Whole-blood immunoassay (SimpliRED) versus plasma immunoassay (NycoCard) for the diagnosis of clinically suspected deep vein thrombosis.
BACKGROUND
The level of D-dimer in the blood reflects the level of lysed, cross-linked fibrin, and is a useful diagnostic marker in patients with clinically suspected deep vein thrombosis (DVT). In this study, two assays for the measurement of D-dimer levels were compared: the new, whole-blood immunoassay, SimpliRED, which can be performed at the patient's bedside in two minutes; and the plasma immunoassay, NycoCard.


METHODS
D-dimer levels were determined using these two techniques in 108 patients with clinically suspected DVT. To ascertain or rule out the diagnosis of DVT compression ultrasonography using a colour coded Duplex instrument was done. 8 doubtful cases were diagnosed by ascending phlebography. By these procedures DVT was confirmed in 33 patients and ruled out in the remaining 75 cases.


RESULTS
The SimpliRED assay exhibited a sensitivity of 1.0 (CI 0.89-1.0) and a specificity of 0.75 (CI 0.63-0.84); negative predictive value 1.0 (CI 0.94-1.0), positive predictive value 0.63 (CI 0.49-1.0). By contrast, the NycoCard assay displayed a sensitivity of 0.85 (CI 0.68-0.95) and a specificity of 0.65 (CI 0.53-0.76); negative predictive value 0.91 (CI 0.80-0.97), positive predictive value of 0.52 (CI 0.38-0.66).


CONCLUSIONS
The results show that the SimpliRED assay is a valuable tool in the diagnosis of clinically suspected DVT, especially when laboratory facilities are not accessible.
Mayer
W
W
Department of Dermatology, Wilhelminenspital, Vienna.
Hirschwehr
R
R
Hippmann
G
G
Odpadlik
H
H
Bayer
P
P
Partsch
H
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010991:Plethysmography / Q000295:instrumentation; D019095:Point-of-Care Systems; D011237:Predictive Value of Tests; D013924:Thrombophlebitis / Q000097:blood / Q000175:diagnosis*; D018615:Ultrasonography, Doppler, Color / Q000295:instrumentation
D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D