Article Text
Statistics from Altmetric.com
QUESTION: Can a d-dimer assay, alone or combined with clinical examination results, rule out all, proximal, and calf deep venous thrombosis (DVT) in symptomatic patients?
Design
A blinded comparison of d-dimer test results, either alone or combined with a clinical risk assessment score, with duplex ultrasonographic scanning (DUS).
Setting
A university hospital in London, United Kingdom.
Patients
200 consecutive inpatients and outpatients (mean age 58 y, age range 18 to 91 y, 63% women, 59% inpatients) with suspected DVT. Exclusion criteria were previous or chronic DVT, symptom duration >1 month, anticoagulant therapy >48 hours before assessment, or suspected or confirmed pulmonary embolism.
Description of tests and diagnostic standard
Patients were classified as being at low, moderate, or high risk for DVT based on a clinical assessment score that included data on the presence of cancer, immobilisation, localised tenderness or leg swelling, family history, history of leg trauma, unilateral pitting oedema or erythema, dilated superficial veins, hospitalisation within 6 months, and erythema of symptomatic leg only. d-dimer levels were assessed by using a rapid whole blood assay (SimpliRED, Agen Biomedical, Brisbane, Australia) by an examiner who was blinded to the clinical findings. DUS (diagnostic standard) was done in ablinded manner to identify all, proximal, and calf DVT. Patients with inconclusive scan results had repeated scans done until the diagnosis was conclusive.
Main outcome measures
Sensitivity …
Footnotes
-
Source of funding: none stated.
-
For correspondence: Dr AF Lennox, Irvine Vascular Laboratory, 10th Floor, QEQM Wing, St Mary's Hospital, Praed Street, London W2 1NY, UK. Fax +44 (0)20 7725 6416.