Marco Silva1, Hélder Cardoso2, Guilherme Macedo2. 1. Department of Gastroenterology, Centro Hospitalar São João, Faculty of Medicine of the University of Porto, Alameda Professor Hernâni Monteiro, 4200-319, Porto, Portugal. marcocostasilva87@gmail.com. 2. Department of Gastroenterology, Centro Hospitalar São João, Faculty of Medicine of the University of Porto, Alameda Professor Hernâni Monteiro, 4200-319, Porto, Portugal.