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Licensed Unlicensed Requires Authentication Published by De Gruyter July 4, 2022

Diagnostic utility of pleural cell-free nucleic acids in undiagnosed pleural effusions

  • Wen Zhao , Xi-Shan Cao , Yu-Ling Han , Xu-Hui Wen , Wen-Qi Zheng and Zhi-De Hu ORCID logo EMAIL logo


Pleural effusion (PE) is a common sign caused by various disorders. Microbiology, histology and cytology are reference standards for these disorders. However, these diagnostic tools have limitations, including invasiveness, high cost, long turnaround time, and observer-dependent. Soluble biomarkers in pleural fluid (PF) are promising diagnostic tools because they are mininvasive, economical, and objective. Recent studies have revealed that some cell-free nucleic acids (e.g., DNA, mRNA, microRNA, and lncRNA) in PF are potential diagnostic markers for many disorders. Here, we review the performance of PF cell-free nucleic acids for differentiating and stratification of PE.

Corresponding author: Zhi-De Hu, PhD, Department of Laboratory Medicine, The Affiliated Hospital of Inner Mongolia Medical University, Hohhot 010010, P.R. China, E-mail:

Award Identifier / Grant number: 81860501

  1. Research funding: This work was supported by the National Natural Science Foundation of China (81860501).

  2. Author contributions: Zhi-De Hu designed and supervised the study. Wen Zhao collected the data from previous studies and drafted the manuscript. Xi-Shan Cao, Yu-Ling Han, and Xu-Hui Wen provided administrative support and provided intellectual contributions to the manuscript. Zhi-De Hu and Wen-Qi Zheng critically reviewed and edited the manuscript. All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

  3. Competing interests: The authors have no conflicts of interest to declare.

  4. Conflict of interest: Not applicable.

  5. Ethical approval: Not applicable.


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Received: 2022-05-27
Accepted: 2022-06-22
Published Online: 2022-07-04
Published in Print: 2022-09-27

© 2022 Walter de Gruyter GmbH, Berlin/Boston

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