When used in conjunction with other autoantibody tests (ANCA, MPO), may aid in differentiating suspected Wegener granulomatosis (WG) from other vasculitides. May be useful to monitor patients with PR3 antibodies.
Panel tests are available. For the workup of suspected vasculitis, refer to ANCA-Associated Vasculitis Profile (ANCA/MPO/PR3) (3003745). For patients with a history of vasculitis, refer to Myeloperoxidase (MPO) Antibody and Serine Proteinase 3 (PR3) Antibody with Reflex to Anti-Neutrophil Cytoplasmic Antibody, IgG by IFA (3003746).
Semi-Quantitative Multiplex Bead Assay
New York DOH Approval Status
Serum separator tube.
Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.2 mL)
Plasma, urine, or other body fluids. Contaminated, hemolyzed, or severely lipemic specimens.
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
|Negative||19 AU/mL or less|
|Positive||26 AU/mL or greater|
Approximately 85% of patients with a C-ANCA pattern by IFA have antibodies specific for PR3.
|Component Test Code*||Component Chart Name||LOINC|
|0050527||Serine Proteinase 3 (PR3) Ab, IgG||6968-2|
- PR3 Ab
- PR3 IgG Antibodies