aUniversity of Colorado, Department of Pediatrics, Division of Rheumatology, Denver, Colorado

bUniversity of North Carolina at Chapel Hill, Department of Pediatrics, Division of Rheumatology

cUniversity of North Carolina at Chapel Hill, Department of Pediatrics, Division of Allergy/Immunology, Chapel Hill, North Carolina, USA

Correspondence to Eveline Y. Wu, MD, MSCR, 030 MacNider Hall, CB #7231, Chapel Hill, NC 27559, USA. Tel: +1 919 962 4496; e-mail: [email protected]