[1] Univ Fed Rio Grande Sul UFRGS, Hosp Clin Porto Alegre HCPA, Dept Internal Med, Nephrol Div, Porto Alegre, Brazil
[2] Univ Sao Paulo, Hosp Clin HCFMUSP, Nephrol Div, Sao Paulo, Brazil
[3] Univ Nove Julho UNINOVE, Nephrol Div, Sao Paulo, Brazil
[4] BP Beneficencia Portuguesa, Nephrol Div, Sao Paulo, Brazil
[5] Univ Fed Sao Paulo, Nephrol Div, Sao Paulo, Brazil
[6] Hosp Israelita Albert Einstein, Sao Paulo, Brazil
[7] Amer Hlth Fdn, Washington, DC 20036 USA
[8] Hosp Univ Evangel Mackenzie, Dept Med, Nephrol Div, Curitiba, Brazil