Chylothorax: diagnosis by lipoprotein electrophoresis of serum and pleural fluid.

This report describes a 31-year-old woman who underwent a technically difficult left pneumonectomy for tuberculosis and developed thereafter a large left pleural effusion which was milky in colour. A traumatic chylothorax was suspected, and the diagnosis was confirmed by simultaneous fasting pleural and serum lipid studies and lipoprotein electrophoresis. The latter study was especially helpful in confirming the chylous nature of the fluid in that it revealed a marked chylomicron band at the origin; this was not present in the patient's serum nor in the pleural fluid of five patients with other disease states studied as controls.