Jong Hwan Jung1, Seon Ho Ahn2. 1. Division of Nephrology, Department of Internal Medicine, Wonkwang University Hospital, Wonkwang University School of Medicine, Iksan, Korea. 2. Division of Nephrology, Department of Internal Medicine, Wonkwang University Hospital, Wonkwang University School of Medicine, Iksan, Korea. chjh0502@wku.ac.kr.