Toxoplasma gondii, IgM antibodies
Why this test?
To determine whether a woman planning pregnancy has been infected and whether she has immunity to this infection.
During pregnancy, the study is necessary if a possible infection is suspected.
To detect infection in immunocompromised people who are suspected of having toxoplasmosis or who have severe symptoms.
In what cases is it prescribed?
The determination of T. gondii antibodies is not usually a routine test for pregnant women, but may be necessary if the patient has been in contact with cat feces, raw (or undercooked) meat, or contaminated food (water), or if the doctor wants to determine whether the women previously had toxoplasmosis. If the antibody test is negative, but toxoplasmosis is still suspected, the test can be repeated one or more times during pregnancy.
This test is sometimes prescribed to people with weakened immune systems who have flu-like symptoms, as well as those who have symptoms or complications typical of toxoplasmosis.
This analysis is performed for the purpose of diagnosing current or past infection with Toxoplasma gondii. T. gondii is a microscopic parasite whose primary host is the cat. It can be found in the soil. In most healthy people, this infection does not cause any symptoms or occurs in the form of mild flu-like illnesses. When an infected pregnant woman transmits the infection to her child or a person with a weakened immune system becomes infected, the microorganism can cause serious complications.
T. Gondi is very common. It is found all over the world, and in some countries up to 95% of the population is infected.
According to the Ministry of Health, about 23% of people over the age of 12 suffer from toxoplasmosis. Infection occurs through consumption of contaminated food or water, especially if raw or undercooked meat is eaten, as well as when picking up cat litter, when the virus is transmitted from mother to child, and in rare cases during organ transplants or blood transfusions.
The final hosts for T. Gondi are wild and domestic cats. After they become infected by eating infected birds, rodents and raw meat waste, T. gondii undergo a sexual development cycle that leads to the formation of eggs enclosed in a protective shell (oocyst).
During an active infection with cat feces, millions of microscopic oocysts can be released in a few weeks. They become contagious within a couple of days and can remain viable for several months. In all other hosts, including humans, T. gondii pass only a limited part of their life cycle and then form inactive cysts in the muscles, brain, and eyes. The host's immune system keeps these cysts at bay and protects the human body from further infection.
The latent period can last throughout the life of the host until immunity declines. Primary or repeated infection with T. gondii leads to severe symptoms and complications in people with weakened immune systems, such as HIV/AIDS patients undergoing chemotherapy, organ transplant patients, or immunosuppressants.
The eyes and nervous system can be affected, causing headaches, convulsions, confusion, fever, encephalitis, loss of coordination and blurred vision. If a woman is infected during pregnancy, the probability that the infection will be transmitted to the future child is 30-40%.
Moreover, if the infection occurs at the beginning of pregnancy, it can cause miscarriages, stillbirths or lead to serious complications in newborns, including mental retardation, convulsions, blindness and enlargement of the liver or spleen.
Many infected children, especially those infected late in pregnancy, are born healthy, but several years later develop severe eye infections, hearing loss, and mental retardation.
When a person comes into contact with T. gondii, his immune system reacts by producing antibodies against the parasite. Two types of antibodies to toxoplasma can be detected in the blood: IgM and IgG. IgM antibodies are produced first. They are determined in most people 1-2 weeks after the first contact. The production of IgM antibodies increases for a short period and then decreases. Ultimately, several months after the initial infection, the IgM antibody titer falls below the level detected in most people. Additionally, IgM can be produced when latent T. Gondi are activated and/or when a person has a chronic infection. IgM is the only type of antibody produced by the fetus. If they are determined in newborns, then this indicates a congenital infection.