IL4 and Bloom syndrome: Elevated IL-4, IL-13, and IL-17 levels in COPD-BS show Th2 response, which increases blood eosinophil counts and activity and is a potential treatable trait.24 His heightened eosinophilic inflammation correlates with a better response to ICS therapy, potentially reducing exacerbations.9,25 The increase in IL-13 in COPD-BS is consistent with the results obtained by Golpe et al.,12 underscoring its role in allergic inflammation by modulating lymphocyte and myeloid cell responses.