Atypical painless vision loss in a patient with granulomatosis with polyangiitis

Vasculitis is a common cause of vision loss, and typically painful. In giant cell arteritis, the most common primary vasculitis in adults, we see elevated inflammatory markers, granulomatous inflammation, and associated headache or scalp tenderness. Vision loss caused by granulomatous with polyangiitis (GPA) is rare and typically associated with pain and orbital findings. Our patient presented for shortness of breath and painless vision loss without orbital inflammation or neural enhancement and a normal fundus exam, suggesting posterior ischemic optic neuropathy. Collaboration amongst sub-specialties and obtaining tissue samples are key to diagnosing granulomatosis with polyangiitis to ensure timely treatment of this fatal and blinding disease.