[1] Fed Univ Hlth Sci Porto Alegre UFCSPA, Dept Paediat, Porto Alegre, Brazil
[2] Hosp Crianca Santo Antonio, Paediat Pulmonol Sect, Porto Alegre, Brazil
[3] Univ Sao Paulo, Hosp Clin, Med Sch USP, Inst Crianca & Adolescente, Sao Paulo, SP, Brazil
[4] Hosp Israelita Albert Einstein, Sao Paulo, SP, Brazil
[5] Pontificia Univ Catolica Chile PUC, Sch Med, Dept Paediat Pulmonol, Santiago, Chile
[6] Fed Univ Rio Grande UFRGS, Sch Med, Dept Paediat, Porto Alegre, Brazil