Professor of Pediatrics and Medicine, Georgetown University School of Medicine, Department of Pediatrics, Washington, DC.

Dr. Brook has disclosed that he has no significant relationship with or financial interests in any commercial companies that pertain to this educational activity.

Address correspondence and reprint requests to Itzhak Brook, MD, MSc, 4431 Albemarle Street, NW, Washington, DC 20016. E-mail: [email protected].