Objective To investigate the influence of single nucleotide polymorphism (SNP) of methylenetetrahydrofolate reductase (MTHFR) and thiopurine S-methyltransferase (TPMT) on adverse reactions of chemotherapy in children patients with acute lymphocytic leukemia (ALL).Methods Ninety-eight children patients withALL in the pediatric department of this hospital from Jan.2014 to Dec.2016 were chosen.The gradient PCR and DNA sequencing were adopted to detect the genotypes of MTHFR C677T,A1298C and TPMT A719G,G460A.The relationships between different SNP with adverse reactions were compared.Results The mutauon rates of MTHFR C677T and A1298C were 66.33％ and 44.90％ respectively,which of TPMT A719G and G460A were 12.24％ and 9.18％ respectively.The proportion of MTHFR A1298AC developing thrombocytopenia was 28.13％,which was higher than 7.41％ of those carrying A1298AA and 8.33％ of those carrying A1298CC,the difference was statistically significant (P＜0.05).The proportion of MTHFR carrying A1298AA developing mucosal injury was 9.26 ％,which was lower than 43.75％ of those carrying A1298AC and 50.00％ of those A1298CC (P＜0.05).The differences in the genotypes of MTHFR C677T,TPMT A719G and TPMT G460A and the adverse reactions after chemotherapy were not statistically significant (P＞0.05).Conclusion The MTHFR A1298C polymorphism might be associated with the adverse reactions of MTX chemotherapy in ALL children.

Objective To investigate the clinical features and gene mutations of 3M syndrome. Method The clinical data of a child with 3M syndrome was retrospectively analyzed. The DNA was extracted from the peripheral blood of the child and parents, and the sequence analyses were performed by Agilent SureSelect exon capture and Illumina HiSeq sequencing platform. And the mutant gene was validated by Sanger sequencing. Results The six-month-old girl presented special face and growth retardation.The girl had a missense mutation c.4898C>T,p.T1633M in the CUL7 gene(NM_014780.4),and both her parents had heterozygous mutations.The girl was diagnosed with 3M syndrome.Conclusions The CUL7 mutation is the major causative gene of 3M syndrome in this girl. Early gene testing should be performed to confirm the diagnosis in suspected clinical phenotype.

Aromatic L-amino acid decarboxylase deficiency(AADCD) is a rare early-onset autosomal recessive genetic neurometabolic disease which can be treated with target therapy.To find, diagnose and treat at its early stage is important to improving the prognosis.The international neurotransmitter-related diseases working group (iNTD) developed the consensus guidelines for the diagnosis and treatment of AADCD in 2017, which provided reco-mmendations based on the consensus to facilitate the diagnosis, treatment and long-term management of patients.This article interpreted and summarized the clinical symptoms and treatment of AADCD according to the consensus, in order to raise pediatric clinicians′ awareness and treatment level of the disease.

In recent years, the management of respiratory diseases related to preterm birth has received extensive attention.In 2021, the American Thoracic Society brought together multidisciplinary experts in respiratory, neonato-logy, otolaryngology, sleep medicine, radiology and nursing specialties to develop Guidelines for outpatient respiratory management in infants, children, and adolescents with post-preterm respiratory disease (hereinafter referred to as the " Guideline" ), aiming to provide evidence-based medical evidence for standardized outpatient management of respiratory diseases associated with preterm birth at different ages.The Guideline was interpreted and summarized so that pediatric clinicians could correctly diagnose and treat these diseases, and understand and implement standardized outpatient management on the basis of evidence.

In recent years, the relationship between children′s chronic diseases and neuropsychiatric diseases and their pathogenesis have become a hot and difficult issue in pediatric research.Bronchial asthma (asthma) is a co-mmon chronic airway inflammatory disease in children.The latest large-scale population-based reports confirmed the close relationship between asthma and attention deficit hyperactivity disorder (ADHD), the most common neurodevelopmental disorder in children.Therefore, the specific relationship between asthma and ADHD, and the latest research progress of their risk factors were reviewed in this article in order to understand the specific relationship between them and its risk factors, so as to facilitate the long-term clinical management of asthmatic children.