Nirsevimab and Hospitalization for RSV Bronchiolitis.

BACKGROUND: Respiratory syncytial virus (RSV) is the leading cause of bronchiolitis, resulting in 3 million hospitalizations each year worldwide. Nirsevimab is a monoclonal antibody against RSV that has an extended half-life. Its postlicensure real-world effectiveness against RSV-associated bronchiolitis is unclear. METHODS: We conducted a prospective, multicenter, matched case-control study to analyze the effectiveness of nirsevimab therapy against hospitalization for RSV-associated bronchiolitis in infants younger than 12 months of age. Case patients were infants younger than 12 months of age who were hospitalized for RSV-associated bronchiolitis between October 15 and December 10, 2023. Control patients were infants with clinical visits to the same hospitals for conditions unrelated to RSV infection. Case patients were matched to control patients in a 2:1 ratio on the basis of age, date of hospital visit, and study center. We calculated the effectiveness of nirsevimab therapy against hospitalization for RSV-associated bronchiolitis (primary outcome) by means of a multivariate conditional logistic-regression model with adjustment for confounders. Several sensitivity analyses were performed. RESULTS: The study included 1035 infants, of whom 690 were case patients (median age, 3.1 months; interquartile range, 1.8 to 5.3) and 345 were matched control patients (median age, 3.4 months; interquartile range, 1.6 to 5.6). Overall, 60 case patients (8.7%) and 97 control patients (28.1%) had received nirsevimab previously. The estimated adjusted effectiveness of nirsevimab therapy against hospitalization for RSV-associated bronchiolitis was 83.0% (95% confidence interval [CI], 73.4 to 89.2). Sensitivity analyses gave results similar to those of the primary analysis. The effectiveness of nirsevimab therapy against RSV-associated bronchiolitis resulting in critical care was 69.6% (95% CI, 42.9 to 83.8) (27 of 193 case patients [14.0%] vs. 47 of 146 matched control patients [32.2%]) and against RSV-associated bronchiolitis resulting in ventilatory support was 67.2% (95% CI, 38.6 to 82.5) (27 of 189 case patients [14.3%] vs. 46 of 151 matched control patients [30.5%]). CONCLUSIONS: In a real-world setting, nirsevimab therapy was effective in reducing the risk of hospitalized RSV-associated bronchiolitis. (Funded by the National Agency for AIDS Research-Emerging Infectious Disease and others; ENVIE ClinicalTrials.gov number, NCT06030505.).

Epidemiology of childhood interstitial lung disease in France: the RespiRare cohort.

INTRODUCTION: Interstitial lung disease in children (chILD) are rare and mostly severe lung diseases. Very few epidemiological data are available in limited series of patients. The aim of this study was to assess the prevalence and incidence of chILD in France. METHODS: We performed within the RespiRare network a multicentre retrospective observational study in patients with chILD from 2000 to 2022 and a prospective evaluation of chILD's incidence between February 2022 and 2023. RESULTS: chILD was reported in 790 patients in 42 centres. The estimated 2022 prevalence in France was 44 /million children (95% CI 40.76 to 47.46) and the computed incidence was 4.4 /million children (95% CI 3.44 to 5.56). The median age at diagnosis was 3 months with 16.9% of familial forms. Lung biopsy and genetic analyses were performed in 23.4% and 76.9%, respectively. The most frequent chILD aetiologies in the <2 years group were surfactant metabolism disorders (16.3%) and neuroendocrine cell hyperplasia of infancy (11.8%), and in the 2-18 years group diffuse alveolar haemorrhage (12.2%), connective tissue diseases (11.4%), hypersensitivity pneumonitis (8.8%) and sarcoidosis (8.8%). The management included mainly oxygen therapy (52%), corticosteroid pulses (56%), oral corticosteroids (44%), azithromycin (27.2%), enteral nutrition (26.9%), immunosuppressants (20.3%) and hydroxychloroquine (15.9%). The 5-year survival rate was 57.3% for the patients diagnosed before 2 years and 86% between 2 and 18 years. CONCLUSION: This large and systematic epidemiological study confirms a higher incidence and prevalence of chILD than previously described. In order to develop international studies, efforts are still needed to optimise the case collection and to harmonise diagnostic and management practices.

Bronchiolitis: Increased severity in the post-COVID-19 era.

INTRODUCTION: Acute bronchiolitis is a pressing public health concern, leading to numerous infant hospitalizations worldwide annually. The notable decrease in bronchiolitis hospitalizations during the COVID-19 pandemic sparked concerns about a potential resurgence post-pandemic. Questions also arose about the severity of post-pandemic cases compared to prepandemic ones. This study aimed to compare bronchiolitis severity before and after the COVID-19 pandemic, alongside changes in the epidemiology of bronchiolitis viral agents. MATERIAL AND METHODS: We conducted a retrospective analysis of medical records concerning infants under 12 months hospitalized for acute bronchiolitis in our pediatric pulmonology department over a period of 5 years: 2 pre-COVID years (2018-2020), the COVID year (2020), and 2 post-COVID years (2021-2023). Clinical and laboratory data were collected using standardized forms. RESULTS: Hospital admissions exhibited comparable rates pre- and post-COVID but witnessed a decline during the COVID period. Post-COVID, bronchiolitis severity increased, with longer hospitalization durations (p < 0.001) and increased oxygen therapy (p = 0.04), coinciding with a surge in the prevalence of RSV infections (p = 0.01). Patients testing positive for RSV were significantly younger (p = 0.005) and exhibited more severe symptoms. DISCUSSION AND CONCLUSION: This study reveals a significant increase in bronchiolitis severity and a rise in RSV cases following the COVID pandemic. The implementation of preventive measures such as nirsevimab is crucial to alleviate the burden of respiratory illnesses in vulnerable populations. Continued vigilance and research are needed to address the evolving challenges of bronchiolitis in the post-COVID era.

Multicentric investigations of the role in the disease severity of accelerated phospholipid changes in COVID-19 patient airway.

CONTEXT: The changes in host membrane phospholipids are crucial in airway infection pathogenesis. Phospholipase A2 hydrolyzes host cell membranes, producing lyso-phospholipids and free fatty acids, including arachidonic acid (AA), which contributes significantly to lung inflammation. AIM: Follow these changes and their evolution from day 1, day 3 to day 7 in airway aspirates of 89 patients with COVID-19-associated acute respiratory distress syndrome and examine whether they correlate with the severity of the disease. The patients were recruited in three French intensive care units. The analysis was conducted from admission to the intensive care unit until the end of the first week of mechanical ventilation. RESULTS: In the airway aspirates, we found significant increases in the levels of host cell phospholipids, including phosphatidyl-serine and phosphatidyl-ethanolamine, and their corresponding lyso-phospholipids. This was accompanied by increased levels of AA and its inflammatory metabolite prostaglandin E2 (PGE2). Additionally, enhanced levels of ceramides, sphingomyelin, and free cholesterol were observed in these aspirates. These lipids are known to be involved in cell death and/or apoptosis, whereas free cholesterol plays a role in virus entry and replication in host cells. However, there were no significant changes in the levels of dipalmitoyl-phosphatidylcholine, the major surfactant phospholipid. A correlation analysis revealed an association between mortality risk and levels of AA and PGE2, as well as host cell phospholipids. CONCLUSION: Our findings indicate a correlation between heightened cellular phospholipid modifications and variations in AA and PGE2 with the severity of the disease in patients. Nevertheless, there is no indication of surfactant alteration in the initial phases of the illness.

Septin-dependent defense mechanisms against Pseudomonas aeruginosa are stalled in cystic fibrosis bronchial epithelial cells.

Airway epithelial cells form a physical barrier against inhaled pathogens and coordinate innate immune responses in the lungs. Bronchial cells in people with cystic fibrosis (pwCF) are colonized by Pseudomonas aeruginosa because of the accumulation of mucus in the lower airways and an altered immune response. This leads to chronic inflammation, lung tissue damage, and accelerated decline in lung function. Thus, identifying the molecular factors involved in the host response in the airways is crucial for developing new therapeutic strategies. The septin (SEPT) cytoskeleton is involved in tissue barrier integrity and anti-infective responses. SEPT7 is critical for maintaining SEPT complexes and for sensing pathogenic microbes. In the lungs, SEPT7 may be involved in the epithelial barrier resistance to infection; however, its role in cystic fibrosis (CF) P. aeruginosa infection is unknown. This study aimed to investigate the role of SEPT7 in controlling P. aeruginosa infection in bronchial epithelial cells, particularly in CF. The study findings showed that SEPT7 encages P. aeruginosa in bronchial epithelial cells and its inhibition downregulates the expression of other SEPTs. In addition, P. aeruginosa does not regulate SEPT7 expression. Finally, we found that inhibiting SEPT7 expression in bronchial epithelial cells (BEAS-2B 16HBE14o- and primary cells) resulted in higher levels of internalized P. aeruginosa and decreased IL-6 production during infection, suggesting a crucial role of SEPT7 in the host response against this bacterium. However, these effects were not observed in the CF cells (16HBE14o-/F508del and primary cells) which may explain the persistence of infection in pwCF. The study findings suggest the modification of SEPT7 expression as a potential approach for the anti-infective control of P. aeruginosa, particularly in CF.

Disseminated tuberculosis in a migrant child.

Tuberculosis (TB) poses a major global health threat, substantially affecting children, who contribute notably to new cases and deaths. Diagnosing TB in kids is challenging due to collection issues and the paucibacillary nature of the disease. Disseminated TB, uncommon in children in low TB incidence countries, remains a significant cause of morbidity in migrant populations. We illustrate a rare case of disseminated TB in a middle-childhood boy who migrated from Angola to France, displaying chronic cough, fatigue, weight loss and persistent fever. Investigations revealed widespread TB affecting several organs (lungs, heart, bones and lymph nodes). Prompt diagnosis led to a treatment regimen of four antibiotics (isoniazid, rifampin, pyrazinamide, ethambutol) and corticosteroids, resulting in substantial improvement after 2 months. Subsequent treatment involved two antibiotics (isoniazid and rifampin) for 10 more months. This case underscores the criticality of early identification and comprehensive treatment for disseminated TB, ensuring improved outcomes and reduced risks.

Pulmonary mucoepidermoid carcinoma in a 7-year-old child.

A 7-year-old boy presented with exertional dyspnea and cough, initially misdiagnosed as asthma. Imaging revealed a mass obstructing the left main bronchus, later identified as a pulmonary mucoepidermoid carcinoma (MEC). Following surgical sleeve resection, complete tumor removal occurred without malignancy in surrounding lymph nodes, resulting in symptom resolution without additional therapy. Pulmonary MEC, uncommon in pediatric patients, poses diagnostic challenges due to nonspecific symptoms, resulting in delayed diagnosis. Typically managed via complete surgical resection, MEC offers a favorable prognosis, primarily affecting central airways and requiring conservative surgical approaches to preserve lung tissue. This case underscores the diagnostic challenges of primary pulmonary MEC in pediatric patients. It stresses the need to consider unusual causes in pediatric respiratory symptoms and highlights the critical role of precise diagnostic methods and personalized surgical strategies in managing such rare pulmonary malignancies for optimal outcomes.

Lung biopsies in infants and children in critical care situation.

INTRODUCTION: Lung biopsy is considered as the last step investigation for diagnosing lung diseases; however, its indication must be carefully balanced with its invasiveness. The present study aims to evaluate the diagnostic yield of lung biopsy in critically ill patients hospitalized in the pediatric intensive care unit (ICU). MATERIAL AND METHODS: Children who underwent a lung biopsy in the ICU between 1995 and 2022 were included. Biopsies performed in the operating room and post-mortem biopsies were excluded. RESULTS: Thirty-one patients were included, with a median age of 18 days (2 days to 10.8 years); 21 (67.7%) were newborns. All patients required invasive mechanical ventilation, 26 (89.7%) had a pulmonary hypertension, and 22 (70.9%) were placed under extracorporeal membrane oxygenation (ECMO). The lung biopsy led to a diagnosis in 81% of the patients. The diagnostic reliability seemed to decrease with age (95% in newborns, 71% in 1 month to 2 years and 0/3 patients aged over 2 years old). Diffuse developmental disorders of the lung accounted for 15 (49%) patients, primarily alveolar capillary dysplasia, followed by surfactant disorders in 5 (16%) patients. Complications occurred in 9/31 (29%) patients including eight under ECMO, with massive hemorrhages in seven cases. DISCUSSION AND CONCLUSION: In critical situations, lung biopsy should be performed. Lung biopsy is a reliable diagnostic procedure for neonates in critical situation when a diffuse developmental disorder of the lung is suspected. The majority of lung biopsy complication was associated with the use of ECMO. The prospective evaluation of the complications of such procedure under ECMO, and particularly over 10 days of ECMO and in children over 2-year-old remains to be ascertained.

The significance of multidisciplinary team meetings in diagnosing and managing childhood interstitial lung disease within the RespiRare network.

INTRODUCTION: Childhood Interstitial Lung Disease (chILD) represents a rare and severe group of diseases for which the etiologic workup, classification, and management remain a challenge for most pediatric pulmonologists. In France in 2018, the RespiRare network established the first multidisciplinary team meetings (MDTm) dedicated to chILD. This study aims to investigate the impact of MDTm in chILD diagnosis and management as well as user satisfaction. METHODS: The MDTm took place on a monthly basis through video conferences. The participants consisted of a quorum and included pediatric pulmonologists, radiologists, geneticists, and pulmonologists, with an average of 10.5 participants per meeting. Patients provided consent to participate in MDTm and for data collection. Data were retrospectively extracted from MDTm reports. To evaluate the usefulness of the MDTm and the satisfaction of the participants, a survey was sent by email at least 3 months after the MDTm to the participants. RESULTS: A total of 216 chILD cases were discussed during 56 MDTm sessions. The median age of onset was 0.5 years (interquartile range 0-7). The MDTm sessions resulted in the correction of chILD etiology in 25% of cases (neuroendocrine cell hyperplasia of infancy 17%, surfactant metabolism disorder 8%, pulmonary alveolar proteinosis 4%, hemosiderosis 3%, sarcoidosis 3%, and others 34%), and chILD was ruled out in 7% of cases. A change in therapy was proposed for 46% of cases. User satisfaction was significant, particularly regarding their confidence in managing these rare diseases. DISCUSSION AND CONCLUSION: Dedicated MDTm sessions offer a unique opportunity to enhance chILD etiologic diagnosis and management, leading to increased physician knowledge and confidence in managing these patients.

Airway infections as a risk factor for Pseudomonas aeruginosa acquisition and chronic colonisation in children with cystic fibrosis.

BACKGROUND: Pseudomonas aeruginosa (Pa) infection is detrimental to people with cystic fibrosis (pwCF). Several clinical and genetic factors predispose to early Pa infections. However, the role of earlier infections with other pathogens on the risk of Pa infection in paediatric pwCF remains unknown. METHODS: Using Kaplan-Meier method, we computed the cumulative incidences of bacterial and fungal initial acquisition (IA) and chronic colonisation (CC) in 1,231 French pwCF under 18 years of age for methicillin-susceptible and resistant Staphylococcus aureus (MSSA and MRSA), Stenotrophomonas maltophilia, Haemophilus influenzae, Achromobacter xylosoxidans, and Aspergillus species. Previous infections were analysed as Pa-IA and Pa-CC risk factors using Cox regression models. RESULTS: By 2 years of age, 65.5% pwCF had experienced at least one bacterial or fungal IA, and 27.9% had experienced at least one CC. The median age of Pa-IA was 5.1 years, and Pa-CC was present in 25% pwCF by 14.7 years. While 50% acquired MSSA at 2.1 years, 50% progressed to chronic MSSA colonisation at 8.4 years. At 7.9 and 9.7 years, 25% pwCF were infected by S. maltophilia and Aspergillus spp., respectively. The risk of Pa-IA and Pa-CC increased with IAs of all other species, with hazard ratios (HR) up to 2.19 (95% Confidence interval (CI) 1.18-4.07). The risk of Pa-IA increased with the number of previous bacterial/fungal IAs (HR=1.89, 95% CI 1.57-2.28), with a 16% increase per additional pathogen; same trend was noted for Pa-CC. CONCLUSIONS: This study establishes that the microbial community in CF airways can modulate Pa occurrence. At the dawn of targeted therapies, it paves the way for characterizing future trends and evolution of infections.

Pulmonary cystic echinococcosis in a child.

This case report describes the presentation, diagnosis, and treatment of a 13-year-old boy with pulmonary cystic echinococcosis. The patient presented with low-volume hemoptysis, and lung imaging revealed a large cystic mass, as well as smaller pseudo-nodular lesions, suggesting a large intrathoracic hydatid cyst and ruptured cysts. The diagnosis was confirmed by a positive echinococcosis Western Blot assay, despite equivocal serology. The treatment consisted of surgical removal of the large cyst using thoracoscopy, along with a two-week course of albendazole and praziquantel, followed by albendazole alone for two years. Analysis of the cyst membrane revealed an Echinococcus granulosus protoscolex. The patient had a successful recovery.

Digital Action Plan (Web App) for Managing Asthma Exacerbations: Randomized Controlled Trial.

BACKGROUND: A written action plan (WAP) for managing asthma exacerbations is recommended. OBJECTIVE: We aimed to compare the effect on unscheduled medical contacts (UMCs) of a digital action plan (DAP) accessed via a smartphone web app combined with a WAP on paper versus that of the same WAP alone. METHODS: This randomized, unblinded, multicenter (offline recruitment in private offices and public hospitals), and parallel-group trial included children (aged 6-12 years) or adults (aged 18-60 years) with asthma who had experienced at least 1 severe exacerbation in the previous year. They were randomized to a WAP or DAP+WAP group in a 1:1 ratio. The DAP (fully automated) provided treatment advice according to the severity and previous pharmacotherapy of the exacerbation. The DAP was an algorithm that recorded 3 to 9 clinical descriptors. In the app, the participant first assessed the severity of their current symptoms on a 10-point scale and then entered the symptom descriptors. Before the trial, the wordings and ordering of these descriptors were validated by 50 parents of children with asthma and 50 adults with asthma; the app was not modified during the trial. Participants were interviewed at 3, 6, 9, and 12 months to record exacerbations, UMCs, and WAP and DAP use, including the subjective evaluation (availability and usefulness) of the action plans, by a research nurse. RESULTS: Overall, 280 participants were randomized, of whom 33 (11.8%) were excluded because of the absence of follow-up data after randomization, leaving 247 (88.2%) participants (children: n=93, 37.7%; adults: n=154, 62.3%). The WAP group had 49.8% (123/247) of participants (children: n=45, 36.6%; mean age 8.3, SD 2.0 years; adults: n=78, 63.4%; mean age 36.3, SD 12.7 years), and the DAP+WAP group had 50.2% (124/247) of participants (children: n=48, 38.7%; mean age 9.0, SD 1.9 years; adults: n=76, 61.3%; mean age 34.5, SD 11.3 years). Overall, the annual severe exacerbation rate was 0.53 and not different between the 2 groups of participants. The mean number of UMCs per year was 0.31 (SD 0.62) in the WAP group and 0.37 (SD 0.82) in the DAP+WAP group (mean difference 0.06, 95% CI -0.12 to 0.24; P=.82). Use per patient with at least 1 moderate or severe exacerbation was higher for the WAP (33/65, 51% vs 15/63, 24% for the DAP; P=.002). Thus, participants were more likely to use the WAP than the DAP despite the nonsignificant difference between the action plans in the subjective evaluation. Median symptom severity of the self-evaluated exacerbation was 4 out of 10 and not significantly different from the symptom severity assessed by the app. CONCLUSIONS: The DAP was used less often than the WAP and did not decrease the number of UMCs compared with the WAP alone. TRIAL REGISTRATION: ClinicalTrials.gov NCT02869958; https://clinicaltrials.gov/ct2/show/NCT02869958.

Genetic Modifiers of Cystic Fibrosis Lung Disease Severity: Whole-Genome Analysis of 7,840 Patients.

Rationale: Lung disease is the major cause of morbidity and mortality in persons with cystic fibrosis (pwCF). Variability in CF lung disease has substantial non-CFTR (CF transmembrane conductance regulator) genetic influence. Identification of genetic modifiers has prognostic and therapeutic importance. Objectives: Identify genetic modifier loci and genes/pathways associated with pulmonary disease severity. Methods: Whole-genome sequencing data on 4,248 unique pwCF with pancreatic insufficiency and lung function measures were combined with imputed genotypes from an additional 3,592 patients with pancreatic insufficiency from the United States, Canada, and France. This report describes association of approximately 15.9 million SNPs using the quantitative Kulich normal residual mortality-adjusted (KNoRMA) lung disease phenotype in 7,840 pwCF using premodulator lung function data. Measurements and Main Results: Testing included common and rare SNPs, transcriptome-wide association, gene-level, and pathway analyses. Pathway analyses identified novel associations with genes that have key roles in organ development, and we hypothesize that these genes may relate to dysanapsis and/or variability in lung repair. Results confirmed and extended previous genome-wide association study findings. These whole-genome sequencing data provide finely mapped genetic information to support mechanistic studies. No novel primary associations with common single variants or rare variants were found. Multilocus effects at chr5p13 (SLC9A3/CEP72) and chr11p13 (EHF/APIP) were identified. Variant effect size estimates at associated loci were consistently ordered across the cohorts, indicating possible age or birth cohort effects. Conclusions: This premodulator genomic, transcriptomic, and pathway association study of 7,840 pwCF will facilitate mechanistic and postmodulator genetic studies and the development of novel therapeutics for CF lung disease.

Respiratory function and sleep in children with myotonic dystrophy type 1.

Myotonic dystrophy type 1 (DM1) is a rare neuromuscular disease in children causing sleep and respiratory disorders that are poorly described in the literature compared to adult forms. This retrospective observational study was performed at the Armand Trousseau University Hospital, Assistance Publique-Hôpitaux de Paris (APHP), Paris, France. We retrospectively collected data from lung function tests, nocturnal gas exchange recordings, and polysomnography of 24 children with DM1. 39% of the children with DM1 reported respiratory symptoms indicative of sleep disordered breathing. Three patients (12%) presented with a restrictive respiratory pattern, 10 (42%) with a sleep apnoea syndrome, mainly of obstructive origin (2/10 with severe obstructive sleep apnea syndrome), and 11 (45%) with nocturnal alveolar hypoventilation. Non-invasive ventilation (NIV) was indicated in 9 (37.5%) children, although tolerance was poor. No significant deterioration in respiratory function or nocturnal gas exchange was observed during the NIV-free period. This study provides new and useful insights into DM1 disease evolution in children to better adapt for respiratory follow-up and management. This highlights the need for future research to better understand the origin of respiratory and sleep disorders in patients with DM1.

COVID-19 and pediatric pulmonology: Feedback from an expert center after the first year of the pandemic.

The coronavirus disease 2019 (COVID-19) outbreak has evolved with different waves corresponding to subsequent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mutations. While the most severe cases have been observed in the elderly and in individuals with underlying comorbidities, severe pediatric and young adult cases have been observed, as well as post-infectious inflammatory syndromes and persistent symptoms leading to long-COVID. This manuscript describes the experience of a pediatric respiratory unit during the first year of the pandemic and reviews the corresponding literature with a special emphasis on children and young people with underlying conditions, such as immunosuppression, sickle cell disease, and cystic fibrosis.