Is it atopic asthma, chronic eosinophilic pneumonia, or eosinophilic granulomatosis with polyangiitis?

A 45-year-old man, used to work in a cement factory, presented to us with a history of adult-onset sub-optimally controlled asthma and was initially managed as a case of acute exacerbation of allergic asthma. However, his repeated evaluation revealed raised eosinophil count, raised serum total IgE and persistent chest infiltrates on imaging. He was provisionally managed empirically with a short course of oral steroids and advised follow-up on an out-patient basis to rule out the possibility of idiopathic eosinophilic pulmonary syndromes. The patient was then lost to follow-up, and after four years, he presented with a vasculitic presentation and was diagnosed with Eosinophilic Granulomatosis with Polyangiitis (EGPA). He improved with corticosteroids and cyclophosphamide pulse therapy. This case depicts the importance of evolving nature of EGPA wherein the eosinophilic phase of the disease can mimic other pulmonary eosinophilic diseases and vasculitic symptoms can be delayed as much as by four years.