1 Division of Infectious Diseases, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA. Electronic address: akalil@unmc.edu.
2 Department of Internal Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Infectious Diseases Service, Hospital Moinhos de Vento, Porto Alegre, Brazil; Infectious Diseases Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.