1. Division of Respiratory-Allergy Medicine, Department of Internal Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Korea.
2. Division of Rheumatology, Department of Internal Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Korea.
3. Department of Pathology, Soonchunhyang University Bucheon Hospital, Bucheon, Korea.