derived from the maternal missense mutation c.1040G>A(P.RG347gln), and from the paternal deletion of exons 11 and 12, respectively. The DDC gene mutation in case 3 was derived from the maternal mutation c.419G>A(p.G140E) and the paternal mutation c.1375C>T(p.H459Y), respectively. Case 4 did not undergo genetic testing. Blood amino acid and acylcarnitine profiles and urine organic acid analyses were performed in 3 cases, and no specific abnormalities were found. In case 3, the results of 3-O-methyldopa (3-OMD) screening by blood dry filter paper increased significantly. Cerebrospinal fluid neurotransmitter detection results showed that the concentrations of 3-methoxy-4-hydroxyphenyldiol, vanillic acid and 5-hydroxyindoleacetic acid were significantly decreased, while the levels of 5-hydroxytryptophan and 3-OMD were increased in case 3. Blood aromatic L-amino acid decarboxylase (AADC) activity decreased significantly in case 3. Cranial magnetic resonance imaging (MRI) and electroencephalogram (EEG) examinations were performed in cases 1, 3, and 4, among which the cranial MRI in case 1 was normal, while the cranial MRI in cases 3 and 4 suggested that myelination was slightly backward. The EEG was normal in all the 3 cases. Cases 1 and 2 died of pneumonia and respiratory failure at the age of 1 year and 10 months. Case 3 was given clonazepam, benxel hydrochloride tablets and vitamin B6 tablets orally after diagnosis at the age of 4 months, and then treated with selegiline hydrochloride tablets and pramexol hydrochloride tablets. At the follow-up of 1 year and 6 months, the frequency of eye movement crisis and movement disorder was reduced, sleep was improved and autonomic nervous symptoms were alleviated, but there was no improvement in developmental delay. Case 4 was diagnosed with cerebral palsy and epilepsy, but failed various antiepileptic drugs and rehabilitation training, and died at the age of 10 due to heart failure and kidney failure. Conclusions:The clinical manifestations of AADCD are complicated and the misdiagnosis rate is high. Infants with early-onset hypotonia, developmental retardation, eye movement crisis, and movement disorders should be screened with dry filter paper as soon as possible for 3-OMD level, and suspicious cases should be diagnosed by cerebrospinal fluid neurotransmitter detection, plasma AADC activity determination, and gene examination. Early diagnosis of AADCD in children and gene mutation carriers can guide treatment and provide genetic counseling to reduce the incidence of the offspring.

Objective:To summarize the clinical characteristics of children with dystonia 28 (DYT28) caused by KMT2B gene variations so as to improve clinicians′ understanding of the disease. Methods:The clinical manifestations, treatment and gene variation data of 11 children with DYT28 caused by KMT2B gene variations were retrospectively collected and analyzed.The subjects were recruited from the Department of Neurology, Beijing Children′s Hospital, Capital Medical University from March 2018 to January 2021.The patients were followed up. Results:There were 8 males and 3 females.The age at onset was ranging from 1 month to 6 years without inducement.Eight cases were gene-ralized dystonia and 3 cases were multifocal dystonia.The initial symptoms of 7 cases were unilateral or bilateral lower limbs tiptoeing.Four cases presented dysarthria, retching or swallowing difficulties at onset.As the disease progressed, all the cases had laryngeal dystonia, 10 cases had lower limbs dystonia, and 8 cases had upper limbs dystonia.Six cases were complicated with other dyskinesia symptoms.Ten cases had varying degrees of short stature, microcephalus, micrognathia, musculoskeletal abnormalities, intellectual disability, endocrinopathies and sleep difficulties.The brain magnetic resonance imaging showed abnormal in only 1 case.Eleven KMT2B gene pathogenic variants were found, including 8 frameshift variants, 1 in-frame variant and 2 missense variants.Four variants were novel.Eleven cases were followed up at the age of 1 year and 7 months to 17 years and 9 months.One case wasn′t given therapy.The dystonia in 3 cases was mildly improved after medication.Dysfunction of urination and defecation was disappeared in 1 case after medication.The symptom of 6 cases had no improvement after drug therapy.Among the above 6 cases, 5 drug refractory cases had deep brain stimulation, and their dystonia symptoms are all obviously improved; 2 cases had normal control of urination and defecation after deep brain stimulation.The motor scores in the Burke-Fahn-Marsden dystonia rating scale were improved by 55.8%-90.7%, and the disability scores were improved by 14.8%-69.6%. Conclusions:DYT28 caused by KMT2B gene variations is one of the most common and early-onset genetic dystonia in children.The dystonia symptom progresses from local parts to the whole body, prominently involving laryngeal muscles and lower limbs.Control of urination and defecation requires attention.Patients with mild dystonia symptoms can be effectively treated by drugs.However, patients with severe dystonia symptoms were drug refractory, and their dystonia symptoms can be effectively improved by deep brain stimulation.

Objective:To summarize the clinical characteristics and genetic features of tyrosine hydroxylase deficiency(THD) caused by TH gene variants for the improvement of the understanding of the disease. Methods:The clinical and genetic data of 33 children with THD caused by TH gene variants were diagnosed in the Department of Neurology of Beijing Children′s Hospital, Capital Medical University from May 2011 to January 2020 and their data were retrospectively collected and analyzed. Results:There were 19 females and 14 males.The age at onset was ranged from 0 to 6.3 years.13 patients developed diseases, accompanied with fever after infection, and 1 patient suffered from hypoxia, 19 patients suffered from no predisposing factors.There were 7 mild TH-deficient dopa-responsive dystonia cases, 16 severe TH-deficient infantile parkinsonism with motor delay cases and 10 very severe TH-deficient progressive infantile encephalopathy cases.Clinical symptoms were fluctuating, including 26 cases of diurnal fluctuation, 22 cases of infection aggravation, and 30 cases of fatigue aggravation.The initial symptoms included tiptoeing and numbness in the limbs(7 cases), motor development retardation or degression (26 cases), fremitus (8 cases), ptosis (2 cases), and status dystonicus (3 cases). Other clinical features had hypermyotonia (23 cases), hypomyotonia (27 cases), decreased movement (27 cases), decreased facial expression (24 cases), fremitus (18 cases), tiptoeing (20 cases), talipes equinovarus (7 cases), ptosis (8 cases), oculogyric crisis (10 cases), salivation (21 cases), dysphagia (12 cases), dysarthria (16 cases), dyspnea (3 cases), increased sleep (10 cases), decreased sleep (5 cases), irritable mood (15 cases), apathetic mood (2 cases), profuse sweating (8 cases), and status dystonicus (6 cases). A total of 6 patients′ right limbs were more severe, and 14 patients′ lower limbs were more severe.Eight patients had family history, and Levodopa treatment was effective for all patients.Ten patients suffered side effects, including dyskinesia and irritability.Four patients were lost follow-up, and 29 patients were followed up between 0.8 and 13.2 years old until Ja-nuary 2020.Totally, 22 patients almost had no such symptoms.Twenty-five TH gene pathogenic variants were discovered in 33 patients.There were 13 novel variants (c.1160T>C, c.1303T>C, c.887G>A, c.1084G>A, c.1097A>T, c.734G>T, c.907C>G, c.588G>T, c.992T>G, c.755G>A, c.184-6C>T, c.1510C>T, c.910G>A) and 2 patients had c. 910G>A variant.Meanwhile, there were 5 hot variants [c.698G>A(13 cases), c.457C>T(9 cases), c.739G>A(6 cases), c.1481C>T(4 cases), c.694C>T(3 cases)]. c.910G>A(2 cases) may be the foun-der variant of Chinese population. Conclusions:THD caused by TH gene variant mostly onsets from infant, with complex clinical features.Most of these patients were severe, and only a few were very severe and mild.Very severe and mild symptoms were easily misdiagnosed.Levodopa treatment was obviously effective.A possible founder variant of Chinese population (c.910G>A) was found.c.698G>A and c. 457C>T mutations mainly appeared in patients with severe and extremely severe THD, while c. 739G>A mainly appeared in patients with mild THD.

Objective:To summarize the clinical characteristics of SYNGAP1-related epilepsy in children.Methods:Data of 13 patients with SYNGAP1 gene variants diagnosed with epilepsy at Department of Neurology, Beijing Children's Hospital were collected retrospectively from March 2017 to October 2020 and the patients were followed up. The clinical features, electroencephalogram(EEG), brain imaging, gene results and treatment were summarized.Results:Twelve patients were followed up successfully among the 13 patients with SYNGAP1 variants. The last follow-up age was 5 years and 7 months (3 years and 1 month to 9 years).The onset age of seizures was 2 years (4 months to 3 years). Seizure types included eyelid myoclonia with or without absence (9 cases), myoclonic seizure (5 cases), atypical absence (4 cases), suspicious atonic seizures(4 cases),unclassified fall attack (6 cases), and the frequency of seizures varied from several times to more than 100 times per day. Four cases had the mimic phenotype of myoclonic astatic epilepsy. The seizures of 10 cases could be triggered by eating (5 cases), emotion (5 cases), fever (3 cases), voice (2 cases), fatigue (2 cases), etc. Electroencephalography (10 cases) showed interictal generalized or focal epileptiform discharges (9 cases), and atypical aphasia (4 cases), myoclonic seizure (2 cases) and eyelid myoclonic seizure (1 case) were monitored. Of the 12 cases, 9 were added with valproate, all of which were effective (the frequency of seizures reduced>50%). Five cases received combined levetiracetam, in 3 the treatments were effective. To last follow-up, 3 cases were seizure free from 6 months to 1 year and 1 month, but the remaining 7 cases still had seizures, one or several times per day. All 13 cases had developmental retardation (speech ability impaired mostly), 2 cases were severe, 10 cases were moderate, 1 case was mild. The SYNGAP1 gene variants of 13 patients were all de novo, including 12 variants. Among them, 4 were frameshift variants, 4 were nonsense variants, 2 were missense variants and 2 were splice site variants.Conclusions:Patients with SYNGAP1-related epilepsy have an early onset age and many seizure types. The main seizure type is eyelid myoclonia with or without absence, and other seizure types include myoclonic seizure, atypical absence, unclassified fall attack, etc. Valproate is effective in most patients, but seizures in some patients might be intractable. Most patients have developmental delay (mainly moderate and severe), speech ability impaired mostly.

Objective: To summarize the clinical and genetic characteristics of children with mitochondrial epilepsy. Methods: Clinical data of 62 children who were clinically and genetically diagnosed with mitochondrial epilepsy by the Department of Neurology, Beijing Children′s Hospital from October 2011 to December 2018 were analyzed retrospectively, and the control of epilepsy was followed up. T test or χ² test were used to analyze the related factors affecting the prognosis of epilepsy between the effective group and the ineffective group. Results: Of the 62 patients, 33 were male and 29 were female. The age of onset was 3.38 (0-12.00) years; for the type of seizures, 68% (42/62) of the patients had focal seizures, generalized or secondary generalized tonic-clonic seizures were seen in 32% (20/62), myoclonic seizures in 23% (14/62), spastic seizures in 7 cases, tonic seizures in 4 cases, absence seizure, atonic seizure and clonic seizure in 1 case each; 16 cases (26%) had status epilepticus, of whom 6 cases had epilepsia partialis continua; 52% (32/62) had 2 or more types of seizures. The clinical phenotypes were mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) in 29 cases, Leigh syndrome (LS) in 11 cases, combined oxidative phosphorylation deficiency in 6 cases, myoclonus epilepsy with ragged-red fibers in 5 cases, Alpers syndrome in 4 cases, pontocerebellar hypoplasia type 6 and mitochondrial DNA depletion syndrome 9 in 2 cases each, mitochondrial complex Ⅰ deficiency nuclear type 20, progressive cavitating leukoencephalopathy, and biotinidase deficiency in 1 case each. Of the 62 cases, 40 cases (65%) had mitochondrial DNA (mtDNA) variations, of which 26 cases had m.3243A>G variants, 6 cases had m.8344A>G variants, and 3 cases had m.8993T>G/C variants, m.3271T>C, m.3481G>A, m.3946G>A, m.13094T>C, m.14487T>C variant was in 1 case each; nuclear DNA (nDNA) variations were identified in 22 cases (35%), of which 7 cases carrying variations in mitochondrial ammonia acyl tRNA synthetase coding gene, mutations in POLG and the gene encoding complex Ⅰ were in 4 cases each, variations in SUCLG1 and SDHA genes were in 2 cases each, and variations in PDHA1, BTD and TRIT1 genes were in 1 case each. Forty-three patients were followed up, and the follow-up time was 20 (3-84) months. According to the follow-up results, the anti-epilepsy treatment was effective in 19 cases (44%) and ineffective in other 24 cases (56%). The onset age of the effective group was 3.42 (0-11.50) years and that of the ineffective group was 0.92 (0-9.50) years. The onset duration of the effective group was 0 (0-7.00) years and that of the ineffective group was 0 (0-4.83) years. There was no significant difference between the effective group and the ineffective group (t=1.662, 0.860; P=0.104, 0.395). In the effective group and the ineffective group, 12 cases and 9 cases used less than 2 kinds of antiepileptic drugs, 7 cases and 15 cases used more than or equal to 2 kinds of antiepileptic drugs, 13 and 15 cases had first epilepsy, 6 and 9 cases had non-first epilepsy, 14 and 11 cases had mtDNA variation, 5 and 13 cases had nDNA variation, respectively. There was no significant difference between the two groups (χ²=2.794, 0.164, 3.380; P=0.095, 0.686, 0.066). Conclusions The types of seizures with mitochondrial epilepsy in children varied, with focal motor seizures being the most common, followed by generalized or secondary generalized tonic-clonic seizures. Most children have more than two types of seizures. MELAS is the most common clinical phenotype, followed by LS; mtDNA variation is the dominant gene variation, of which m.3243A>G variation is the most common hotspot variation, followed by gene variation encoding mitochondrial aminoacyl tRNA synthase.

To summarize the clinical and genetic characteristics of children with mitochondrial epilepsy. Methods Clinical data of 62 children who were clinically and genetically diagnosed with mitochondrial epilepsy by the Department of Neurology, Beijing Children's Hospital from October 2011 to December 2018 were analyzed retrospectively, and the control of epilepsy was followed up. T test or χ2 test were used to analyze the related factors affecting the prognosis of epilepsy between the effective group and the ineffective group. Results Of the 62 patients, 33 were male and 29 were female. The age of onset was 3.38 (0-12.00) years; for the type of seizures, 68% (42/62) of the patients had focal seizures, generalized or secondary generalized tonic?clonic seizures were seen in 32% (20/62), myoclonic seizures in 23% (14/62), spastic seizures in 7 cases, tonic seizures in 4 cases, absence seizure, atonic seizure and clonic seizure in 1 case each; 16 cases (26%) had status epilepticus, of whom 6 cases had epilepsia partialis continua; 52% (32/62) had 2 or more types of seizures. The clinical phenotypes were mitochondrial encephalopathy, lactic acidosis, and stroke?like episodes (MELAS) in 29 cases, Leigh syndrome (LS) in 11 cases, combined oxidative phosphorylation deficiency in 6 cases, myoclonus epilepsy with ragged?red fibers in 5 cases, Alpers syndrome in 4 cases, pontocerebellar hypoplasia type 6 and mitochondrial DNA depletion syndrome 9 in 2 cases each, mitochondrial complex Ⅰ deficiency nuclear type 20, progressive cavitating leukoencephalopathy, and biotinidase deficiency in 1 case each. Of the 62 cases, 40 cases (65%) had mitochondrial DNA (mtDNA) variations, of which 26 cases had m. 3243A>G variants, 6 cases had m. 8344A>G variants, and 3 cases had m. 8993T>G/C variants, m. 3271T>C, m. 3481G>A, m. 3946G>A, m.13094T>C, m.14487T>C variant was in 1 case each; nuclear DNA (nDNA) variations were identified in 22 cases (35%), of which 7 cases carrying variations in mitochondrial ammonia acyl tRNA synthetase coding gene, mutations in POLG and the gene encoding complexⅠwere in 4 cases each, variations in SUCLG1 and SDHA genes were in 2 cases each, and variations in PDHA1, BTD and TRIT1 genes were in 1 case each. Forty?three patients were followed up, and the follow?up time was 20 (3-84) months. According to the follow?up results, the anti?epilepsy treatment was effective in 19 cases (44%) and ineffective in other 24 cases (56%). The onset age of the effective group was 3.42 (0-11.50) years and that of the ineffective group was 0.92 (0-9.50) years. The onset duration of the effective group was 0 (0-7.00) years and that of the ineffective group was 0 (0-4.83) years. There was no significant difference between the effective group and the ineffective group (t=1.662, 0.860; P=0.104, 0.395). In the effective group and the ineffective group, 12 cases and 9 cases used less than 2 kinds of antiepileptic drugs, 7 cases and 15 cases used more than or equal to 2 kinds of antiepileptic drugs, 13 and 15 cases had first epilepsy, 6 and 9 cases had non?first epilepsy, 14 and 11 cases had mtDNA variation, 5 and 13 cases had nDNA variation, respectively. There was no significant difference between the two groups (χ2 =2.794, 0.164, 3.380; P=0.095, 0.686, 0.066). Conclusions The types of seizures with mitochondrial epilepsy in children varied, with focal motor seizures being the most common, followed by generalized or secondary generalized tonic?clonic seizures. Most children have more than two types of seizures. MELAS is the most common clinical phenotype, followed by LS; mtDNA variation is the dominant gene variation, of which m.3243A>G variation is the most common hotspot variation, followed by gene variation encoding mitochondrial aminoacyl tRNA synthase.

Objective To investigate the clinical features and gene diagnostic bases of childhood L-2 -hydroxyglutaric aciduria (L-2-HGA). Methods The clinical data involving manifestations,laboratory examinations of 4 children with L-2-HGA admitted to Beijing Children′s Hospital Affiliated to Capital Medical University from April 2015 to March 2018 were retrospectively analyzed. Each patient had a follow-up visit ranging from 3 months to 3 years and 2 months after initial examination. Results The 4 patients,of whom 2 were siblings,consisted of 1 male and 3 females,whose age of onset ranged from 8 months old to 3 years old. All of them presented with seizures as their initial symptom. The developmental milestones were all normal before onset,while 3 cases gradually became mentally stagnant. Other symptoms included unsteady gait in 3 cases,slight hand trembling when holding items in 2 cases,and pyramidal impairment in 2 cases. Bilateral symmetric abnormalities in subcortical white matter,basal ganglia and dentate nucleus were detected by cranial magnetic resonance imaging (MRI)in all patients,and cerebral and cerebellar atrophy was ob-served in 1 case. Organic acid analysis by gas chromatography/ mass spectrometry (GC/ MS)demonstrated notable ele-vation of urinary 2-hydroxyglutaric acid in 3 cases. Pathogenic mutations on L2HGDH gene were detected by target -capture high-throughput sequencing in all 4 patients. The compound heterozygous mutations of c. 845G > A (p. Arg282Gln)and c. 800_801delCA (p. Ser267Ter)were identified in case 1,the homozygous missense mutation of c. 584A > G (p. Tyr195Cys ) in case 2 and case 3,and the homozygous frameshift mutation of c. 407delA (p. Lys136SerfsTer3)in case 4. The variants of c. 800_801delCA and c. 407delA were novel mutations firstly reported in this study. Sanger sequencing verified that parents of the 4 cases were all heterozygous carriers. The follow-up study in 2 cases who were put on high dosage of vitamin B2 and L-carnitine had shown a relatively favorable outcome of mild remission in ataxia and absence of mental degradation and further seizures,while the other 2 cases without specific therapy remained relatively stable. Conclusions The main clinical manifestations of L-2-HGA are mental retarda-tion,seizures and ataxia. Bilateral symmetric abnormalities in subcortical white matter,basal ganglia and dentate nucleus are specific neuroimaging findings. Significant elevation of urinary 2-hydroxyglutaric acid is the basic feature of the disease,while gene assessment should be the gold standard in the diagnosis of L-2-HGA. Treatment with high dosage of vitamin B2 and L-carnitine might be effective to partial patients.

Objective: To summarize the detailed clinical characteristics and genetic features of benign infantile epilepsy with PRRT2 mutation, in order to improve the understanding of the disease. Methods: The clinical data and genetic results of 40 benign infantile epilepsy patients with PRRT2 mutation who were diagnosed and treated in the neurology department of National Center for Children's Health (Beijing) , Beijing Children's Hospital affiliated to Capital Medical University from January 2002 to October 2017 and their affected family members were analyzed. Results: Forty benign infantile epilepsy patients were recruited for this study, with 18 males and 22 females. The age at onset ranged from 3 to 15 months (median: 4.6 months). All patients presented focal seizures with or without secondary generalization. Decreased responsiveness, eyes stare and cyanosis were commonly observed. A cluster of seizures was observed in 20 patients at the beginning of the disease, but interictal clinical conditions were normal. Interictal electroencephalograms were normal in 32 cases but 8 cases showed small amount scattered spike and spike wave. Two patients developed paroxysmal kinesigenic dyskinesia in 30 months and 12 years respectively after the cessation of the seizure. Thirty-four affected pedigree members had a history of paroxysmal episodes in 24 families, including 19 individuals of infantile afebrile convulsion, 6 individuals of paroxysmal kinesigenic dyskinesia during childhood or adulthood, 8 individuals of infantile convulsion and paroxysmal kinesigenic dyskinesia during adulthood, one individual of infantile febrile convulsion. The follow-up time ranged from 6 months to 15 years. Thirty-six patients were treated with antiepileptic drugs and their seizures were easy to control. Four patients stayed seizure free without medication (all <2 years). Seizure stopped in 24 patients within 1 year of age, in 10 patients stopped during 12-24 months and in 2 patients stopped during 24-36 months. All cases had PRRT2 mutations, 7 cases of a complete PRRT2 deletion, 33 cases of PRRT2 heterozygous mutations consisted of 28 frameshift mutations and 5 missense mutations. Of these heterozygous mutations, 30 cases were hereditary mutations while 3 were de novo mutations. Nine family members harbored the same PRRT2 mutations without any symptom. Conclusions Benign infantile epilepsy with PRRT2 mutation is characterized by early onset of seizure mostly before 6 months, focal seizures with or without secondary generalization, a high incidence of a cluster of seizures, rapid resolution of seizure by antiepileptic drugs and cessation of seizure mostly before 2 years of age. Partial patients may develop paroxysmal kinesigenic dyskinesia increasing with age. Most PRRT2 gene mutations are heterozygous mutations, and a few are the overall deletion of PRRT2 gene.

OBJECTIVETo observe the efficacy and safety of atomoxetine hydrochloride in children with narcolepsy.

METHODTotally 66 patients with narcolepsy who were conformed international classification of sleep disturbances (ICSD-2) diagnostic criteria treated with atomoxetine hydrochloride seen from November 2010 to December 2014 were enrolled into this study, 42 of them were male and 24 female, mean age of onset was 7.5 years (3.75-13.00 years), mean duration before diagnosis was 1.75 years (0.25-5.00 years). Complete blood count, liver and kidney function, multiple sleep latency test (MSLT), polysomnography (PGS), neuroimaging and electroencephalography (EEG) were performed for each patient. For some of the children HLA-DR2 gene and serum markers of infection were tested. The 66 cases were followed up from 2 to 49 months (average 18 months) to observe the clinical efficacy and adverse reactions.

RESULTSIn 62 cases excessive daytime sleepiness was improved, in 11 cases (16.7%) it was controlled (16.7%), in 29 cases (43.9%) the treatment was obviously effective and in 22 (33.3%) it was effective; cataplexy occurred in 54 cases, in 18 (33.3%) it was controlled, in 19 (35.2%) the treatment was obviously effective and in 10 (18.5%) effective; night sleep disorders existed in 55 cases, in 47 cases it was improved, in 14 (25.5%) it was controlled, in 20 (36.4%) the treatment was obviously effective and in 13 (23.6%) effective; hypnagogic or hypnopompic hallucination was present in 13 cases, in only 4 these symptoms were controlled. Sleep paralysis existed in 4 cases, it was controlled in only 1 case. In 18 cases attention and learning efficiency improved.Anorexia occurred in 18 cases, mood disorder in 5 cases, depression in 2 cases, nocturia, muscle tremors, involuntary tongue movement each occurred in 1 case. P-R interval prolongation and atrial premature contraction were found in 1 case.

CONCLUSIONAtomoxetine hydrochloride showed good effects in patients with narcolepsy on excessive daytime sleepiness, cataplexy and night sleep disorders, the effects on hallucinations and sleep paralysis were not significant. Adverse reactions were slight, anorexia and mood disorder were common. As a non-central nervous system stimulant, atomoxetine hydrochloride does not induce drug dependence and has no prescription limits; it has good tolerability, safety and effectiveness, it can be a good alternative in treatment of children with narcolepsy.

Adolescent ; Atomoxetine Hydrochloride ; adverse effects ; therapeutic use ; Cataplexy ; drug therapy ; Child ; Child, Preschool ; Electroencephalography ; Female ; Humans ; Male ; Narcolepsy ; drug therapy ; Neuroimaging ; Polysomnography