Clinical features and FGFR3 mutations of children with achondroplasia / 中国当代儿科杂志

OBJECTIVES@#To study the clinical features and fibroblast growth factor receptor 3 (FGFR3) gene mutations of children with achondroplasia (ACH) through an analysis of 17 cases.@*METHODS@#A retrospective analysis was performed on the clinical data and FGFR3 gene detection results of 17 children with ACH who were diagnosed from January 2009 to October 2021.@*RESULTS@#Of the 17 children with ACH, common clinical manifestations included disproportionate short stature (100%, 17/17), macrocephaly (100%, 17/17), trident hand (82%, 14/17), and genu varum (88%, 15/17). The common imaging findings were rhizomelic shortening of the long bones (100%, 17/17) and narrowing of the lumbar intervertebral space (88%, 15/17). Major complications included skeletal dysplasia (100%, 17/17), middle ear dysfunction (82%, 14/17), motor/language developmental delay (88%, 15/17), chronic pain (59%, 10/17), sleep apnea (53%, 9/17), obesity (41%, 7/17), foramen magnum stenosis (35%, 6/17), and hydrocephalus (24%, 4/17). All 17 children (100%) had FGFR3 mutations, among whom 13 had c.1138G>A hotspot mutations of the FGFR3 gene, 2 had c.1138G>C mutations of the FGFR3 gene, and 2 had unreported mutations, with c.1252C>T mutations of the FGFR3 gene in one child and c.445+2_445+5delTAGG mutations of the FGFR3 gene in the other child.@*CONCLUSIONS@#This study identifies the unreported mutation sites of the FGFR3 gene, which extends the gene mutation spectrum of ACH. ACH is a progressive disease requiring lifelong management through multidisciplinary collaboration.

A predictive analysis of the association between clinical phenotypes and genotypes in children with Becker muscular dystrophy/Duchenne muscular dystrophy / 中国当代儿科杂志

OBJECTIVE@#To study the association between clinical phenotypes and genotypes in children with Becker muscular dystrophy (BMD)/Duchenne muscular dystrophy (DMD) so as to provide a theoretical basis for disease management, gene therapy, and prenatal diagnosis.@*METHODS@#A retrospective analysis was performed for the clinical data and gene detection results of 52 children with BMD/DMD. Multiplex ligation-dependent probe amplification (MLPA) was used to detect the DMD gene. The children with negative results of MLPA were further screened by exon chip capture combined with next-generation sequencing (NGS). The mothers of 20 probands were validated by sequencing.@*RESULTS@#The pathogenic genes for BMD/DMD were detected in 50 children by MLPA and NGS, with a detection rate of 96%. Among the 52 children, 36 (69%) had gene deletion, 7 (13%) had duplication, and 7 (13%) had micromutation. Among the 43 children with deletion/duplication, 32 had DMD and 11 had BMD; 37 children (86%) met the reading frame rule, among whom 27 (96%) had DMD and 10 (67%) had BMD. All 7 children with micromutation had DMD.@*CONCLUSIONS@#The reading frame rule has an extremely high predictive value for DMD but a limited predictive value for BMD.

Application of pulmonary function and fractional exhaled nitric oxide tests in the standardized management of bronchial asthma in children / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the changes of pulmonary function and fractional exhaled nitric oxide (FeNO) in the standardized treatment of bronchial asthma in children.</p><p><b>METHODS</b>A total of 254 children who were newly diagnosed with acute exacerbation of bronchial asthma were selected as asthma group, and they were divided into two subgroups: asthma with concurrent rhinitis and asthma without concurrent rhinitis. All patients received the standardized management and treatment for one year. The pulmonary function parameters included forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), maximal mid-expiratory flow (MMEF), and mid-expiratory flow at 25%, 50%, and 75% of vital capacity (MEF25, MEF50, and MEF75). The FeNO levels were measured before treatment and at 3, 6, 9, and 12 months after treatment. Another 62 healthy children were selected as the control group, and the pulmonary function and FeNO levels were measured only once.</p><p><b>RESULTS</b>During one year of standardized treatment, FEV1, PEF, MMEF, MEF25, MEF50, and MEF75 gradually increased, and FeNO levels gradually decreased (P<0.05). Indicators of large airway function, such as FEV1 and PEF, almost returned to normal after 6 months of treatment; indicators of small airway function, such as MMEF, MEF25, MEF50, and MEF75 almost returned to normal after 9 months of treatment; there were no significant differences in the above indices between the asthma group and the control group after one year of treatment (P>0.05). However, the asthma group had a significantly higher FeNO levels than the control group after one year of treatment (P<0.05). The asthmatic patients with concurrent rhinitis had significantly higher FeNO levels than those without concurrent rhinitis before treatment and 3 months after treatment (P<0.05). Before treatment, there was a significant negative correlation between FeNO levels and pulmonary function parameters (P<0.05).</p><p><b>CONCLUSIONS</b>With the standardized treatment of bronchial asthma in children, pulmonary function parameters gradually increase and FeNO levels gradually decrease. The recovery of large airway function occurs earlier than the recovery of small airway function. Furthermore, the effect of rhinitis on airway responsiveness should be noted.</p>