1 Gastrointestinal Endoscopy Unit, Hospital das Clinicas, University of São Paulo Medical School, Dr. Arnaldo Av, 455, São Paulo, 01246-903, Brazil. vbrunaldi@gmail.com.
2 Gastrointestinal Endoscopy Unit, Hospital das Clinicas, University of São Paulo Medical School, Dr. Arnaldo Av, 455, São Paulo, 01246-903, Brazil.