Toxoplasmosis Antibody, IgM
Label Mnemonic: TOXOM
Epic Lab Code: LAB2424
Downtime Form: A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery
Commercial Mail-out Laboratory
5231 RCP
Collection Medium:
Red top tube 5 mL (Clot Activator)
Preferred Minimum: 1 mL serum
Absolute Minimum: 0.5 mL serum
Rejection Criteria:
Grossly hemolyzed, contaminated or heat-inactivated specimens.
Turn Around Time:
24 hours upon receipt at reference laboratory
Reference Range:
7.9 AU/mL or less: Not Detected 8.0 - 9.9 AU/mL: Indeterminate - Repeat testing in 10-14 days may be helpful. 10.0 AU/mL or greater: Detected - Significant level of Toxoplasma gondii IgM antibody detected and may indicate a current or recent infection. However, low levels of IgM antibodies may occasionally persist for more than 12 months post- infection.
Interpretive Data:
This test is performed using the DiaSorin LIAISON. As suggested by the CDC, any indeterminate or detected Toxoplasma gondii IgM result should be retested in parallel with a specimen collected 1-3 weeks later. Further confirmation may be necessary using a different test from another reference laboratory specializing in toxoplasmosis testing, where an IgM ELISA should be ordered. Caution should be exercised in the use of IgM antibody levels in prenatal screening. Any Toxoplasma gondii IgM in pregnant patients that have also been confirmed by a second reference laboratory should be evaluated by amniocentesis and PCR testing for Toxoplasma gondii.

For male and non-pregnant female patients with indeterminate or detected Toxoplasma gondii IgM results, PCR may also be useful if a specimen can be collected from an affected body site.
Acute and convalescent specimens must be labeled as such; parallel testing is preferred and convalescent specimens must be received within 30 days from receipt of the acute specimens. Please mark specimen plainly as "acute" or "convalescent."
Semi-Quantitative Chemiluminescent Immunoassay
CPT Code:
See also:
Toxoplasmosis IgG Antibody, Serum