1 Department of General Internal Medicine, Hiroshima University Hospital, 1-2-3, Kasumi, Minami-ku, Hiroshima 734-8551, Japan; email: morimiya@hiroshima-u.ac.jp.
2 Department of General Internal Medicine, Hiroshima University Hospital, 1-2-3, Kasumi, Minami-ku, Hiroshima 734-8551, Japan.