Kara H, Bayir A, Degirmenci S, Kayis S A, Akinci M, Ak A, Celik B, Dogru A, Ozturk B
Acta Clin Belg. 2014 Aug;69(4):240-5. doi: 10.1179/2295333714Y.0000000029.
The D-dimer level, fibrinogen level, and D-dimer/fibrinogen ratio are used in the diagnosis of pulmonary embolism, but results vary. We evaluated these parameters in the diagnosis of pulmonary embolism in emergency clinic patients.
In this prospective study, 200 patients (pulmonary embolism, 100 patients; no pulmonary embolism, 100 patients) had D-dimer and fibrinogen levels measured before intervention. Pulmonary embolism was diagnosed with computed tomography angiography or ventilation-perfusion scintigraphy.
Compared with patients who did not have pulmonary embolism, patients who had pulmonary embolism had significantly greater mean D-dimer level (pulmonary embolism, 6±7 μg/ml; no pulmonary embolism, 1±1 μg/ml; P⩽0·001) and D-dimer/fibrinogen ratio (pulmonary embolism, 3±3; no pulmonary embolism, 0·4±0·4; P⩽0·001), but similar mean fibrinogen levels (pulmonary embolism, 337±184 mg/dl; no pulmonary embolism, 384±200 mg/dl; not significant). In patients who had pulmonary embolism, mean D-dimer level and D-dimer/fibrinogen ratio were greater in high-risk than non-high-risk patients. With D-dimer cutoff 0·35 μg/ml, sensitivity was high (100%) and specificity was low (27%) for pulmonary embolism. With D-dimer/fibrinogen ratio cutoff 0·13, sensitivity was high (100%) and specificity was low (37%) for pulmonary embolism.
A D-dimer level <0·35 μg/ml may exclude the diagnosis of pulmonary embolism. At a D-dimer cutoff 0·5 μg/ml and D-dimer/fibrinogen ratio cutoff 1·0, the D-dimer/fibrinogen ratio may have better specificity than D-dimer level in the diagnosis of pulmonary embolism, but the D-dimer/fibrinogen ratio may lack sufficient specificity in screening.
D-二聚体水平、纤维蛋白原水平及D-二聚体/纤维蛋白原比值用于肺栓塞的诊断，但结果存在差异。我们对这些参数在急诊门诊患者肺栓塞诊断中的应用进行了评估。
在这项前瞻性研究中，200例患者（肺栓塞患者100例；无肺栓塞患者100例）在干预前检测了D-二聚体和纤维蛋白原水平。通过计算机断层扫描血管造影或通气-灌注闪烁扫描诊断肺栓塞。
与无肺栓塞的患者相比，肺栓塞患者的平均D-二聚体水平（肺栓塞患者为6±7μg/ml；无肺栓塞患者为1±1μg/ml；P⩽0.001）和D-二聚体/纤维蛋白原比值（肺栓塞患者为3±3；无肺栓塞患者为0.4±0.4；P⩽0.001）显著更高，但平均纤维蛋白原水平相似（肺栓塞患者为337±184mg/dl；无肺栓塞患者为384±200mg/dl；无显著差异）。在肺栓塞患者中，高风险患者的平均D-二聚体水平和D-二聚体/纤维蛋白原比值高于非高风险患者。以D-二聚体临界值0.35μg/ml时，肺栓塞的敏感性高（100%）但特异性低（27%）。以D-二聚体/纤维蛋白原比值临界值0.13时，肺栓塞的敏感性高（100%）但特异性低（37%）。
D-二聚体水平<0.35μg/ml可排除肺栓塞诊断。在D-二聚体临界值0.5μg/ml和D-二聚体/纤维蛋白原比值临界值1.0时，D-二聚体/纤维蛋白原比值在肺栓塞诊断中可能比D-二聚体水平具有更好的特异性，但D-二聚体/纤维蛋白原比值在筛查中可能缺乏足够的特异性。
