García Acevedo María, Sánchez Códez María Isabel, Peromingo Matute Estrella, Galán Sánchez Fátima, Delgado Martín Beatriz, Quiroga de Castro Aranzazu, Fernández Puentes Verónica, Lubián López Simón, Alonso Ojembarrena Almudena
Department of Pediatrics, Puerta del Mar University Hospital, Av. Ana de Viya, 21, 11009, Cádiz, Spain.
Department of Microbiology, Institute for Research and Innovation in Biomedical Sciences (INiBICA), Cádiz, Spain.
Eur J Pediatr. 2025 Sep 17;184(10):621. doi: 10.1007/s00431-025-06448-3.
Lower respiratory tract infections (LRTIs) remain a major cause of morbidity and mortality in young children worldwide, with respiratory syncytial virus (RSV) as the leading pathogen. This study aims to evaluate the impact of implementing universal nirsevimab prophylaxis on the clinical and lung ultrasound (LUS) presentations of LRTIs in hospitalized pediatric patients. We conducted a prospective observational study at a tertiary pediatric hospital in southern Spain, including 197 children under 14 years of age hospitalized with LRTIs. Two periods were differentiated: the pre-nirsevimab period (October 2022-April 2023) and the post- nirsevimab period (October 2023-April 2024). Patients were classified by clinical diagnosis and microbiological results. LUS was performed upon admission, after 48 h, and upon discharge. Clinical severity scores, oxygen requirements, intensive care admissions, and length of stay were recorded. A total of 94 patients were included in the pre-nirsevimab period, and 103 in the post-nirsevimab period. During the second period, admissions due to bronchiolitis decreased (61.7% vs. 34.0%, p = 0.001), whereas those due to pneumonia and asthma exacerbations increased. RSV-related admissions dropped significantly (69.6% vs. 32.0%, p = 0.001), while there was a rise in metapneumovirus and Mycoplasma pneumoniae infections. Post-nirsevimab patients were older (13 vs. 5.5 months, p = 0.023) and required less oxygen (72.8% vs. 86.0%, p = 0.023) and fluid therapy (9.7% vs. 30.9%, p = 0.001). There were no differences in ultrasound scores, sizes, numbers or locations of consolidations.
A shift in etiology and age distribution was observed, alongside an increase in viral pneumonias and asthma exacerbations in the post-nirsevimab period. However, ultrasound parameters remained similar across periods. These findings support the role of nirsevimab in modifying the burden and clinical spectrum of pediatric respiratory infections.
• Universal nirsevimab prophylaxis reduces RSV-related hospitalizations and bronchiolitis incidence, modifying the clinical burden of pediatric LRTIs. However, its impact on LUS findings in hospitalized children has not been well characterized.
• Despite clinical changes after universal nirsevimab prophylaxis (including lower RSV incidence and reduced oxygen needs), LUS profiles of LRTIs remained unchanged, suggesting stable imaging findings regardless of shifts in viral etiology.
下呼吸道感染（LRTIs）仍然是全球幼儿发病和死亡的主要原因，呼吸道合胞病毒（RSV）是主要病原体。本研究旨在评估实施通用的尼塞韦单抗预防措施对住院儿科患者LRTIs临床及肺部超声（LUS）表现的影响。我们在西班牙南部一家三级儿科医院进行了一项前瞻性观察性研究，纳入197例因LRTIs住院的14岁以下儿童。分为两个时期：尼塞韦单抗使用前时期（2022年10月至2023年4月）和尼塞韦单抗使用后时期（2023年10月至2024年4月）。患者根据临床诊断和微生物学结果进行分类。入院时、48小时后及出院时进行LUS检查。记录临床严重程度评分、氧气需求、重症监护病房入住情况及住院时间。尼塞韦单抗使用前时期纳入94例患者，使用后时期纳入103例患者。在第二个时期，因细支气管炎入院的患者减少（61.7%对34.0%，p = 0.001），而因肺炎和哮喘加重入院的患者增加。RSV相关入院显著下降（69.6%对32.0%，p = 0.001），而偏肺病毒和肺炎支原体感染有所增加。使用尼塞韦单抗后的患者年龄较大（13个月对5.5个月，p = 0.023），氧气需求较少（72.8%对86.0%，p = 0.023），液体治疗需求较少（9.7%对30.9%，p = 0.001）。超声评分、实变的大小、数量或位置无差异。
观察到病因和年龄分布发生变化，尼塞韦单抗使用后时期病毒性肺炎和哮喘加重有所增加。然而，各时期超声参数保持相似。这些发现支持了尼塞韦单抗在改变儿科呼吸道感染负担和临床谱方面的作用。
• 通用的尼塞韦单抗预防措施可降低RSV相关住院率和细支气管炎发病率，改变儿科LRTIs的临床负担。然而，其对住院儿童LUS检查结果的影响尚未得到充分描述。
• 尽管通用的尼塞韦单抗预防措施后出现了临床变化（包括RSV发病率降低和氧气需求减少），但LRTIs的LUS特征保持不变，表明无论病毒病因如何变化，影像学表现稳定。
