Association of aeroallergen sensitization and atopic disease in the Sonoran Desert

Numerous aeroallergens have been associated with the development of asthma, including Alternaria, house-dust mite, and pet dander. Tucson, Arizona, is located in the Sonoran Desert, which has the highest diversity of vegetation of any desert in the world. Given the unique pollen profile in this region, we sought to identify the most common aeroallergens associated with rhinitis and asthma diagnosis in the local adult population.

To identify the prevalence of aeroallergen sensitivity in the Tucson adult population and to identify which aeroallergens are associated with a diagnosis of asthma.

We conducted a retrospective electronic chart review of 226 consecutive adult patients who underwent aeroallergen skin-prick testing for rhinitis at The University of Arizona Adult Allergy and Immunology Clinic over the course of 1 year. All the subjects were tested to a standard panel of tree, grass, weed, mold, house-dust mite, animal dander, cockroach, and feather extracts. Asthma was diagnosed by using the Expert Panel Report 3 guidelines.

Skin testing results were most commonly positive to mesquite (54%), Bermuda (48%), palo verde (47%), olive tree (43%), and chenopodium (43%). Compared with the subjects without asthma, those subjects with asthma were more often sensitized to molds (odds ratio [OR] 2.25 [95% confidence interval {CI}, 1.22-4.14]; p = 0.005), including Alternaria alternata (OR 2.58 [95% CI, 1.23-5.39]; p = 0.011), and cat hair and/or pelt (OR 2.13 [95% CI, 1.24-3.69]; p = 0.006).

Regional pollens contributed significantly to allergic disease in this unique climate. Sensitization to Alternaria and other nonregional aeroallergens were related to asthma, which supported the current practice of testing and treating patients for allergy to both locally significant and ubiquitous aeroallergens.