1. Department of Pediatric Surgery, Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Bayern, Germany
2. Department of Pediatric Gastroenterology, Dr. von Hauner Children's Hospital, University Hospital Munich, LMU Munich, Bayern, Germany
3. Department of Pediatrics, Gastroenterology and Nutrition, School of Medicine Collegium Medicum University of Warmia and Mazury, Olsztyn, Poland