[Prospective study of determining the value of D-dimer in diagnosing pulmonary embolism]

Pulmonary embolism (PE) is still misdiagnosed in a high proportion of cases. 107 patients admitted for suspected pulmonary embolism were studied prospectively to shed light on the value of ELISA-D-dimer and Latex-D-dimer. Pulmonary embolism was ruled out by negative perfusion scans in 66 patients (61.7%) and by angiography in 24 patients. 58% of the scans suggesting a high probability of PE were confirmed by angiography, but only 18% of the scans suggesting a low or intermediate probability of PE. Sensitivity and specificity were 88% and 79%, respectively for the D-dimer ELISA, versus 94% and 90% for the Latex agglutination test. The Latex test increased the positive predictive value of lung scanning suggesting low to intermediate probability of PE (group B) from 18% to 75% and that of lung scanning suggesting high probability of PE (group C) from 58% to 93%. The positive predictive value was improved by ELISA-D-dimer in both groups to 75%. In order to augment the diagnostic efficacy in clinical practice the determination of Latex-D-dimer simultaneously with lung scanning is recommended.