Association between Mite Allergen (Der p 1, Der f 1, Blo t 5) Levels and Microscopic Identification of Mites or Skin Prick Test Results in Asthmatic Subjects

Abstract

Background: Mite allergens have been involved in airway sensitization and allergic diseases. Immunoassays for the identification and quantifiction of house dust mite (HDM) allergens are useful to improve the knowledge of regional mite fauna and the remediation of mite allergens in allergic diseases. The present study analyzed the association between levels of HDM allergen and results of mite identification or skin prick test (SPT) in two different areas of Bahia, Brazil. Methods: Forty-two asthmatic subjects from a rural area (group I; n = 21) and a slum (group II; n = 21) were evaluated through SPT with HDM allergens and had dust samples collected at their homes for mite identification and allergen measurements. Results: Positive SPT to Dermatophagoides pteronyssinus, Dermatophagoides farinae and Blomia tropicalis allergens were observed in 42.9, 38.0 and 42.9% subjects from group I and in 47.6, 19.0 and 33.3% subjects from group II, respectively. D. pteronyssinus and B. tropicalis were identified in approximately 76 and 50% of samples from both groups, respectively. D. farinae was identified in 38.0 and 9.5% of samples from groups I and II, respectively (p < 0.005). Der p 1, Der f 1 and Blo t 5 detection were associated with mite identification (p < 0.05). Association between HDM allergen levels over 2 µg/g of dust and positive SPT occurred only with D. pteronyssinus (p < 0.0001). Conclusions:D. pteronyssinus was the most prevalent mite species in this study followed by B. tropicalis and D. farinae. Immunoassays done to measure mite allergens were associated with mite-species identification. We conclude that these three mite species must be included on panels for the diagnosis of allergic airway diseases in subjects living in such regions.

Skin reactivity to aeroallergens is reduced in human T‐lymphotropic virus type I‐infected healthy blood‐donors (asymptomatic carriers)

“…Skin reactivity to Der p , Der f and Blo t were the most frequently observed in both groups. This is in accordance with previous observations made by others who have described these mites as the most frequent aeroallergens in our country (21–22).…”

IgE, IgG1, and IgG4 antibody responses to Blomia tropicalis in atopic patients

“…Most AR patients in this study were sensitized to B. tropicalis , with 51% presenting with concurrent sensitization to both B. tropicalis and D. pteronyssinus , and 6% sensitized to B. tropicalis only. This concurrent sensitization has complicated the evaluation of the role of B. tropicalis in these patients, particularly in this geographic region, where both mites have commonly been found (11). However, a substantial group of patients were sensitized to B. tropicalis only, highlighting the need for B. tropicalis ‐hypersensitivity testing and B. tropicalis ‐specific immunotherapy in AR patients with negative SPT to routine inhalant allergens.…”

Conjunctival Provocation Test With Blomia tropicalis

“…Hypersensitivity to Blomia tropicalis is usually based on the results of SPT or serum levels of specific IgE to the whole allergen or to Blo t 5, its major allergen ( 23 – 25 ). Despite the frequent sensitization observed in SPT and S-IgE, Blo t 5 concentration in house dust samples in Brazil ( 26 ) and in other tropical climate countries ( 27 ) have been found to be low with predominance of Dp or other mite species. Another source of discrepancy in this issue could be the existence of different regional variants or isoforms of Blo t 5 that could be underdetected by the ELISA monoclonal assays.…”