Keeping up with allergy testing

The Asthma and Allergy Foundation of America states that allergies are among the country’s most common, yet often overlooked, chronic diseases. Allergies affect more than 50 million Americans and are now the third most common chronic disease among children under 18 years old.¹

Awareness of allergy-testing options

Survey results released in July 2009* revealed that 85% of mothers in the United States believe childhood allergies are a serious concern. Yet, when asked about testing their children for allergies, the survey showed that many mothers know little about the testing options available. Allergy-testing methods include blood tests, skin patch tests, skin injection, and the skin prick/scratch test. The survey of over 1,000 U.S. mothers indicated that while most moms (75%) know of the skin prick/scratch test, only one-third to one-half of mothers are familiar with the alternative options.

Of these alternatives, blood tests (in vitro) measure the concentration of allergen-specific IgE (sIgE) in the circulation. Third-generation blood-allergy testing is now available, and physicians are using this convenient and accurate diagnostic tool as a complement to traditional skin-based testing options. Allergy tests play a key role in the diagnosis and management of allergy when used in conjunction with a patient’s history of exposure and physical examination of symptoms.

Advantages of blood testing for allergy include

1. antihistamines, antidepressants, and other drugs which may interfere with skin-testing options do not need to be discontinued in patients undergoing in vitro blood tests. Patients are able to continue taking vital medications without interruption.
2. Third-generation blood tests are highly sensitive and provide a quantitative result.
3. A single blood draw may be used for multiple allergen determinations.
4. The patient is not exposed to the allergen, eliminating the risk of precipitating an allergic response in the patient.

Options for laboratory-based allergy testing include dedicated batch analyzers or a random-access system with an extensive test menu of routine and esoteric immunoassays. In vitro allergy testing delivers tangible value to large-scale, track-based automation laboratory operations as well as to clinics and physician office settings. Technology options include highly automated analytical platforms that incorporate labor-saving efficiencies such as pre-scheduled start up, quality control, and maintenance.

Early diagnosis is critical

Allergy is more than just a seasonal inconvenience. Symptoms like runny nose, watery eyes, coughing, and congestion are not just miserable, they can negatively impact a child’s lifestyle, learning, and health. Allergy is a disease of restriction.
Allergic diseases diminish patients’ quality of life, restrict participation in outdoor sports, decrease on-the-job productivity, and disrupt school performance. Time lost from school may negatively affect grades, academic achievement, self-esteem, and future life successes.²

Parents may be unaware that allergic diseases such as food allergy, rashes (atopic dermatitis) and recurrent ear infections — especially otitis media — can progress to asthma.³  Approximately 40% of infants who have atopic dermatitis may develop asthma by the age of three to four years.⁴ Early identification can facilitate prompt and effective treatment and, therefore, help prevent the progression of allergies to asthma — a disease associated with significant economic costs, health risks, and even morbidity and mortality.^5,6

Accurate diagnosis is key to effective allergy treatment

Effective allergy treatments are available and include antihistamines, desensitizing to inhalant allergens with allergy shots, and avoidance of food or environmental allergens that trigger an allergic reaction.

Medical studies indicate that third-generation allergy blood tests for detecting allergies common in children, including peanuts, insect venoms, milk, foods, dust, and a host of other allergens, may have higher rates of precision, sensitivity, and, in some instances, safety, than other diagnostic options.^7,8

A case study by Grunwald, et al,⁹ demonstrates the potential clinical value of detecting very low levels of sIgE. In this study, a man who had suffered an anaphylactic response to the sting of an unknown insect had a negative skin test for honeybee and wasp venom. Using the third-generation system, this patient was subsequently found to have honeybee venom sIgE present at a concentration of 0.23 kU/L (a level approximately 33% lower than the 0.35 kU/L lowest readable level of sIgE in second-generation systems). He was diagnosed with and successfully treated for honeybee-venom allergy.

Fully automated and quantitative third-generation in vitro sIgE testing is a valuable, reliable tool for allergists, primary-care physicians, and laboratories because it facilitates early accurate diagnosis and appropriate therapeutic interventions with the capacity to serve a large patient population. Early diagnosis makes it possible to practice avoidance and begin treatment that may prevent the progression of allergy to asthma and improve the quality of life for children and adults.

*July 2009 survey was conducted by Siemens Healthcare Diagnostics.

The Walt Disney Company has partnered with a healthcare diagnostics group to introduce a children’s book to the clinical laboratory and physician communities to educate children and parents about the diagnosis and management of allergies. In the book, Mickey and the gang discover that Willie the Giant is allergic to dust, and then learn about simple environmental changes that can ease his symptoms, along with a blood test that helps identify allergy triggers and poses no risk of a severe reaction. By reading a story with familiar Disney characters, children and parents will learn that allergies are common and there are options to help diagnose and manage them.To learn more about allergies, allergy prevention, and treatment options, and to read Mickey and the Giant Kachoo! online, please visit www.siemens.com/kachoo.

Read Mickey and the Giant Kachoo!

Connie Mardis, MEd, is director of Global Marketing Education at Siemens Healthcare Diagnostics and can be reached at [email protected].

References

1. “Chronic Conditions: A Challenge for the 21st Century,” National Academy on an Aging Society, 2000. From the Asthma and Allergy Foundation of America. Allergy Facts and Figures. http://www.aafa.org/display.cfm?id=9&sub=30. Accessed May 1, 2009
2. Lenney W. The burden of pediatric asthma. Pediatr Pulmonol.1997;15:13-16.
3. Yunginger JW, Ahlstedt S, Eggleston PA, et al.Quantitative IgE antibody assays in allergic diseases. J Allergy Clin Immunol. 2000;105:1077-1084.
4. Host A, Andrae S, Charkin S, et al. Allergy testing in children: why, who, when and how? Allergy. 2003;58:559-69.
5. M”oller C, Dreborg S, Ferdousi H, Halken S, et al. Pollen immunotherapy reduces the development of asthma in children with seasonal rhinoconjunctivitis (the PAT-study). J Allergy Clin Immunol. 2002;109:251-256.
6. Clinical Laboratory International. “Allergy: early, accurate diagnosis as a basis for effective treatment.” http://www.cli-online.com/index.php?id=767. Accessed July 1, 2009.
7. Biagini R, MacKenzie B, Sammons B, Smith J, et al. Latex specific IgE: performance characteristics of the IMMULITE 2000 3gAllergy assay compared with skin testing. Ann Allergy Asthma and Immunol. 2006;97:196-202.
8. “Allergy Testing for Children,” Asthma and Allergy Foundation for America Editorial Board, 2005. Asthma and Allergy Foundation for America. http://www.aafa.org/display.cfm?id=9&sub=19&cont=253. Accessed July 15, 2009.
9. Grunwald T, Bockisch B, Spillner E, Ring J, et al. Molecular cloning and expression in insect cells of honeybee venom allergen acid phosphotase (Api m 3). J Allergy Clin Immunol.2006;117:848-854.