Plasma and serum concentrations of DNA in pulmonary thromboembolism.

The value of circulating DNA concentrations in the diagnosis of pulmonary embolism (PE) was assessed in 68 consecutive patients, of which 36 (Group 1) had clinical symptoms suggesting PE. The diagnosis of PE was established in 13 patients on the basis of pulmonary angiography (PA) (8 patients) and high probability ventilation-perfusion lung scanning (VPS) (5 patients). Pulmonary embolism was ruled out in 23 patients (by PA, 9 patients; by VPS, 14 patients). We found abnormally high DNA concentrations in 26 of the 36 patients (72%) with suggested PE, but there was no significant differences between patients with and patients without PE (p less than 0.05). The results were compared with the DNA concentrations in the remaining 32 patients (16 medical and 16 surgical cases) who had no clinical evidence of PE (Group 2). Increased DNA concentrations were found in 21 of these (66%). There was no significant difference in mean DNA concentrations between Group 1 and Group 2 (p less than 0.05). We conclude that pulmonary angiography and high probability ventilation-perfusion scanning remain the most reliable methods for the diagnosis of PE.