Although the authors found that rises in ANCA titers during follow-up of AAV patients is not a very sensitive or specific predictor of relapse in general, they observed that the rise of PR3-ANCA level during complete remission conveys an increased risk of relapse among patients with renal vasculitis (HR 7.94) or alveolar hemorrhage (HR 24.19) and those treated with rituximab (but not those treated with cyclophosphamide and azathioprine). Here, PRTN3 is linked to anti-neutrophil cytoplasmic antibody-associated vasculitis.