Culture of the material for GBS

Sampling is not performed at the Point of Collection. In order to perform the test, you must provide a sample taken at the doctor's office.

Sample collection for GBS testing

Streptococcus agalactiae (group B streptococcus, GBS) under physiological conditions is a harmless bacterium that is part of the normal flora of the female genital tract, upper respiratory tract and lower gastrointestinal tract. It is estimated that colonization (colonization by the pathogen) of the vagina occurs from the rectum, it occurs in up to 30% of women regardless of whether they are pregnant or not. The state of asymptomatic carriage, once the bacteria is detected from a vaginal swab, does not require treatment.

During pregnancy, the bacterium can adversely affect the course of pregnancy or threaten the health of the baby immediately after delivery. There are many changes in the genital organs of the pregnant woman, which increase the risk of uncontrolled growth of the microorganism and cause urogenital infections - in mild cases these are vaginal infections, in severe cases there may be inflammation of the membranes, placenta, uterus, which may end in premature birth. In such cases, there is a need to identify the source of the infection and implement antibiotic therapy to prevent complications.

Also, if a woman's genital tract is colonized with S. agalactiae, transmission of the pathogen to the newborn can occur during the delivery itself. This situation is facilitated by premature rupture of the fetal membranes before delivery, fever in the mother during labor and premature delivery (before 37 weeks). Since the baby's immune system is not yet fully formed and does not function as it should, the course of infection is much more severe in newborns.

Group B streptococci cause two types of infections in children:

• early (symptoms appear up to 7 days after birth, may involve meningitis or pneumonia)
• late (symptoms appear from 7 days to 3 months after birth, mainly result from infections of the central nervous system or bones and joints)

Additionally, serious GBS infections are increasingly seen in the elderly and immunocompromised. They may be limited to the genitourinary system, but if the bacteria enter the blood, they can affect any organ (skin, soft tissues, endocardium, marrow, meninges) and pose a life-threatening risk.

When to perform material culture for GBS?

This test is routinely performed in women at 35-37 weeks' gestation to detect group B vaginal and rectal streptococci.

The test is also routinely performed in women at 35-37 weeks' gestation to detect group B vaginal and rectal streptococci

When a urogenital infection is suspected in a pregnant woman due to a bacterial infection, urine may also be cultured. Particularly heightened vigilance is required if there is a history of infection of the baby in previous pregnancies.

Particularly heightened vigilance is required if there is a history of infection of the baby in previous pregnancies

In situations where the baby has symptoms of sepsis and an infection is suspected, it is necessary to culture his blood for S. agalactiae. This test is also used when disseminated infection is suspected in adults.

Who should perform a culture of material for GBS?

Pregnant women with symptoms of genitourinary tract infections:

• discomfort during urination
• frequent urination
• feeling of urinary urgency
• unusual vaginal discharge
• pruritus, vaginal burning
• pain in lower abdomen

Particularly if in previous pregnancies, the newborn after delivery had symptoms:

• sepsis (fever, decreased blood pressure, decreased appetite, increased heart rate, vomiting)
• pneumonia (difficulty breathing)
• meningitis (neck stiffness, apathy, irritability, convulsions)