1 From the Departments of Pediatrics and Emergency Medicine, Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada (S.B.F.); the Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, the Netherlands (N.C.A.J.K.); and the Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, and the Department of Molecular Microbiology, Washington University School of Medicine, St. Louis (P.I.T.).