1. Division of Infectious Diseases, Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
2. Department of Internal Medicine, Mokpo Hankook Hospital, Mokpo, Jeollanam-do, Republic of Korea
3. Department of Internal Medicine, Presbyterian Medical Center, Jeonju, Jeollabuk-do, Republic of Korea
4. Division of Gastroenterology, Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea