[1] Aichi Med Univ, Div Nephrol & Rheumatol, Dept Internal Med, Nagakute, Aichi 4801195, Japan
[2] Showa Univ, Fujigaoka Hosp, Div Nephrol, Yokohama, Kanagawa 227, Japan
[3] Showa Univ, Fujigaoka Hosp, Div Neurol, Yokohama, Kanagawa 227, Japan
[4] Showa Univ, Fujigaoka Hosp, Dept Med, Yokohama, Kanagawa 227, Japan
[5] Yokohama Sakae Kyosai Hosp, Dept Med, Div Nephrol & Collagen Dis, Yokohama, Kanagawa, Japan