Sensitivity to fungal allergens is a risk factor for life-threatening asthma.

Background: Previous studies have suggested that sensitivity to Alternaria and Cladosporium may be risk factors for life-threatening asthma. We have investigated this by studying the relationship between skin tests for fungal spores and admission to an intensive care unit (ICU) for asthma.

Methods: Skin prick tests for fungal spores (Alternaria tenuis, Cladosporium cladosporoides, Helminthosporium maydis, and Epicoccum nigrum), cat dander, house-dust mite (Dermatophagoides pteronyssinus), and a seven-grass mix were performed in three groups of patients: patients admitted to an ICU with an attack of asthma; those who had received emergency treatment for asthma but had not been admitted to an ICU, and those who had never required emergency treatment for their asthma.

Results: Twenty of 37 patients (54%) admitted to the ICU had a positive skin test for one or more fungal allergens compared with 15/50 patients (30%) in each of the other groups (P=0.005). The ICU patients were no more likely to have positive skin tests for the grass mix, cat dander, or house-dust mite than the other patients.

Conclusions: A positive skin test for fungal allergens is a risk factor for admission to an ICU with an acute attack of asthma.