Pleuroscopy Early Experience in the Exudative Pleural Effusion of Unknown Etiology

Background: Pleuroscopy (medical thoracoscopy) is a minimally invasive procedure to inspect and perform a biopsy of the pleural space as well as to perform therapeutic interventions; pleural fluid drainage and pleurodesis. Materials and Methods: In a retrospective study in Kasra Hospital, Tehran,Iran, the patients with exudative pleural effusion of unknown etiology who underwent pleuroscopy, were evaluated. These patients had negative smears and cultures for infective agents. Also, the cytological review was negative for malignancy. Results: 62 patients had undergone pleuroscopy, of which 29 (46.7) were men. After the final evaluation, 47 patients (75.8%) had a definite pathologic diagnosis, of which 39 patients (82.9%) had cancer. Through these 39 cases, 18 cases (46.1%) had a history of the previously confirmed cancer, in which pleural pathology was consistent with the initial diagnosis. In 21 cases (53.9%), metastatic cancers were detected without a previous history. From a total of 47 cases with definite pathologic diagnosis, 8 cases (17%) had histopathologic evidence of granulomatous lesions consistent with tuberculosis, and 15 patients (24%) showed non-specific inflammatory lesions. There was no morbidity and mortality among these patients. Discussion: Considering that pleuroscopy is a safe procedure with high diagnostic accuracy, malignancy is the most common finding in the exudative pleural effusion of unknown etiology, which increases the importance of this procedure in these cases to prevent wasting time and smear-negative anti-TB treatment.