Minor Allergens in Moderate-Severe Allergic Rhinitis: Group 4 Mite Amylasa (Blo t4) and Geographical Variations.
Monday, March 5, 2018: 2:15 PM
S310GH (Convention Center)
Ruperto Gonzalez-Perez, MD, PhD, , , ,

Blomia tropicalis is a relevant domestic dust mite in the tropics and subtropics. Several factors may have a direct effect on the allergenicity of mites in different environments and/or periods of the year. As the proposed major allergens of Blomia are Blo t5 and Blo t21, the aim of this preliminary study is to evaluate the sensitization profile of B. tropicalis in patients with moderate-severe allergic rhinitis in our subtropical área.


We selected 21 non-consecutive patients sensitized to B. tropicalis with persistent moderate to severe rhinitis according to the ARIA Guidelines. Skin prick test (SPT) with standarized extracts of B. tropicalis were performed in the forearm followed by immediate reading after 15 minutes. Serum blood samples were obtained from all participating subjects. Total IgE, specific IgE to B. tropicalis and protein allergenic caracterization (SDS PAGE and Western Blot) was performed in all 21 serum samples.


All 21 selected subjects (14 females, 11 to 46 y.o.) showed a positive SPT to B. tropicalis. Interestingly, although different patterns of sensitization to B. tropicalis were obtained, mite amylase Blo t4 was the most frequently found profile (>90%) compared to mayor allergens Blo t5 and Blo t21 in our sample.


Minor group 4 allergens (mite amylase Blo t4) of B. tropicalis may be an important dust mite allergen in moderate to severe allergic rhinitis in certain distinct populations. The reasons for this predominant reactivity to group 4 allergens in some populations is yet to be determined,