Dual ANCA positivity in subacute bacterial endocarditis.

Nine cases of subacute bacterial endocarditis (SBE) associated with anti-PR3 ANCA have been described in the literature to date. We describe 2 cases of SBE associated with dual ANCA positivity (anti-PR3 and anti-MPO ANCA.) To our knowledge, these are the first such reported cases. One case was associated with cutaneous vasculitis, and the second with predisposing factors for SBE. ANCA titers resolved or decreased in both during initial corticosteroid therapy for suspected vasculitis. Follow-up of these patients revealed no evidence of the common ANCA associations such as Wegener granulomatosis. Rheumatologists, if aware of ANCA association with SBE, can avoid inappropriate immunosuppressive treatments.