Allergens may contaminate nebulisers

Indoor allergens can contaminate asthmatic children's nebuliser equipment, with potentially serious consequences for sensitive individuals. Researchers from the University of Maryland School of Medicine in Baltimore, USA, reported two cases of life-threatening asthma episodes in patients who used nebulisers contaminated with cockroach allergen. To investigate if levels of cockroach allergen or other common home allergens can be detected in nebulisers, visiting nurses replaced nebuliser equipment for 20 families participating in an ongoing study of asthma in inner-city children. The equipment that was removed was tested for cat, dog, mouse and cockroach allergens. Samples were adequate for testing allergens in 17 of the nebulisers, and five of these contained measurable levels of at least one of the allergens. The researchers also placed nebuliser reservoirs in the homes of study participants who had cats or dogs as pets. Two of the three in homes with cats were contaminated with cat allergen, and one of the two homes with dogs was contaminated. When the researchers placed reservoirs in sealed plastic bags in the same homes, no allergens were found. This approach appears useful. However, the researchers point out that it is not clear if this storage technique can keep equipment free of cockroach allergen or if the sealed plastic bags will promote the growth of molds or other allergens.