2021 Volume 70 Issue 4 Pages 639-646
We examined the D-dimer level in relation with the thrombus site and thrombus stage in 825 patients who underwent both lower extremity vein ultrasonography and D-dimer level determination for the diagnosis of deep vein thrombosis (DVT). DVT was observed in 216 patients (26%). The thrombus sites were of the central type (85) and peripheral type (131), and the thrombus stages were the acute (56) and chronic (160) stages. The median D-dimer levels in the DVT and non-DVT groups were 8.8 μg/mL and 2.1 μg/mL, respectively. In 137 patients with D-dimer levels in the reference range, no DVT was detected. D-dimer levels were 9.8 μg/mL in DVT patients with the central type and 7.6 μg/mL in those with the peripheral type, and 10.0 μg/mL in those in the acute stage and 7.9 μg/mL in those in the chronic stage; these values were not significantly different. When compared between outpatients and inpatients, the acute stage was significantly more prevalent than the chronic stage in outpatients (p = 0.003). Furthermore, when we followed the course of thrombus and D-dimer level, the D-dimer level tended to decrease over time in the group wherein the thrombus stage did not advance. Consequently, we confirmed that the low D-dimer level is useful for excluding the existence of thrombus, and the D-dimer level may be helpful in estimating the thrombus stage in outpatients. Moreover, because of the low specificity of the D-dimer level for the diagnosis of DVT, it will be effective to confirm the time course of the D-dimer level rather than the D-dimer level at one time.
