Spectrum and outcome in patients with unilateral pleural effusion admitted in a tertiary care hospital

Background: Unilateral pleural effusion is a challenge for a physician as the differential diagnosis is varied; sparse epidemiological data are available from India on this subject. Methods: We prospectively studied consecutive adult patients (aged >18 years) presenting with unilateral pleural effusion who underwent thoracocentesis with or without radiological guidance for diagnostic workup. Results: Over a period of 1 year, 116 patients admitted with unilateral pleural effusion were included, majority (63.8%) were in the age group of 20–60 years. Most common presenting symptoms were shortness of breath (56%), fever (53.4%), cough (52.5%), chest pain (35.3%), anorexia (34.5%) and weight loss (18.9%). Ninety-nine patients (85.3%) had exudative and 17 patients (14.6%) had transudative pleural effusion. Amongst exudative, tuberculosis (TB) pleural effusion was the most common cause (45.7%) followed by para-pneumonic (12.9%), malignant (10.3%), among others. TB (44.8%) and malignancy (10.3%) were common aetiologies among the lymphocyte-predominant effusions, whereas para-pneumonic effusion (11.2%) and empyema (4.3%) were common aetiologies amongst the neutrophil-predominant effusions. Pleural fluid lymphocyte-to-neutrophil ratio >0.75 increased the sensitivity and specificity to diagnose TB pleural effusion. Conclusions: Patients with TB pleural effusion were comparatively younger as compared to patients with malignant and para-pneumonic pleural effusion. Most pleural effusions resolved with treatment of underlying cause.