A Case of Systemic Lupus Erythematosus without Antiphospholipid Syndrome Causing Superior Vena Cava Syndrome.

Systemic lupus erythematosus (SLE) is an autoimmune disease with multisystem involvement. Superior vena cava (SVC) syndrome is mainly caused by malignant tumors such as lung carcinoma, lymphoma, and metastatic tumors. We report a 20-year-old woman who was admitted with features of SVC syndrome secondary to SVC thrombus. Further evaluation confirmed the diagnosis of SLE without associated antiphospholipid syndrome (APS). The patient was treated with heparin with oral anticoagulant, steroids, and hydroxychloroquine. Complete resolution of thrombus was documented within a few weeks. SVC thrombosis as an initial presenting feature of SLE without associated APS has not been reported so far in the literature.