Orbital mass in ANCA-associated vasculitides: data on clinical, biological, radiological and histological presentation, therapeutic management, and outcome from 59 patients.

OBJECTIVE: Orbital mass is a rare and sight-threatening manifestation of ANCA-associated vasculitides, which remains a therapeutic challenge. We aimed to describe the presentation, therapeutic management and outcome of ANCA-associated vasculitides-related orbital mass. METHODS: We conducted a French nationwide retrospective study of patients with orbital mass in the setting of ANCA-associated vasculitides according to ACR criteria and/or Chapel Hill Consensus Conference definitions. RESULTS: Fifty-nine patients [33 women, median age 46 (range 7-90) years] were included. Fifty-six (95%) patients had granulomatosis with polyangiitis, two eosinophilic granulomatosis with polyangiitis and one microscopic polyangiitis. Orbital mass was unilateral in 47 (80%) cases, and seemed to develop from ENT involvement in most cases. Orbital mass biopsy was available in 32 (54%) patients, showing lymphoplasmacytic infiltration in 65%, fibrosis in 55%, granulomas in 48% and vasculitis in 36%. All patients but one received glucocorticoids as first-line therapy associated with immunosuppressive agents in 82%, mainly cyclophosphamide. Response to therapy was noted in 52% of patients treated with cyclophosphamide compared with 91% of those treated with rituximab. Twenty-seven (46%) patients required a second-line therapy because of relapse (59%) or refractory course (41%). Sequelae included visual impairment in 28%, with definitive blindness in 17%. Refractory course was associated with PR3-ANCA positivity, visual loss and contiguous pachymeningitis. CONCLUSION: Orbital mass is associated with refractory course and high frequency of sequelae, especially blindness. Refractory course is associated with PR3-ANCA positivity, visual loss and contiguous pachymeningitis.