Pleural fluid lysozyme in human disease.

Lysozyme content was measured in the plasma and pleural fluid of 110 patients with pleural effusions of various causes. The concentration of pleural fluid lysozyme was significantly higher (P less than .001) in patients with tuberculous pleurisy than in those with primary pulmonary carcinoma, metastatic carcinoma of the lung, connective tissue disease, nonspecific pleurisy, or congestive heart failure.