Pamela F Weiss1
, Diana A Corao2
, Avrum N Pollock3
, Terri H Finkel1
and Sabrina E Smith4 
1
Division of Rheumatology, Department of Pediatrics, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
2
Department of Pathology, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
3
Department of Radiology, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
4
Division of Neurology, Department of Pediatrics, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA, USA