Name |
Myeloperoxidase Antibodies (IgG) |
Alternative name/Profile |
PR3 antibodies, ANCA, Cytoplasmic Neutrophil Antibodies, Perinuclear Cytoplasmic Antibodies, pANCA, cANCA, Myeloperoxidase, MPO, Proteinase 3, PR3, Wegener's Granulomatosis, Granulomatosis with Polyangitis, GPA, Microscopic Polyangitis, MPA, GBM, Glomerular Basement Membrane Antibodies, Glomerulonephritis, Goodpasture Syndrome, Goodpasture's Syndrome |
Department |
Immunology |
Investigation |
Immunoassay (Phadia 2500 and ImmunoCap 250) |
Specimen type |
Clotted blood
|
Sample type |
Serum |
Sample container & volume |
5ml Red |
Frequency of analysis |
Daily, Monday to Friday. |
Turnaround time |
3 days
|
Availability |
|
Notes |
Useful for:
- Investigating patients suspected of having immune-mediated vascultitis, particularily Microscopic Polyangitis.
- Distinguishing between forms of Autoimmune Vaculitis.
- Monitoring a patient's disease activity or response to treatment (in conjunction with Anti-Neutrophil Cytoplasmic Antibodies (ANCA) titre).
Clinical Information:
- Anti-Neutrophil Cytoplasmic Antibodies (ANCA) occur in patients with Autoimmune Vasculitis.
- Anti-Neutrophil Cytoplasmic Antibodies (ANCA) are directed against enzymes in the cytoplasmic granules of human neutrophils such as Proteinase 3 (PR3), Myeloperoxidase (MPO), Elastase, or Cathepsin G.
- MPO catalyses the conversion of hydrogen peroxide to hypochlorite and hypochlorous acid.
- Anti-Neutrophil Cytoplasmic Antibodies (ANCA) directed against Myeloperoxidase (MPO) can be found in patients with Microscopic Polyangitis, Systemic Lupus Erythematosus (SLE) with or without lupus nephritis, Goodpasture's Syndrome and Churg-Strauss Syndrome.
Please Note:
- All patients with an Anti-Neutrophil Cytoplasmic Antibody (ANCA) request are screened at a dilution of 1:20. Only positive samples have a Myeloperoxidase (MPO) and Proteinase 3 (PR3) immunoassay performed. This is requested by the laboratory.
- All requests for Myeloperoxidase (MPO) will also have a Proteinase 3 (PR3) immunoassay performed. This is requested by the laboratory.
- New patients with a positive Proteinase 3 (PR3) and/or Myloperoxidase (MPO) antibody will have a Glomerular Basement Membrane (GBM) Antibody immunoassay performed. This is requested by the laboratory.
- This test is also available on an urgent basis by arrangement with the laboratory. For urgent tests the turnaround time is approximately three hours from specimen receipt. The cut-off time for sample receipt is 15.00 on Fridays.
- Where External Institiutions cannot guarantee immediate delivery, samples must be centrifuged, separated and stored at 4oC. Samples can then be transported, as soon as possible, to St. James's Hospital for processing.
|
Related links |
Clarification of arrangements for Urgent ANCA & anti-GBM |
Reference range |
<3.5 IU/ml = Negative
3.5-5.0 IU/ml = Equivocal
>5.0 IU/ml = Positive
Reference Ranges provided by Phadia 2006. |
Last updated |
Fri, 19 Jul 2024 09:36:56 IST |
