孟鲁司特治疗呼吸道合胞病毒毛细支气管炎症状及反复喘息疗效研究

背景　呼吸道合胞病毒（RSV）毛细支气管炎易出现反复喘息，且下呼吸道分泌物中半胱氨酸白三烯（CysLTs）水平升高。而孟鲁司特是一种白三烯受体拮抗剂，关于其治疗RSV毛细支气管炎症状的研究相对较少。目的　探讨孟鲁司特改善婴幼儿RSV毛细支气管炎后症状及减轻反复喘息发作的有效性和安全性。方法　2015年6月-2017年6月连续纳入在潍坊市妇幼保健院出院的RSV毛细支气管炎患儿，随机分为治疗组、对照组。Ⅰ期，治疗组：口服孟鲁司特颗粒（4 mg）12周，1次/d；对照组：口服安慰剂12周，1次/d。对两组无症状天数、个人日记评分进行评估。随访9个月（Ⅱ期），观察Ⅰ+Ⅱ期反复喘息人数和医疗资源应用情况等。依据意向性分析（ITT）原则，应用全分析集（FAS）分析数据。结果　共纳入研究对象186例，治疗组92例，对照组94例。治疗组完成Ⅰ期研究的患儿为89例，对照组为90例；治疗组完成Ⅰ+Ⅱ期的患儿为84例，对照组为86例。治疗组平均依从性为97.8%（7 560/7 728），对照组平均依从性为97.4%（7 690/7 896），两组患儿平均依从性比较，差异无统计学意义（χ2=3.16，P=0.07）。在Ⅰ期研究期间，两组无症状天数、日间无症状天数、夜间无症状天数、个人日记评分比较，差异均无统计学意义（P>0.05）。在整个研究过程中（Ⅰ+Ⅱ期），治疗组RSV毛细支气管炎喘息复发人数少于对照组（P<0.05），治疗组喘息患儿出现2次及以上喘息比例低于对照组（χ2=5.14，P=0.02）。Ⅰ+Ⅱ期研究期间治疗组医疗资源应用人数、β-受体激动剂应用人数、糖皮质激素应用人数、住院人数低于对照组（P<0.05）。在事后亚组分析中，治疗组有湿疹史与父母哮喘史的患儿中无症状天数〔（49.7±20.2）、（51.3±20.9）d〕多于对照组〔（36.3±20.4）、（37.8±19.3）d〕（t=2.19，P=0.03；t=2.24，P=0.03）。整个研究过程中没有患儿因不良反应退出研究，两组间胃肠道紊乱、皮疹、转氨酶升高发生率比较，差异均无统计学意义（χ2=0.23，P=0.63；χ2=0.03，P=0.86；χ2=0.15，P=0.69）。结论　口服孟鲁司特（4 mg）12周不能改善RSV毛细支气管炎患儿呼吸道症状，但能降低患儿反复喘息发作次数。口服孟鲁司特（4 mg）有一定效果且安全。     

The respiratory syncytial virus fusion protein-specific B cell receptor repertoire reshaped by post-fusion subunit vaccination

Respiratory syncytial virus (RSV) is the major cause of acute lower respiratory illness in children of less than 5 years of age which usually results in hospitalization or even in death. Vaccine development is hampered in consequence of a failed vaccine trial with fatalities in the 1960s. Even though research has been more focused on the RSV fusion protein in its pre-fusion conformation, maternal vaccination with post-fusion protein (post F) was considered as a promising vaccine strategy for passive immunization of babies, because post F preserves very potent neutralizing epitopes. We extensively analyzed post F-binding B cell receptor (BCR) repertoires of three vaccinees who received a post F-subunit vaccine in the context of a first-in-human, Phase 1, randomized, observer-blind, placebo-controlled clinical trial (ClinicalTrials.gov Identifier: NCT02298179). In order to compare the vaccine-induced BCR repertoires with BCR repertoires induced by natural infection, we also analyzed pre F- and post F-binding BCRs isolated from a healthy blood donor with relatively high F-binding memory B cell (MBC) frequencies. Analysis of the vaccine-induced repertoires revealed that preferentially V_H4-encoded BCRs were expanded in response to vaccination. Estimation of antigen-driven selection further demonstrated that expanded BCRs accumulated positively selected replacement mutations which substantiated the hypothesis that post F-vaccination induces diversification of V_H4-encoded BCRs in germinal centers. Comparison of the vaccine-induced BCR repertoires with clonally related pre and post F-binding BCRs of the healthy blood donor suggested that the vaccine expanded pre/post F cross-reactive MBCs. Interestingly, several vaccine-induced BCRs shared stereotypic VDJ gene junctions with known neutralizing Abs. Once expressed for functional characterization, the selected monoclonal Abs demonstrated the predicted neutralization activities in plaque reduction neutralization assays indicating that the post F-vaccine induced expansion of neutralizing BCRs.     

Effectiveness of the 10-valent pneumococcal conjugate vaccine against radiographic pneumonia among children in rural Bangladesh: A case-control study

BackgroundPneumococcal conjugate vaccine (PCV) effectiveness against radiographic pneumonia in South Asia is unknown. Bangladesh introduced PCV10 in 2015 using a three dose primary series (3 + 0). We sought to measure PCV10 effectiveness for two or more vaccine doses on radiographic pneumonia among vaccine-eligible children in rural Bangladesh.MethodsWe conducted a matched case-control study over two years from 2015 to 2017 using clinic and community controls in three subdistricts of Sylhet, Bangladesh. Cases were vaccine eligible 3–35 month olds at Upazila Health Complex outpatient clinics with World Health Organization-defined radiographic primary endpoint pneumonia (radiographic pneumonia). Clinic controls were matched to cases within a one week time window by age, sex, and clinic and had an illness unlikely to be Streptococcus pneumoniae; community controls were healthy and similarly matched within a one week time window by age and sex, and distance from the clinic. We estimated adjusted vaccine effectiveness (aVE) using conditional logistic regression.ResultsWe matched 1262 cases with 2707 clinic and 2461 community controls. Overall, aVE using clinic controls was 21.4% (95% confidence interval, −0.2%, 38.4%) for ≥2 PCV10 doses and among 3–11 month olds was 47.3% (10.5%, 69.0%) for three doses. aVE increased with higher numbers of doses in clinic control sets (p = 0.007). In contrast, aVE using community controls was 7.6% (95% confidence interval, −22.2%, 30.0%) for ≥2 doses. We found vaccine introduction in the study area faster and less variable than expected with 75% coverage on average, which reduced power. Information bias may also have affected community controls.ConclusionsClinic control analyses show PCV10 prevented radiographic pneumonia in Bangladesh, especially among younger children receiving three doses. While both analyses were underpowered, community control enrollment – compared to clinic controls – was more difficult in a complex, pluralistic healthcare system. Future studies in comparable settings may consider alternative study designs.     

Recomendaciones sobre el manejo clínico de la infección por el «nuevo coronavirus» SARS-CoV2. Grupo de trabajo de la Asociación Española de Pediatría (AEP)

On 31 December 2019, the Wuhan Municipal Committee of Health and Healthcare (Hubei Province, China) reported that there were 27 cases of pneumonia of unknown origin with symptoms starting on the 8 December. There were 7 serious cases with common exposure in market with shellfish, fish, and live animals, in the city of Wuhan. On 7 January 2020, the Chinese authorities identified that the agent causing the outbreak was a new type of virus of the Coronaviridae family, temporarily called «new coronavirus», 2019-nCoV. On January 30th, 2020, the World Health Organisation (WHO) declared the outbreak an International Emergency. On 11 February 2020 the WHO assigned it the name of SARS-CoV2 and COVID-19 (SARS-CoV2 and COVID-19).The Ministry of Health summoned the Specialties Societies to prepare a clinical protocol for the management of COVID-19. The Spanish Paediatric Association appointed a Working Group of the Societies of Paediatric Infectious Diseases and Paediatric Intensive Care to prepare the present recommendations with the evidence available at the time of preparing them.     

电阻抗断层成像技术在儿科呼吸系统疾病诊治中的应用

电阻抗断层成像技术(electrical impedance tomography,EIT)作为一项新兴的功能性成像技术,具有无损伤、便携、图像监护等突出特点。肺功能成像是目前EIT最主要的应用领域,可以实现实时动态监测肺通气及血流灌注。本文对肺EIT在儿童呼吸系统疾病及其诊疗过程中的应用基础及临床研究进展进行总结,为未来EIT技术在儿科临床急救领域的推广应用提供帮助。     

Novel HLA-A2-restricted human metapneumovirus epitopes reduce viral titers in mice and are recognized by human T cells

Human metapneumovirus (HMPV) is a major cause of morbidity and mortality from acute lower respiratory tract illness, with most individuals seropositive by age five. Despite the presence of neutralizing antibodies, secondary infections are common and can be severe in young, elderly, and immunocompromised persons. Preclinical vaccine studies for HMPV have suggested a need for a balanced antibody and T cell immune response to enhance protection and avoid lung immunopathology. We infected transgenic mice expressing human HLA-A*0201 with HMPV and used ELISPOT to screen overlapping and predicted epitope peptides. We identified six novel HLA-A2 restricted CD8⁺ T cell (T_CD8) epitopes, with M_39–47 (M39) immunodominant. Tetramer staining detected M39-specific T_CD8 in lungs and spleen of HMPV-immune mice. Immunization with adjuvant-formulated M39 peptide reduced lung virus titers upon challenge. Finally, we show that T_CD8 from HLA-A*0201 positive humans recognize M39 by IFNγ ELISPOT and tetramer staining. These results will facilitate HMPV vaccine development and human studies.