Treponema pallidum, IgG antibodies

Why this test?

For the diagnosis of syphilis.

For the examination of all pregnant women for preventive purposes (preferably at the first gynecologist appointment, when registering).

In what cases is it prescribed?

For symptoms of syphilis, such as a hard chancre on the genitals or in the throat.

When a patient is being treated for another STD, such as gonorrhea.

During pregnancy, because syphilis can be transmitted to the developing fetus and even kill it.

When it is necessary to determine the exact cause of the disease, if the patient has non-specific symptoms that are similar to syphilis (neurosyphilis).

If the patient is infected, he should repeat the syphilis test after 3, 6, 12 and 24 months to make sure that the treatment has been successful.

Test information

Syphilis is an infectious disease that is most often transmitted sexually, such as through direct contact with a syphilitic ulcer (hard chancre). It is easily curable, but if left untreated, it threatens serious health problems. An infected mother can transmit the disease to her fetus, which later develops serious abnormalities.

There are several stages of syphilis. The primary occurs approximately 2-3 weeks after infection. One or sometimes several ulcers, called chancres, appear, as a rule, on the part of the body that was in contact with the chancre of the sick person, for example, the penis or vagina. Most often, a hard chancre is painless and remains unnoticed, especially if it is located in the rectum or on the cervix. The chancre disappears after 4-6 weeks.

Secondary syphilis begins 2-8 weeks after the appearance of a hard chancre. This stage of the disease is characterized by the appearance of a rash on the skin, more often on the palms and soles. Sometimes there are other symptoms, such as fever, fatigue, swollen lymph nodes, sore throat, and body aches.

Syphilis can occur in a latent form, during which the infected person does not show any symptoms, but at the same time he continues to be a carrier of the infection. This can happen for years.

Without treatment, about 15% of patients develop symptoms of late, or tertiary, syphilis. This stage sometimes lasts for several years and leads to mental illness, blindness, neurological problems, heart disease and even death.

You can get rid of syphilis with the help of antibiotics (preferably penicillin derivatives). Moreover, in the early stage of the disease, it is easier and faster to treat. Note that patients infected for more than a year may require longer treatment.

When there is human contact with t. pallidum, his immune system responds by producing antibodies against the bacteria. Two types of such antibodies can be detected in the blood: IgM and IgG.

Immunoglobulins of class G to t. pallidum in determined quantities appear in the blood after 3-4 weeks from the moment of infection. Their concentration increases and in the 6th week begins to prevail over the concentration of IgM, reaching a maximum, and then remains at a certain level for a long time. After effective treatment, the level of immunoglobulins gradually decreases, but this happens much more slowly than in the case of IgM. As a rule, IgG in specified quantities can be detected a year or more after the therapy, and in some cases even after a decade.

There are several methods that can be used to test for syphilis, the most sensitive and specific for detecting treponemal antibodies at all stages.