Abstract
Objective: To determine the frequency and etiology of pleural effusion among ESRD patients on maintenance hemodialysis.
Methodology: This cross-sectional study was conducted at SIUT Karachi from April 2013 to October 2013 and included 250 adult ESRD patients who were on maintenance hemodialysis for at least 6 months and had been diagnosed pleural effusion. Presence of the effusion was confirmed radiologically and pleural fluid for physical examination, biochemical analysis (sugar, protein, LDH) and cell count. Pleural fluid was sent for culture if it was turbid or had high leucocyte count.
Results: Pleural effusion was transudative in 133 (53.2%) patients and exudative in 117(46.8%) cases, based on Light's criteria. Fluid overload and congestive heart failure (CHF) accounted for all the patients with transudative effusion and lead to pleural effusion in 101 (40.4%) and 32 (12.8%) patients out of 250. Tuberculosis, empyema (parapneumonic effusion) and uremic pleuritis caused exudative pleural effusion in 77 (30.8%), 39 (15.6%) and one (0.4%) out of 250 patients . Frequency of pleural effusion secondary to fluid overload, CHF, tuberculosis and empyema was highest among patients on dialysis for 1 to 2 years and lowest among those who were dialysis dependent for more than 4 years. The patients with CHF were older than patients with other diseases leading to pleural effusion.
Conclusion: Pleural effusion is still a common problem among dialysis dependent ESRD patients and the most frequent etiologies included uremia followed by TB, empyema and CHF.

Key words: Pleural, effusion, tuberculous, renal, empyema, transudate, exudate