From the Department of General Internal Medicine, Kobe City Medical Center General Hospital, Kobe City, Hyogo, Japan.

The authors declare no conflict of interest.

Informed consent was obtained from the patient.

This work did not receive any specific grants from funding agencies in the public, commercial, or not-for-profit sectors.

Author contributions: D.U. collected the data and wrote the first draft of the manuscript. D.U. and H.N. reviewed the literature. H.N. supervised the manuscript writing, editing, and review.

Correspondence: Hiroaki Nishioka, MD, PhD, Department of General Internal Medicine, Kobe City Medical Center General Hospital, 2-1-1 Minami-Machi, Minatojima, Chuo-ku, Kobe, Hyogo, 650-0047, Japan. E-mail: [email protected].