1. Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.
2. Department of Allergy and Clinical Immunology, Ajou University School of Medicine, Suwon, Korea.
3. Department of Allergy and Clinical Immunology, Dong-A University College of Medicine, Busan, Korea.
4. Department of Allergy and Clinical Immunology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.