Accuracy of Lung Ultrasonography in the Diagnosis of Pneumonia in Adults: Systematic Review and Meta-Analysis

Background: Some studies suggest that lung ultrasonography could be useful for diagnosing pneumonia; moreover, it has a more favorable safety profile and lower cost than chest radiography and CT. The aim of this study was to assess the accuracy of bedside lung ultrasonography for diagnosing pneumonia in adults through a systematic review and meta-analysis.

Methods: We searched MEDLINE, Scopus, The Cochrane Library, Web of Science, DARE, HTA Database, Google Scholar, LILACS, ClinicalTrials.gov, TESEO, and OpenGrey. In addition, we reviewed the bibliographies of relevant studies. Two researchers independently selected studies that met the inclusion criteria. Quality of the studies was assessed in accordance with the Quality Assessment of Diagnostic Accuracy Studies tool. The summary receiver operating characteristic (SROC) curve and a pooled estimation of the diagnostic odds ratio (DOR) was estimated using a bivariate random-effects analysis. The sources of heterogeneity were explored using predefined subgroup analyses and bivariate meta-regression.

Results: Sixteen studies (2,359 participants) were included. There was significant heterogeneity of both sensitivity and specificity according to the Q test, without clear evidence of threshold effect. The area under the SROC curve was 0.93, with a DOR at the optimal cutpoint of 50 (95% CI, 21-120). A tendency toward a higher area under the SROC curve in high-quality studies was detected; however, these differences were not significant after applying the bivariate meta-regression.

Conclusions: Lung ultrasonography can help accurately diagnose pneumonia, and it may be promising as an adjuvant resource to traditional approaches.