The toxoplasma blood test looks for antibodies in the blood to a parasite called Toxoplasma gondii.
How the Test is Performed
A blood sample is needed.
How to Prepare for the Test
There is no special preparation for the test.
How the Test will Feel
When the needle is inserted to draw blood, some people may feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.
Why the Test is Performed
The test is done when the health care provider suspects that you have toxoplasmosis. The infection is a danger to a developing baby if a pregnant woman gets infected. It is also dangerous in people with HIV/AIDS.
In pregnant women, the test is done to:
- Check if a woman has a current infection or had an infection in the past.
- Check if the baby has the infection.
The presence of antibodies before pregnancy probably protects a developing baby against toxoplasmosis at birth. But antibodies that develop during pregnancy may mean the mother and baby are infected. This infection during pregnancy increases the risk for miscarriage or birth defects.
This test may also be done if you have:
- An unexplained lymph node swelling
- An unexplained rise in the blood white cell (lymphocyte) count
- HIV and have symptoms of a toxoplasmosis of the brain (including headache, seizures, weakness, and speech or vision problems)
- Inflammation of the back part of the eye (chorioretinitis)
Normal Results
Normal results mean you have likely never had a toxoplasma infection.
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test result.
What Abnormal Results Mean
Abnormal results mean that you have probably been infected with the parasite. Two types of antibodies are measured, IgM and IgG:
- If level of IgM antibodies is raised, you likely became infected in the recent past (or current).
- If level of IgG antibodies is raised, you became infected sometime in the past.