[Identification of house dust mite fauna from allergic patients' mattress in six Mexican states]

Abstract

Background: House dust is considered an important source of aeroallergens, and the mites living there, are the main cause of allergy to it. In México, there have been few about house dust fauna, and mostly limited to México City.

Objective: To describe the house dust fauna from mattresses of allergic patients from different cities in México.

Methods: Sixty dust samples were collected from mattresses in 6 Mexican states: Oaxaca, Tamaulipas, Veracruz, Puebla, Chiapas and Campeche. Mites were isolated under a stereomicroscope using lactic acid -0.9% NaCI solution. Identification was performed on fixed slides prepared with Hoyer solution. Skin Tests were already performed with allergen extracts of different house dust mites species in the 60 mattress' owners, whom had previously been diagnosed with respiratory allergy.

Results: The Pyroglyphidae family was found in 100% of dust samples. Dermatophagoides pteronyssinus (Dp) and Dermatophagoides farinae (Df) were the species most frequently found (>90%). These findings were in agreement with the skin tests results, where 100% of patients were positive to Dp, whereas 70% was positive to Df. It was evidenced for the first time the presence of Blomia tropicalis in Tamaulipas, Veracruz and Campeche states, and Dermatophagoides siboney in Campeche. Both species are important allergenic sources in tropical/subtropical climates.

Conclusions: These results confirm the importance of Pyroglyphid house dust mites, as indoor sensitizers in different climatic and geographical regions in México, as well as, the relevance of tropical species, particularly Blomia tropicalis and D. Siboney, in certain areas.