Diagnostic and therapeutic evaluation of Blomia tropicalis in patients with allergic rhinitis

To assess the clinical relevance of B. tropicalis IgE sensitization through nasal challenge test (NCT) and explore the effectiveness of immunotherapy (AIT) with this mite. A prospective cohort study was conducted in patients with moderate/severe persistent allergic rhinitis. In phase one, atopy tests for B. tropicalis were evaluated using NCT as reference parameter. In phase two, NCT-positive patients underwent AIT for 1 year, followed by a second NCT. Eighty patients sensitized to B. tropicalis were enrolled; 56% had a positive baseline NCT. The SPT and sIgE exhibited a sensitivity over 90%, but a specificity lower than 50% with an overall diagnostic accuracy of 64%. The sIgE to Blo t 5 exhibited a sensitivity of 59.9%, specificity of 80%, and overall diagnostic accuracy 72%. Of those with positive NCT, 39 started AIT. During the second NCT, 82% of these patients tolerated a B. tropicalis extract concentration tenfold higher than baseline. B. tropicalis is clinically relevant for allergic rhinitis patients, but atopy tests for this disease have a low specificity. AIT with B. tropicalis is a therapeutic tool for allergic rhinitis, mainly when a positive-NCT is demonstrated. Allergic rhinitis, a condition that affects the nose can be triggered by a dust mite called Blomia tropicalis. This mite is common in warm and humid environments, particularly in tropical regions. However, it is not yet fully understood how much Blomia tropicalis contributes to allergy symptoms or how effective allergen immunotherapy (a treatment designed to reduce allergic reactions) is when based on this specific mite. In this study, we found that performing a nasal test before beginning immunotherapy is an important step. This test helps confirm whether Blomia tropicalis is truly responsible for the patient’s symptoms. By identifying the actual cause of the allergy, the treatment can be better tailored to each individual, which increases the likelihood of success.