Erratum to: Clin Exp Nephrol DOI 10.1007/s10157-012-0742-z

In the original version of this article, the “Study contributors” was missing in the Acknowledgments and should have been included as follows.

Acknowledgments: This study was supported by a Grant from Astellas Pharm Inc. The authors express their special thanks to Ms. Makiko Nakayama for her assistance.

Study contributors: Yuji Yamaguchi (Japanese Red Cross Sendai Hospital), Katsuya Obara (Tohoku Kosai Hospital), Isao Kurihara (Tohoku Kosai Miyagino Hospital), Yasumichi Kinoshita and Kazuto Sato (Japanese Red Cross Ishinomaki Hospital), Jin Seino (Miyagi National Hospital), Akira Sugiura and Masahiro Miyata (Osaki Citizen Hospital), Kazuhisa Takeuchi (Koujinkai Central Hemodialysis Clinic), Kenji Nakayama and Naoki Akiu (Sendai City Hospital), and Tetsuya Otaka (Katta General Hospital).