Toxoplasmosis is an infectious disease caused by Toxoplasma gondii, which belongs to the protozoa (primordial animals).Toxoplasmosis is common worldwide. In Germany, infestation among the elderly is up to 70%.Once a patient is infected, he or she remains infected for life, i.e. reactivation (i.e. a new outbreak of the disease) is possible at any time.The incubation period (period between the penetration of the pathogen into the body and the appearance of the first symptoms, i.e. the outbreak of the disease) is two to three weeks.
Cause
Toxoplasmosis infection is caused by the pathogen Toxoplasma gondii, which can be transmitted by egg-shedding cats and during consumption of infected raw meat and unwashed, uncooked vegetables.
The primary host of the pathogen is the cat; humans are only a secondary host.
Infection usually occurs via ingestion of contaminated food or soil, for example during gardening, or diaplacentally, that is, from the mother via the placenta (placenta) to the unborn child. In addition, there is a small risk of becoming infected with the pathogen during blood transfusions and organ transplants.
If the initial infection of the mother takes place during pregnancy and the child is also infected, the following complications may occur for the child:
- Chorioretinitis (inflammation of the choroid (choroid) and retina (retina) of the eye).
- Hydrocephalus (hydrocephalus)
- Hepatomegaly (enlargement of the liver)
- In the worst case, the child may die before birth.
If the mother already has the infection before pregnancy (serological evidence / blood test), there is no longer a risk for the child.
Laboratory diagnostics
Toxoplasmosis testing is required in the following cases:
- Before a planned pregnancy, the following women should be tested:
- With infertility and desire to have children
- With a stressed pregnancy or birth history
- Without known immune status
- During pregnancy, the following women should be screened:
- Without known immune status
- After infertility treatment or with a strained pregnancy or birth history.
- Without immunity after infertility treatment or with strained pregnancy or birth anamnesis.
- Regardless, screening should be sought in pregnant women with unknown immune status or lack of immunity.
Laboratory parameters 1st order – mandatory laboratory tests.
- Direct microscopic detection of the pathogen in the blood.
- Toxoplasma gondii antibody detection (IgM/IgG detection in immunofluorescence).
Pregnant women should be retested serologically (from blood) 14 days after a positive IgM test.In pregnant women without immunity, repeated tests should be performed preferably at intervals of eight weeks, but at least not greater than twelve weeks until the end of pregnancy. 2nd order laboratory parameters – depending on the results of the medical history, physical examination, etc. – for differential diagnostic clarification.
- Toxoplasma gondii DNA detection (genetic detection of Toxoplasma gondii infection).
Interpretation
| Toxoplasma gondii IgG | Toxoplasma gondii-IgM | Results, usually indicate the following infection status. |
| Low | Low | Not relevant, inactive infection |
| High | Low | Decaying infection |
| High | High | Recent infection |
| Low | High | Acute infection |
