Absent Inferior Vena Cava with Recurrent Deep Venous Thrombosis

Abstract

Introduction: A congenitally absent inferior vena cava (IVC) is a rare condition that is recognized to be associated with deep venous thrombosis (DVT), especially in young adults. It may be not apparent until later in life.Case presentation: a previously healthy 24 years old male presented with left leg swelling and pain during walking, two years ago. During this admission he was investigated and diagnosed as absent IVC. He developed same manifestation but this time of the right side one year later.Conclusion: patients with congenital IVC anomalies associated with DVT are significantly younger in comparison to patients with isolated DVT of the lower limbs.ultrasonography of the lower limbs diagnosis of DVT was made in which thrombosis extended from left common iliac vein, external iliac vein, internal iliac vein, common femoral vein, popliteal vein, great saphenous vein and small saphenous vein. Contrast enhanced CT of abdomen and pelvis (Figure 1a and 1b) revealed absent IVC, blood drained from iliac veins through lumber veins to Azygos vein and from it to superior vena cava. Associated with superficial subcutaneous collateral formations mostly on the right side and sever varicose vein formations in the abdomen, both in peritoneal and retroperitoneal areas.The patient was admitted to hospital, treated by low molecular weight heparin [enoxaparin] and oral anticoagulation (warfarin). Warfarin was continued for 6 months and international normalized ratio (INR) maintained between 2-3. At the end of the treatment the patient still had mild ankle edema and almost complete venous recanalization, confirmed by Doppler ultrasonography.Investigations to exclude thrombophilia were performed by dosing antithrombin, homocysteine, protein C and S, factor V of leiden and prothrombin mutation, the results all were negative. The patient denied any previous history of thrombosis. There was no family history of thrombosis.Six months after stopping the anticoagulation the patient developed DVT for the second time but this time of the right side. Doppler ultrasonography of the right lower limb show thrombosis extended from right common iliac vein, internal iliac vein, external iliac vein common femoral and popliteal vein. Because of the recurrence of thrombosis for the second time so the decision to continue oral anticoagulation for life was made. DiscussionAbnormalities of IVC and its tributaries are rare [1,2,4,8].Different types of these abnormalities were recorded, to date reached 15 types, and the most common ones are double IVC, complete agenesis of the IVC, left IVC and Azygos continuation [1,4,7,9]. IntroductionDeep venous thrombosis (DVT) is relevant because of its high frequency and morbidity/ mortality rates. Its prevalence in the western population is estimated to be 1:1,000 individuals per year [1][2][3]. The prevalence varies according to age, being 10 times lower in 20-40 years old individuals than in older age groups [2,3].In young patients, its etiology is frequently associated with risk factors like congen...