1 Department of Pediatric Allergy, National Jewish Hospital and Research Center, 3800 East Colfax Avenue, Denver, Colorado 80206, New York, New York
Dr. Hamburger's letter raises several interesting points. Our statement that an IgE level of 200 IU/ml is "normal" is based on several studies"1-3 using a standardized radioimmunosorbant kit (Phadebas IgE test). These studies indicate that IgE levels in normal, "nonatopic," subjects can be as high as 700 IU/ml with the mean in these populations near 200 IU/ ml.
Dr. Hamburger questions the validity of concluding that our patient was a nonatopic individual. Atopy, as first used by Coca and Cooke in 1923,4 referred to individuals with a hereditary background and personal history of hay fever or asthma.