肺炎支原体（MP）是我国2023年儿童秋冬季呼吸道感染高峰的主要病原体，临床表现出感染低龄化、症状重、肺炎比例较高的特点，这与MP流行的周期性、我国耐大环内酯类MP比例高、新型冠状病毒感染后的免疫紊乱等因素有关。临床上需要加强对低龄儿童的防护，加强对重症病例的早期识别和治疗。.

Objective: To investigate and summarize pediatric patients with severe Mycoplasma pneumoniae pneumonia (MPP) presenting with varied clinical and chest imaging features in order to guide the individualized treatment. Methods: This was a retrospective cohort study. Medical records of clinical, imaging and laboratory data of 505 patients with MPP who were admitted to the Department Ⅱ of Respirology Center, Beijing Children\'s Hospital, Capital Medical University from January 2016 to October 2023 and met the enrollment criteria were included. They were divided into severe group and non-severe group according to whether lower airway obliterans was developed. The clinical and chest imaging features of the two groups were analyzed. Those severe cases with single lobe ≥2/3 consolidation (lobar consolidation) were further divided into subtype lung-necrosis and subtype non-lung-necrosis based on whether lung necrosis was developed. Comparison on the clinical manifestations, bronchoscopic findings, whole blood C-reactive protein (CRP) and other inflammatory indicators between the two subtypes was performed. Comparisons between two groups were achieved using independent-sample t-test, nonparametric test or chi-square test. Univariate receiver operating characteristic (ROC) curve analyses were performed on the indicators such as CRP of the two subtypes. Results: Of the 505 cases, 254 were male and 251 were female. The age of the onset was (8.2±2.9) years. There were 233 severe cases, among whom 206 were with lobar consolidation and 27 with diffuse bronchiolitis. The other 272 belonged to non-severe cases, with patchy, cloudy infiltrations or single lobe <2/3 uneven consolidation or localized bronchiolitis. Of the 206 cases (88.4%) severe cases with lobar consolidation, 88 harbored subtype lung-necrosis and 118 harbored subtype non-lung-necrosis. All 206 cases (100.0%) presented with persistent high fever, among whom 203 cases (98.5%) presented with inflammatory secretion obstruction and plastic bronchitis under bronchoscopy. Of those 88 cases with subtype lung-necrosis, there were 42 cases (47.7%) with dyspnea and 39 cases (44.3%) with moderate to massive amount of pleural effusion. There were 35 cases (39.8%) diagnosed with lung embolism during the disease course, of which other 34 cases (38.6%) were highly suspected. Extensive airway mucosal necrosis was observed in 46 cases (52.3%), and the level of their whole blood CRP was significantly higher than that of subtype non-lung-necrosis (131.5 (91.0, 180.0) vs. 25.5 (12.0, 43.1) mg/L, U=334.00, P<0.001). They were regarded as subtype \"lung consolidation-atelectasis-necrosis\". Of those 118 cases with subtype non-lung-necrosis, 27 cases (22.9%) presented with dyspnea and none were with moderate to massive amount of pleural effusion. Sixty-five cases (55.1%) presented with plastic bronchitis and localized airway mucosal necrosis was observed in 32 cases (27.1%). They were deemed as subtype \"lung consolidation-atelectasis\". ROC curve analyses revealed that whole blood CRP of 67.5 mg/L on the 6-10 th day of disease course exhibited a sensitivity of 0.96, a specificity of 0.89, and an area under the curve of 0.97 for distinguishing between these two subtypes among those with lobar consolidation. Conclusions: Pediatric patients with severe MPP present with lobar consolidation or diffuse bronchiolitis on chest imaging. Those with lobar consolidation harbor 2 subtypes as \"lung consolidation-atelectasis-necrosis\" and \"lung consolidation-atelectasis\". Whole blood CRP of 67.5 mg/L can be applied as an early discriminating indicator to discriminate between these two subtypes.
目的： 总结临床和影像学等不同表现的儿童重症肺炎支原体肺炎（MPP）的临床表型。 方法： 回顾性队列研究。纳入2016年1月至2023年10月在首都医科大学附属北京儿童医院呼吸中心临床部二病区住院的505例MPP患儿的临床、影像学和实验室数据等资料。根据是否遗留下气道闭塞分为重症和非重症组，分析组间的临床和影像学特征；根据重症组影像学表现为单个肺叶≥2/3的肺实变（大叶实变）的患儿是否发生肺组织坏死分为肺组织坏死亚型及肺组织未坏死亚型，比较两个亚型的临床表现、支气管镜下表现和全血C反应蛋白（CRP）等炎症指标。组间比较采用独立样本t检验、非参数检验或χ²检验。对两个亚型的CRP等炎症指标进行单因素受试者工作特征（ROC）曲线分析。 结果： 505例MPP患儿中，男254例、女251例，起病年龄（8.2±2.9）岁。重症组233例，其中影像学表现为大叶实变206例，弥漫性细支气管炎27例；非重症组272例，影像学表现均有斑片、云絮影或单个肺叶<2/3的不均匀实变或局限性细支气管炎。206例大叶实变患儿中，肺组织坏死亚型88例、肺组织未坏死亚型118例；持续高热206例（100.0%），支气管镜下存在炎性分泌物阻塞和塑形性支气管炎203例（98.5%）。88例肺组织坏死亚型中呼吸困难42例（47.7%），合并中-大量胸腔积液39例（44.3%），病程中明确合并肺栓塞35例（39.8%），另有34例（38.6%）高度可疑，支气管镜下可见气道较为广泛的黏膜坏死46例（52.3%）；肺组织坏死亚型的全血CRP水平高于肺组织未坏死亚型［131.5（91.0，180.0）比25.5（12.0，43.1）mg/L，U=334.00，P<0.001］，称为“肺实变-不张-坏死型”。118例肺组织未坏死亚型中呼吸困难27例（22.9%），中-大量胸腔积液0例，支气管镜下可见塑形性支气管炎65例（55.1%），可见气道黏膜少量坏死32例（27.1%），称为“肺实变-不张型”。ROC曲线分析示病程第6~10天的全血CRP 67.5 mg/L对于在大叶实变患儿中识别出“肺实变-不张-坏死型”的灵敏度0.96，特异度0.89，曲线下面积0.97。 结论： 儿童重型MPP的影像学表现为大叶实变或弥漫性细支气管炎，其中大叶实变可分为“肺实变-不张-坏死型”和“肺实变-不张型”两个亚型，病程第6~10天的全血CRP 67.5 mg/L可作为两个亚型的早期区分指标。.

Feral populations of aoudad (Ammotragus lervia) occur in Texas bighorn sheep (Ovis canadensis) habitat and pose several conceptual ecological threats to bighorn sheep re-establishment efforts. The potential threat of disease transmission from aoudad to bighorn sheep may exacerbate these issues, but the host competency of aoudad and subsequent pathophysiology and transmissibility of pneumonic pathogens involved in the bighorn sheep respiratory disease complex is largely unknown. Because the largest population-limiting diseases of bighorn sheep involve pathogens causing bronchopneumonia, we evaluated the host competency of aoudad for Mycoplasma ovipneumoniae and leukotoxigenic Pasteurellaceae. Specifically, we described the shedding dynamics, pathogen carriage, seroconversion, clinical patterns, and pathological effects of experimental infection among wild aoudad held in captivity. We found that aoudad are competent hosts capable of maintaining and intraspecifically transmitting Mycoplasma ovipneumoniae and Pasteurellaceae and can shed the bacteria for 53 days after exposure. Aoudad developed limited clinical signs and pathological findings ranged from mild chronic lymphohistiocytic bronchointerstitial pneumonia to severe and acute suppurative pneumonia, similarly, observed in bighorn sheep infected with Mycoplasma spp. and Pasteurellaceae bacteria, respectively. Furthermore, as expected, clinical signs and lesions were often more severe in aoudad inoculated with a combination of Mycoplasma ovipneumoniae and Pasteurellaceae as compared to aoudad inoculated with only Mycoplasma ovipneumoniae. There may be evidence of interindividual susceptibility, pathogenicity, and/or transmissibility, indicated by individual aoudad maintaining varying severities of chronic infection who may be carriers continuously shedding pathogens. This is the first study to date to demonstrate that aoudad are a conceptual disease transmission threat to sympatric bighorn sheep populations due to their host competency and intraspecific transmission capabilities.

BACKGROUND: An improper host immune response to Mycoplasma pneumoniae generates excessive inflammation, which leads to the impairment of pulmonary ventilation function (PVF). Azithromycin plus inhaled terbutaline has been used in the treatment of Mycoplasma pneumoniae pneumonia (MPP) in children with impaired pulmonary function, but previous randomized controlled trials (RCTs) showed inconsistent efficacy and safety. This study is aimed to firstly provide a systematic review of the combined therapy.
METHODS: This study was registered at the International Prospective Register of Systematic Reviews (PROSPERO CRD42023452139). A PRISMA-compliant systematic review and meta-analysis was performed. Six English and four Chinese databases were comprehensively searched up to June, 2023. RCTs of azithromycin sequential therapy plus inhaled terbutaline were selected. The revised Cochrane risk of bias tool for randomized trials (RoB2) was used to evaluate the methodological quality of all studies, and meta-analysis was performed using Stata 15.0 with planned subgroup and sensitivity analyses. Publication bias was evaluated by a funnel plot and the Harbord\' test. Certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation recommendations.
RESULTS: A total of 1,938 pediatric patients from 20 RCTs were eventually included. The results of meta-analysis showed that combined therapy was able to significantly increase total effectiveness rate (RR = 1.20, 95%CI 1.15 to 1.25), forced expiratory volume in one second (SMD = 1.14, 95%CIs, 0.98 to 1.29), the ratio of forced expiratory volume in one second/forced vital capacity (SMD = 2.16, 95%CIs, 1.46 to 2.86), peak expiratory flow (SMD = 1.17, 95%CIs, 0.91 to 1.43). The combined therapy was associated with a 23% increased risk of adverse reactions compared to azithromycin therapy alone, but no significant differences were found. Harbord regression showed no publication bias (P = 0.148). The overall quality of the evidence ranged from moderate to very low.
CONCLUSIONS: This first systematic review and meta-analysis suggested that azithromycin sequential therapy plus inhaled terbutaline was safe and beneficial for children with MPP. In addition, the combined therapy represented significant improvement of PVF. Due to lack of high-quality evidence, our results should be confirmed by adequately powered RCTs in the future.

Currently, there is a nationwide outbreak of Mycoplasma pneumoniae infections. M. pneumoniae is a bacterium that can cause atypical pneumonia, especially in children and young adults, and does not respond to the standard antibiotics prescribed for pneumonia. In addition, the bacterium regularly causes extra-pulmonary symptoms. In our hospitals, we have admitted 100 patients (including 20 children) with M. pneumoniae since the fall of 2023, many of which were young and had severe clinical symptoms. It is important to recognize the clinical picture to start effective antibiotic treatment. In this clinical lesson, we will provide two examples of recently admitted patients and discuss the characteristics of all inpatients who have presented to our hospitals during this epidemic. Finally, we pay attention to antibiotic policy and antibiotic resistance.

BACKGROUND: Mycoplasma pneumoniae pneumonia is a common respiratory infection among children. However, the occurrence of thromboembolism with plastic bronchitis in association with Mycoplasma pneumoniae pneumonia is extremely rare. This case series presents five cases of children with Mycoplasma pneumoniae pneumonia who developed thromboembolism and plastic bronchitis. The clinical presentation, diagnostic approach, and management strategies are discussed.
METHODS: A retrospective analysis was conducted on medical records from a pediatric hospital. Patient demographics, clinical features, laboratory findings, imaging results, treatment modalities, and outcomes were collected.
RESULTS: The patients in our case series presented with varying degrees of respiratory distress, cough, and fever. Imaging studies revealed evidence of thromboembolism based on pulmonary artery occlusion. Bronchial casts were observed by bronchoscopy. Laboratory tests demonstrated elevated D-dimer levels and fibrinogen degradation products. All patients received a combination of low molecular weight heparin anticoagulation and supportive care.
CONCLUSIONS: Thromboembolism with plastic bronchitis associated with Mycoplasma pneumoniae pneumonia is a rare but potentially serious complication in children. Prompt recognition and management are crucial for improving patient outcomes. This case series highlights the diverse clinical presentations, diagnostic challenges, and treatment strategies for this unique clinical entity. Further research is needed to better understand the pathogenesis and optimal management of this condition.

BACKGROUND: Budesonide, capable of reducing vascular permeability, suppressing mucus secretion, and alleviating edema and spasms, is widely used in China for combined infectious disease treatment. This study assesses budesonide\'s efficacy and safety as an adjunct to azithromycin in pediatric Mycoplasma pneumonia management in China, aiming to establish a strong theoretical foundation for its clinical application.
METHODS: We conducted a comprehensive search for qualifying studies across 5 English databases and 4 Chinese databases, covering publications until October 31, 2023. Endpoint analyses were performed using standard software (Stata Corporation, College Station, TX). This study was conducted in compliance with the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses.
RESULTS: A total of 24 randomized controlled trials were involved in the current study, including 2034 patients. Our findings indicate that the combination of budesonide with azithromycin for the treatment of pediatric Mycoplasma pneumonia delivers superior therapeutic efficacy (Intravenous: odds ratio [OR], 0.156, P < .001; Sequential: OR, 0.163, P = .001; Oral: OR, 0.139, P < .001), improved pulmonary function (Forced expiratory volume in 1 second: weighted mean differences [WMD], -0.28, P = .001; Peak expiratory flow: WMD, -0.554, P = .002; Forced vital capacity: WMD, -0.321, P < .001), diminished lung inflammation (IL-6: WMD, 4.760, P = .002; c-reactive protein: WMD, 5.520, P < .001; TNF-α: WMD, 9.124, P < .001), reduced duration of fever, faster resolution of cough and rales, all without increasing the occurrence of adverse events.
CONCLUSIONS: The combination of budesonide and azithromycin demonstrates enhanced therapeutic effectiveness, promotes improved pulmonary function, shortens the duration of symptoms, and effectively mitigates the overexpression of inflammatory factors like c-reactive protein, TNF-α, and IL-6, all without an associated increase in adverse reactions in pediatric mycoplasma pneumonia.

BACKGROUND: Nonpharmaceutical interventions (NPIs) implemented to reduce the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have suppressed the spread of other respiratory viruses during the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to explore the epidemiological trends and clinical characteristics of Mycoplasma pneumoniae (MP) infection among inpatient children with lower respiratory tract infection (LRTI) before and during the COVID-19 pandemic, and investigate the long-term effects of China\'s NPIs against COVID-19 on the epidemiology of MP among inpatient children with LRTI.
METHODS: Children hospitalised for LRTI at the Department of Pulmonology, The Children\'s Hospital, Zhejiang University School of Medicine (Hangzhou, China) between January 2019 and December 2022 were tested for common respiratory pathogens, including Mycoplasma pneumoniae (MP), Chlamydia trachomatis (CT) and other bacteria. Clinical data on age, sex, season of onset, disease spectrum, and combined infection in children with MP-induced LRTI in the past 4 years were collected and analysed.
RESULTS: Overall, 15909 patients were enrolled, and MP-positive cases were 1971 (34.0%), 73 (2.4%), 176 (5.8%), and 952 (20.6%) in 2019, 2020, 2021, and 2022, respectively, with a significant statistical difference in the MP-positive rate over the 4 years (p <0.001). The median age of these children was preschool age (3-6 years), except for 2022, when they were school age (7-12 years), with statistical differences. Comparing the positive rates of different age groups, the school-age children (7-12 years) had the highest positive rate, followed by the preschoolers (3-6 years) in each of the 4 years. Compared among different seasons, the positive rate of MP in children with LRTI was higher in summer and autumn, whereas in 2020, it was highest in spring. The monthly positive rate peaked in July 2019, remained low from 2020 to 2021, and rebounded until 2022. Regarding the disease spectrum, severe pneumonia accounted for the highest proportion (46.3%) pre-pandemic and lowest (0%) in 2020.
CONCLUSIONS: Trends in MP detection in children with LRTIs suggest a possible correlation between COVID-19 NPIs and significantly reduced detection rates. The positivity rate of MP gradually rose after 2 years. The epidemic season showed some differences, but school-age children were more susceptible to MP before and during the COVID-19 pandemic.

BACKGROUND: Neurospecific Enolase (NSE), a multifunctional protein, is present in various tissues of the body and plays an important role in many disease processes, such as infection, inflammation, tumours, injury, and immunity. In recent years, the application of NSE in respiratory diseases has become increasingly widespread and a research hotspot.
OBJECTIVE: This study aims to explore the relationship between NSE and childhood pneumonia, providing assistance for the diagnosis and assessment of pneumonia.
METHODS: Using prospective research and case-control methods, We selected 129 children with pneumonia hospitalised in Weifang People\'s Hospital from September 2020 to April 2022 as the case group. Among them were 67 cases of Mycoplasma pneumoniae pneumonia (MP+), 62 cases of non-Mycoplasma pneumoniae pneumonia (MP -), and 21 cases of severe pneumonia. At the same time, 136 children who underwent outpatient health examinations were selected as the control group. The levels of NSE, ESR, CRP in cases group and NSE in control group were measured separately.
RESULTS: The NSE levels in the MP + group were 17.86 (14.29-22.54) ng/mL, while those in the MP- group were 17.89 (14.10-21.66) ng/mL, both of which were higher than the control group\'s NSE levels of 13.26(12.18,14.44) ng/mL (H = 46.92, P = 0.000). There was no statistically significant difference in NSE levels between the MP + and MP - groups (P > 0.05). The NSE level in the severe pneumonia group was 27.38 (13.95-34.06) ng/mL, higher than that in the mild pneumonia group, which was 17.68 (14.27-21.04) ng/mL, (P = 0.024). The AUC values for diagnosing pneumonia are NSE0.714, CRP0.539, and ESR0.535, with NSE having the highest diagnostic value.
CONCLUSIONS: Serum NSE can serve as an inflammatory indicator for paediatric pneumonia, which has important clinical guidance significance for the diagnosis, condition evaluation, and prognosis of paediatric pneumonia.

We report a large-scale outbreak of Mycoplasma pneumoniae respiratory infections encompassing 218 cases (0.8% of 26,449 patients tested) during 2023-2024 in Marseille, France. The bacterium is currently circulating and primarily affects children <15 years of age. High prevalence of co-infections warrants the use of a syndromic diagnostic strategy.