Order Code LAB898 Myeloperoxidase Antibodies, IgG, Serum
Additional Codes
Mayo Test ID |
---|
MPO |
Reporting Name
Myeloperoxidase Ab, SUseful For
Evaluating patients with clinical features anti-neutrophil cytoplasmic antibody associated vasculitis, specifically granulomatosis with polyangiitis, microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis
Distinguishing between MPA and other forms of ANCA-associated vasculitis, in conjunction with proteinase 3 antibody and cytoplasmic neutrophil antibody testing
Following treatment response or monitoring disease activity in patients with myeloperoxidase (MPO) antibodies
Specimen Type
SerumAdditional Testing Requirements
To distinguish between microscopic polyangiitis and other forms of anti-neutrophil cytoplasmic antibody-associated vasculitis, also order PR3 / Proteinase 3 Antibodies, IgG, Serum and ANCA / Cytoplasmic Neutrophil Antibodies, Serum; alternatively, VASC / Antineutrophil Cytoplasmic Antibodies Vasculitis Panel, Serum may be ordered instead, which initially tests for myeloperoxidase and proteinase 3 antibodies, with reflex to ANCA when appropriate.
Specimen Required
Supplies: Sarstedt Aliquot Tube 5 mL (T914)
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Specimen Minimum Volume
0.35 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 21 days | |
Frozen | 21 days |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | OK |
Reference Values
<0.4 U (negative)
0.4-0.9 U (equivocal)
≥1.0 U (positive)
Reference values apply to all ages.
Performing Laboratory
Mayo Clinic Laboratories in RochesterDay(s) Performed
Monday through Saturday
Method Name
Multiplex Flow Immunoassay
CPT Code Information
83516
Method Description
Myeloperoxidase (MPO) antigen is covalently coupled to polystyrene microspheres that are impregnated with fluorescent dyes to create a unique fluorescent signature. MPO antibodies, if present in diluted serum, bind to the MPO antigen on the microspheres. The microspheres are washed to remove extraneous serum proteins. Phycoerythrin (PE)-conjugated antihuman IgG antibody is then added to detect anti-MPO IgG bound to the microspheres. The microspheres are washed to remove unbound conjugate, and bound conjugate is detected by laser photometry. A primary laser reveals the fluorescent signature of each microsphere to distinguish it from microspheres that are labeled with other antigens. A secondary laser reveals the level of PE fluorescence associated with each microsphere. Results are calculated by comparing the median fluorescence response for MPO microspheres to a 4-point calibration curve.(Package insert: Bio-Plex 2200 Vasculitis. Bio-Rad Laboratories; 02/2018)
Forms
If not ordering electronically, complete, print, and send a Renal Diagnostics Test Request (T830) with the specimen.