What Is Congenital Rubella Syndrome?

1. If a pregnant woman develops rubella in early pregnancy, rubella virus can infect the fetus through the placenta, and the newborn baby can be immature, and can suffer from congenital heart malformations, cataracts, deafness, and developmental disorders. Congenital Rubella Syndrome (CRS)

Congenital rubella syndrome

1. If a pregnant woman develops rubella in early pregnancy, rubella virus can infect the fetus through the placenta, and the newborn baby can be immature, and can suffer from congenital heart malformations, cataracts, deafness, and developmental disorders, called congenital rubella or Congenital Rubella Syndrome (CRS)

2. Children have one or more birth defects after birth.

3. Specific rubella IgM antibodies were present in serum or cerebrospinal fluid specimens in early infancy.

4. When children passively obtain maternal antibodies 8 to 12 months after birth, there is still a considerable level of rubella antibodies in continuous serum samples.

Chinese name

Congenital rubella syndrome

Foreign name

congenital rubella syndrome (CRS)

Diagnosis

Pregnant

The principle of rubella virus causing special teratogenesis is not fully known. Pregnant women are infected with rubella and have had viremia one week before the rash. Whether the mother's rubella infection can be passed on to the fetus depends on how soon the mother becomes infected. The infection has the greatest effect on the heart and eyes at the second to sixth week of the embryo; in the second trimester, the fetus can gradually develop immunity (such as the appearance of plasma cells and the production of IgM), and the fetal-borne rubella infection is not as early as the first trimester That easily constitutes a chronic infection. According to Kibrick et al. (1974), the incidence of fetal congenital rubella syndrome can reach as high as 50% when pregnant women get rubella in the first month of pregnancy, 30% in the second month, 20% in the third month, and 4th month. 5%, and thought that rubella infection after 4 months of pregnancy is not completely safe for the fetus.

According to US literature reports, about 20% of women of childbearing age in cities are susceptible to rubella. At the time of the 1964 rubella pandemic, about 3.6% of pregnant women were infected with rubella, but the infection rate was only about 0.1% in non-epidemic years. 0.2%; the earlier the pregnant woman is infected with rubella, the more the fetus is infected, and the infection rate is very low in the second trimester, and the fetus may not be vulnerable to infection in the later period; during the pandemic, Siegal et al. Of these, 213 (64%) cases had induced abortion and 38 (11.4%) had spontaneous abortion. After the fetus is infected, 10 to 20% of the children die within one year after birth, and the rubella virus can be isolated from the dead tissue and body fluids. The virus can also be excreted from the throat and urine in the months after birth. This phenomenon of carrying the virus for a long time and continuously excreting the virus obviously poses a serious threat to the surrounding health-susceptible persons, especially pregnant women.

[Clinical manifestations]

After congenital infection with rubella, miscarriages, stillbirths, deformed live births or completely normal newborns can occur, and they can also be recessive infections. Almost all organs of the fetus can develop temporary, progressive, or permanent lesions.

1. Birth manifestations Infants with live births can exhibit some acute lesions, such as neonatal thrombocytopenic purpura, with scattered spots of varying purple-red size at birth, often accompanied by other temporary lesions and long bones Poor calcification of the palate, hepatosplenomegaly, hepatitis, hemolytic anemia, and full frontal canal, or there may be increased cerebrospinal fluid cells. These conditions are severe manifestations of congenital infections. Other manifestations at birth include low body weight, congenital heart disease, cataracts, deafness, and microcephaly. The prognosis is poor. According to the results of 58 cases of purpura infants following 1 year imitation, the mortality rate is as high as 35%. Rubella viral hepatitis and interstitial pneumonia can also occur in the neonatal period.

2. Malformations of the heart The most common cardiovascular malformations are arterial ducts. Some people even isolate rubella virus in the wall tissue of the duct. Pulmonary artery stenosis or stenosis of its branches are also more common. Other atrial septal defects, ventricular septal defects, aortic arch abnormalities, and more complicated deformities are also common. Most infants with mild cardiovascular symptoms at birth are not severe; however, those who have heart failure within the first month of life have a poor prognosis.

3. Deafness and hearing loss can be light or heavy, one or both sides. The lesions are present in the Corti cochlea of the inner ear. But there are also cases of middle ear lesions. Hearing loss can also be divided into the only manifestations of congenital rubella, especially seen in infected people after 8 weeks of pregnancy.

4. Eye defects The most characteristic eye lesions are piriform cataracts, most of which are bilateral or unilateral, often accompanied by small eyeballs. Cataracts may be small or invisible at birth and must be carefully examined with ophthalmoscope. In addition to cataracts, congenital rubella can also cause glaucoma, which is difficult to distinguish from hereditary infantile glaucoma. Glaucoma with congenital rubella appears as enlarged cornea and opacities, anterior chamber deepening, and increased intraocular pressure. Normal newborns can also have transient corneal opacities, which can disappear spontaneously and have nothing to do with rubella. Glaucoma with congenital rubella requires surgery; transient corneal opacities do not require treatment. The most common scattered melanin plaques on the retina vary in size. Most of these pigments are not harmful to vision, but their presence is helpful for the diagnosis of congenital rubella.

5. Developmental disorders and neurological malformations Infant rubella can also cause disease in the central nervous system. Autopsy of the infant confirmed that rubella virus is very toxic to nerve tissue, causing developmental defects of varying degrees. There are often changes in the cerebrospinal fluid, such as increased cell numbers and increased protein concentrations, and the virus can still be isolated from the cerebrospinal fluid even at the age of 1 year.

Developmental disorders in intelligence, behavior and movement are also a major feature of congenital rubella. This early developmental disorder is caused by rubella encephalitis and may cause permanent mental retardation.

Generally speaking, congenital heart malformations, cataracts and glaucoma are often due to viral infection in the first 2 to 3 months of pregnancy, while hearing loss and central nervous system lesions are often infected later in pregnancy. Newborns can also use transient congenital rubella, which is often transmitted by infections in early pregnancy, but occasionally due to infection in late pregnancy, the mother and the fetus are at the same time.

For the prevention of congenital rubella syndrome, see Prevention of rubella above. It is worth noting that rubella reinfection can also affect the fetus during pregnancy. Pregnant women who have been vaccinated against rubella have a much greater chance of reinfection than pregnant women who have had rubella naturally. During pregnancy, the adrenal cortex hormones increase, and the cellular immune function decreases. Therefore, the virus easily spreads in the body, which affects the fetus.

For non-pregnant people, rubella reinfection is almost asymptomatic, and there is no viremia, just like the booster of the vaccine, it causes increased antibodies in the body. However, congenital rubella syndrome may occur after reinfection in pregnant women. Therefore, even if pregnant women have been vaccinated against rubella, they should also pay attention to strict isolation from rubella patients.