The diagnostic yield of closed needle pleural biopsy in exudative pleural effusion: a retrospective 10-year study

Background: Pleural effusion is a common presentation in clinical practice. About 40% of exudative pleural effusion is unable to be diagnosed through thoracentesis, and closed pleural biopsy (CPB) is needed. This study was designed to investigate the diagnostic yield of CPB in exudative pleural effusion. Methods: This was a retrospective 10-year study of patients with unexplained exudative pleural effusion who underwent CPB in two centers. Malignant pleural effusion (MPE) was diagnosed when there was histopathological evidence of pleural tissue, pulmonary tissue, or pleural fluid. Tuberculous pleural effusion (TPE) was confirmed when granuloma or coagulative necrosis was observed in pleural tissue, Ziehl-Neelsen acid-fast staining was positive, or adenosine deaminase (ADA) in pleural effusion was higher than 35IU with clinical symptoms of TB or.-interferon increased with symptoms of TB. Results: A total of 644 patients were enrolled, of which 479 were specifically diagnosed (217 patients with TPE and 262 patients with MPE). The sensitivity of CPB in the diagnosis of MPE was 51.5%. Among the pathological types of MPE, lung adenocarcinoma accounted for 77.9% (204/262) of cases, making up the largest proportion. The sensitivity of CPB for diagnosing TPE was 68.7%. Conclusions: CPB has a relatively high sensitivity in the diagnosis of exudative pleural fluid, especially in relation to tuberculous lesions. CPB could provide an alternative technique in clinical practice, especially for basic hospital units without thoracoscopy.