Prospective diagnostic accuracy assessment of the HemosIL HS D-dimer to exclude pulmonary embolism in emergency department patients.
BACKGROUND
Chest pain and shortness of breath are among the most common symptoms requiring immediate evaluation. Testing for pulmonary embolism (PE) has become easier and widespread due to D-dimer blood tests. Safe use of these tests is only possible if sensitivity is high and they are used in non-high probability patients. We evaluated diagnostic performance of the HemosIL HS D-dimer, which despite FDA approval in 2005, has been minimally reported in prospective standard clinical care.


METHODS
We used a prospective observational study design to follow patients in a single center with the HemosIL HS ordered for symptoms of possible PE with positive test result if >243 ng/ml. The outcome was PE or deep venous thrombosis (DVT) at the time of presentation or subsequent 45 days determined by structured evaluation of imaging tests, phone, or medical record follow-up in all patients.


RESULTS
529 patients received a D-dimer and 4.7% were ultimately diagnosed with PE or DVT. The sensitivity of the HemosIL HS was 96.0% (95% CI; 79.6 to 99.9%) specificity was 65.7% (95% CI; 61.4 to 69.8%) and likelihood ratio negative was 0.06 (95% CI; 0.01 to 0.42). The probability of PE in patients with a negative D-dimer was 1/332 or 0.3% (95% CI; 0.01% to 1.67%). The receiver operator curve had an area under the curve of 0.87 and supported the current cut-point as optimal.


CONCLUSIONS
The HemosIL HS D-dimer had high sensitivity, very low negative post-test probability and is useful in excluding PE in the acute care setting.
Courtney
D Mark
DM
Northwestern University, Chicago, IL 60611, United States. mcourtney@nmff.org
Steinberg
Justin M
JM
McCormick
Jennifer C
JC
D000933:Antifibrinolytic Agents; D019540:Area Under Curve; D003937:Diagnosis, Differential; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005338:Fibrin Fibrinogen Degradation Products; D005500:Follow-Up Studies; D006801:Humans; D016013:Likelihood Functions; D011237:Predictive Value of Tests; D011336:Probability; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000175:diagnosis*; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013997:Time Factors; D020246:Venous Thrombosis / Q000175:diagnosis
D000933:Antifibrinolytic Agents; D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D