ARUP's Laboratory Test Directory

Anti-Neutrophil Cytoplasmic Antibody with Reflex to Titer and MPO/PR-3 Antibodies : 2002068

Mnemonic: ANCA PN

Ordering Recommendation: Preferred panel for evaluating and managing individuals with a known diagnosis of vasculitis. Preferred reflex panel for the workup of suspected vasculitis is ANCA-Associated Vasculitis Profile (ANCA/MPO/PR-3) with Reflex to ANCA Titer (2006480).
Methodology: Semi-Quantitative Indirect Fluorescent Antibody/Semi-Quantitative Multiplex Bead Assay
Performed: Mon-Sat
Reported: 2-5 days
Specimen Required: Collect: 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: 0.5 mL)

Storage/Transport Temperature: Refrigerated.

Unacceptable Conditions: CSF, plasma, urine, or other body fluids. Contaminated, hemolyzed, or severely lipemic specimens.

Stability (collection to initiation of testing): After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Reference Interval:
 
Test Number Components Reference Interval
 Anti-Neutrophil Cytoplasmic Antibody, IgG < 1:20: Not significant
0050526Myeloperoxidase Antibody Negative: 19 AU/mL or less
Equivocal: 20-25 AU/mL
Positive: 26 AU/mL or greater
0050527Serine Protease 3 Antibody Negative: 19 AU/mL or less
Equivocal: 20-25 AU/mL
Positive: 26 AU/mL or greater

Interpretive Data: Neutrophil cytoplasmic antibodies (C-ANCA = granular cytoplasmic staining, P-ANCA = perinuclear staining) are found in the serum of over 90% of patients with certain necrotizing systemic vasculitides, and usually in less than 5% of patients with collagen vascular disease or arthritis. Approximately 90% of patients with a P-ANCA pattern by IFA have antibodies specific for myeloperoxidase (MPO).  Approximately 85% of patients with a C-ANCA pattern by IFA have antibodies specific for serine proteinase 3 (PR-3). 
Note: Specimens are screened by IFA on ethanol-fixed neutrophils, formalin-fixed neutrophils, and HEp-2 slides that allow differentiation of C- and P-ANCA patterns.

If screen is positive, then titer and MPO/PR-3 antibodies will be added to aid in antibody determination. Additional charges apply.
CPT Code(s): 86255; if reflexed, add 86256; 83516 x2
Cross References: ANCA Panel, IgG (Anti-Neutrophil Cytoplasmic Antibody with Reflex to Titer & MPO/PR-3 Antibodies), Anti-Neutrophil Cytoplasmic Antibodies Panel, IgG (Anti-Neutrophil Cytoplasmic Antibody with Reflex to Titer & MPO/PR-3 Antibodies) , c ANCA (Anti-Neutrophil Cytoplasmic Antibody with Reflex to Titer & MPO/PR-3 Antibodies), p ANCA (Anti-Neutrophil Cytoplasmic Antibody with Reflex to Titer & MPO/PR-3 Antibodies)