Atmospheric levels of Alternaria and Cladosporium spores in the city of Beja and their involvement in respiratory allergic disease

Abstract

Introduction – Fungal spores are one of the major biological components of the air but are still poorly studied and their influence on respiratory allergic disease is not recognized. In this work, we intend to determine the importance of the atmospheric spores of Alternaria and Cladosporium in respiratory allergic disease in Beja. Methods – The atmospheric levels of Alternaria and Cladosporium spores in Beja were analyzed. The methodology used and recommended by the Portuguese Aerobiology Network was used: a Hirst volumetric collector, a Burkard seven-day Volumetric Spore-trape^®; the spores were collected on a reel containing a Melinex tape impregnated with silicone and stained with a glycerogelatin solution with basic fuchsin. For the reading of the samples was used the method of reading the four longitudinal lines to the optical microscope with a magnification of 400x. The results obtained were converted and expressed in the number of spores per cubic meter of air. Allergic patients with fungal allergens with positive mx1 allergen sensitization were selected and a molecular diagnosis of allergen sensitization to Alt a1 was performed via the Phadia 250® device by the fluoroenzyme immunoassay method. Results – During the study period, 320,862 Cladosporium spores and 20,741 spores of the Alternaria type were recorded. Molecular diagnostic tests have confirmed that 81% of patients sensitized to fungi are allergic to Alternaria. Conclusion – The atmospheric levels of Alternaria are high and cause allergic sensitization in patients in the Beja region. The Alt a1 allergen allows the identification of most fungal allergic patients in this region.