MPO-ANCA-associated bilateral hearing loss in type 1 diabetes with single positive for insulinoma-associated tyrosine phosphatase-like protein-2 (IA-2) antibody

We report a case of ANCA-associated vasculitis associated with hearing loss in a person with type 1 diabetes. An 81-year-old Japanese woman diagnosed two years earlier with type 1 diabetes with high titer IA-2 antibodies was hospitalized for tinnitus and severe bilateral hearing loss. Despite being treated for acute otitis media and mastoiditis, her symptoms worsened and she developed fever, general fatigue, and appetite loss. Autoimmune screening tests raised the possible involvement of vasculitis associated with antineutrophil cytoplasmic antibody (ANCA) because (1) plasma antimyeloperoxydase (MPO)-ANCA was significantly elevated, and (2) treatment with glucocorticoid markedly relieved symptoms and significantly reduced MPO-ANCA. Her human leukocyte antigen (HLA) genotypes were DRB1*0901, susceptible to type 1 diabetes and frequent for MPO-ANCA-associated vasculitis in Japan. Our case may indicate that ANCAassociated vasculitis should be considered a possible cause of hearing disorder when developing in those with type 1 diabetes.