FOURTH EDITION Editors Robert Wyllie, MD Calabrese Chair and Professor, Lerner College of Medicine Chair, Pediatric Institute Physician-in-Chief, Children’s Hospital Cleveland Clinic Vice Chair, Office of Professional Staff Affairs Cleveland Clinic Cleveland, Ohio Jeffrey S. Hyams, MD Head, Division of Digestive Diseases and Nutrition Connecticut Children’s Medical Center Hartford, Connecticut Professor, Department of Pediatrics University of Connecticut School of Medicine Farmington, Connecticut Associate Editor Marsha Kay, MD Director, Pediatric Endoscopy Department of Pediatric Gastroenterology and Nutrition Children’s Hospital Cleveland Clinic Cleveland, Ohio 1600 John F. Kennedy Blvd. Ste 1800 Philadelphia, PA 19103-2899 PEDIATRIC GASTROINTESTINAL AND LIVER DISEASE, FOURTH EDITION  ISBN: 978-1-4377-0774-8 Copyright © 2011, 2006, 1999, 1993 by Saunders, an imprint of Elsevier Inc. 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Library of Congress Cataloging-in-Publication Data Pediatric gastrointestinal and liver disease/editors, Robert Wyllie, Jeffrey S. Hyams;  associate editor Marsha Kay.—4th ed.     p. ; cm.   Includes bibliographical references and index.   ISBN 978-1-4377-0774-8 (hardcover : alk. paper)  1.  Pediatric gastroenterology. 2.    Gastrointestinal  system—Diseases.  I. Wyllie, R. (Robert) II. Hyams, Jeffrey S. III. Kay,  Marsha.   [DNLM: 1.  Digestive System Diseases. 2.  Adolescent. 3.  Child. 4.  Infant.  WS 310]   RJ446.P44 2011   618.92'33—dc22 Acquisitions Editor: Kate Dimock Developmental Editor: Taylor Ball Publishing Services Manager: Patricia Tannian Team Manager: Radhika Pallamparthy Project Managers: Claire Kramer, Jayavel Radhakrishnan Designer: Ellen Zanolle Printed in the United States of America Last digit is the print number: 9  8  7  6  5  4  3  2  1 To my dance partner and wife, Dr. Elaine Wyllie. RW To Eli, Alexander, and Debra. JH To my family and dear friends. MK Contributors H. Hesham A-Kader, MD, MSc Salvatore Auricchio, MD Professor of Pediatrics Professor of Pediatrics Chief, Division of Gastroenterology, Hepatology,   Department of Pediatrics and Nutrition Faculty of Medicine and Surgery Department of Pediatrics Universita Degli Studi Di Napoli Federico II University of Arizona Naples Tucson, Arizona ITALY USA Robert D. Baker, MD, PhD Sabina Ali, MD Professor of Pediatrics Pediatric Gastroenterology State University of New York at Buffalo Children’s Hospital and Research Center Oakland Buffalo, New York Oakland, California USA USA Susan S. Baker, MD, PhD Naim Alkhouri, MD Professor of Pediatrics Staff Physician Digestive Diseases and Nutrition Center Pediatric Gastroenterology, Hepatology and Nutrition State University of New York at Buffalo Cleveland Clinic Buffalo, New York Cleveland, Ohio USA USA Todd H. Baron, MD Estella M. Alonso, MD Professor of Medicine Professor of Pediatrics Division of Gastroenterology and Hepatology Northwestern University Mayo Clinic Feinberg School of Medicine Rochester, Minnesota Siragusa Transplant Center USA Children’s Memorial Hospital Chicago, Illinois Brad Barth, MD, MPH USA Assistant Professor Department of Pediatrics Rana Ammoury, MD University of Texas Southwestern Medical School Assistant Professor of Pediatrics Dallas, Texas Division of Pediatric Gastroenterology, Hepatology,   USA and Nutrition The University of Arizona Health Sciences Center Dorsey M. Bass, MD Tucson, Arizona Associate Professor USA Department of Pediatrics Stanford University School of Medicine Marjorie J. Arca, MD Stanford, California Associate Professor of Surgery and Pediatrics USA Divisions of Pediatric Surgery and Pediatric Critical Care Medical College of Wisconsin Phyllis R. Bishop, MD Children’s Hospital of Wisconsin Professor of Pediatrics Milwaukee, Wisconsin Division of Pediatric Gastroenterology USA University of Mississippi Medical Center Jackson, Mississippi Arthur B. Atlas, MD USA Director Respiratory Center for Children Samra S. Blanchard, MD Goryeb Children’s Hospital  Associate Professor Atlantic Health  University of Maryland Morristown, New Jersey  School of Medicine Assistant Professor University of Maryland Medical Center Deptartment of  Pediatrics Baltimore, Maryland University of Medicine and Dentistry (UMDNJ) USA Newark, New Jersey USA vii viii CONTRIBUTORS Athos Bousvaros, MD, MPH Louisa W. Chiu, MD Associate Professor of Pediatrics General Surgery Resident Harvard Medical School Department of General Surgery Associate Director Cleveland Clinic Inflammatory Bowel Disease Center Cleveland, Ohio Children’s Hospital USA Boston, Massachusetts USA Dennis L. Christie, MD Professor of Pediatrics John T. Boyle, MD University of Washington Attending Physician Head Pediatric Gastroenterology, Hepatology, and Nutrition Division of Pediatric Gastroenterology Children’s Hospital of Philadelphia Children’s Regional Hospital and Medical Center Academic Clinical Professor of Pediatrics Seattle, Washington Department of Pediatrics USA The University of Pennsylvania School of Medicine Philadelphia, Pennsylvania Gail M. Cohen, MD, MS USA Assistant Professor of Pediatrics Wake Forest University School of Medicine Steven W. Bruch, MD, MSc Winston-Salem, North Carolina Clinical Assistant Professor USA Department of Pediatric Surgery C.S. Mott Children’s Hospital Mitchell B. Cohen, MD University of Michigan Professor and Vice-Chair of Pediatrics  Ann Arbor, Michigan  Director, Gastroenterology, Hepatology, and Nutrition USA Department of Pediatrics Cincinnati Children’s Hospital Medical Center Brendan T. Campbell, MD, MPH Cincinnati, Ohio Assistant Professor of Surgery USA Department of Pediatric Surgery Connecticut Children’s Medical Center Stanley A. Cohen, MD University of Connecticut School of Medicine Pediatric Gastroenterologist Hartford, Connecticut Children’s Center for Digestive Health Care USA Children’s Healthcare of Atlanta Adjunct Clinical Professor of Pediatrics Anthony Capizzani, MD Emory University School of Medicine Lecturer Atlanta, Georgia Department of Surgery USA University of Michigan Ann Arbor, Michigan Claudia Conkin, MS, RD, LD USA Director, Food and Nutrition Services Texas Children’s Hospital Christine Carter-Kent, MD Houston, Texas Clinical Assistant Professor of Pediatrics USA Associate Staff Physician Pediatric Gastroenterology and Nutrition Arnold G. Coran, MD, AB Pediatric Institute and Children’s Hospital Professor of Pediatric Surgery Cleveland Clinic Section of Pediatric Surgery Cleveland, Ohio University of Michigan Medical School USA Ann Arbor, Michigan  USA Michael G. Caty, MD John E. Fisher Professor of Pediatric Surgery Laura L. Cushman, BS, MS Surgeon-in-Chief Research Associate Department of Pediatric Surgical Services Division of Pediatric Clinical Research Women and Children’s Hospital of Buffalo University of Miami Professor of Surgery and Pediatrics Miami, Florida Department of Surgery USA State University of New York at Buffalo Buffalo, New York USA CONTRIBUTORS ix Steven J. Czinn, MD Mounif El-Youssef, MD Professor and Chair Associate Professor of Pediatrics Department of Pediatrics Mayo College of Medicine University of Maryland School of Medicine Consultant Baltimore, Maryland Gastroenterology and Hepatology USA Department of Pediatrics Mayo Clinic David Devadason, MB, BS, MRCP(UK) Rochester, Minnesota Paediatric Gastroenterologist and Honorary Senior Lecturer USA Paediatric Gastroenterology, Hepatology, and Nutrition Royal Hospital for Sick Children, Edinburgh University Karan McBride Emerick, MD, MSCI Edinburgh Associate Professor of Pediatrics UK Department of Pediatrics University of Connecticut School of Medicine Carlo Di Lorenzo, MD Farmington, Connecticut Professor of Clinical Pediatrics Director of the Liver Disease Center The Ohio State University Division of Digestive Disease and Nutrition Chief, Division of Pediatric Gastroenterology Connecticut Children’s Medical Center Nationwide Children’s Hospital Hartford, Connecticut Columbus, Ohio USA USA Jonathan Evans, MD Ranjan Dohil, MBBCh, MRCP(UK), MRCPCH, DCH(UK) Attending Physician Professor of Pediatrics Division of Pediatric Gastroenterology and Nutrition University of California and Rady Children’s Hospital   Nemours Children’s Clinic and Health Center Jacksonville, Florida San Diego, California USA USA Rima Fawaz, MD Maryanne L. Dokler, MD Instructor in Pediatrics Pediatric Surgeon Division of Pediatric Gastroenterology and Nutrition Nemours Children’s Clinic Children’s Hospital Boston Courtesy Associate Professor Harvard Medical School University of Florida/College of Medicine Boston, Massachusetts Jacksonville, Florida USA USA Ariel E. Feldstein, MD Marla Dubinsky, MD Department of Pediatric Gastroenterology and Nutrition Associate Professor of Pediatrics Cleveland Clinic Cedars-Sinai Medical Center Cleveland, Ohio Los Angeles, California USA USA Laura S. Finn, MD Bijan Eghtesad, MD Associate Professor Staff Surgeon Department of Pathology Department of Hepato-Pancreato-Biliary/Liver Transplant  University of Washington Surgery Seattle Children’s Hospital Cleveland Clinic  Seattle, Washington Cleveland, Ohio USA USA Douglas S. Fishman, MD Peter F. Ehrlich, MD, MSC Director of Gastrointestinal Endoscopy Associate Professor Texas Children’s Hospital Department of Pediatric Surgery Assistant Professor of Pediatrics University of Michigan  Baylor College of Medicine C.S. Mott Children’s Hospital Houston, Texas Ann Arbor, Michigan USA USA