Mackenzie Grant
Basse Field Station, Medical Research Council Unit, The Gambia, c/o MRC Unit, PO Box 273, Banjul, Gambia.
Murdoch Childrens Research Institute, Melbourne, Australia.
Pneumonia (Nathan). 2016 Aug 22;8:14. doi: 10.1186/s41479-016-0012-z. eCollection 2016.
Following the publication of a volume of focused on diagnosis, the journal's Editorial Board members debated the definition and classification of pneumonia and came to a consensus on the need to revise both of these. The problem with our current approach to the classification of pneumonia is twofold: (i) it results in widespread empirical, and often unnecessary, use of antimicrobials that contributes to pathogen resistance; and (ii) it contributes to heterogeneity among the groups of subjects compared in research, causing misclassification bias and mixtures of effects that threaten internal validity. After outlining the problem of classification, this commentary describes the strengths and weaknesses of a range of systems for the classification of pneumonia. The commentary then calls for debate to generate consensus classifications in the field, proposing a working definition and way forward focusing on the following three points: (i) pneumonia should be defined as an acute infection of the lung parenchyma by various pathogens, excluding the condition of bronchiolitis; (ii) defining pneumonia as a group of specific (co)infections with different characteristics is an ideal that currently has limited use, because the identification of aetiologic organisms in individuals is often not possible (however, the benefits of classifying pneumonia into specific, more homogenous phenotypes should be carefully considered when designing research studies); and (iii) investigation of more homogenous pneumonia groupings is achievable and is likely to yield more rapid advances in the field.
在一本专注于诊断的专刊出版后，该期刊的编辑委员会成员就肺炎的定义和分类展开了讨论，并就对这两者进行修订的必要性达成了共识。我们目前对肺炎进行分类的方法存在两方面问题：（i）这导致广泛地经验性使用抗菌药物，且常常是不必要的使用，这会导致病原体耐药性；（ii）这导致在研究中进行比较的受试者群体之间存在异质性，造成错误分类偏差以及效应混合，从而威胁到内部效度。在概述了分类问题之后，本评论描述了一系列肺炎分类系统的优缺点。该评论随后呼吁展开辩论以在该领域形成共识分类，提出了一个工作定义和前进方向，重点关注以下三点：（i）肺炎应被定义为肺实质被各种病原体的急性感染，不包括细支气管炎的情况；（ii）将肺炎定义为一组具有不同特征的特定（合并）感染是一个目前用途有限的理想情况，因为在个体中往往无法确定病原体（然而，在设计研究时应仔细考虑将肺炎分类为特定的、更同质的表型的益处）；（iii）对更同质的肺炎分组进行研究是可行的，并且可能会在该领域取得更快的进展。
