From the Department of Endocrinology, Metabolism, Nephrology and Rheumatology, Kochi Medical School Hospital, Kochi University, Nankoku, Kochi, Japan.

The authors declare no conflict of interest.

Correspondence: Yoshinori Taniguchi, MD, Department of Endocrinology, Metabolism, Nephrology and Rheumatology, Kochi Medical School Hospital, Kochi University, Kohasu, Oko-cho, Nankoku, Kochi 783-8505, Japan. E-mail: [email protected].