Objective:To observe the efficacy and safety of combined lienal polypeptide injection therapy in the treatment of Mycoplasma pneumoniae pneumonia（MPP）in children aged 3 to 14 years old in multiple clinical centers.Methods:A randomized，controlled，multi-center clinical study design was adopted.A total of 240 hospitalized children aged 3 to 14 years old with MPP from 7 hospitals from September 1，2023 to January 31，2024 were included.According to the severity of pneumonia，they were divided into the mild MPP group with 80 cases and the severe MPP/refractory MPP（SMPP/RMPP）group with 160 cases，and then randomly divided into the control group and the experimental group at a ratio of 1 ∶1，using the random number table method.After screening，subjects entered a treatment period of 5 to 7 days.The control group was treated with azithromycin，while the experimental group was treated with azithromycin plus lienal polypeptide injection .The recovery of lung CT，length of hospital stay，duration of fever，cough score，whether mild cases developed into severe or refractory cases，duration of hormone use，use of intravenous immunoglobulin（IVIG），bronchoscopy treatment，and immune function were observed between the two groups to evaluate the efficacy of lienal polypeptide injection.Adverse events after medication，vital signs，blood routine，urine routine，liver function，myocardial enzymes，renal function，and electrocardiogram were observed to evaluate the safety. Results:A total of 231 subjects have completed the trial in the 7 hospitals，including 118 cases in the experimental group and 113 cases in the control group.Main observation index：the rate of lung CT aggravation in the experimental group was lower than that in the control group（2.6% vs 15.3%， P<0.01），and the difference was statistically significant.Secondary indexes：there were no statistically significant differences in the length of hospital stay，duration of fever，cough score，duration of hormone use，whether IVIG treatment was used，the number of bronchoscopy treatment cases，and immunoglobulin between the two groups（all P>0.05）.However，the rate of cases of plastic bronchitis（PB）found under bronchoscopy in the experimental group was lower than that in the control group（0 vs 18.8%， P=0.03），and the difference was statistically significant.Among the mild MPP（72 cases），there were no statistically significant differences in the length of hospital stay，duration of fever，cough score，duration of hormone use，whether IVIG treatment was used，the number of bronchoscopy treatment cases，and the improvement rate of lung CT between the two groups（all P>0.05）.However，compared with the control group，the rate of cases developing into SMPP/RMPP in the experimental group was less（24.3% vs 48.6%， P=0.03），and the difference in IgG before and after treatment was small［0.53（-0.04，1.18）g/L vs 1.33（0.48，2.25）g/L， P=0.01］.Among the SMPP/RMPP cases（159 cases），the rate of cases of PB found under bronchoscopy in the experimental group was less than that in the control group（0 vs 20%， P=0.04），and the rate of cases with aggravated lung CT in the experimental group was less than that in the control group（1.3% vs 19.5%， P<0.01），and the improvement rate of lung CT in the experimental group was higher than that in the control group（88.8% vs 75.3%， P=0.03），with statistically significant differences.There were no statistically significant differences in the length of hospital stay，duration of fever，cough score，duration of hormone use，whether IVIG treatment was used，the number of bronchoscopy treatment cases，and immunoglobulin between the two groups（all P>0.05）.Two cases in the experimental group developed rashes，which improved after the drug was discontinued.There were no serious adverse reactions such as abnormal vital signs like dyspnea and cyanosis due to the use of lienal polypeptide injection.There were no obvious changes in blood routine，liver function，myocardial enzymes，renal function，electrocardiogram，and urine routine values before and after medication compared with the baseline. Conclusion:The combined use of lienal polypeptide injection in the treatment of MPP in children can reduce the probability of the transformation from mild cases to SMPP/RMPP，reduce the rate of aggravation of the image findings，promote the absorption of lung inflammation，reduce the rate of PB found under bronchoscopy，and has good safety.

Objective This retrospective study was based on 1 415 cases that had been done the flex-ible bronchoscopy examination.The data were analysed to investigate the value of flexible bronchoscope in the children's respiratory system diseases diagnosis,treatment and etiological study.Methods A total of 1 415 cases who admitted from June 2012 to December 2013 were included in the study and they were all met the inclusion criteria,had complete clinical data,done bronchoscope examinations,abnormal in the broncho-scope and diagnosed definitely.The endoscopic manifestation,clinical symptoms,X-ray film,laboratory data were analysed.Results In 1 415 cases,55.4% were boy,and 55.5% were younger than 5 years.Two cases (0.14%)were laryngeal cartilage soften,one case(0.07%)was epiglottic cyst,3 cases(0.21 %)were tra-cheomalacia,25 cases(1.8%)were bronchial foreign bodies,20 cases(1.4%)were tracheal bronchus de-formity,8 cases(5.7%)were tracheal stenosis,two cases(0.14%)were bronchial bridge,5 cases(0.35%) were bronchiolitis obliterans,6 cases (0.42%)were bronchiectasis,one case(0.07%)was immotile cilia syndrome,10 cases (0.71%)were bronchial tuberculosis,one case (0.07%)was aspergillosis,one case (0.07%)was pulmonary hemosiderosis,2 cases (0.14%)were pulmonary arteriovenous fistula,9 cases (0.63%)were plastic bronchitis,1 316 cases(93%)were founded tracheal intima inflammation,including the 350 cases(24.7%)of edema,mucosal folds form,279 cases(19.7%)of mucus plug obstruction,176 cases(12.4%)of suppurative obstruction,355 cases(25.1 %)of tracheal mucosal erosion necrosis,156 ca-ses(1 1.1 %)of wall fibrosis,stenosis,occlusion.Mycoplasma pneumoniae was the most common pathogen dectected in alveolar lavage.We also found that mycoplasma pneumonia easily combined the infection of bac-teria.A total of 1 19(22.7%)cases were no pathogens detected.In 1 415 cases,the main adverse reaction in the operations was hypoxemia caused by airway obstruction.Conclusion Flexible bronchoscopy examination is a very safe and reliable operation in diagnosis and treatment of respiratory diseases in pediat-rics,and plays an important role in the diagnosis of congenital developmental airway diseases,detection of pneumonia patho-gens and the treatment of lobe pneumonia.

Objective To investigate the advantages of pediatric electronic fiber bronchoscope ( FBO) in the infant bronchial foreign body,discuss the clinical features of infant bronchial foreign body,lung imaging characteristics and the kinds of microscopically position,the change of airway mucosa after stimulation by for-eign body under local anesthesia in 30 cases of infant bronchial foreign body. Methods Thirty cases,aged 0 to 3 years,were collected from September to December,2014. All of them were with foreign bodies examined by FBO in pediatric bronchoscopy room in Shengjing Hospital of China Medical University. Results In all infants, 6 cases (20. 0%) without history of inhaled foreign bodies and 24 cases (80. 0%) with a record history of in-haled. In the aspects of signs:normal breath sounds with a history of no choking cough in children were 2 cases (6. 7%) ,wheezing sounds were 3 patients (10. 0%) and weakened side breath sound was 1 case (3. 3%);with a history of choking cough in children,6 cases(20. 0%) with normal breath sounds,12 cases(40. 0%) with wheez-ing,6 cases(20. 0%) with lateral breath sounds less. Lung imaging characteristics was lack of specific perform-ance:only a case of all(n=30)show foreign body directly. Otherwise,other 29 cases had no specificity. Lung em-physema in 13 cases (43. 3%) is the main characteristic,while normal imaging findings in 2 cases (6. 7%). For-eign bodies in 19 cases were in the left lung (63. 4%) and 21 cases(70. 0%) of foreign body stimulated granula-tion inside airway,necrosis sputum bolt in distal obstruction of airway occured in 5 cases (16. 7%). Inhalled time of foreign body in airway was 4. 5 [2. 8,12. 5] day and inhalled time of foreign body in airway correlation coefficient with granulation hyperplasia(r=0. 688,P=0. 000),there was a significant correlation. Main adverse reaction was low oxygen in 6 cases (16. 7%). Conclusion The diagnostic accuracy of FBO under local anesthesia on children is high-er than other methods,and the FBO bronchial foreign bodies under local anesthesia is a safe and effective method.