Current in vivo and in vitro screens for inhalant allergy

Screening for inhalant allergy requires the use of a rapid, accurate, cost-effective methodology for the detection of the presence or absence of allergic responsiveness. In vivo and in vitro methods have been demonstrated to be sensitive and specific in the diagnosis of inhalant allergy, even with panels as small as seven or eight antigens. There is good concurrence between skin testing techniques and various serum measures of specific IgE, and both methods can be used effectively for screening inhalant allergy, although per-test costs for in vitro methods remain higher than comparable costs for skin testing [28]. Although the rapidity of both methods is acceptable, skin testing allows immediate observation and interpretation of test results, whereas all in vitro methods involve serum processing that delays results for hours to days. In general, both in vitro methods and epicutaneous testing with a device such as the Multi-Test II offer the clinician effective techniques in screening for inhalant allergy. Each technique has benefit and can be used in both primary care practices and in specialists' offices. The choice of the primary technique to be used for screening depends on the type of practice, the practice's familiarity with skin testing, the geographic region, and the relevant payer mix. A review of the relevant research on allergy screening suggests that the number of antigens used should be in the range of 8 to 12 and should include representative allergens from all the significant classes for the specific geographic [table: see text] region. This screen would probably contain one or two grasses, weeds, and trees, two or three molds, cat allergen, and one dust mite allergen. A sample panel is demonstrated in Box 6. It is important to recognize that the diagnosis and treatment of inhalant allergy is a fluid process. In patients who have negative allergy screens but for whom suspicion of inhalant allergy remains high, additional testing with ID techniques is sometimes indicated. This procedure might be suggested in patients for whom there is a high suspicion of mold allergy or who have unusual inhalant exposures. These individuals may represent a failure of the screening process and require additional testing. In these unusual cases, the judgment of the otolaryngic allergist is critical in guiding this further diagnostic work-up. The use of screening procedures for the diagnosis of inhalant allergy provides a rapid, accurate, and cost-effective method for evaluating patients with a history suggestive of allergic disease. Research suggests that a screening panel has strong clinometric properties and has both sensitivity and specificity in excess of 95%. It is statistically unlikely that a patient with negative findings to an allergy screen will demonstrate clinically significant inhalant allergy.