A 45-year-old woman attends with three days of unilateral calf swelling and tenderness after a long-haul flight. Her modified Wells score for deep vein thrombosis is calculated as 0 (DVT unlikely). What is the appropriate next step?

• A Start therapeutic low molecular weight heparin pending imaging
• B Perform proximal leg vein ultrasonography directly
• C Perform contrast venography as the first-line test
• D Measure D-dimer; if normal, deep vein thrombosis is excluded and no imaging is needed ✓

Explanation

In a patient classified as DVT unlikely by the Wells score, a negative quantitative C-dimer safely rules out deep vein thrombosis without imaging, avoiding unnecessary ultrasound. If the C-dimer is elevated, proximal leg vein ultrasonography is then performed. Empiric anticoagulation without confirmation exposes the patient to bleeding risk. Contrast venography remains the historical gold standard but is invasive and reserved for cases where ultrasound is equivocal or technically impossible. This risk-stratified pathway is standard Indian and international practice.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.