Systemic vasculitis associated with anti-neutrophil cytoplasmic antibodies against bactericidal/permeability increasing protein.

Myeloperoxidase- and proteinase 3-anti-neutrophil cytoplasmic antibodies (ANCAs) are often negative in cases in which systemic vasculitis is highly suspected. We herein present a case of bactericidal/permeability increasing protein (BPI)-ANCA-positive systemic vasculitis. This case highlights the possible role of BPI-ANCA in the pathogenesis of systemic vasculitis as well as the possible use of BPI as a diagnostic tool. The accumulation of further case-based reports is expected to shed some light on the pathogesis of systemic vasculitis.