May-Thurner Syndrome

A 14-year-old girl with systemic lupus erythematosus (SLE) was evaluated for worsening left leg pain of 1 week’s duration. A month earlier, she had presented with left knee arthritis and a vasculitic rash; the antinuclear antibody titer was positive. In addition, she had leukopenia, myositis, hypocomplementemia, and mild proteinuria.