Mite sensitization patterns shift in Spain and Portugal, survey of allergists finds

Most allergists surveyed in Spain and Portugal report seeing patients sensitized not only to the classic house dust mites of the genus Dermatophagoides but also to two emerging mite species: Lepidoglyphus destructor and Blomia tropicalis. In a real-world, mixed-methods study known as the MITE-WISE project, published in Frontiers in Allergy, 215 allergists completed an online questionnaire and eight experts took part in semi-structured interviews. The authors report that 97.7% of surveyed specialists managed patients with reported clinically relevant sensitization to Dermatophagoides species together with L. destructor, while 70.7% reported the same for Dermatophagoides species together with B. tropicalis. These figures describe allergist-reported clinical experience rather than measured sensitization rates in the general population.

The eight interviewed experts perceived an increasing recognition of sensitization to both emerging mites, with B. tropicalis highlighted particularly in the Canary Islands and along the Portuguese coast. Dermatophagoides species remain, according to the study’s introduction, the most prevalent mite allergens associated with allergic rhinitis, asthma and atopic dermatitis in Southern Europe, but sensitization to L. destructor and B. tropicalis has been increasingly reported in Iberian regions. The study was motivated by the concern that diagnostic and allergen immunotherapy (AIT) strategies may not reflect this shift in sensitization profiles.

Reported testing practices differed markedly between the two mites. Among the allergists who answered this question, 85.2% (179 of 210) reported always testing for L. destructor, whereas only 36.8% (56 of 152) reported routinely testing for B. tropicalis. The authors describe this as a descriptive difference that may reflect heterogeneous diagnostic practices, and they caution against drawing firm conclusions from it. Testing for B. tropicalis was thus reported considerably less frequently than testing for L. destructor among the participating specialists.

Prescription behaviour followed a similar pattern within the subgroups that routinely tested each mite. Among specialists who reported always testing for L. destructor, 98.9% (177 of 179) reported prescribing AIT targeting both Dermatophagoides species and L. destructor in patients with reported clinically relevant sensitization. Among those who reported routinely testing for B. tropicalis, 91.1% (51 of 56) reported prescribing AIT targeting Dermatophagoides species and B. tropicalis in comparable patients. All respondents reported a preference for subcutaneous AIT, and 98% of AIT prescribers reported using polymerized extract mixtures.

The authors are explicit about the limits of these findings. Because the study recruited allergists experienced with AIT, the reported proportions should not be generalized to all specialists. The questionnaire captured self-reported practice rather than objectively confirmed sensitization or clinical outcomes, and the conclusion notes that whether region-specific inclusion of L. destructor and B. tropicalis in diagnostic protocols would improve diagnosis or treatment outcomes remains to be established in studies with objective confirmation of clinical relevance. The work was received on 23 July 2026 and accepted on 5 October 2026, and the final formatted version is pending publication.

Subject of Research: Real-world diagnostic and allergen immunotherapy practices for mite sensitization in Spain and Portugal

Article Title: Shifting patterns of mite sensitization in Spain and Portugal: real-world diagnostic and immunotherapy practices (MITE-WISE project)

Article References: González-Pérez, R., Antón, M., Rial, M. J., & Figueroa, J. (2026). Shifting patterns of mite sensitization in Spain and Portugal: real-world diagnostic and immunotherapy practices (MITE-WISE project). Frontiers in Allergy, 7, Article 1946434. https://doi.org/10.3389/falgy.2026.1946434

Image Credits: AI Generated

DOI: 10.3389/falgy.2026.1946434

Keywords: house dust mite allergy, Dermatophagoides, Lepidoglyphus destructor, Blomia tropicalis, allergen immunotherapy, sensitization, Spain, Portugal, allergists survey, diagnostic practices, subcutaneous immunotherapy, MITE-WISE