Diagnostic Yield of Ultrasound-Guided Tru-Cut Pleural Biopsy in Undiagnosed Exudative Lymphocytic Pleural Effusion in a Tertiary Healthcare Setting.

BACKGROUND: Exudative lymphocytic pleural effusion (ELPE) has many causes including tuberculosis and malignancy. The traditional methods, such as ultrasound-guided Tru-cut pleural biopsy (UGTPB), ensure enhanced visualizations with a reduced rate of complications. The aim of this study was to establish the diagnostic yield and safety profile of UGTPB in patients with undiagnosed ELPE. METHODS: This was a prospective observational study that involved 150 patients having undiagnosed ELPE. It was conducted in a hospital in Pakistan from January to December 2024. Patients who met the light criteria of confirmed exudative, lymphocytic effusion, negative initial cytology, Ziehl-Neelsen stain, Gram stain, and cartridge-based nucleic acid amplification test (CBNAAT) were enrolled. Measures of outcomes included diagnostic yield, etiological distribution, and complications of the procedure. The statistical analysis was conducted using IBM SPSS Statistics for Windows, version 26.0 (IBM Corp., Armonk, New York, United States), and Chi-square and t-tests were used; significance level was p = 0.05. RESULTS: UGTPB made a conclusive diagnosis in 132 participants with an accuracy of 88%. The diagnosis of malignancy was made in 60 (40.0%) cases, tuberculosis in 52 (35.0%), and other causes in 20 (13.0%) cases. Eighteen (12.0 %) cases were not diagnosed. The sensitivity and specificity were 85% and 95%, respectively. There were three (2.0 %) patients with pneumothorax and four (2.7%) patients with minor bleeding without any major adverse events. CONCLUSION: UGTPB is a low-risk, minimally invasive, and very effective diagnostic modality of ELPE. Its similarity to medical thoracoscopy with fewer complications contributes to its application as a first-line diagnostic instrument, especially in resource-limited areas.