Caval agenesis with a hypoplastic left kidney in a patient with trauma on warfarin for deep vein thrombosis.

Congenital anomalies of the inferior vena cava (IVC) are rare, but recognized, causing deep venous thrombosis. We present a case of a 50-year-old patient with trauma who suffered an intracranial hemorrhage secondary to a fall while on anticoagulation for deep vein thromboses. Venous return from the lower extremities was determined to be through dilated lumbar venous collaterals into the azygous and hemiazygous systems. A second interesting anatomic finding was a hypoplastic left kidney.