1. Department of Internal Medicine, Nagaoka Red Cross Hospital , Nagaoka, Niigata , Japan
2. Division of Nephrology, Endocrinology, and Vascular Medicine, Tohoku University Hospital , Sendai, Miyagi , Japan
3. Rheumatology Department and Okinaka Memorial Institute for Medical Research, Toranomon Hospital , Minato-ku, Tokyo , Japan
4. Department of Endocrinology, Metabolism, Nephrology and Rheumatology, Kochi Medical School Hospital, Kochi University , Nankoku-shi, Kochi , Japan
5. Department of Nephrology, Graduate School of Medicine, Kyoto University , Kyoto City, Kyoto , Japan
6. Division of Nephrology and Kidney Center, Kobe University Graduate School of Medicine , Kobe, Hyogo , Japan
7. Department of Pathology, Graduate School of Comprehensive Human Sciences, University of Tsukuba , Tsukuba, Ibaraki , Japan
8. Yamaguchi's Pathology Laboratory , Matsudo, Chiba , Japan
9. Sanko Clinic , Fukuoka, Fukuoka , Japan
10. Medical Corporation, Souseikai , Fukuoka, Fukuoka , Japan
11. Department of Rheumatology, Graduate School of Medical Science, Kanazawa University , Kanazawa, Ishikawa , Japan