Efficacy and safety of diagnostic thoracoscopy in undiagnosed pleural effusions

The differential diagnosis of pleural effusions can present a considerable challenge, and the etiology of pleural effusions varies depending on the population studied.

This study aimed to assess the efficacy and safety of medical thoracoscopy in the diagnosis of patients with undiagnosed pleural effusions in a Chinese population.

Between July 2005 and June 2014, medical thoracoscopy (MT) using the semirigid instrument was performed in 833 patients with pleural effusions of unknown etiology in our Institute, where diagnostic thoracocentesis or/and blind pleural biopsy had failed to yield an answer. Demographic, radiographic, procedural, and histological data were recorded and analyzed.

During this 9-year study, satisfactory pleural biopsy samples were obtained in 833 patients, and MT revealed malignant pleural effusion in 342 (41.1%) patients, benign pleural effusion in 429 (51.5%) patients, and 62 (7.4%) patients could not get definite diagnoses. The overall diagnostic efficiency of MT was 92.6% (771/833). After MT, the only severe complication was empyema, seen in 3 patients (0.4%). The most common minor complication was transient chest pain (44.1%) from the indwelling chest tube.

MT is an effective and safe procedure for diagnosing pleural effusions of undetermined causes. In areas with high tuberculosis prevalence, MT should be particularly helpful in the differential diagnosis of tuberculous pleural effusion.