Apr 30, 2018
Infection of the fetus during development in the body of a pregnant woman can lead to various infectious diseases, united by a common name - a fetal infection. . A child can become infected with
by the personal pathogens of infectious diseases during childbirth( when passing through infected birth canal) or after birth( through maternalmilk and other biological fluids).Infectious diseases that developed as a result of these causes were called neonatal infections( intra- and postnatal).Many infants who become infected during or after childbirth may have an asymptomatic infection. However, some of them, especially preterm, develop marked clinical manifestations of the disease with severe course. Perinatal infections are infectious diseases caused by fetal infection during fetal development, at birth or after birth.
In recent years, there has been a significant increase in the incidence of congenital infections, with a predominantly viral etiology. Viral infections cause up to 80% of congenital malformations in children, among them the leading place is occupied by lesions of the central nervous system, as well as congenital heart and kidney defects. Numerous scientific data testify to the etiological relationship of congenital malformations in children with viral infections transplanted during pregnancy or with transplacental transmission of viruses from a pregnant woman with a persistent form of infection.
The most common perinatal infections include herpes, CMV, parvovirus and toxoplasma infections, rubella, chlamydia. Timely diagnosis and treatment of these infections in women is an urgent problem of modern clinical practice.
Virologic examination of newborns and pregnant women allows to diagnose viral infection in the vast majority of the examined( up to 98%).
Early and timely diagnosis of viral infection in pregnant and congenital infections in children allows us to develop optimal therapeutic tactics of management, rational use of drugs with an antiviral focus in order to reduce the likelihood of developmental malformations in children.
If a suspected intrauterine infection is suspected, pregnant women are most often screened for herpes, tsmv, parvovirus, chlamydia and toxoplasma infections, and rubella. Negative results of studies in most cases allow to exclude the possibility of infection of the fetus. If there is a suspicion of intra- and postnatal infection, it is necessary to conduct a parallel examination of the blood of the mother and child. In this case, different situations are possible, causing difficulties for physicians in interpreting the results. The most common ones are listed in the table.
When using the data given in Table 1, it is necessary to take into account that the detection of only Ig Ig in a newborn is poorly informative because of the transplantent penetration of the parent AT in its organism during intrauterine development. Therefore, to exclude infection, it is necessary to determine the Ig Ig in dynamics in the child at 1, 3, 6 and 11-12 months, and when clinical signs of the disease are used, direct detection methods of the pathogen( PCR, Ar detection by the RIF or EIA method).
In some cases, when a newborn is examined for intrauterine infections, a falsely negative serological
result is possible due to the effect of a high concentration of the parent IgG class antibodies that "mask" the presence of ATM Ig in a child, or immunological tolerance( inability of the body to respond to an immune response and AT synthesis).In this regard, in the presence of clinical manifestations of the disease must use methods of direct detection of the pathogen.
Table Interpretation of the results of the laboratory examination of the mother and child
Result of the study
Evaluation and recommendations
The presence of AT in the mother and the child for the same causative agent
Detection of AT in the mother and their absence in the newborn if he has a clinical picture of the disease,as well as for the examination of a child born from an infected mother
Detection of high titers of Ig IgG in a child soon after birth
Detection of a child with AT and / or pathogens( Ag) fromAT utstvii inmother
Specific ATG titre in the child's serum exceeds the titre of analogous ATs in the mother( in the absence of ATM IgM and IgA). The presence of IgM and / or IgA( for chlamydia) in the AT The appearance of IgM and / or IgA( for chlamydia), along with ATIgG or only IgG in a previously seronegative child( seroconversion)
The presence of an IgM AT indicates a congenital infection. If the titre of Ig IgG is elevated, it is necessary to conduct an AT scan in dynamics after 1-2 months. Methods to directly detect the pathogen( PCR, detection of Ar by the RIF or ELISA method)
Use methods of direct pathogen detection( PCR, detection of Ar by the RIF or ELISA method) in a child or to investigate the AT titer in dynamics during the first year of life, sinceinfection can not be ruled out( there may be immunological tolerance when there is no synthesis of AT)
The elevated content of Ig IgG indicates rather the passive immunity received from the mother than about the congenital infection. To clarify the situation, it is necessary to investigate the Ig Ig titer or to monitor the dynamics of the Ig IgG( if the child is not infected, their titer decreases by the age of 4-6 months) Intrauterine infection or infection during labor;possible infection of the child through the mother's milk or with blood transfusions and its components;in some cases, infection is possible with medical staff. The situation is possible for women who have been treated for infection, in case of pregnancy on the background of treatment or in the first months after treatment. Results of the study can not indicate the infection of the child. It is necessary to investigate the AT titer in dynamics and use methods of direct detection of the pathogen( PCR, detection of Ar by the RIF or ELISA method) Evidence of infection of the child( IgM through the placenta does not penetrate) Evidence of primary infection