[1] Kangwon Univ Hosp, Dept Hosp Med, Chunchon, South Korea
[2] Yonsei Univ, Dept Internal Med, Wonju Coll Med, Wonju, South Korea
[3] Univ Ulsan, Gangneung Asan Hosp, Dept Pediat, Coll Med, Kangnung, South Korea
[4] Yonsei Univ, Dept Pediat, Wonju Coll Med, Wonju, South Korea
[5] Kangwon Natl Univ, Dept Pediat, Sch Med, Chunchon, South Korea
[6] Kangwon Natl Univ, Dept Internal Med, Div Allergy & Clin Immunol, Sch Med, 1 Gangwondaehak Gil, Chunchon 24341, South Korea