Objective To study the association between maternal reduced folate carrier (RFC) gene polymorphisms and congenital heart disease (CHD) in offspring. Methods A hospital-based case-control study was conducted. The mothers of 683 infants with CHD who attended the Department of Cardiothoracic Surgery, Hunan Children's Hospital, from November 2017 to March 2020 were enrolled as the case group. The mothers of 740 healthy infants without any deformity who attended the hospital during the same period of time were enrolled as the control group. A questionnaire survey was performed to collect the exposure data of subjects. Venous blood samples of 5 mL were collected from the mothers for genetic polymorphism detection. A multivariate logistic regression analysis was used to evaluate the association of RFC gene polymorphisms and their haplotypes with CHD. A generalized multifactor dimensionality reduction method was used to analyze gene-gene interactions. Results After control for confounding factors, the multivariate logistic regression analysis showed that maternal RFC gene polymorphisms at rs2236484 (AG vs AA:OR=1.91, 95%CI:1.45-2.51; GG vs AA: OR=1.96, 95%CI:1.40-2.75) and rs2330183 (CT vs CC:OR=1.39, 95%CI:1.06-1.83) were significantly associated with the risk of CHD in offspring. The haplotypes of G-G (OR=1.21, 95%CI:1.03-1.41) and T-G (OR=1.25, 95%CI:1.07-1.46) in mothers significantly increased the risk of CHD in offspring. The interaction analysis showed significant gene-gene interactions between different SNPs of the RFC gene in CHD (P < 0.05). Conclusions Maternal RFC gene polymorphisms and interactions between different SNPs are significantly associated with the risk of CHD in offspring.

Objective To investigate the incidence rate and risk factors for metabolic bone disease of prematurity (MBDP) in very low birth weight/extremely low birth weight (VLBW/ELBW) infants. Methods The medical data of 61 786 neonates from multiple centers of China between September 1, 2013 and August 31, 2016 were retrospectively investigated, including 504 VLBW/ELBW preterm infants who met the inclusion criteria. Among the 504 infants, 108 infants diagnosed with MBDP were enrolled as the MBDP group and the remaining 396 infants were enrolled as the non-MBDP group. The two groups were compared in terms of general information of mothers and preterm infants, major diseases during hospitalization, nutritional support strategies, and other treatment conditions. The multivariate logistic regression analysis was used to investigate the risk factors for MBDP. Results The incidence rate of MBDP was 19.4% (88/452) in VLBW preterm infants and 38.5% (20/52) in ELBW preterm infants. The incidence rate of MBDP was 21.7% in preterm infants with a gestational age of < 32 weeks and 45.5% in those with a gestational age of < 28 weeks. The univariate analysis showed that compared with the non-MBDP group, the MBDP group had significantly lower gestational age and birth weight, a significantly longer length of hospital stay, and a significantly higher incidence rate of extrauterine growth retardation (P < 0.05). Compared with the non-MBDP group, the MBDP group had significantly higher incidence rates of neonatal sepsis, anemia, hypocalcemia, and retinopathy of prematurity (P < 0.05). The MBDP group had a significantly lower mean feeding speed, a significantly higher age when reaching total enteral feeding, and a significantly longer duration of parenteral nutrition (P < 0.05). The use rate of caffeine citrate in the MBDP group was significantly higher, but the use rate of erythropoietin was significantly lower than that in the non-MBDP group (P < 0.05). The multivariate logistic regression analysis showed that gestational age < 32 weeks, hypocalcemia, extrauterine growth retardation at discharge, and neonatal sepsis were risk factors for MBDP (P < 0.05). Conclusions A lower gestational age, hypocalcemia, extrauterine growth retardation at discharge, and neonatal sepsis may be associated an increased risk of MBDP in VLBW/ELBW preterm infants. It is necessary to strengthen perinatal healthcare, avoid premature delivery, improve the awareness of the prevention and treatment of MBDP among neonatal pediatricians, and adopt positive and reasonable nutrition strategies and comprehensive management measures for preterm infants.

Objective To study the association of neonatal blood calcium levels with perinatal factors and neonatal urinary calcium levels measured by an intelligent urine test system. Methods The medical data of 96 full-term singleton neonates with mild diseases were collected by a cross-sectional survey, who were hospitalized in the Department of Neonatology, The First Affiliated Hospital of Xi'an Jiaotong University, from June to August 2018. Urinary calcium levels measured by an intelligent urine test system, total blood calcium levels, ionized calcium levels, and the mother's calcium and vitamin D supplementation during pregnancy were recorded. Results Compared with the group without vitamin D supplementation for the mother (17 neonates), the group with vitamin D supplementation for the mother (79 neonates) had significantly higher levels of total blood calcium and ionized calcium (P < 0.05).The group with both vitamin D and calcium supplementation for the mother (68 neonates) had significantly higher levels of ionized calcium than controls (28 neonate) (P=0.05). There was no significant difference in the levels of total blood calcium and ionized calcium between the group with calcium supplementation for the mother (74 neonates) and the group without calcium supplementation for the mother (22 neonates) (P > 0.05). The hypothermia group (5 neonates) had a significantly lower level of total blood calcium than the normal body temperature group (91 neonates) (P < 0.05). There was a significantly positive correlation between the maternal blood total calcium level and the neonatal blood total calcium and ionized calcium levels (r=0.881 and 0.703 respectively; P < 0.05). The neonatal urinary calcium level measured by the intelligent urine test system was significantly correlated with the blood ionized calcium level (r=0.526, P=0.025). Conclusions Vitamin D supplementation during pregnancy can increase the blood levels of total calcium and ionized calcium in neonates, and calcium supplementation alone cannot increase the blood levels of total calcium or ionized calcium in neonates. Hypothermia in neonates might cause the reduction in blood calcium levels. The urinary calcium level measured by the intelligent urine test system is positively correlated with the blood level of ionized calcium.

Objective To study the risk factors for the first ventilator weaning failure and the relationship between the weaning failure and prognosis in preterm infants receiving invasive mechanical ventilation. Methods A retrospective analysis was performed for the preterm infants who were admitted to the Neonatal Intensive Care Unit of Peking University Third Hospital and received mechanical ventilation within 72 hours after birth. According to whether reintubation was required within 72 hours after the first weaning, the infants were divided into a successful weaning group and a failed weaning group. Results A total of 282 preterm infants were enrolled, and there were 43 infants (15.2%) in the failed weaning group. Compared with the successful weaning group, the failed weaning group had significantly lower gestational age and birth weight (P < 0.05), a significantly higher rate of intubation in the delivery room (P < 0.05), and a significantly higher proportion of infants with patent ductus arteriosus (PDA; diameter ≥ 2.5 mm) (P < 0.05). Use of ≥ 2 vasoactive agents before ventilator weaning (OR=2.48, 95%CI:1.22-5.03, P < 0.05) and PDA (≥ 2.5 mm) (OR=4.54, 95%CI:2.02-10.24, P < 0.05) were risk factors for ventilator weaning failure. Compared with the successful weaning group, the failed weaning group had significantly higher incidence rates of ventilator-associated pneumonia, moderate-to-severe bronchopulmonary dysplasia, and sepsis (P < 0.05). The oxygen inhalation time and hospital stay in the failed weaning group were significantly longer than those in the successful weaning group (P < 0.05). Conclusions Use of ≥ 2 vasoactive agents before ventilator weaning and PDA (≥ 2.5 mm) are risk factors for ventilator weaning failure, and ventilator weaning failure may be associated with adverse outcomes in hospitalized preterm infants.

Objective To study the clinical features of very preterm infants with prelabor rupture of membranes (PROM) and predictive factors for early-onset sepsis (EOS) and death. Methods A retrospective analysis was performed for the clinical data of the very preterm infants with PROM (with a gestational age of < 32 weeks) who were admitted to the neonatal intensive care unit from January 2018 to May 2020. According to the time from membrane rupture to delivery, the infants were divided into four groups: < 18 hours (n=107), 18 hours to < 3 days (n=111), 3 days to < 14 days (n=144), and ≥ 14 days (n=37). According to the presence or absence of EOS, the infants were divided into EOS (n=42) and non-EOS groups (n=357). According to the survival state, the infants were divided into a survival group (n=359) and a death group (n=40). Clinical features were analyzed for very preterm infants with different times of PROM. A multivariate logistic regression analysis was used to investigate the predictive factors for EOS and death in very preterm infants with PROM. Results There was no significant difference in the incidence rates of major neonatal complications and mortality rate among the very preterm infants with different times of PROM (P > 0.05). Birth weight < 1 000 g (OR=4.353, P=0.042), grade Ⅲ amniotic fluid contamination (OR=4.132, P=0.032), and grade Ⅲ-Ⅳ respiratory distress syndrome (RDS) (OR=2.528, P=0.021) were predictive factors for EOS in very preterm infants with PROM. Lower birth weights (< 1 000 g or 1 000-1 499 g; OR=11.267 and 3.456 respectively; P=0.004 and 0.050 respectively), grade Ⅲ-Ⅳ RDS (OR=5.572, P < 0.001), and neonatal sepsis (OR=2.631, P=0.012) were predictive factors for death in very preterm infants with PROM. Conclusions Prolonged PROM does not increase the incidence of neonatal complications and mortality in very preterm infants. Adverse outcomes of very preterm infants with PROM are mainly associated with lower birth weights, lung immaturity, and systemic infection.

Objective To evaluate the efficacy of sepsis risk calculator (SRC) in guiding antibiotic use in neonates with suspected early-onset sepsis (EOS). Methods A total of 284 neonates with a gestational age of ≥ 35 weeks were enrolled as the control group, who were hospitalized in the Children's Hospital of Chongqing Medical University from March to July, 2019 and were suspected of EOS. Their clinical data were retrospectively collected and the use of antibiotics was analyzed based on SRC. A total of 170 neonates with a gestational age of ≥ 35 weeks were enrolled as the study group, who were admitted to the hospital from July to November, 2020 and were suspected of EOS. SRC was used prospectively for risk scoring to assist the decision making of clinical antibiotic management. The two groups were compared in terms of the rate of use of antibiotics, blood culture test rate, clinical outcome, and adherence to the use of SRC. Results Compared with the control group, the study group had a significantly higher SRC score at birth and on admission (P < 0.05). The rate of use of antibiotics in the study group was significantly lower than that in the control group[84.7% (144/170) vs 91.5% (260/284), 6.8% decrease; P < 0.05]. The blood culture test rate in the study group was also significantly lower than that in the control group (85.3% vs 91.9%, P < 0.05). There was no significant difference between the two groups in the incidence rate of adverse outcomes and the final diagnosis of EOS (P > 0.05). Conclusions The use of SRC reduces the rate of empirical use of antibiotics in neonates with suspected EOS and does not increase the risk of adverse outcomes, and therefore, it holds promise for clinical application.

Objective To investigate the factors contributing to the withdrawal from treatment in neonates with respiratory failure. Methods The medical data of 2 525 neonates with respiratory failure were retrospectively studied, who were reported in 30 hospitals of Jiangsu Province from January to December, 2019. According to whether a complete treatment was given, they were divided into a complete treatment group with 2 162 neonates and a withdrawal group with 363 neonates. A multivariate logistic regression analysis was used to investigate the factors contributing to the withdrawal from treatment in neonates with respiratory failure. Results The multivariate logistic regression analysis showed that small-for-gestational-age birth, congenital abnormality, gestational age < 28 weeks, living in the rural area or county-level city, and maternal age < 25 years were risk factors for the withdrawal from treatment in neonates with respiratory failure (P < 0.05), while a higher 5-minute Apgar score and cesarean section were protective factors (P < 0.05). Furthermore, 176 answers were obtained from 160 parents of the neonates who were willing to tell the reason for the withdrawal from treatment, among which severe sequelae (44.9%, 79/176) had the highest frequency, followed by uncontrollable disease condition (24.4%, 43/176), family financial difficulties (18.2%, 32/176), and dependence on mechanical ventilation (12.5%, 22/176). Conclusions Small-for-gestational-age birth, congenital abnormality, gestational age, living area, maternal age, Apgar score at birth, and method of birth are contributing factors for the withdrawal from treatment in neonates with respiratory failure. A poor prognosis and a low quality of life in future might be major immediate causes of withdrawal from treatment in neonates with respiratory failure, which needs to be confirmed by further studies.

Objective To evaluate the clinical features of preterm infants with a birth weight less than 1 500 g undergoing different intensities of resuscitation. Methods A retrospective analysis was performed for the preterm infants with a birth weight less than 1 500 g and a gestational age less than 32 weeks who were treated in the neonatal intensive care unit of 20 hospitals in Jiangsu, China from January 2018 to December 2019. According to the intensity of resuscitation in the delivery room, the infants were divided into three groups:non-tracheal intubation (n=1 184), tracheal intubation (n=166), and extensive cardiopulmonary resuscitation (ECPR; n=116). The three groups were compared in terms of general information and clinical outcomes. Results Compared with the non-tracheal intubation group, the tracheal intubation and ECPR groups had significantly lower rates of cesarean section and use of antenatal corticosteroid (P < 0.05). As the intensity of resuscitation increased, the Apgar scores at 1 minute and 5 minutes gradually decreased (P < 0.05), and the proportion of infants with Apgar scores of 0 to 3 at 1 minute and 5 minutes gradually increased (P < 0.05). Compared with the non-tracheal intubation group, the tracheal intubation and ECPR groups had significantly higher mortality rate and incidence rates of moderate-severe bronchopulmonary dysplasia and serious complications (P < 0.05). The incidence rates of grade Ⅲ-Ⅳ intracranial hemorrhage and retinopathy of prematurity (stage Ⅲ or above) in the tracheal intubation group were significantly higher than those in the non-tracheal intubation group (P < 0.05). Conclusions For preterm infants with a birth weight less than 1 500 g, the higher intensity of resuscitation in the delivery room is related to lower rate of antenatal corticosteroid therapy, lower gestational age, and lower birth weight. The infants undergoing tracheal intubation or ECRP in the delivery room have an increased incidence rate of adverse clinical outcomes. This suggests that it is important to improve the quality of perinatal management and delivery room resuscitation to improve the prognosis of the infants.

Objective To study the efficacy of probiotics in preventing late-onset sepsis (LOS) in very low birth weight (VLBW) infants. Methods Databases including PubMed, Web of Science, Cochrane Library, Wanfang Data, China National Knowledge Infrastructure, and Chinese Biomedical Literature Database were searched for randomized controlled trials (RCTs) of probiotics in preventing LOS in VLBW infants. LOS was classified as clinical LOS and confirmed LOS. RevMan 5.4 was used to perform the Meta analysis. Results A total of 31 RCTs were included, with 3 490 VLBW infants in the probiotics group and 3 376 VLBW infants in the control group. The Meta analysis showed that compared with the control group, the probiotics group had significantly lower risks of clinical LOS (RR=0.79, 95%CI:0.66-0.94, P=0.009) and clinical/confirmed LOS (RR=0.79, 95% CI:0.67-0.94, P=0.007). In the probiotics group, the infants receiving exclusive breastfeeding had a significantly lower risk of confirmed LOS (RR=0.77, 95%CI:0.62-0.96, P=0.02). Conclusions Current evidence indicates that probiotics may reduce the risk of clinical LOS and clinical/confirmed LOS in VLBW infants, and the risk of confirmed LOS in VLBW infants who are exclusively breastfed.

Objective To study the effect of rehabilitation treatment based on the International Classification of Functioning, Disability and Health-Children and Youth Version (ICF-CY) Core Sets on activities of daily living in children with cerebral palsy. Methods The children with cerebral palsy were divided into an observation group (n=63) and a control group (n=59) using a random number table. The children in the observation group were evaluated using the brief ICF-CY Core Sets for children under 6 years to identify intervention targets and develop rehabilitation plans and goals, and then specific methods were selected for rehabilitation treatment. The children in the control group were evaluated and treated with the traditional rehabilitation mode. The scores of the Functional Independence Measure for Children (WeeFIM) and the Infants-Junior Middle School Students' Social-Life Abilities Scale were assessed for both groups before treatment and after three courses of treatment. The intervention of environmental factors was compared between the two groups. Results There was no significant difference in the scores of the WeeFIM and Social-Life Abilities scales between the two groups before treatment (P > 0.05). After treatment, both groups had significant increases in the scores of the WeeFIM and Social-Life Abilities scales (P < 0.001). The observation group had significantly higher scores of WeeFIM and Social-Life Abilities scales than the control group after treatment (P < 0.05). There was no significant difference in the use rate of orthosis between the two groups (P > 0.05), but the use rate of assistive devices for self-help, transfer and communication, the rate of facility renovation, and the rate of family rehabilitation guidance in the observation group were significantly higher than those in the control group (P < 0.05). Conclusions The rehabilitation treatment regimen for cerebral palsy based on the CF-CY Core Sets pays more attention to the influence of environmental factors in the process of rehabilitation and can effectively improve the activities of daily living of children with cerebral palsy.

Objective To study the clinical features and prognosis of children with acute megakaryocytic leukemia (AMKL) and the clinical effect of acute myeloid leukemia 03 (AML03) regimen for the treatment of pediatric AMKL. Methods The clinical data were collected from 47 children with AMKL who were diagnosed from May 2011 to December 2019. The treatment outcomes and prognostic factors were analyzed. The Kaplan-Meier method and the log-rank test were used for survival analysis. Results Among the 47 children with AMKL, 22 with non-Down syndrome-AMKL were treated by the AML03 regimen, with a median follow-up time of 11.4 months. For the 22 non-Down syndrome-AMKL patients, the remission rate of bone marrow cytology was 85% and the negative rate of minimal residual disease (MRD) was 79% after induction Ⅱ, with a 2-year overall survival (OS) rate of (50±13)% and a 2-year event-free survival (EFS) rate of (40±12)%. The group with positive immunophenotypic marker CD56 had significantly lower 2-year EFS and OS rates than the group with negative CD56 (P < 0.05). The group without remission of bone marrow cytology after induction Ⅱ had significantly lower 2-year EFS and OS rates than the group with remission (P < 0.05). The group with positive MRD after induction Ⅱ had a significantly lower 2-year EFS rate than the group with negative MRD (P < 0.05). There was no significant difference in 2-year OS and EFS rates between the patients with transplantation and those without transplantation (P > 0.05). Conclusions Children with AMKL tend to have a low remission rate and a poor prognosis. Positive immunophenotypic marker CD56, bone marrow cytology during early treatment response, and MRD results are important factors influencing the prognosis. Allogeneic hematopoietic stem cell transplantation has no significant effect on the prognosis of AMKL.

Objective To study the efficacy and safety of intensity-modulated radiotherapy (IMRT) in children with high-risk neuroblastoma (NB). Methods A retrospective analysis was performed on the medical data of 24 children with high-risk NB who were diagnosed and treated with IMRT in the Department of Hematology and Oncology, Hunan Provincial People's Hospital, from April 2018 to December 2020. The medical data included age, radiotherapy dose, times of radiotherapy, laboratory examination results, adverse reactions, and survival. Results All 24 children (14 boys and 10 girls) received IMRT, with a mean age of (65±23) months and a median age of 59 months. The primary tumor was located in the abdomen in 23 children and 1 child had primary tumor in the mediastinum. The median age was 41.5 months at the time of radiotherapy. The radiation dose of radiotherapy ranged from 14.4 to 36.0 Gy, with a mean dose of (22±3) Gy and a daily dose of 1.8-2.0 Gy. The radiotherapy was performed for a total number of 8-20 times, with a mean number of 11.9 times. Among these children, 6 received radiotherapy for the residual or metastatic lesion. Of all the 23 children, 3 experienced cough, 2 experienced diarrhea, and 1 experienced vomiting during radiotherapy. At 2 weeks after radiotherapy, serum creatinine ranged from 2.3 to 70.1 μmol/L and alanine aminotransferase ranged from 9.1 to 65.3 μ/L. Ten children experienced grade Ⅲ bone marrow suppression and 2 experienced grade Ⅳ bone marrow suppression 1 to 2 weeks after radiotherapy. Four children experienced grade Ⅲ bone marrow suppression and 1 experienced grade Ⅳ bone marrow suppression 3 to 4 weeks after radiotherapy. During a median follow-up time of 13.5 months, 23 children (96%) achieved stable disease and 1 died. Up to the follow-up date, second malignant tumor or abnormal organ function was not observed. Conclusions IMRT can improve the local control rate of NB. IMRT appears to be safe in the treatment of children with NB.

Objective To study the mental health status of primary school students and the factors influencing the mental health status during the coronavirus disease 2019 (COVID-19) epidemic. Methods Online questionnaire surveys were conducted among 3 600 primary school students aged 6-12 years in Jilin Province, China in April, 2020 (during the epidemic) and 3 089 primary school students in September, 2020 (during the regular epidemic prevention and control). The general information and the data related to the Mental Health Scale for Child and Adolescent were collected by the questionnaire surveys. The multivariate logistic regression analysis was used to evaluate the factors influencing the mental health status of the students during the epidemic. Results The students during the epidemic had a significantly poorer mental health status in the emotional experience and volitional behavior than those during the regular epidemic prevention and control (P < 0.05). The multivariate logistic regression analysis showed the risk of psychological problems of the students decreased with age (OR=0.895). The girls were at a higher risk of psychological problems than boys (OR=1.453). The students with father's and mother's charater between irritability and gentle were at a lower risk of psychological problems (OR=0.496 and 0.470 respectively). The students from a family with a parental education style of a combination of encouraging and scolding were at a lower risk of psychological problems (OR=0.263). The students from a single-parent family or an extended family were at a higher risk of psychological problems (OR=2.995 and 3.446 respectively). Conclusions The COVID-19 epidemic has a certain impact on emotional experience and volitional behavior of primary school students. During the epidemic, particular attention should be paid to the mental health of primary school students, especially girls, younger students, and students from single-parent families, extended families or families with impatient parents and improper parental education.

A boy was admitted on day 3 after birth due to shortness of breath for 2 days and cyanosis for 1 day. He had clinical manifestations of dyspnea in the early postnatal period and situs inversus, and was finally diagnosed with Kartagener syndrome. His condition was improved after oxygen therapy, anti-infective therapy, and aerosol therapy. The genetic testing showed that there was a large-fragment loss of heterozygosity, exon 48_50, and a hemizygous mutation, c.7915C > T(p.R2639X), in the DNAH5 gene. Kartagener syndrome is a rare autosomal recessive disease, and this is the first case of Kartagener syndrome diagnosed in the neonatal period in China.

Objective To study the effect of dexamethasone (DEX) on the expression of Dynein heavy chain (DHC) and Dynactin in the cytoplasm of fetal rat cerebral cortical neurons cultured in vitro. Methods Primary cerebral cortical neurons of fetal rats were cultured in vitro and were used to establish a cellular model of DEX intervention. According to the final concentration of DEX, the neurons were divided into three groups:control (without DEX), 0.1 μmol/L DEX, and 1.0 μmol/L DEX. On days 1, 3, and 7 after intervention, the quantitative PCR was used to observe the effect of DEX on the mRNA expression of DHC and Dynactin. The Western blot was used to observe the effect of DEX on the protein expression of DHC and Dynactin. Results There was no significant difference in the mRNA expression levels of DHC and Dynactin among the three groups at all time points (P > 0.05). On day 7 after DEX intervention, the protein expression of DHC in the 1.0 μmol/L DEX group gradually increased and reached the peak over time, which was significantly higher than that in the control and 0.1 μmol/L DEX groups (P < 0.05). The control and 0.1 μmol/L DEX groups had a significant increase in the protein expression of Dynactin from day 1 to days 3 and 7 after DEX intervention (P < 0.05). The control group had a significant increase in the protein expression of Dynactin from day 3 to day 7 after intervention (P < 0.05), while the 0.1 μmol/L DEX group had a significant reduction in the protein expression of Dynactin from day 3 to day 7 after intervention (P < 0.05). On days 3 and 7 after DEX intervention, the 0.1 μmol/L DEX and 1.0 μmol/L DEX groups had a significantly lower protein expression level of Dynactin in the cerebral cortical neurons than the control group (P < 0.05). On day 7 after DEX intervention, the 1.0 μmol/L DEX group had a significantly lower protein expression level of Dynactin than the 0.1 μmol/L DEX group (P < 0.05). Conclusions DEX affects the protein expression of DHC and Dynactin in the fetal rat cerebral cortical neurons cultured in vitro, possibly in a concentration- and time-dependent manner.

Peak expiratory flow (PEF) is a portable, reliable, and inexpensive method for lung function assessment. PEF can reflect expiratory airflow limitation and its variability can document reversibility, which provides an objective basis for the diagnosis of asthma in children. Short-term PEF monitoring can be an important aid in the management of acute asthma exacerbations, identification of possible triggers, and assessment of response to treatment. Long-term PEF monitoring can assist in the assessment of asthma control and warning of acute exacerbations, and this is useful for children with severe asthma. This article reviews the measurements, influencing factors, interpretation, and application of PEF, and its role in the diagnosis and management of asthma in children, to provide references for the clinical application of PEF in children.

Neurodegeneration with brain iron accumulation (NBIA) is a group of rare neurogenetic degenerative diseases caused by genetic mutations and characterized by iron deposition in the central nervous system, especially in the basal ganglia, with an overall incidence rate of 2/1 000 000-3/1 000 000. Major clinical manifestations are extrapyramidal symptoms. This disease is presently classified into 14 different subtypes based on different pathogenic genes, and its pathogenesis and treatment remain unclear. This article summarizes the research advances in the pathogenesis and treatment of NBIA, so as to help pediatricians understand this disease and provide a reference for subsequent research on treatment.