Ear, nose, and throat involvement in eosinophilic granulomatosis with polyangiitis.

Eosinophilic granulomatosis with polyangiitis (EGPA) is the rarest of the anti-neutrophil cytoplasm antibody (ANCA)-associated small-vessel vasculitides. In Europe, its prevalence ranges from 10 to 15/million and annual incidence from 0.9 to 1.2/million. EGPA affects men and woman equally, with a mean age of 50 years at diagnosis. The most characteristic features include late-onset asthma, pulmonary infiltrates, mono-or polyneuropathy, and peripheral and extravascular eosinophils. Ear, nose, and throat (ENT) manifestations are particularly frequent, occurring in 30-80% of patients and most often early in the disease process. ENT features include allergic rhinitis, chronic sinusitis and polyposis, lacrimal and salivary gland involvement, otitis media and, rarely, cranial nerve involvement. The diagnosis of EGPA may be relatively straightforward in the 30-40% of ANCA-positive patients and in those with biopsies demonstrating vasculitis, but it can be more challenging, or even debatable, in ANCA-negative patients who do not present clear evidence of vasculitis. Because EGPA is a multisystem disease, it requires a multidisciplinary approach for diagnosis and management, including by an otolaryngologist. [ABSTRACT FROM AUTHOR]