1. Department of Internal Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
2. Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
3. Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
4. Department of Pulmonary and Critical Care Medicine, Ajou University Hospital, Ajou University School of Medicine, Suwon, Korea.
5. Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
6. Department of Internal Medicine, Mokdong Hospital, Ewha Womans University School of Medicine, Seoul, Korea.
7. Division of Infectious Diseases, Department of Intermal Medicine, Eulji University College of Medicine, Daejeon, Korea.
8. Department of Internal Medicine, Wonju Christian Hospital, Yonsei University Wonju College of Medicine, Wonju, Korea.
9. Division of Infectious Diseases, Department of Internal Medicine, Anam Hospital, Korea University College of Medicine, Seoul, Korea.
10. Department of Internal Medicine, National Health Insurance Corporation Ilsan Hospital, Goyang, Korea.