The aim of this review is to describe the relationships between allergy and infectious diseases, with specific attention on bacterial infection. According to the most recent literature, bacteria could be considered also as one of the major causes of asthma exacerbations that we need to further explore.
The availability of novel methods to detect large panels of pathogens, including viruses and bacteria specific for the upper respiratory tract, together with the capacity of evaluating how basophils are activated, has changed the point of view of the mechanisms related to asthma exacerbations. The recent finding that basophils are activated in the presence of suboptimal doses of allergens and bacteria has been recently described and may explain the clinical behavior of allergy exacerbation. Indeed the activation of basophils induces the secretion of mediators, which, at bronchial level, may cause bronchospasm that leads to an asthma exacerbation in patients with infection. The contrary is also true.
Although the explanations for these facts are numerous, at present, bacteria seem to play a relevant role in the worsening of asthma in infected patients.
aClinical Pathology Laboratories, Department of Experimental and Laboratory Medicine, Istituto G. Gaslini
bPneumology and Allergy Centre, Department of Internal Medicine, University of Genova, Genova, Italy
cResearch Centre in Respiratory Medicine, Catholic University, Cordoba, Argentina
Correspondence to Giovanni Melioli, MD, Clinical Pathology Laboratories, Department of Experimental and Laboratory Medicine, Giannina Gaslini Teaching Hospital, Genova, Italy. Tel: +39 010 5636557; fax: +39 010 3994168; e-mail: firstname.lastname@example.org