[1] Univ Penn, Childrens Hosp Philadelphia, Div Neurol, Philadelphia, PA 19104 USA
[2] Univ Penn, Childrens Hosp Philadelphia, Div Rheumatol, Philadelphia, PA 19104 USA
[3] Univ Penn, Childrens Hosp Philadelphia, Dept Radiol, Philadelphia, PA 19104 USA
[4] Univ Penn, Childrens Hosp Philadelphia, Dept Pathol, Philadelphia, PA 19104 USA