Congenital abnormalities of the inferior vena cava presenting clinically in adolescent males.

INTRODUCTION Congenital anatomic abnormality of the inferior vena cava (IVC) is an important risk factor for the development of spontaneous proximal lower extremity deep vein thrombosis (DVT) in young adults. The incidence of DVT associated with congenital IVC anomalies in paediatric populations has not been described, and the implications of IVC anomalies for treatment and outcomes of DVT are unknown. METHODS This study reports a series of five adolescent males with spontaneous lower extremity DVTs and underlying congenital IVC abnormalities. Cases were identified by searching the institutional database of patients treated with anticoagulation for venous thromboembolism at a tertiary children's hospital. RESULTS The demographics, clinical presentations, imaging findings, treatment courses, and outcomes are described. All cases occurred in males, and accounted for approximately twenty percent of adolescent males presenting with DVT. CONCLUSIONS IVC abnormality is likely an under-recognized risk factor for DVT in this age group, and detailed vascular imaging should be pursued in adolescents with spontaneous proximal lower extremity DVT when initial ultrasonography does not delineate the proximal clot extent. Management requires individual risk-benefit assessment in the context of providing developmentally appropriate care. Further research is required to establish long-term outcomes and determine optimal treatment strategies.