Myeloperoxidase Antibodies, IgG, Serum

Casandra

Casandra Test Code MC81202Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID MPOCPT Code 83516

Myeloperoxidase Antibodies, IgG, Serum

Clinical Use

Use

Evaluates patients with clinical features of anti-neutrophil cytoplasmic antibody-associated vasculitis, such as granulomatosis with polyangiitis and microscopic polyangiitis (MPA). It helps distinguish between MPA and other forms of ANCA-associated vasculitis when used in conjunction with proteinase 3 antibody and cytoplasmic neutrophil antibody testing. The test is also useful for following treatment response or monitoring disease activity in patients with myeloperoxidase (MPO) antibodies.

Special Instructions

For more accurate diagnosis or monitoring, it might be necessary to order additional tests such as PR3 / Proteinase 3 Antibodies, IgG, Serum and ANCA / Cytoplasmic Neutrophil Antibodies, Serum. Alternatively, ordering a comprehensive panel like the VASC / Antineutrophil Cytoplasmic Antibodies Vasculitis Panel, Serum could provide broader initial screening.

Limitations

Positive results for MPO-ANCA or PR3-ANCA through either immunofluorescence or antigen-specific immunoassay must be interpreted with caution and within the clinical context. Negative results do not entirely exclude the diagnosis of ANCA-associated vasculitis due to potential variability in antibody levels or presence that fall below detection thresholds. Continuous monitoring of antibody levels should not solely be relied upon for treatment response evaluation or the prediction of disease activity and flare risk. Interpretation of results should also consider potential interfering factors such as specimen mis-handling or other technical variables.

Test Details

FDA Approved