Iliofemoral Deep Vein Thrombosis Despite Repeatedly Negative D-Dimer Results.

A 75-year-old man presented with a three-week history of left lower-limb pain and repeatedly negative D-dimer results. Doppler ultrasonography ultimately revealed extensive iliofemoral deep vein thrombosis (DVT). This case highlights that a negative D-dimer result does not exclude subacute DVT and that clinical suspicion should prevail over biomarker findings.