Extensive Iliocaval Thrombosis as a Presenting Manifestation of Systemic Lupus Erythematosus

A 34-year-old woman presented with a 4-month history of progressive lower-limb swelling and pain with recurrent fever.Examination revealed malar rash, alopecia and polyarticular joint tenderness.Investigations showed anemia, erythrocyte sedimentation rate 120 mm/h, hypoalbuminemia (2.9 g/dL), microscopic hematuria, proteinuria (2.02 g/day) and creatinine 1.35 mg/dL.Antinuclear antibody was strongly positive (1:3200), with marked hypocomplementemia (C3 46.45 mg/dL; C4 <4 mg/dL) and positive anticardiolipin antibodies; anti-double stranded DNA was negative.The clinical and immunological findings were consistent with systemic lupus erythematosus with renal involvement.