[Usefulness of the determination of lipids parameters in pleural effusions]. / Utilidad de la determinación de parámetros grasos en los derrames pleurales.

In 160 patients with pleural effusion, consecutively studied in our section, cholesterol and triglyceride concentrations and lipidogram were prospectively measured in the pleural fluid and the blood to rule out the possible occurrence of chylothorax. For the diagnosis of chylothorax the presence of chylomicrons in the pleural fluid was required. The macroscopic appearance of the fluid was a poor indicator of the presence of chylothorax, as in three of the seven patients in which the latter was discovered the characteristically reported milky appearance of the pleural fluid was not found. The mean value of triglycerides in the chylous effusions (162.3 +/- 34.8 mg/dl) was significantly higher (p less than 0.001) than in nonchylous effusions (45.8 +/- 26.3 mg/dl). All patients with chylothorax had triglyceride values higher than 110 mg/dl; using this figure as the cut-off value, 7.5% of the patients with pleural effusion were selected as those in whom, irrespectively of the macroscopic appearance of their effusions, the performance of lipidogram would be indicated to rule out chylothorax.