TY - JOUR
T1 - Normal D-dimer levels in patients with pulmonary embolism
AU - Kutinsky, Ilana
AU - Blakley, Susan
AU - Roche, Vivyenne
PY - 1999/7/26
Y1 - 1999/7/26
N2 - Background: Pulmonary embolism (PE) is frequently evaluated in acute care settings. Despite this, the clinical diagnosis of PE is difficult. Results of ventilation-perfusion (V/Q) scans may be inconclusive, and pulmonary angiograms (PAGs) are cumbersome, involve risk, and are often unavailable. Using PAG as the standard criterion, we evaluated the relationship between PE, V/Q scans, and semiquantitative latex agglutination (LA) D-dimer levels. Methods: Ninety-eight patients who underwent V/Q scanning for suspected PE were enrolled; based on the results of the scans, the patients were scheduled for PAG. Blood samples were drawn for LA D-dimer assays during the PAGs at Saint Joseph Hospital, Denver, Colo, from January 1, 1996, to February 1, 1997. A detailed medical record review was performed for all enrollees. Results: The mean ± SEM patient age was 56.6 ± 1.9 years; 52 (53%) were men, 13 (13%) had cancer, 23 (23%) had undergone surgery within 30 days of their PAG, and 13 (13%) were receiving warfarin sodium. There were no differences in warfarin therapy, hypercoaguable state, or cancer prevalence between patients with negative and positive PAGs (P = .53). Ventilation-perfusion scan results were available for all study patients. Eight (27%) of 30 patients who had positive angiogram results had LA D-dimer levels less than 250 ng/mL. Patients with positive PAGs (n = 30) had the following V/Q scan results: normal, 0; low probability, 7; intermediate or indeterminate probability, 22; and high probability, 1. In patients with low- probability V/Q scan results (n = 34), a positive D-dimer result for PE (>250 ng/mL) had a sensitivity of 71.4% (95% confidence interval, 0.29-0.97) and a negative predictive value of 87.5% (95% confidence interval, 0.62-0.98). We found a significant difference in D-dimer levels in patients with an abnormal angiogram result (mean, 750 ng/mL) compared with patients with a normal angiogram result (mean, 250 ng/mL) (P = .01, χ2 test). Conclusions: Eight patients had normal D-dimer levels with angiographic evidence of PE. Algorithms in acute care settings have been proposed; they exclude PE with normal D-dimer levels using the enzyme-linked immunosorbent assay technique. These cannot be extrapolated to the more widely used LA assays. A normal LA D-dimer level alone or with V/Q scan results is not recommended to preclude the treatment of PE.
AB - Background: Pulmonary embolism (PE) is frequently evaluated in acute care settings. Despite this, the clinical diagnosis of PE is difficult. Results of ventilation-perfusion (V/Q) scans may be inconclusive, and pulmonary angiograms (PAGs) are cumbersome, involve risk, and are often unavailable. Using PAG as the standard criterion, we evaluated the relationship between PE, V/Q scans, and semiquantitative latex agglutination (LA) D-dimer levels. Methods: Ninety-eight patients who underwent V/Q scanning for suspected PE were enrolled; based on the results of the scans, the patients were scheduled for PAG. Blood samples were drawn for LA D-dimer assays during the PAGs at Saint Joseph Hospital, Denver, Colo, from January 1, 1996, to February 1, 1997. A detailed medical record review was performed for all enrollees. Results: The mean ± SEM patient age was 56.6 ± 1.9 years; 52 (53%) were men, 13 (13%) had cancer, 23 (23%) had undergone surgery within 30 days of their PAG, and 13 (13%) were receiving warfarin sodium. There were no differences in warfarin therapy, hypercoaguable state, or cancer prevalence between patients with negative and positive PAGs (P = .53). Ventilation-perfusion scan results were available for all study patients. Eight (27%) of 30 patients who had positive angiogram results had LA D-dimer levels less than 250 ng/mL. Patients with positive PAGs (n = 30) had the following V/Q scan results: normal, 0; low probability, 7; intermediate or indeterminate probability, 22; and high probability, 1. In patients with low- probability V/Q scan results (n = 34), a positive D-dimer result for PE (>250 ng/mL) had a sensitivity of 71.4% (95% confidence interval, 0.29-0.97) and a negative predictive value of 87.5% (95% confidence interval, 0.62-0.98). We found a significant difference in D-dimer levels in patients with an abnormal angiogram result (mean, 750 ng/mL) compared with patients with a normal angiogram result (mean, 250 ng/mL) (P = .01, χ2 test). Conclusions: Eight patients had normal D-dimer levels with angiographic evidence of PE. Algorithms in acute care settings have been proposed; they exclude PE with normal D-dimer levels using the enzyme-linked immunosorbent assay technique. These cannot be extrapolated to the more widely used LA assays. A normal LA D-dimer level alone or with V/Q scan results is not recommended to preclude the treatment of PE.
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U2 - 10.1001/archinte.159.14.1569
DO - 10.1001/archinte.159.14.1569
M3 - Article
C2 - 10421279
AN - SCOPUS:0033606776
SN - 0003-9926
VL - 159
SP - 1569
EP - 1572
JO - Archives of Internal Medicine
JF - Archives of Internal Medicine
IS - 14
ER -