1. Department of ImmunologyUniversity Hospital for Children and YouthHet Wilhelmina Kinderziekenhuis 3584 EA Utrecht The Netherlands
2. Institut für Medizinische Psychologie 45122 Essen Germany
3. Department of Rheumatology and Clinical ImmunologyUniversity Hospital 3584 CX Utrecht The Netherlands
4. Department of Clinical ImmunologyHannover Medical School 36025 Hannover Germany
5. Department of Medical PsychologyHannover Medical School 36025 Hannover Germany