CURRENT KNOWLEDGE ON FUNGAL SPORE ALLERGY

In industrialized countries the prevalence of allergic inhalant diseas es is some 15-20%. More than 10% of these individuals are sensitized t o fungal allergens. Many fungal spores are less than 10 mu m in size, which permits penetration into the smaller airways of the lung. Bronch ial provocation tests have demonstrated that fungal spores and spore e xtracts can cause both an early and a late phase reaction in sensitive subjects. Over 80 genera of fungi have been associated with symptoms of respiratory tract allergy. Ascomycetes, basidiomycetes and zygomyce tes are the major fungal groups that contain genera known to induce an d elicit allergic reactions. These groups contribute most of the spore s found in air. Although ascomycetes include the greatest number of an y fungal group, only a few species, such as Aspergillus fumigatus, Alt ernaria alternata and Cladosporium herbarum, have been investigated in a scientific manner. In recent years spores of basidiomycetes have be en tested for allergenicity and some species have been determined to b e allergenic, such as Calvatia cyathiformis, Ganoderma applanatum, Ple urotus ostreatus, or Psilocybe cubensis. Compared to pollen-related al lergies, diagnosis of fungal allergy is often difficult. Provocative c hallenge with specific fungal antigens can provide a definitive diagno sis. To date, only three controlled immunotherapy trials with standard ized extracts of A. alternata and C. herbarum have shown clinical effi cacy. In spite of these studies, immunotherapy with fungal antigens re quires further investigations. Thus, the indication for immunotherapy with fungal extracts must be judged by an experienced allergist. Apart from pharmacological management, avoiding or minimizing exposure is t he front-line measure.