Which condition is defined by vasculitis, eosinophilia, and asthma?

Churg-Strauss syndrome, known for its association with asthma, eosinophilia, and a systemic vasculitis affecting small to medium-sized blood vessels, is the correct answer. This condition predominantly presents in individuals with a prior history of asthma and allergic rhinitis.

Eosinophilia is a characteristic laboratory finding in Churg-Strauss syndrome, often exceeding 1,500 cells/microL, and is linked to the immune response that occurs in this context. The vasculitis associated with Churg-Strauss can involve multiple organs, and patients frequently present with systemic symptoms such as fever, malaise, and weight loss, in addition to respiratory issues stemming from asthma and possible pulmonary infiltrates.

In contrast, other conditions like polyarteritis nodosa, granulomatosis with polyangiitis, and Takayasu's arteritis do not typically feature the combination of asthma and eosinophilia as central components of their clinical presentation. Polyarteritis nodosa is generally associated with systemic symptoms and renal involvement but lacks eosinophilia and does not specifically correlate with asthma. Granulomatosis with polyangiitis (formerly Wegener's granulomatosis) involves upper and lower respiratory tract symptoms along with