Objective:To investigate the clinical manifestations of medically refractory hereditary movement disorders in children and the efficacy of deep brain stimulation (DBS).Methods:A case series study.The clinical and follow-up data of 20 children with medically refractory hereditary movement disorders who underwent DBS treatment at the Neurology and Functional Neurosurgery Departments of Beijing Children′s Hospital, Capital Medical University, from July 2018 to April 2024, were retrospectively analyzed.The severity of movement disorder symptoms and surgical effects were evaluated using the Burke-Fahn-Marsden Dystonia Rating Scale Movement(BFMDRS-M) or the Unified Parkinson′s Disease Rating Scale Ⅲ(UPDRS Ⅲ).Results:There were 12 males and 8 females among the 20 children, with an onset age ranging from 4 months to 12 years and 5 months.Fourteen patients had hereditary dystonia, which is related to KMT2B in 11 patients, TOR1A in 2 patients and SGCE in 1 patient.Two patients had choreoathetosis, which is related to ADCY5-related familial movement disorders.Two patients had early-onset Parkinson′s disease, which is related to ATP6AP2 in 1 patient and VPS13C in 1 patient.Two patients had neurodevelopmental disorders with involuntary movements, which is related to GNAO1 in 1 patient, and the other patient was idiopathic.All the children were given oral Levodopa, Benzhexol, Baclofen, Tiapride Hydrochloride, Clonazepam alone or in combination.Three children showed obvious dyskinesia after Levodopa treatment.The symptoms of movement disorders in all children exhibited little to no improvement.Levetiracetam and Zonisamide had unstable effects in the treatment of myoclonia.DBS surgery was performed on all the patients aged from 3 to 16 years.Electrodes were successfully inserted into bilateral globus pallidus internus in 14 cases and bilateral subthalamic nuclei in 4 cases.The target was unknown in 2 cases.No surgery-related complications were observed.The patients were followed up for 3 months to 6 years, and the last follow-up age of the patients ranged from 5 years and 7 months to 22 years and 1 month.The rate of improvement in BFMDRS-M score was 37%-100% in 16 patients and >70% in 7 patients with hereditary dystonia.The rate of improvement in UPDRS Ⅲ score was 23% in 1 patient with VPS13C-related early-onset Parkinson′s disease. Conclusions:Childhood medically refractory hereditary movement disorders are a case series that exhibits significant phenotypic and genotypic heterogeneity.DBS surgery demonstrates significant efficacy for KMT2B-, TOR1A-, and SGCE-related hereditary movement disorders.

Objective:To investigate the clinical manifestations of medically refractory hereditary movement disorders in children and the efficacy of deep brain stimulation (DBS).Methods:A case series study.The clinical and follow-up data of 20 children with medically refractory hereditary movement disorders who underwent DBS treatment at the Neurology and Functional Neurosurgery Departments of Beijing Children′s Hospital, Capital Medical University, from July 2018 to April 2024, were retrospectively analyzed.The severity of movement disorder symptoms and surgical effects were evaluated using the Burke-Fahn-Marsden Dystonia Rating Scale Movement(BFMDRS-M) or the Unified Parkinson′s Disease Rating Scale Ⅲ(UPDRS Ⅲ).Results:There were 12 males and 8 females among the 20 children, with an onset age ranging from 4 months to 12 years and 5 months.Fourteen patients had hereditary dystonia, which is related to KMT2B in 11 patients, TOR1A in 2 patients and SGCE in 1 patient.Two patients had choreoathetosis, which is related to ADCY5-related familial movement disorders.Two patients had early-onset Parkinson′s disease, which is related to ATP6AP2 in 1 patient and VPS13C in 1 patient.Two patients had neurodevelopmental disorders with involuntary movements, which is related to GNAO1 in 1 patient, and the other patient was idiopathic.All the children were given oral Levodopa, Benzhexol, Baclofen, Tiapride Hydrochloride, Clonazepam alone or in combination.Three children showed obvious dyskinesia after Levodopa treatment.The symptoms of movement disorders in all children exhibited little to no improvement.Levetiracetam and Zonisamide had unstable effects in the treatment of myoclonia.DBS surgery was performed on all the patients aged from 3 to 16 years.Electrodes were successfully inserted into bilateral globus pallidus internus in 14 cases and bilateral subthalamic nuclei in 4 cases.The target was unknown in 2 cases.No surgery-related complications were observed.The patients were followed up for 3 months to 6 years, and the last follow-up age of the patients ranged from 5 years and 7 months to 22 years and 1 month.The rate of improvement in BFMDRS-M score was 37%-100% in 16 patients and >70% in 7 patients with hereditary dystonia.The rate of improvement in UPDRS Ⅲ score was 23% in 1 patient with VPS13C-related early-onset Parkinson′s disease. Conclusions:Childhood medically refractory hereditary movement disorders are a case series that exhibits significant phenotypic and genotypic heterogeneity.DBS surgery demonstrates significant efficacy for KMT2B-, TOR1A-, and SGCE-related hereditary movement disorders.

Objective:To summarize the clinical and prognostic features of children with opsoclonus-myoclonus-ataxia syndrome (OMAS).Methods:A total of 46 patients who met the diagnostic criteria of OMAS in the Department of Neurology, Beijing Children′s Hospital from June 2015 to June 2023 were retrospectively analyzed. Centralized online consultations or telephone visits were conducted between June and August 2023. The data of the children during hospitalization and follow-up were collected, including clinical manifestations, assistant examination, treatment and prognosis. According to the presence or absence of tumor, the patients were divided into two groups. The chi-square test or Mann-Whitney U test was used to compare the differences between the two groups. Univariate Logistic regression was used to analyze the factors related to OMAS recurrence and prognosis. Results:There were 46 patients, with 25 males and the onset age of 1.5 (1.2, 2.4) years. Twenty-six (57%) patients were diagnosed with neuroblastoma during the course of the disease, and no patients were categorized into the high-risk group. A total of 36 patients (78%) were followed up for≥6 months, and all of them were treated with first-line therapy with glucocorticoids, gammaglobulin and (or) adrenocorticotrophic hormone. Among the 36 patients, 9 patients (25%) were treated with second-line therapy for ≥3 months, including rituximab or cyclophosphamide, and 17 patients (47%) received chemotherapy related to neuroblastoma. At the follow-up time of 4.2 (2.2, 5.5) years, 10 patients (28%) had relapsed of OMAS. The Mitchell and Pike OMS rating scale score at the final follow-up was 0.5 (0, 2.0). Seven patients (19%) were mildly cognitively behind their peers and 6 patients (17%) were severely behind. Only 1 patient had tumor recurrence during follow-up. The history of vaccination or infection before onset was more common in the non-tumor group than in the tumor group (55%(11/20) vs. 23%(6/26), χ2=4.95, P=0.026). Myoclonus occurred more frequently in the non-tumor group (40%(8/20) vs. 4%(1/26), χ2=7.23, P=0.007) as the onset symptom. Univariate Logistic regression analysis showed that the tumor group had less recurrence ( OR=0.19 (0.04-0.93), P=0.041). The use of second-line therapy or chemotherapy within 6 months of the disease course had a better prognosis ( OR=11.64 (1.27-106.72), P=0.030). Conclusions:OMAS in children mostly starts in early childhood, and about half are combined with neuroblastoma. Neuroblastoma in combination with OMAS usually has a low risk classification and good prognosis. When comparing patients with OMAS with and without tumors, the latter have a more common infection or vaccination triggers, and myoclonus, as the onset symptom, is more common. Early addition of second-line therapy is associated with better prognosis in OMAS.

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.

The male patient of middle-age was admitted to Zhujiang Hospital, Southern Medical University on September 5, 2020, due to wear and rupture of the left foot hallux for more than 10 days, gradually developed swelling and blackening of the left foot and accompanied by drowsiness for 1day. Results from etiological examination of his wound secretions suggested the mixed infection of Wohlfahrtiimonas chitiniclastica and Enterococcus faecalis. The disease progressed rapidly and the patient still died of septic shock after anti-infective treatment. The infection of W. chitiniclastica is rare and has a great relationship with poor hygiene and chronic open wounds. It is necessary to use matrix-assisted laser desorption/ionization-time of flight mass spectrometry or 16S ribosomal RNA gene sequencing for strain identification. Moreover, it is recommended to use cephalosporins or carbapenems as first-line drugs due to the poor prognosis of patients with bloodstream infections.

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.

The CACNA1A gene encodes a voltage-gated calcium channel of the pore-forming protein, which has important functions in the central nervous system.The CACNA1A gene mutation can lead to a variety of neurological diseases, including familial hemiplegic migraine 1, spinocerebellar ataxia 6, episodic ataxia 2 and early infantile epileptic encephalopathy 42.Overlapping phenotypes could be observed in a small number of patients.This review summarized the clinical and genetic characteristics of the CACNA1A gene mutation.