Diagnostic value of pleural fluid cytologic examination

Rolandas Zablockis, Remigijus Nargėla

Clinic of Pulmonology and Allergology, Vilnius University, Lithuania

Key words: pleural fluid, cytology, hematocrit.

Summary. The study included 200 patients with pleural effusion. Pleural effusions were transudative in 48 (24%) and exudative in 152 (76%) of cases. Congestive cardiac failure (14.5%), nephrotic syndrome (5.5%), and liver cirrhosis (2.5%) were the most common etiological diagnoses of transudate cases. Malignant effusion (16.5%), pneumonia (13%), pleural empyema (9%), tuberculosis (6%), and pulmonary embolism (5.5%) were the most common etiological diagnoses of exudative cases. Thirty-two (16%) cases of exudative pleural effusions were of undertermined etiology. Polymorphonuclear leucocytes predominated in 48 patients with exudative pleural effusions. The most common etiological diagnoses were pneumonia (41.67%), pleural empyema (39.59%) and pulmonary embolism (10.42%). Lymphocytes in pleural fluid were predominant in 63 patients, with malignant (6.34%), tuberculous pleurisy (19.02%), pulmonary embolism (6.34%), trauma (6.34%), and (46.11%) cases in patients with pleural exudate undertermined etiology. Eosinophyls were predominant in 16 (8%) patients with exudative pleural effusions. The most common etiology of eosinophilic pleural fluid were pneumonia (37.5%), malignant pleural effusion (25%), pulmonary embolism (12.5%), pyopneumothorax (6.25%) and trauma 6.25%. From 16 patients with eosinophilic pleural exudate, in 31% cases air, in 12.5% blood in pleural fluid were determined and in 12.5% cases previous pleural puncture was performed. Pleural fluid eosinophilia is most commonly associated with the presence of air or blood in the pleural fluid (correalation index 0.82). Malignant pleural effusions were determined in 33 patients. Malignant cells in pleural fluid were identified in 25 cases. The diagnostic sensitivity of pleural fluid cytology for malignant pleural effusions were 76%. Hemoragic pleuritis was determined in 18 and hemothorax in 4 patients. Etiology of hemothorax were trauma (75%) and coaguliopathia (25%). Most common etiological diagnoses of hemoragic pleuritis were neoplasia (33.3%), pulmonary embolism (16.65%), trauma (16.65%), pneumonia (11.11%), and congestive cardiac failure (11.11%). Diagnostic sensitivity and specifity of hemoragic pleuritis is low, 58% and 45% respectively.

Correspondence to R. Zablockis, Clinic of Pulmonology and Allergology, Vilnius University, Santariškių 2, 2600 Vilnius, Lithuania. E-mail: rzablockis@takas.lt

Received 16 January 2002, accepted 12 November 2002