Community acquired pneumonia (CAP) is a prevalent infectious disease often requiring hospitalization, although its diagnosis remains challenging as there is no gold standard test. In severe CAP, clinical and radiologic criteria have poor sensitivity and specificity, and microbiologic documentation is usually delayed and obtained in less than half of sCAP patients. Biomarkers could be an alternative for diagnosis, treatment monitoring and establish resolution. Beyond the existing evidence about biomarkers as an adjunct diagnostic tool, most evidence comes from studies including CAP patients in primary care or emergency departments, and not only sCAP patients. Ideally, biomarkers used in combination with signs, symptoms, and radiological findings can improve clinical judgment to confirm or rule out CAP diagnosis, and may be valuable adjunctive tools for risk stratification, differentiate viral pneumonia and monitoring the course of CAP. While no single biomarker has emerged as an ideal one, CRP and PCT have gathered the most evidence. Overall, biomarkers offer valuable information and can enhance clinical decision-making in the management of CAP, but further research and validation are needed to establish their optimal use and clinical utility.

中文翻译：

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生物标志物：它们对严重社区获得性肺炎有用吗？

社区获得性肺炎（CAP）是一种流行的传染病，通常需要住院治疗，但由于没有金标准测试，其诊断仍然具有挑战性。对于严重的 CAP，临床和放射学标准的敏感性和特异性较差，并且微生物学记录通常会被延迟，只有不到一半的 sCAP 患者才能获得。生物标志物可以作为诊断、治疗监测和确定解决方案的替代方案。除了关于生物标志物作为辅助诊断工具的现有证据之外，大多数证据来自包括初级保健或急诊科的 CAP 患者的研究，而不仅仅是 sCAP 患者。理想情况下，生物标志物与体征、症状和放射学结果结合使用可以改善临床判断，以确认或排除 CAP 诊断，并且可能是风险分层、区分病毒性肺炎和监测 CAP 病程的有价值的辅助工具。虽然还没有一种生物标志物成为理想的生物标志物，但 CRP 和 PCT 已经收集了最多的证据。总体而言，生物标志物提供了有价值的信息，可以增强 CAP 管理的临床决策，但需要进一步的研究和验证来确定其最佳用途和临床效用。