Adjusting D-dimer to lung disease extent to exclude Pulmonary Embolism in COVID-19 patients (Co-LEAD)
Résumé
Introduction: D-dimer measurement is a safe tool to exclude pulmonary embolism (PE) but its specificity decreases in COVID-19. Our aim was to derive a new algorithm with specific D-dimer threshold in COVID-19 patients. Methods: We conducted a French multicenter, retrospective cohort study among 774 COVID-19 patients with suspected PE. D-dimer threshold adjusted to computed tomography (CT) extent of lung damage was derived in a patient set (n=337), and its safety assessed in an independent validation set (n=337). Results: According to ROC curves, in the derivation set D-dimer safely excluded PE, with one false negative when using a 900 ng/mL threshold when lung damage extent was <50% and 1700 ng/mL when lung damage extent was ≥50%. In the derivation set, the algorithm sensitivity was 98.2% (95% CI: 94.7–100.0) and its specificity 28.4% (95% CI: 24.1–32.3). The negative likelihood ratio (NLR) was 0.06 (95% CI: 0.01–0.44) and the area under the curve (AUC) was 0.63 (95% CI: 0.60–0.67). In the validation set, sensitivity and specificity were 96.7% (95% CI: 88.7–99.6) and 39.2% (95% CI: 32.2–46.1), respectively. The NLR was 0.08 (95% CI; 0.02–0.33) and the AUC did not differed from that of the derivation set (0.68 ,95% CI: 0.64–0.72, P = 0.097). Using the Co-LEAD algorithm, 76/250 (30.4%) COVID-19 patients with suspected PE could have been managed without CT pulmonary angiography (CTPA). Conclusion: The Co-LEAD algorithm safely excludes PE, and allows reducing the use of CTPA among COVID-19 patients. Further prospective studies are necessary to validate this strategy.