Background:
Allergy immunotherapy (AIT) with fungal extracts is not as straight forward as that with other inhalants. The complexities relate to the number of airborne fungal spores, the limited data on the exposure to the spores of individual species of fungi and their clinical importance, the poor quality of the fungal
allergen extracts that are available for the diagnosis and treatment, and the lack of controlled studies establishing dosing and efficacy of AIT with fungal extracts except for Alternaria. Objective: The objective was to review what is known with regard to the role of fungi in causing allergic
respiratory diseases as well as the evidence that exists for the role of AIT as a treatment for these conditions. Methods: A search was conducted of PubMed, textbooks, known articles on
immunotherapy with fungal extracts, and references derived from these primary sources. Results: Nine
immunotherapy studies that used Alternaria or its major
allergen Alt a 1 and two studies that used Cladosporium herbarum were identified. When a good quality extract was administered in adequate doses,
immunotherapy with Alternaria was as effective as that with other inhalant
allergens. There was a suggestion of efficacy with a specially prepared Cladosporium extract, but systemic reactions were common and limited the tolerated dose. The use of
immunotherapy as an adjunct treatment for
allergic fungal sinusitis is briefly reviewed, but controlled trials are lacking. Conclusion: Fungal
immunotherapy should largely be limited to Alternaria alternata and perhaps C. herbarum. Under conditions of demonstrated exposure to a particular species of fungus and with symptoms that correlate with that exposure as well as availability of an apparently potent extract of that fungus to which the patient is sensitive that fungus may be considered for
immunotherapy. Fungal (mold) mixes should not be used for diagnosis or
therapy.