Original Research

Diagnostic Accuracy of Pleural Fluid Protein in DifferentiatingTuberculous and Malignant Pleural Effusion

Karishma Rehman
MTI Khyber Teaching Hospital Peshawar
Mohammad Younas
MTI Khyber Teaching Hospital Peshawar
Rukhsana Javed Farooqi
MTI Khyber Teaching Hospital Peshawar
Rabia Saeed
MTI Khyber Teaching Hospital Peshawar
Sheema Sajjad
MTI Khyber Teaching Hospital Peshawar
Saadia Ashraf
MTI Khyber Teaching Hospital Peshawar

✉ Correspondence: Karishma Rehman Email: karishmarehman46661@import.invalid

DOI https://doi.org/10.70302/jpsim.v7i2.2628
Volume: 7, Issue 2 Pages: 141–145 Published: 03 Jun 2026
Received: 16 Dec 2025 Revised: 13 Apr 2026 Accepted: 04 May 2026 Published Online: 03 Jun 2026

Abstract

Objective

The utility of pleural fluid protein in differentiating between malignant and tuberculous conditions in patients with pleural effusions, with histology serving as the gold standard for diagnosis.

Methods

Cross-sectional (validation) study. Patients were referred from in- and out-of-door patient departments. Patients fulfilling the inclusion criteria underwent Abrams needle biopsies according to routine and following the obtaining of informed written consent, and the pleural tissue was examined by a single histopathologist. A pleural fluid protein cut-off value of 5 g/dl for tuberculosis was marked.

Results

In this study, we identified 209 patients with suspected tuberculous or malignant pleural effusions. Mean age was 42.7 + 10.8 SD. In the diagnosis of cancer, pleural fluid protein has a positive predictive value of 35.9%, a negative predictive value of 98.82%, and sensitivity and specificity of 87.5% and 87.05%, respectively. The overall diagnostic performance of pleural fluid protein for cancer was 87.08%.

Conclusion

When combined with a suitable clinical setting, the pleural fluid total protein level is a useful diagnostic tool for suspected tuberculous or malignant pleural effusions.

Keywords
tuberculous pleural effusion malignant pleural effusion exudates pleural biopsy pleural fluid protein.

How to Cite This Article

Rehman K, Younas M, Farooqi RJ, Saeed R, Sajjad S, Ashraf S. Diagnostic Accuracy of Pleural Fluid Protein in DifferentiatingTuberculous and Malignant Pleural Effusion. J Pak Soc Intern Med. 2026;7(2):141–145. doi:10.70302/jpsim.v7i2.2628

Conflict of Interest

All authors declare no competing interests.

Disclosed in accordance with ICMJE and COPE guidelines.

Funding

No specific funding was received for this research.

Funder information follows the Crossref Funder Registry standard.

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CC BY CC BY 4.0 This article is published under the Creative Commons Attribution 4.0 International License. May be shared and adapted with attribution. © 2026 Journal of Pakistan Society of Internal Medicine.
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