House dust mites (HDMs) are the most common of allergies around the world the most common type of dust mites are Dermatophagoides farinae (American house dust mite) and Dermatophagoides pteronyssinus (European house dust mite). The major allergens, Der p 1 and Der p 2 are recognized by more than 90% of HDM-allergic patients, however, 20 other mite allergens have been identified to play a role. Der p 10, with a reported prevalence among D. pteronyssinus sensitized patients to be between 5-18%, has received recent attention as it is a cross-reactive allergen in seafood, and has been described as an important allergen responsible for severe systemic anaphylaxis. Allergen-specific IgE tests that contain the major mite allergens (i.e. Der p 1, Der p 2) and highly cross-reactive mite allergens (e.g. Der p 10) are able to discriminate mite-allergic patients who were mainly sensitized to the major Der p allergens (Der p 1, Der p 2) from patients with a broad sensitization profile.