They typically have fewer extrarenal symptoms than patients with ANCA positive GN.
Patients with ANCA negative disease have been described to have higher proteinuria than their counterparts.
Pathogenesis is unclear but neutrophils leading to respiratory burst and free radical injury are quintessential; how they are stimulated is a matter of debate. Anti endothelial cell antibodies (AECA) and Anti lysosomal protein antibody are some of the other antibodies that can stimulate neutrophils but they are also present in ANCA pos patients. Role of cell mediated immunity is also being studied.
Treatment modalities are similar and outcomes are comparable. Some of the major studies looking at ANCA negative PICGN are summarised below -