1. Department of Endocrinology, Metabolism, Rheumatology and Nephrology, Faculty of Medicine, Oita University, Yufu City, Oita, Japan
2. Department of Rheumatology, National Hospital Organization, Beppu Medical Center, Beppu City, Oita, Japan
3. Department of Rheumatology, Oita Red Cross Hospital, Oita City, Oita, Japan