The most common allergens according to skin prick test: The role of wheal diameter in clinical relevancy.

The skin prick test (SPT) could be applied as a useful in vivo method for the detection of sensitization in epidemiological and diagnostic studies if the wheal size is ideally evaluated. We focused on SPT wheal size to identify sensitization pattern to common inhalant and food allergens. In this cross-sectional study, SPT results were obtained from a total of 972 allergic patients. Common allergen extracts for SPT were selected according to the type of allergic diseases, and the geographical pattern. SPT with food allergens was performed for patients with atopic dermatitis (AD) and chronic urticaria (CU). A total of 461 male (47.4%) and 511 female (52.6%) participated in this study (median age: 31 years). The majority of individuals were affected with allergic rhinitis (AR) (n = 624) and asthma (n = 224); while 129 and 67 patients suffered from AD and CU, respectively. The most common aeroallergens were Russian thistle (52.1%) and lamb's quarter (50.7%) with the largest wheal diameter. The wheal size of lamb's quarter was significantly different between patients with asthma and AR (P<.001). In addition, a significant difference was detected in wheal diameter in response to the Russian thistle between patients with AR and AD (P = .001). Shrimp (23.6%) and Peanut (22.5%) caused the most common food sensitization in patients with AD and CU. Having in mind the most common weed pollens including the Russian thistle and lamb's quarter, preventive strategies, such as, removing unwanted weeds or preventing them from growing, avoidance, and specific immunotherapy may be crucial for better disease control.