Objective
To investigate the etiology of pleural effusions.
Methods
All adult patients with pleural effusions of unknown etiology admitted to this hospital between January 2011 and December 2013 were investigated. The etiological data of these patients with pleural effusion were retrospectively reviewed.
Results
During the 3-year period, 1 541 patients eventually were included in this study. The most frequent cause of pleural effusions was bacterial infection (38.7%), followed by malignancy (23.7%), congestive heart failure (13.1%), and tuberculosis (10.7%). The etiology of 120 patients (7.8%) remained uncertain.
Conclusions
The most frequent cause of pleural effusion is bacterial infection, followed by malignancy, cardiac failure, and tuberculosis. These four etiologies account for over 85 percent of all pleural effusions.
