PRTN3 and granulomatosis with polyangiitis: A 73-year-old man (body weight, 72.2 kg; height, 158 cm) had been diagnosed with GPA 20 years previously based on optic narrowing, upper respiratory symptoms, multiple nodules in the lungs, and positive proteinase 3 (PR3)-ANCA (41 U/mL) and was treated with prednisolone and methotrexate; he did not receive heparin therapy.