Background: Agenesis of the inferior vena cava (IVC) as a cause of recurrent deep vein thrombosis (DVT) is uncommon.
Case: A 33-year-old male with no family history of thrombophilia, who had experienced multiple recurrent episodes of DVT over a 15-year period of unknown cause, was admitted into our hospital because of cellulitis in the right leg. Computer tomography with contrast of the abdomen showed an absence of IVC.
Conclusion: Congenital absence of the IVC could be a rare risk factor for idiopathic DVT, especially in young individuals.
Keywords: agenesis; deep vein thrombosis; inferior vena cava.