1 Hamburg Center for Pediatric and Adolescent Rheumatology, Am Schoen Klinik Eilbek, Hamburg, Germany; foeldvari@t-online.de sprechstunde@kinderrheumatologie.de.
2 Children's Pulmonology, Asklepios Klinik Nord - Heidberg, Hamburg, Germany.
3 Pediatric Rheumatology Division, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
4 Department of Pediatrics, Division of Pulmonary Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
5 Hamburg Center for Pediatric and Adolescent Rheumatology, Am Schoen Klinik Eilbek, Hamburg, Germany.