1. Department of Respiratory Medicine National Hospital Organization Higashinagoya National Hospital 5‐101 Umemorizaka, Meito‐ku Nagoya Aichi 468‐8620 Japan
2. Department of Infectious Disease Medicine National Hospital Organization Nagoya Medical Center 4‐1‐1 Sannomaru, Naka‐ku Nagoya 460‐0001 Japan
3. Department of Advanced Diagnosis Division of Pathology National Hospital Organization Nagoya Medical Center Nagoya Japan
4. Department of Haematology National Hospital Organization Nagoya Medical Center Nagoya Japan