The favorable response to corticosteroids in our patient underscores the importance of recognizing and promptly managing late-onset APES to prevent irreversible lung injury. The robust response to corticosteroids observed in this patient is likely attributable to the active granulomatous inflammation, as evidenced by the biopsy findings of non-caseating granulomas and elevated inflammatory markers (sIL-2R, KL-6), which are known to be steroid responsive. This evidence concerns the gene MUC1 and Granuloma.