Acquired Brown's syndrome associated with hypogammaglobulinemia

We describe a 10-year-old girl with hypogammaglobulinemia who presented initially with painless progressive diplopia on right upward gaze and associated tenderness in the area of the superior oblique tendon (Brown's syndrome). She was given prednisone (40 mg/day) with gradual improvement of her symptoms. Prednisone was tapered and her symptoms remained unchanged for 10 months. She then experienced rapid deterioration. Prednisone was reinstituted with similar improvement and then therapy was switched to naproxen. She remains with only slight diplopia on extreme upward gaze.