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 -
1. Some people might say there are 5 types of RPGN:
I:- Anti GBM
II:- Immune complex
III:- ANCA+ pauci immune
IV:- Anti GBM + anca + disease
V:- Anca negative Pauci immune
2. The antibodies you are referring to in ANCA negative disease might be LAMP-2 perhaps. There is some thought in possibly a molecular mimicry with a bacterial antigen.
3. Treatment of pauci immune GN is similar to ANCA+ disease in terms of steroids/cytoxan or Rituximab. Although I don't know what the data is on Pheresis in ANCA negative Pauci Immune RPGN if they present with Crt>5.5 mg/dl or on hemodialysis and or with hemoptysis.
Thank you for clarifying.ReplyDelete