Toxoplasmosis IgG Antibody
Label Mnemonic: TOXOG
Epic Lab Code: LAB2423
Downtime Form: A-1a General Laboratory Requisition
Chemistry
6240 RCP
356-3527
Specimen(s):
Serum
Collection Medium:
Red top tube 5 mL (Clot Activator)
Alternate Collection Media:
Call laboratory for additional acceptable specimen collection containers.
Minimum:
3.0 mL whole blood from red top tube or TWO Microtainer® devices.
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
3 hours (upon receipt in laboratory)
Reference Range:
Reference range and methodology changed effective 12/11/2012.

9 IU/mL or less: Negative - No significant level of detectable Toxoplasma gondii IgG antibody.

10-11 IU/mL: Equivocal - Repeat testing in 10-14 days may be helpful.

12 IU/mL or greater: Positive - IgG antibody to Toxoplasma detected, which may indicate a current or past Toxoplasma infection.
Interpretive Data:
The best evidence for current infection is a significant change on two appropriately timed specimens, where both tests are done in the same laboratory at the same time.
Comments:
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."

Toxoplasmosis is an infection caused by the parasite Toxoplasma gondii. The infection is mainly acquired by ingestion of food or water that is contaminated by mature oocysts shed by cats or by undercooked meat containing tissue cysts. Primary acute infection occurs in many individuals and usually produces mild symptoms followed by a latent period that may persist for life. However, reactivation of a latent Toxoplasma infection as a result of immunosuppression can lead to meningoencephalitis.

Primary maternal Toxoplasma infection occurring during pregnancy can lead to severe damage of the fetus as the parasite can be transmitted across the placenta. Infants with congenital infection often do not present with clinical symptoms at birth but may develop severe sequelae later in life such as mental and psychomotor retardation, chorioretinitis and hearing loss. The fetal infection rate increases with gestational age at which the mother acquires Toxoplasma infection. However, the risk of severe clinical manifestations is higher in case of early maternal infection. Early drug therapy in acute infection during pregnancy can prevent congenital damage or ameliorate the severity of clinical manifestations. The diagnosis of Toxoplasma infection is most commonly made by the detection of IgG and IgM antibodies directed against Toxoplasma. The determination of IgG antibodies to Toxoplasma gondii is used to assess the serological status to T. gondii and is indicative of an acute or latent infection. The detection of IgM antibodies to T. gondii indicates an acute, recent or reactivated Toxoplasma infection. The diagnosis of the acute acquired infection during pregnancy is established by a seroconversion or a significant rise in antibody titers (IgG and/or IgM) in serial samples.
Test Limitations:
The performance characteristics have not been established for cord blood testing and neonates.
Methodology:
Multiplex Flow Immunoassay
CPT Code:
86777
 
See also:
Toxoplasmosis Antibody, IgM, Serum