Toxoplasma IgG (Toxoplasma Antibody)

What is Toxoplasma IgG?

Toxoplasmosis is a very common infection worldwide, caused by a single-celled parasite called Toxoplasma gondii. It is mostly transmitted to humans through undercooked meat, poorly washed vegetables and fruit, or soil contaminated with cat feces. In healthy people it usually causes no symptoms or passes as a mild flu-like illness; however, if it is contracted for the first time during pregnancy, the parasite can pass to the baby.

Toxoplasma IgG are antibodies that the body produces against this parasite and that usually remain in the blood for life after the infection. Their presence in the blood shows that the person has been exposed to the parasite in the past. After the infection has passed, the parasite can remain in the body in an inactive form, and a healthy immune system keeps it under control. The test is run on blood serum using the ELISA method and gives the result as positive or negative.

When is the Toxoplasma IgG test ordered?

The test is mostly ordered for women who are planning a pregnancy or are in early pregnancy, to determine whether they have had the infection before and therefore how careful they need to be about protection during pregnancy. As part of TORCH screening, it is usually assessed together with Toxoplasma IgM. In people with suppressed immunity, it is important for knowing the risk of possible reactivation in advance. It can also be used to investigate toxoplasma as one of the possible causes in conditions such as eye inflammation or unexplained lymph node enlargement.

• Preparation before pregnancy and pregnancy screening
• Assessment before an organ transplant or immunosuppressive treatment
• Baseline assessment in diseases that weaken the immune system
• Prolonged swollen lymph nodes and fatigue
• Suspected eye inflammation causing blurred vision (retinochoroiditis)

How should I prepare for the Toxoplasma IgG test?

No fasting or special preparation is required for this test. If you are pregnant, sharing with your doctor how many weeks pregnant you are and the results of any previous toxoplasma tests helps changes in antibody levels to be interpreted correctly. If you have recently received blood products, you should also mention this, as antibodies passed on from the donated blood can affect the result. You do not need to stop any of your medications for the test; if your doctor has given you specific advice, follow it.

Blood is taken from an arm vein with single-use equipment, and the serum portion is tested. If you would like to avoid extra trips during pregnancy, a Curavita nurse can come to your home or workplace for the blood draw. You can return to your daily activities immediately after the procedure.

What does the Toxoplasma IgG result mean?

A positive result shows that you have been exposed to the parasite before. If IgM is negative, the infection is considered to have occurred in the past; in people with a healthy immune system, an infection acquired before pregnancy generally poses no risk of transmission to the baby. If IgM is also positive, additional tests such as an avidity measurement are used to clarify the timing of the infection. In a person who was previously negative, IgG turning positive suggests a new infection and should be assessed with a doctor without delay.

A negative result shows that you have not been exposed to the parasite before and may be unprotected against infection during pregnancy. In this case, precautions are recommended such as cooking meat thoroughly, washing vegetables and fruit well, and wearing gloves when in contact with soil and cat litter; your doctor may ask for the test to be repeated during pregnancy. On the other hand, in people with suppressed immunity, a positive IgG may require monitoring because of the possibility of the parasite reactivating. Reference values may vary by laboratory and, for some tests, by age and sex; the laboratory's own reference is shown on this page. Your doctor should interpret your results by considering them together with any complaints and other test findings.