Authors: Gerald A. Mandell, MD (DuPont Hospital for Children, Wilmington, DE); Douglas F. Eggli, MD (Pennsylvania State University/Milton S. Hershey Medical Center, Hershey, PA); David L. Gilday, MD (Hospital for Sick Children, Toronto, Ontario, Canada); Sydney Heyman, MD (Children's Hospital of Philadelphia, Philadelphia, PA); Joe C. Leonard, MD (Oklahoma Children's Memorial Hospital, Oklahoma City, OK); John H. Miller, MD (Children's Hospital Los Angeles, Los Angeles, CA); Helen R. Nadel, MD (Children's Hospital, British Columbia, Vancouver, Canada); Amy Piepsz, MD (CHU St. Pierre, Department of Radioisotopes, Brussels, Belgium); and S. Ted Treves, MD (Children's Hospital, Boston, MA)