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BackgroundMany patients with eosinophilic granulomatosis with polyangiitis (EGPA) lack a “vasculitic” phenotype and/or are ANCA negative. Recently, the Groupe d’Etudes et de Recherche sur les Maladies Orphelines Pulmonaires developed a revised nomenclature for EGPA and proposed to differentiate it from hypereosinophilic asthma with systemic (nonvasculitic) manifestations (HASM).ObjectivesTo evaluate the occurrence of genuine polyangiitis and HASM in a cohort of patients with EGPA.MethodsWe retrospectively studied the medical records of patients with EGPA that fulfilled the classification criteria of the American College of Rheumatology. Patients with genuine vasculitis were identified by at least one of the following criteria:1 definite vasculitis feature as defined: biopsy-proven necrotizing vasculitis of any organ, biopsy-proven necrotizing glomerulonephritis or crescentic glomerulonephritis, alveolar haemorrhage, palpable purpura, myocardial infarction due to proven coronary arteritis;2 strong surrogate of vasculitis as defined: haematuria associated with red casts or ≥10% dysmorphic erythrocytes, or haematuria and 2+proteinuria on urinalysis related to the systemic disease; and any organ manifestation other than ENT or bronchopulmonary manifestation associated with leukocytoclastic capillaritis and/or eosinophilic infiltration of the arterial wall;3 mononeuritis multiplex;4 ANCA with at least one extra-thoracic non-ENTmanifestation of disease.ResultsWe followed 68 patients with EGPA for a mean ±SD of 6.3±6.5 years (587.7 patient-years). There were 19 males and 49 females. Their mean ±SD age was 49.5±13.8 years. In 18 patients (26.5%) with EGPA diagnosis was revised in favour of HASM using the new criteria (table 1). Notably, 19 of 50 patients (38%) with genuine polyangiitis were ANCA-negative but have histological evidence or clinical signs (rapidly progressive glomerulonephritis in 1, mononeuritis multiplex 7, palpable purpura in 5) of definite vasculitis. The majority of patients in both groups were females of similar age at disease onset. The occurrence of constitutional symptoms, except myalgia, nasal involvement, cardiovascular and pulmonary manifestations did not differ between patients with genuine polyangiitis and HASM. However, patients with EGPA usually required more intensive immunosuppressive treatment, including cyclophosphamide, while monotherapy with moderate to high dose corticosteroids was adequate for the majority of patients with HASM.Table 1 Clinical and demographic characteristics of patients with genuine EGPA and HASMConclusionsAt least a quarter of patients with EGPA classified according to the ACR criteria do not have genuine polyangiitis. The revised criteria of EGPA and HASM may have a significant value for choosing treatment options.Disclosure of InterestNone declared