When used in conjunction with other autoantibody tests (ANCA, MPO), may assist in differentiating suspected Wegener granulomatosis (WG) from other vasculitides. May be useful when monitoring patients with PR-3 antibodies.
Panel tests are available. For the workup of suspected vasculitis, refer to ANCA-Associated Vasculitis Profile (ANCA/MPO/PR-3) with Reflex to ANCA Titer (2006480). For patients with a history of vasculitis, refer to Anti-Neutrophil Cytoplasmic Antibody with Reflex to Titer and MPO/PR-3 Antibodies (2002068).
- Patient Preparation
- Serum separator tube.
- Specimen Preparation
- 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)
- Storage/Transport Temperature
- Unacceptable Conditions
- 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)
Equivocal: 20-25 AU/mL
Positive: 26 AU/mL or greater
|Component Test Code*||Component Chart Name||LOINC|
|0050527||Serine Protease3, IgG||6968-2|
- PR3 Ab
- PR3 IgG Antibodies