Nebulization: attention to contamination by allergens

Allergens from indoor air may sometimes contaminate nebulizers, with potentially dangerous consequences for children with asthma treated with nebulized aerosol, warn U.S. researchers in the "Annals of Allergy, Asthma & Immunology."

Nebulizers are widely used for the management of asthma treatment for children, remember Mary Bollinger, Faculty of Medicine, University of Maryland, Baltimore, and colleagues. While some doctors refer cases of exacerbation of asthma symptoms after the use of such a device, this phenomenon has rarely been the subject of publications, they continue.

In addition, the causes of these exacerbations are poorly understood. Suggested were the development of airway hyperresponsiveness due to abuse of beta-2 agonist or an adverse reaction to an excipient. A previously published study showed the presence of cockroach allergens in the reservoir of a nebulizer used by a patient who subsequently developed asthma exacerbation threatening his prognosis, say the authors.

To determine whether measurable amounts of allergens can be detected on nebulizers, researchers looked for the presence of major allergens from domestic atmosphere in twenty nebulizers, collected randomly by nurses from the homes of patients to replace equipment as part of a larger study on the use of nebulization with urban youth.

The contents of each reservoir has been analyzed for the presence of cat allergens for, dog, mouse and cockroach. The results of these tests were compared with those made on misters placed in homes with cats or dogs as well as other nebulizers, placed in the same home, but arranged in sealed plastic bags.

Of the 17 reservoirs analyzed among the twenty collected by nurses, five (29%) contained detectable levels of at least one of five allergens tested quantities. In addition, the analysis revealed the presence of measurable amounts of allergens in three of the five tanks misters placed in homes with pets when no allergen was detected in the devices placed in a bag plastic.

These results suggest that the nebulisers may be contaminated with allergens from the atmosphere inside the home, which could have serious consequences for sensitized patients, said the researchers note, however, that the absence of clinical data for patients in this study .

According to them, this type of contamination could be favored by a lack of knowledge on the maintenance of the spray.

Further studies are needed to confirm a possible link between a nebulizer contamination by allergens and the occurrence of asthma exacerbations existence, and to assess the effectiveness of the conservation devices in a sealed plastic bag, say the authors. Must verify whether this storage strategy actually helps protect against contamination of cockroach allergens and does not promote the contrary contamination with other allergens, such as mold, for example, they note.