Staphylococcus aureus enterotoxin A- and B-specific IgE in chronic obstructive pulmonary disease

Sensitization to Staphylococcus aureus enterotoxins A (SEA) and B (SEB) has been associated with asthma severity, exacerbations, and disease control. Our study aimed to investigate if there are differences in serum SEA-IgE and SEB-IgE levels between patients with chronic obstructive pulmonary disease (COPD), asthma, and controls, and to assess the association between SE sensitization and COPD clinical parameters and Th2 inflammation biomarkers in two well-defined COPD cohorts. Our findings suggest that COPD patients do not exhibit higher SEA and SEB sensitization compared to asthma patients and controls. However, in COPD patients, the presence of atopy and allergy is associated with positivity for SEA-IgE and SEB-IgE. Consequently, these allergens may aid in identifying atopic or allergic subgroups within the COPD population, but they are not directly associated with the diagnosis of COPD, elevated circulating blood eosinophils, or fractional exhaled nitric oxide (FENO) levels.