Objective:To explore the relationship between the type of mutation and clinical features, prognosis, and clinical characteristics of chronic granulomatous disease (CGD) caused by compound heterozygous mutations in the NCF2 gene in children. Methods:The clinical data of 1 case of neonatal CGD caused by compound heterozygous mutations of NCF2 gene at Tianjin Children′s Hospital in August 2019 was analyzed, and domestic and international literatures were searched to summarize the clinical characteristics, gene mutation type and prognosis of CGD caused by NCF2 mutation. Results:The diagnosis of CGD was confirmed by the presence of compound heterozygous mutations c. 196_197insA (p.Arg66Glnfs23X) and c. 1180T>G (p.Tyr394Asp) in the NCF2 gene, accompanied with the clinical manifestations of fever, cough, multiple clumps and nodules in the chest CT at 25 days after birth, and the neutrophil respiratory burst test stimulation index(SI) 23.This new mutation was not reported in the Human Genetic Mutation Database.The child had a residual portion of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity and was followed up until the age of 9 months with an antifungal drug without recurrent infection.A total of 101 cases of CGD patients with NCF2 gene mutation were reported in domestic and international databases.Totally, 33 cases had SI results, with 22 cases below 3, 11 cases above 3, and 8 cases of missense mutations. Conclusions:c. 196_197insA and c. 1180T>G are new mutations in NCF2 gene that can lead to CGD.CGD patients containing missense mutations in the NCF2 gene may have more residual NADPH oxidase activity.

Objective To investigate the distribution, clinical diagnosis and treatment methods of the extrapulmo-nary complications in children with mycoplasma pneumoniae (MP). Methods The clinical data of 1 100 patients confirmed the diagnosis of mycoplasma pneumonia and with the positive serum MP-IgM test were collected in this study. The distribu-tion and clinical characteristics and MP-DNA detection rates were compared between 417 patients with extrapulmonary com-plications and 683 cases without complications. The occurrence of various complications in a four-year period was analyzed. Clinical data were compared between fiberoptic bronchoscopy lavage group and non-surgical group. Results The MP-DNA detection rate and the length of hospital stay were higher in patients with pulmonary complications than those of patients without complications. The most common types of extrapulmonary complications were liver damage, skin rashes and gastrointestinal reactions , but less severe. Encephalitis, nephritis and myocarditis were rare complications, but severe and occult. The fatal hemophagocytic lymphohistiocytosis (HLH) was also visible in patients. Bronchoscopy lavage was conducive to the recovery of the disease. Conclusion MP pneumonia showed high incidence and risks of extrapulmonary complica-tions, which required careful clinical observation and inspection, the dynamic monitoring laboratory markers and comprehen-sive treatment as well.

The clinical data of 2 children with refractory Mycoplasma pneumoniae pneumonia complicated with intracardiac thrombosis and pulmonary embolism, treated in Tianjin Children′s Hospital from July 2019 to January 2020, were analyzed retrospectively.One patient was an 8-year-old girl, who was admitted to the hospital mainly because of " fever for 5 days and cough for 2 days" . The other patient was a 7-year-old boy, who was admitted due to " intermittent fever with cough for 24 days and chest pain for 1 day" . Both children were complicated with elevated D-dimer levels and positive antiphospholipid antibody.During the treatment, right cardiac thrombosis and pulmonary embolism occurred in both cases, and the manifestations of thrombosis related symptoms were not typical.After the patients received anticoagulation treatment and thrombolytic therapy with urokinase, the cardiac thrombus dissipated and the pulmonary embolism improved.For refractory Mycoplasma pneumoniae pneumonia complicated with intracardiac thrombosis and pulmonary embolism, thrombolytic therapy can be applied to some children in addition to anticoagulant therapy.

Hypersensitivity pneumonitis (HP) is an immune-mediated interstitial lung disease (ILD). It is a disease with highly heterogeneous clinical manifestations, severity and outcomes, which are associated with individual sensitivity, as well as property, dosage, duration and frequency of exposure to the antigens.The 2020 adult HP guideline reclassifies it and describes its radiographic features in detail.HP often occurs in adults, also affects the pediatric population and is one of the most common ILDs in children.The most common factors causing HP in children are avian and fungal antigens in the home environment.The diagnosis of HP is based on clear antigens, typical symptoms and characteristic radiological manifestations.The serum-specific IgG antibody, bronchoalveolar lavage fluid, and pulmonary function tests can help diagnose HP clearly, and lung histopathology is required for children whose diagnosis cannot be confirmed.Early diagnosis and adequate avoidance of antigen exposure are the keys to its treatment and prognosis.