[1] Univ Hosp Infanta Sofia, Dept Pediat, San Sebastion Reyes, Spain
[2] Univ Europea, Biomed Sch, Madrid, Spain
[3] Univ Hosp Ramon & Cajal, Dept Pediat, Madrid, Spain
[4] Univ Alcala, Med Sch, Madrid, Spain
[5] Univ Hosp La Paz, Pediat Trop & Infect Dis Dept, Madrid, Spain
[6] Univ Hosp Gregorio Maranon, Pediat Infect Dis Unit, Madrid, Spain
[7] Toledo Univ Hosp, Dept Pediat, Toledo, Castilla La Man, Spain
[8] Getafe Univ Hosp, Dept Pediat, Getafe, Spain
[9] Univ Hosp Principe Asturias, Dept Pediat, Madrid, Spain
[10] Univ Hosp Carlos Haya, Dept Pediat, Malaga, Andalucia, Spain
[11] Univ Hosp 12 Octubre, Pediat Infect Dis Unit, Madrid, Spain
[12] Univ Hosp La Paz, Biostat Unit, Madrid, Spain