Pediatric Clinic 1, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via Commenda 9, 20122 Milan, Italy.
Eur J Clin Microbiol Infect Dis. 2013 Jul;32(7):877-81. doi: 10.1007/s10096-013-1821-0. Epub 2013 Jan 25.
This study was conducted to evaluate the association between pneumococcal DNA load and parapneumonic pleural effusion (PPE) in children with community-acquired pneumonia. Bacterial load was quantified and related to the presence of PPE with or without empyema in 72 otherwise healthy children aged ≤5 years who were hospitalised because of radiographically confirmed CAP and showed a real-time polymerase chain reaction that was positive for Streptococcus pneumoniae. The proportion of children with a high bacterial load (i.e. ≥265 DNA copies/mL) was larger among the subjects with PPE than those without it. Multivariate analysis showed that a high bacterial load was significantly associated with PPE (OR 8.65; 95% CI 1.10-67.8 vs a bacterial load of <125 copies/mL). Children with infection due to pneumococcal serotype 19A were at highest risk of developing PPE (OR 7.44; 95% CI 1.10-50.4 vs all other typeable serotypes). The patients with CAP due to pneumococcal serotypes that are not included in the 13-valent conjugate vaccine (PCV13) were more frequently affected by PPE than those with infections associated with serotypes included in the vaccine, except for serotype 19A. Bacterial loads of ≥265 DNA copies/mL are significantly associated with PPE, and serotype 19A is significantly associated with a high bacterial load and the development of PPE. The mean bacterial load of the patients with empyema was higher than that of patients with simple PPE. Although further studies are required, it seems that serotypes not included in PCV13 can play a major role in causing a higher bacterial load and PPE.
本研究旨在评估肺炎链球菌 DNA 载量与儿童社区获得性肺炎并发脓胸的关系。对 72 名年龄≤5 岁、因影像学证实的社区获得性肺炎住院且实时聚合酶链反应显示肺炎链球菌阳性的健康儿童进行细菌载量定量，并将其与有无脓胸的胸腔渗出液进行相关分析。在有胸腔渗出液的患儿中，高细菌载量（即≥265 拷贝/ml）患儿的比例大于无胸腔渗出液的患儿。多变量分析显示，高细菌载量与胸腔渗出液显著相关（比值比 8.65；95%置信区间 1.10-67.8 比细菌载量<125 拷贝/ml）。感染 19A 型肺炎链球菌的患儿发生胸腔渗出液的风险最高（比值比 7.44；95%置信区间 1.10-50.4 比其他可分型血清型）。与疫苗包含的血清型感染相比，不包含在 13 价结合疫苗（PCV13）中的肺炎链球菌血清型感染导致 CAP 的患儿更易发生胸腔渗出液，19A 型血清型除外。细菌载量≥265 拷贝/ml 与胸腔渗出液显著相关，19A 型血清型与高细菌载量和胸腔渗出液的发生显著相关。脓胸患儿的平均细菌载量高于单纯胸腔渗出液患儿。虽然还需要进一步研究，但似乎 PCV13 不包含的血清型可能在导致高细菌载量和胸腔渗出液方面发挥主要作用。
