Chest CT-scan (CT) exceeds chest X-ray (CXR) to diagnose community-acquired pneumonia (CAP) but actual use and results remain unclear. We examine whether CT performed at ED visit improved ED diagnosis of CAP as compared to a final diagnosis of CAP at hospital discharge (gold standard diagnosis for the study), and how it impacts relevant clinical outcomes. This retrospective monocenter observational study was based on the analysis of the hospital database. Patients with a diagnosis of CAP in the ED (ICD-10 codes: J110, J111, from J12- to J18-, J440, J690, U0710, and U0711) were included. We compared ED patients who were diagnosed with CAP using CXR and CT. We measured diagnostic consistency, duration of ED visit, percentage of CXR and CT during hospital stay, hospital length-of-stay, ICU admission, and in-hospital mortality. Multivariate analysis was adjusted for CRB65 score by multiple logistic regression analysis for binary outcomes and by multivariate analysis of variance for continuous outcomes. We included 994 ED patients with an initial diagnosis of CAP (751 receiving CXR, 243 receiving CT). CT prescription in the ED increased over time (P < 0.001). In patients admitted after ED, CT improved diagnosis consistency for CAP [88.2% vs. 80.9%; difference 7.3% (95% confidence interval 1.2–13.3%)] with a trend for lower hospital length-of-stay [10.2 vs. 12.2 days; difference −2.0 (95% confidence interval −3.9 to −0.1)], but not ICU admission (P = 0.09) and in-hospital mortality (P = 0.056). Diagnosis of patients admitted with CAP improved when CT was obtained at ED visit. These results should be reproduced at a larger scale to test whether early CT conserves healthcare resources.

胸部 CT 扫描 (CT) 超过胸部 X 射线 (CXR) 来诊断社区获得性肺炎 (CAP)，但实际使用和结果仍不清楚。我们检查了与出院时 CAP 的最终诊断（研究的金标准诊断）相比，在 ED 就诊时进行的 CT 是否改善了 CAP 的 ED 诊断，以及它如何影响相关的临床结果。这项回顾性单中心观察性研究基于对医院数据库的分析。包括在 ED 诊断为 CAP 的患者（ICD-10 代码：J110、J111、从 J12- 到 J18-、J440、J690、U0710 和 U0711）。我们比较了使用 CXR 和 CT 诊断为 CAP 的 ED 患者。我们测量了诊断的一致性、急诊就诊的持续时间、住院期间 CXR 和 CT 的百分比、住院时间、入住 ICU 和住院死亡率。通过对二元结果的多元逻辑回归分析和对连续结果的多变量方差分析，对 CRB65 评分进行了多变量分析。我们纳入了 994 名初步诊断为 CAP 的 ED 患者（751 名接受 CXR，243 名接受 CT）。急诊科的 CT 处方随时间增加（P < 0.001)。在 ED 后入院的患者中，CT 提高了 CAP 的诊断一致性 [88.2% vs. 80.9%；差异 7.3%（95% 置信区间 1.2-13.3%）]，住院时间缩短 [10.2 天 vs. 12.2 天；差异 -2.0（95% 置信区间 -3.9 至 -0.1）]，但不是 ICU 入院（P = 0.09）和住院死亡率（P = 0.056）。在 ED 就诊时获得 CT 后，CAP 入院患者的诊断得到改善。这些结果应该在更大范围内重现，以测试早期 CT 是否可以节省医疗资源。