Ruling Out Acute Deep Vein Thrombosis by ELISA Plasma D-Dimer Assay Versus Ultrasound in Inpatients More Than 70 Years Old

In geriatric care, deep-vein thrombosis (DVT) is mostly diagnosed by noninvasive tech niques. The objectives of this prospective study were: (1) to evaluate the power of ELISA plasma D-dimer assay versus ultrasound (US) in ruling out acute DVT of the lower limbs in symptomatic geriatric inpatients, and (2) to determine the most effective D-dimer cutoff value over the age of 70 years. Over a 10-month period, inpatients with suspected lower limb DVT simultaneously underwent US examination and ELISA plasma D-dimer assay. Noninclusion criteria were comorbid conditions able to modify the D-dimer level. Data were processed by receiver operating characteristic (ROC) curve analysis. In total, 150 patients (125 women, 25 men), average age 86.3 years (range 70-101) were included. A diagnosis of lower limb DVT was established in 53 patients (35.3%). With a 500 ng/mL D-dimer cutoff conventional value, DVT was ruled out in only five patients (3.3%), whereas a 750 ng/mL value ruled out DVT in 19 patients (12.7%) with a...