1. Division of Hematology, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.
2. Division of Cardiology, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.
3. Division of Gastroenterology, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.
4. Department of Clinical Laboratories, College of Medicine, The Catholic University of Korea, Seoul, Korea.