Sjögren syndrome overlapping with ANCA-associated vasculitis: Four additional cases and systematic literature review

Sjögren's syndrome (SS) and ANCA-associated vasculitis (AAV) have distinct clinical presentation and evolution, with paucity of reports on overlap syndrome. We aimed to better characterize this entity.We report four additional cases from the Montpellier university hospital. We also performed a systematic literature review, according to PRISMA guidelines, in Medline, Embase, Web of science, Cochrane Library, and grey literature. Demographic, clinical, and paraclinical data on SS and AAV were analysed.A total of 3133 articles was identified in databases, with 2695 articles screened for eligibility. After exclusion, we had 30 articles on 40 patients to analyse, in addition to 4 patients from our local recruitment (44 patients overall). Patients were female in 81.8%, with median age at AAV onset of 63.5 years. All patients but one presented with SS before, or concomitantly to the diagnosis of AAV, with a median delay of 12 months between both diagnoses. AAV predominantly had renal involvement (35/44 patients, 79.5%), anti-MPO antibodies being the most frequent (35 patients), even in patients presenting with granulomatosis with polyangiitis. We observed significantly more Raynaud phenomenon and associated auto-immune diseases in the group of non-granulomatous AAV (10 patients versus 1, p = 0.015 and 8 patients versus 0, p = 0.013, respectively).This is the largest descriptive study on the association between SS and AAV, providing information on this challenging diagnosis and interplay between these two diseases. Particular attention should be paid in the first months after diagnosis, given the specific complications and outcomes of each disease.