1. From the Division of Pediatric Allergy/Immunology, Johns Hopkins University School of Medicine, Baltimore (J.E.G., E.Y., H.A.S.), and the Division of Clinical Immunology, Mt. Sinai Medical Center, New York (H.M.E.). Address reprint requests to Dr. Sampson at Johns Hopkins Hospital, CMSC 1103, 600 N. Wolfe St., Baltimore, MD 21205.