[1] Univ Buenos Aires, Jose de San Martin Hosp, Div Pulm, Dept Med,Dept A, Arenales 2557,Piso 1, RA-1425 Buenos Aires, DF, Argentina
[2] Univ Guadalajara, Hosp Civil Guadalajara Fray Antonio Alcalde, Guadalajara, Jalisco, Mexico
[3] Univ Guadalajara, Inst Infect & Expt Pathol, Univ Ctr Hlth Sci, Guadalajara, Jalisco, Mexico
[4] Clin Renaca, Vina Del Mar, Chile
[5] Caracas & Vargas Hosp Caracas, Private Hosp Med Ctr, Caracas, Venezuela