[1] Natl Ctr Child Hlth & Dev, Div Nephrol & Rheumatol, Tokyo, Japan
[2] Tokyo Metropolitan Childrens Med Ctr, Dept Nephrol, Tokyo, Japan
[3] Natl Ctr Child Hlth & Dev, Dept Pathol, Tokyo, Japan
[4] Tachikawa Hosp, Personnel Mutual Aid Assoc, Federat Natl Serv, Dept Pathol, Tokyo, Japan
[5] Yokohama City Univ, Grad Sch Med, Dept Pediat, Yokohama, Kanagawa, Japan
[6] Univ Ryukyus, Grad Sch Med, Dept Child Hlth & Welf Pediat, Okinawa, Japan
[7] Kobe Univ, Grad Sch Med, Dept Pediat, Kobe, Hyogo, Japan
[8] Toho Univ, Fac Med, Dept Nephrol, Tokyo, Japan
[9] Kitasato Univ, Sch Med, Dept Pediat, Minami Ku, 1-15-1 Kitasato, Sagamihara, Kanagawa 2520374, Japan