1 Department of Pediatrics, Kawasaki Municipal Hospital, Kanagawa, Japan; Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan.
2 Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan; Department of Pediatrics, Tochigi Medical Center, Tochigi, Japan.
3 Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan.
4 Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan; Department of Pediatrics, Keiyu Hospital, Kanagawa, Japan.
5 Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan; Department of Pediatrics, Saitama City Hospital, Saitama, Japan. Electronic address: yuki0820@trust.ocn.ne.jp.
6 Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan; Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development, Tokyo, Japan. Electronic address: morita-hi@ncchd.go.jp.