Mite Fauna Assessment in Houses of Two distinct Socioeconomic Groups From Southern Brazil

Abstract

House dust mites (HDM) are the main source of aeroallergens worldwide, yet epidemiological differences between socioeconomic factors in association with this medical condition have not been studied in the south region of Brazil. To assess the prevalence of HDM in two socioeconomically distinct populations of patients with allergic asthma or rhinitis, the differences between samples from houses of high-income families and low-income families were analyzed. Mite samples were collected between July and December 2015, in Porto Alegre, Brazil. The HDM were Dermatophagoides pteronyssinus and Dermatophagoides farinae (Hughes; Acari: Pyroglyphidae). Also, other non-pyroglyphid house mites were identified in dust samples: Tyrophagus putrescentiae (Schrank; Acari: Acaridae), Chortoglyphus arcuatus, and Cheyletus malaccensis. Identification of species was performed through morphological keys with a stereomicroscope and a phase optical microscope. A total of 104 homes was evaluated (low-income group: n = 53; high-income group, n = 51). We found a total of 721 mites, representing 11 species, in 93 (89%) houses. In the remaining houses, no mites were found. We observed no significant differences of species composition between the groups studied. However, the number of mites was significantly higher in the low-income group (P < 0.001). D. pteronyssinus was the predominant species detected, with 286 mites (39.6%). D. farinae was not detected in any sample. Our results show that living-rooms from low-income families present higher numbers of HDM.

Identification the Cross-Reactive or Species-Specific Allergens of Tyrophagus putrescentiae and Development Molecular Diagnostic Kits for Allergic Diseases

“…The prevalence of T. putrescentiae sensitization in the United States is also very important that there is 34.3% serum sample sensitized both to T. putrescentiae and D. pteronyssinus [ 36 ]. The storage mite T. putrescentiae has often been identified in the house dust samples from South America [ 37 ]. T. putrescentiae is the most prevalent species of storage mite in the dry-stored food products from house and retail stores in Egypt of Africa [ 38 ].…”

IgE, IgG1, and IgG4 Reactivity toDermatophagoides pteronyssinusGlycosylated Extract in Allergic Patients

“…House dust mites (HDM) have been described as important allergen sources causing respiratory allergies, such as asthma and rhinitis, and this association has led to the realization of several studies aiming to elucidate the role of the exposure to these allergens on the synthesis of components of the immune system, including cytokines, such as IL-4, IL-5, and IL-13 as well as different immunoglobulin classes [1]. In prevalence studies, mites from Pyroglyphidae (particularly Dermatophagoides pteronyssinus and Dermatophagoides farinae ) and Echimyopodidae ( Blomia tropicalis ) families have been found in several countries, including areas in Latin America [2–5]. Allergens derived from these mites are characterized according to their biochemical and structural properties in association with the mechanism of IgE induction in the allergic response [6, 7].…”