Press Releases: Southern California
July 12, 2004
Test for cat allergies is now more accurate
PASADENA, Calif. – A Kaiser Permanente study published in the Annals of Allergy and Immunology has shown that skin prick testing using a 6-millimeter wheal (a small swelling on the skin that may burn and/or itch indicating an allergic reaction) may be a more effective way of distinguishing individuals with cat allergies than the more widely used three-millimeter wheal which has a tendency to overestimate the presence of cat allergy.
"The skin prick test is the preferred test to determine allergy but the commonly used three-millimeter diameter wheal cutoff for a positive test may not be sensitive enough to adequately detect the allergic state," said Bruce Goldberg, MD, PhD, of the Department of Allergy, Center for Medical Education, Kaiser Permanente Medical Center, Los Angeles, the study's senior author.
"A wheal diameter of three millimeters or larger had been generally accepted as the cutoff for a positive test result although until now, the validity of this assumption had not been rigorously demonstrated," said Goldberg. "Using multiple parameters for assessing allergy to cat including the detection of allergy mediators in mucus following instillation of cat extract directly into the nose of subjects, it was shown that a six-millimeter or greater wheal diameter more closely predicted the presence of cat allergy than the three-millimeter cutoff."
The study was performed on forty-five patients who were referred for evaluation of nasal allergies. Study participants were enrolled at the time of their first visit to their allergist and were excluded if they had a history of acute or chronic sinusitis, anatomic defects of the nose or sinuses, prior allergy shots, or a level of asthma severity requiring daily use of inhaled corticosteroids.
Only patients that were not exposed to cats on a daily basis were tested. The patients were asked to not use antihistamines, topical and oral decongestants for one week and nasal steroids for four weeks.
In addition to Dr. Goldberg, the study's other authors are Maryam Zarei, MD, Candace F. Remer; MD; Michael S. Kaplan, MD; Anne M. Staveren, MD; all of the Department of Allergy, Center for Medical Education, Kaiser Permanente Medical Center, Los Angeles; and Ching-Kow E. Lin, PhD, and Elma Razo, BS, CLS, of the Regional Allergy-Immunology Laboratory, Los Angeles Medical Center, Southern California Kaiser Permanente, Los Angeles.
About Kaiser Permanente
Kaiser Permanente is America's leading integrated health plan. Founded in 1945, it is a nonprofit, group practice prepayment program with Southern California headquarters in Pasadena, California. Kaiser Permanente serves the health care needs of 3.3 million members in Southern California. Today it encompasses the nonprofit Kaiser Foundation Health Plan, Inc., Kaiser Foundation Hospitals and their subsidiaries, and the for-profit Southern California Permanente Medical Group. Kaiser Permanente's Southern California Region includes more than 49,900 technical, administrative and clerical employees and caregivers, and more than 6,000 physicians representing all specialties. More information about Kaiser Permanente can be found at kaiserpermanente.org.
