[1] Korea Univ, Coll Med, Dept Internal Med, Seoul 136705, South Korea
[2] Univ Ulsan, Coll Med, Div Allergy, Dept Med, Seoul, South Korea
[3] Pochon CHA Univ, Coll Med, Dept Pediat, Songnam, South Korea
[4] Ajou Univ, Sch Med, Dept Allergy & Rheumatol, Suwon 441749, South Korea
[5] Yonsei Univ, Coll Med, Dept Internal Med, Seoul 120752, South Korea