Other causes include Allograft rejection Amyloidosis Diabetic nephropathy Estrogen therapy Pregnancy Primary hypercoagulability disorders (eg, antithrombin IIIdeficiency, protein C deficiency, protein S deficiency, factor V Leiden mutation, prothrombin G20210A mutation) Renal vasculitis Sickle cell nephropathy Systemic lupus erythematosus Less common causes are related to reduced renal vein blood flow and include malignant renal tumors that extend into the renal veins (typically renal cell carcinoma), extrinsic compression of the renal vein or inferior vena cava (eg, by vascular abnormalities, tumor, retroperitoneal disease, ligation of the inferior vena cava, aortic aneurysm), oral contraceptive use, trauma, dehydration and, rarely, thrombophlebitis migrans and cocaineuse disorder.