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Toxoplasma Antibody, IgM

Mnemonic:    [Toxopl IgM]
Name:    Toxoplasma Antibody, IgM
Specimen:    1 mL serum from a Red SST or Red top tube. Allow specimen to clot completely at room temperature. Separate serum from cells ASAP or within 2 hours of collection.

Parallel testing is preferred and convalescent specimens must be received within 30 days from receipt of the acute specimens. Mark specimen plainly as "acute" or "convalescent."
Minimum Spec:    0.5 mL
Transport Temp:    Refrigerated
Spec Stability:    Stable up to 2 weeks refrigerated.
Ref Lab/Code:    ARUP 0050557
  Method:    Chemiluminescent Immunoassay
Note:    Interpretive Data: This test is performed using the Siemens Immulite 2000 chemiluminescent immunoassay. As suggested by the CDC, any equivocal or positive 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 assay from another reference laboratory specializing in toxoplasmosis testing, such as Palo Alto Medical Foundation (Remington),where the IgM ELISA should be ordered or, as indicated, the Toxoplasma Serologic Profile. Caution should be exercised in the use of IgM antibody levels in prenatal screening. Any positive results in pregnant patients, that are confirmed positive by a second reference laboratory, should be evaluated by amniocentesis and PCR testing for Toxoplasma gondii.

For male and non-pregnant female patients with equivocal or positive Toxoplasma gondii IgM results, PCR may also be useful if a specimen can be collected from an affected body site.