[1] Univ Pittsburgh, Childrens Hosp Pittsburgh UPMC, Div Pediat Pulm Med Allergy & Immunol, Pittsburgh, PA USA
[2] Univ Metropolitana, Fdn Hosp Univ Metropolitano, Lab Alergia & Inmunol, Barranquilla, Barranquilla, Colombia
[3] Hosp Aeronaut Cent, Serv Alergia & Inmunol Clin, Div Allergy & Immunol, Buenos Aires, DF, Argentina
[4] Escola Paulista Med, BR-04023 Sao Paulo, Brazil
[5] Lab Invest FEPIS, Quininde, Esmeraldas, Ecuador
[6] St Georges Univ London, Inst Infect & Immun, London, England
[7] Hosp Nacl Ninos Dr Carlos Saenz Herrera, San Jose, Costa Rica
[8] Pontificia Univ Catolica Chile, Sch Med, Dept Pediat, Santiago, Chile
[9] Pontificia Univ Catolica Chile, Sch Med, Dept Publ Hlth, Santiago, Chile