1. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea
2. Department of Microbiology, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea
3. Department of Laboratory Medicine, School of Medicine, Pusan National University, Busan, Korea
4. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, School of Medicine, Pusan National University, Busan, Korea