Cytomegalovirus G positive. CMV Igg positive in pregnancy and newborns

Cytomegalovirus infection is a disease viral etiology directly related to the herpes family. In the case when this disease is in active phase, then it is characteristic inflammatory process salivary glands. and is transmitted through the placental route during pregnancy, through contact and sexual contact, as well as through kissing, during blood transfusions and organ transplant operations.

In medical practice There are also cases of infection of the fetus after passage through the birth canal. In some cases, the disease is asymptomatic during infection. Concerning external signs, then the infection is similar to herpetic rashes on the surface of the skin.

In addition, patients may experience an increase in body temperature. The duration of the disease depends on the degree of its severity, the condition of the body as a whole and immune system. If the disease is not exposed timely treatment, then serious complications may develop. The infection has the peculiarity of manifesting itself not only externally, but also affecting internal organs, and also affecting the state of the nervous system.

This disease is particularly insidious, manifesting itself in hidden form. The danger is that infected person does not feel signs of the disease, as a result of which it is not possible to take timely measures necessary measures. In addition to the source of infection, reduced immunity, as well as the presence of concomitant colds, can contribute to infection.

During diagnostics, affected areas are identified under a microscope. cellular level. It is worth noting that this disease is quite common in almost all countries and is characterized by alternating remissions, when the virus is dormant in the body, and acute recurrent manifestations.

Testing for cytomegalovirus

An IgG analysis for cytomegalovirus is carried out in order to search for specific ones. If we consider the meaning of IgG, deciphering the Latin symbols to understand, what does it mean, then it seems possible to find the following:

• Ig stands for immunoglobulin, which is nothing more than a protective protein compound that can destroy the virus and is produced through the immune system;
• G is one of the classes of immunoglobulins.

In the case when a person is not infected and has never suffered from this infection, then his body does not yet produce antibodies. If the virus is present in the body and CMV igg is positive, then the person is infected.

In this situation, it is very important to understand how immunoglobulins G and M differ.

IgM are rapidly forming immunoglobulins produced by the body for the initial response to infection.

IgG are colonies of antibodies, the formation of which occurs somewhat later. However, they have the ability to maintain the immune system at a certain level for life.

“Ab to cytomegalovirus igg positive” is the wording good result tests, which indicates that the person has already had this disease and the response to the pathogen is a persistently formed immunity.

Cytomegalovirus igg positive

The fact that a person’s infection is progressing is evidenced by the result of an analysis, which makes it possible to track that the cytomegalovirus igg is positive, igm negative indicates that the samples of blood being tested do not contain genetic material, therefore, there is no disease.

In addition, when positive reaction and in the presence of a low IgG index we're talking about specifically about primary infection, the residence time of the virus is no more than 4 months.

To finally make sure that infection is taking place, the patient is prescribed special studies, the main purpose of which is to identify antibodies in the blood. At this stage one of modern methods is PCR.

After infection occurs incubation period, which can vary from 15 to 60 days. It depends on which age category refers to a person, as well as from physiological characteristics his body. The immune system in any case is quite weak and is not particularly durable. Role defensive reaction is caused by the formation of antibodies of the IgM and IgG classes, inhibiting replication at the cellular level.

The degree of disease activity is determined by the quantitative IgM indicator, which makes it possible to establish more accurate diagnosis. A slowdown in the reaction occurs in complex forms of manifestation of this disease, accompanied by severe course. Most often this affects children, pregnant women and people with low immunity.

Positive cytomegalovirus in pregnant women

If iggpositive during pregnancy, then there is a certain probability of transmission of infection to the fetus. Based on the results of specially conducted tests, which can be used to determine what stage the disease is in, the doctor makes a decision on prescribing treatment measures.

The presence of specific IgG indicates that the expectant mother has a functioning immune system, which characterizes the situation as positive. Because otherwise it can be stated that the infection occurred for the first time and precisely during pregnancy. As for the fetus, the disease most likely affected it too.

Positive cytomegalovirus in children

can be expressed in two forms:

• congenital;
• acquired.

The degree of its manifestation, as well as the overall clinical picture. The infection enters the fetus through the placenta. In the case when the infection occurs during pregnancy, the woman’s body lacks antibodies designed to fight the manifestations of this disease.

Cytomegalovirus igg positive in a child often manifests itself immediately after birth, which can be infected not only in utero, but also while passing through the birth canal.

Symptoms of cytomegalovirus in newborns include lethargy, decreased appetite, insufficient sleep and moodiness. Their body temperature often rises, diarrhea may appear, accompanied by constipation, urine darkens, and feces, on the contrary, become light.

In this case, rashes with external signs reminiscent of herpetic manifestations are found on the upper layer of the skin. In almost every case, such children have an enlarged liver and spleen.

The acquired form manifests itself in malaise, weakness, lethargy, apathetic mood and a number of other similar symptoms, accompanied by an increase in body temperature. Sometimes there may be a disturbance in stool, chills, fever, increased The lymph nodes and tonsils.

Who said that curing herpes is difficult?

• Do you suffer from itching and burning in the areas of the rash?
• The sight of blisters does not at all add to your self-confidence...
• And it’s somehow embarrassing, especially if you suffer from genital herpes...
• And for some reason, ointments and medications recommended by doctors are not effective in your case...
• In addition, constant relapses have already become a part of your life...
• And now you are ready to take advantage of any opportunity that will help you get rid of herpes!

An effective remedy from herpes exists. and find out how Elena Makarenko cured herself of genital herpes in 3 days!

Given the extent of the infection, doctors can say with confidence that in 70% of people When conducting a test for cytomegalovirus igg, antibodies were detected, what does this mean, how much of them is contained in the biomaterial, and what is the danger of the virus for children and pregnant women, we will consider in more detail in this article.

What is cytomegalovirus?

Cytomegalovirus is a herpes virus with a latent course upon penetration into the body. Human infection usually occurs up to 12 years, adults cannot become infected with the virus due to the development of stable immunity.

People live and have no idea about the presence of igg in the body, since the action begins only when favorable conditions appear, or a strong decrease in immunity due to:

• organ transplants;
• immunodeficiency, HIV in a patient;
• carried out surgery or long-term use, which have a depressing effect on the immune system.

Cytomegalovirus is especially dangerous for the elderly, children and pregnant women during pregnancy.

Activation of igg antibodies significantly increases the risk of possible intrauterine infection fetus until death. In addition, the baby can catch acquired CMV during breastfeeding, which indicates the reaction of the immune system to the presence and residence of antibodies in the body for more than 3 weeks and exceeding igg norms 3-4 times.

What does a positive test indicate?

igg positive test indicates that a person is a carrier of cytomegalovirus igg, and the immune system expresses its reaction towards them, i.e. is actively fighting. In fact, antibodies to cytomegalovirus are the usual formula for the result of a test for the virus.

If the answer is positive This means that a person has recently been ill with this virus and has developed a stable lifelong immunity to its production, as to the pathogen. Positive result analysis is favorable, unless of course the person suffers from immunodeficiency or AIDS.

The essence of the test

The CMV antibody test is the most exact method blood tests to look for antibodies and the presence of infection.

Each type of pathogen reacts to antibodies in its own way; in an adult there are a great variety of them in the body.

Almost every healthy person is a carrier of antibodies: a, m, d, e.

This means that antibodies to cytomegalovirus are present in the blood in the form of large protein molecules, similar to balls, with the ability to neutralize and destroy viral particles of any type or individual strains.

The body actively fights against any invasion of infection (especially in winter) during the epidemic, acute respiratory infections.

Man reliably protected from a new wave, thanks to a stable immune system. igg positive means that the viral infection was successfully transferred about 1.5 months ago, but in order to avoid getting a cold again, people should not forget to follow simple hygiene measures and preventive procedures.

How is the research conducted?

Virus test is laboratory test blood for the presence or absence of cytomegalovirus strains. Why is a sample taken and the laboratory assistant begins to search for specific antibodies to cytomegalovirus igg in the blood.

It is believed that the degree to which the immune system produces its own specific antibodies or immunoglobulins directly depends on the state of the immune system.

Children and pregnant women are more likely to be affected colds and the identification of a positive iqq due to an unformed immune system and the inability to actively fight the onslaught of viruses.

In adults, a positive test will indicate that the body has previously been affected by cytomegalovirus, but when it resides in blood cells, it is harmless, and the carrier does not even suspect the presence of viruses. Unfortunately, it is completely impossible to get rid of them, but there is no threat to health and there is no need to rush to the pharmacy immediately.

The virus is dangerous only after activation, when the immune system is in a critically suppressed state. The risk group also includes babies under 1 year of age, pregnant women and those infected with HIV. It is the increase in the quantitative indicators of igg in the blood that will indicate the degree of activation of the disease in this moment.

Routes of transmission of the virus

It has always been believed that the main route of transmission of CMV is sexual. Today it has been proven that the virus is transmitted through a kiss, handshakes, shared utensils when it enters the blood through small cracks, cuts and abrasions on the skin.

Exactly like this by everyday means Children are charged after visiting kindergartens and schools and become carriers due to unstable immunity, which is still at the stage of formation.

Children begin to get colds with the appearance of well-known symptoms.

Vitamin deficiency is observed in the blood, which indicates damage to the immune system by viruses, although in adults with CMV there are practically no symptoms.

A positive igg when deviating from the norm leads to symptoms common cold in children:

• runny nose;
• sore throat;
• hoarseness;
• difficulty swallowing;
• increase in temperature;
• enlarged lymph nodes.

The so-called mononucleosis syndrome or cytomegaly is observed with a duration from 7 days to 1.5 months like a common cold.

The special signs include CMV accompanied by respiratory infection it is worth attributing the development of the inflammatory process to salivary glands or genitals (in the testicles and urethra of men or in the uterus or ovaries in women), depending on where the virus is activated.

Cytomegalovirus has a fairly long incubation period, during which the immune system has time to develop stable antibodies in order to prevent the virus from reactivating in the future.

But you should be wary of positive cytomegalovirus igg when testing pregnant women, when transmission of the infection to the fetus and development is quite possible. various kinds anomalies.

A positive igg test indicates primary infection precisely at the time of pregnancy and women, of course, will have to undergo a course of treatment prescribed by a doctor.

Lack of treatment can lead to congenital or acquired CMV in children and with a fairly varied clinical picture depending on the form of infection with the virus.

In case of intrauterine infection or passage through birth canal the baby will inherit a congenital form of cytomegalovirus or acquired - after children visit kindergartens or schools during an epidemic when a large number of children gather. So, symptoms in newborns with the congenital form of CMV:

• lack of appetite;
• moodiness, nervousness;
• lethargy;
• temperature increase;
• constipation;
• darkening of urine;
• stool lightening;
• herpes-type skin rashes;
• enlargement of the liver and spleen.

With the acquired form of CMV, children experience:

• weakness;
• malaise;
• lethargy;
• apathy;
• increased body temperature;
• sleep disturbance;
• fever, chills;
• enlarged lymph nodes and tonsils.

Sometimes the virus occurs completely unnoticed in children. But if symptoms appear, then serious complications and development cannot be avoided: jaundice, inflammatory process in the liver, petechiae on the skin, strabismus, increased sweating at night.

At the first suspicion of an illness, you need to consult a doctor, or call ambulance if the temperature has risen to critical levels. The patient is subject to hospitalization and constant monitoring by doctors to avoid the development of serious complications.

Classes M and G, what are the differences?

1. Antibodies class G They are considered slower, unlike class M, and accumulate in the body gradually in order to maintain the immune defense system and combat provoking factors in the future.
2. Antibodies class M– faster antibodies with immediate production to large volumes, but with subsequent disappearance. They can quickly weaken the provoking effect of viruses on the immune system and lead to the death of the infection at the time of a viral attack.

The conclusion is that primary infection leads to the formation of igg antibodies in the body, followed by the release of immunoglobulins to them. Antibodies of class G will eventually disappear, and only class M antibodies will remain, capable of keeping the disease at bay and preventing it from progressing.

How is the transcript translated?

ELISA is the main indicator of the presence of CMV in the blood. Decoding consists of calculating the number of antibodies and their types to further draw conclusions about the primary or secondary infection of the body.

A positive igg in the blood is a response of the immune system to the level of cytomegalovirus. A negative result will indicate that there has never been any contact with the infection in the person’s life.

For example, the test result - G + and M - indicates a dormant state of antibodies, and groups G-+ and M+ plus - this means that the virus indicators do not exceed the norm and there is no reason for concern.

This test is extremely important for women during pregnancy. And G – and M+ are already a sign of development primary disease in the acute phase. With G+ G+, the disease already takes on a relapsing course, and the immune system is severely suppressed.

The condition is dangerous when a positive cytomegalovirus igm in pregnant women. This means that an inflammatory process and symptoms are occurring in the body: runny nose heat and an increase in the face.

After deciphering the analysis, the doctor will prescribe an index of activity and the number of immunoglobulins as a percentage. So:

• if hCG levels are less than 5-10%, the infection occurred recently and for the first time in the female body;
• the presence of antibodies in 50-60% indicates activation of inflammation;
• the presence of antibodies more than 60% indicates the uncertainty of the situation and the need to repeat the test.

If you want to get pregnant, it is good if before conception the cytomegalovirus igg is detected - positive, and igm - negative. It means that primary infection the fruit will certainly not happen.

If igg and igm are positive, then it is better to postpone pregnancy planning and undergo the treatment prescribed by the gynecologist.

You should be careful about negative igg and igm viruses and do not neglect simple preventive measures.

This means that the virus can be activated at any time, so you need to wash your hands more often, avoid kissing and contact with infected people. strangers, in particular, intimate relationships should be stopped for a while.

In fact, the body must cope with viruses on its own. Treatment with medications is prescribed in the case of:

• immunodeficiency in patients;
• carrying out an organ transplant or a course of chemotherapy that can severely suppress the immune system artificially.

Despite the fact that it is almost impossible to get rid of the virus, when strong immunity he doesn't show himself at all for a long time remains in an inactive state.

What are the symptoms when antibodies are detected?

With an exacerbation of mononucleosis (if the CMV virus does lead to complications), patients develop symptoms similar to a classic cold or sore throat:

• stuffy nose;
• headache;
• increased temperature.

The state of immunodeficiency in newborn babies with a positive igg can lead to:

• jaundice;
• development of hepatitis C;
• indigestion;
• retinitis;
• pneumonia;
• inflammatory processes in the gastrointestinal tract;
• decreased vision;
• diseases of the nervous system;
• encephalitis up to death.

Complications

For example, a prolonged sore throat for more than 5 days can lead to mental or mental complications due to complications. physical abnormalities in children.

The herpes virus is especially dangerous when it infects the fetus during pregnancy and often leads to miscarriages during pregnancy. early stages or mental disabilities in babies at birth.

That is why it is important for women when planning a pregnancy to undergo a test for CMV, in particular, to take medications as prescribed by a doctor:

• Acyclovir, vitamins in the form of group B injections, vitamin and mineral complexes to support immunity;
• Interferon;
• Viferon, Genferon as antiviral agents.

You can fight a cold with home methods:

• , make an oily alcohol tincture;
• add onions and garlic to salads;
• drink silver water;
• brew and drink medicinal fees: wormwood, echinacea, garlic, radiola, violet.

igg virus positive occurs 90% adults. This is normal, but prolonged release of the virus into the blood can lead to immune suppression. Although class G immunoglobulins are actually reliable protectors of our body from the invasion of cytomegalovirus.

A positive test indicates constant protection of the body; with igg + you can live in peace.

It is advisable that life be determined for women who want to conceive a baby in the future, when the likelihood of developing severe defects in the fetus is minimal - no more than 9%, and the activation of the virus is no more than 0 1%.

Cytomegalovirus belongs to the herpes virus family, namely. A blood test for the virus will help detect it.

Cytomegalovirus affects different types of cells:

• salivary glands;
• kidney;
• liver;
• placenta;
• eyes and ears.

But, although the list is impressive, in most cases cytomegalovirus is not dangerous to human health!

What is the danger of cytomegalovirus?

• hearing loss;
• impairment or even loss of vision;
• mental retardation;
• the occurrence of seizures.

Such consequences can occur both during the primary infection and during activation. You just need to remember the likelihood of such serious consequences occurring.

In an infant who became infected during pregnancy, the following external manifestations of cytomegalovirus infection are possible:

• intracerebral calcifications;
• ventriculomegaly (enlarged lateral ventricles of the brain);
• the liver and spleen are enlarged;
• excess fluid occurs in the peritoneum and chest cavity;
• microcephaly (small head);
• petechiae (small hemorrhages on the skin);
• jaundice.

What is analysis on igg?

If the igg is positive, this is evidence that the patient has developed immunity to the virus, but at the same time the person is its carrier.

This does not mean that cytomegalovirus is active or that the patient is in danger. The primary role will be played physical state and the patient's immunity.

Most important It has positive test for a pregnant woman, since the baby’s body is still developing and does not produce antibodies to cytomegalovirus.

During the cytomegalovirus igg study, samples are taken from the patient's body to find specific antibodies to the cytomegalovirus igg. Igg is an abbreviation for Latin word"immunoglobulin".

This is a type of protective protein produced by the immune system to fight the virus.

The immune system begins to produce special antibodies for each new virus that appears in the body.

As a result, upon reaching , a person may already possess a whole “bouquet” of such substances. The letter G denotes a certain class of immunoglobulins, marked in humans with the letters A, D, E, G, M.

Thus, a body that has not yet encountered the virus is unable to produce antiviral antibodies. This is why the presence of antibodies in humans indicates that before the body was already exposed to the virus.

Please note: antibodies of the same type, which are designed to fight different viruses, have significant differences. This is why the results of cytomegalovirus tests on igg are quite accurate.

How is the analysis deciphered?

An important feature of cytomegalovirus is that after the initial damage to the body, it remains in it forever. No treatment will help get rid of its presence.

The virus functions virtually without harm during internal organs, blood and in the salivary glands, and its carriers do not even suspect that they are carriers of the virus.

What are the differences between immunoglobulins M and G?

Igm combines fast “large” antibodies produced by the body in order to respond to the virus as soon as possible.

Igm do not provide immunological memory, dying off within six months, and the protection that they are supposed to provide is eliminated.

igg refers to antibodies that the body clones from the moment they appear. This is done with the aim of maintaining protection against a particular virus throughout a person's life.

These cytomegalovirus antibodies are smaller in size and have a later production time. Typically, they are produced from igm antibodies after the infection has been suppressed.

That is why, having detected cytomegalovirus igm in the blood, which reacts to , it can be argued that the person became infected with the virus relatively recently and at the moment there may be an exacerbation of infection.

To get more full information, additional research indicators need to be studied.

Antibodies to cytomegalovirus igg

What additional tests can be done?

It may consist not only of information about cytomegalovirus, but also carry other necessary data. Specialists interpret the data and prescribe treatment.

To better understand the values, it is worth familiarizing yourself with the laboratory test indicators:

1. Іgg– , igm+: specific igm antibodies were found in the body. With a high degree of probability, the infection occurred recently, and now there is an exacerbation of the disease;
2. igg+, igm– means: the disease is inactive, although the infection occurred a long time ago. Since immunity has already developed, virus particles that re-enter the body are quickly destroyed;
3. igg– , igm– – evidence of a lack of immunity to cytomegalovirus, since this virus has not yet been recognized by the body;
4. igg+, igm+ – evidence of reactivation of cytomegalovirus and exacerbation of infection.

Another important indicator is called immunomodulins:

• below 50% is evidence of primary infection;
• 50 – 60% – the result is uncertain. The analysis should be repeated after 3 - 4 weeks;
• over 60% – there is immunity to the virus, although the person is a carrier or the disease has become chronic;
• 0 or negative result– the body is not infected.

If a person does not have immune system diseases, a positive one should not be a cause for concern.

At any stage of the disease, good immunity is a guarantee of an imperceptible and asymptomatic course of the disease.

Only occasionally does cytomegalovirus manifest itself with the following symptoms:

• general malaise.

It is important to remember that intense and aggravated infection, even in the absence of external signs, is recommended to reduce your activity for several weeks:

• appear less often in public places;
• communicate as little as possible with children and pregnant women.

At this stage, the virus is actively spreading, capable of infecting another person and requiring serious treatment for cytomegalovirus.

?

The greatest danger to the fetus occurs when the virus enters the female body during pregnancy. The danger increases if a woman becomes infected for the first time and is between 4 and 22 weeks pregnant.

If we are talking about reactivation of cytomegalovirus during pregnancy, the risk of infection for the fetus is minimal, but during pregnancy cytomegalovirus infection can lead to the following consequences:

• birth of a mentally retarded child;
• The baby develops seizures, hearing or vision loss.

But don't panic: tragic consequences cytomegalovirus are registered in 9% of cases with primary cytomegalovirus infection and 0.1% with re-infection.

Thus, the vast majority of women with such an infection give birth to healthy children!

Situations typical for pregnant women:

1. If, even before pregnancy, a blood test showed antibodies to cytomegalovirus), then such a woman will never have a primary infection during pregnancy, since it has already occurred in the past - this is evidenced by antibodies in the blood.
2. A blood test for antibodies was taken for the first time during pregnancy and antibodies to the virus were detected. In such cases, reactivation of the infection may occur during pregnancy, and the probability of serious damage to the fetus is 0.1%.
3. The blood test was taken before pregnancy. The woman did not have antibodies to cytomegalovirus (igg-, CMV igm-).

Based on others medical publications, it can be argued: unfortunately, in domestic medicine, everything bad that happens to a child is usually attributed to cytomegalovirus infection.

Therefore, they are appointed repeat tests for CMV IgG and CMV IgM, as well as PCR test for CMV mucus from the cervix.

Given the evidence of constant levels of CMV igg and the absence of CMV igg in the cervix, it can be safely denied that possible complications pregnancies are caused by cytomegalovirus.

Treatment of cytomegalovirus infection

It should be emphasized: none of the available treatment methods completely eliminates the virus.

If cytomegalovirus is asymptomatic, women with normal immunity do not need treatment.

Therefore, even if cytomegalovirus or antibodies to it were detected in a patient with good immunity, there are no indications for treatment.

Efficiency of use, polyoxidonium, etc. is not a panacea.

It can be argued: immunotherapy for cytomegalovirus infection, as a rule, is driven not so much by medical as by commercial considerations.

Treatment of cytomegalovirus in people with weakened immune systems is reduced to the use of (ganciclovir, foscarnet, cidofovir).

Cytomegalovirus penetrates the child’s cells immediately, remaining there for life, existing in an inactive state.

Children aged 2–6 months are infected with virtually no symptoms or any serious problems for good health.

But if a child becomes infected in the first months of life, infection can provoke a real tragedy.

We are talking about congenital infection, when the child became infected in the mother’s stomach during childbirth.

Which children are more dangerous from the virus?

• children who have not yet been born become infected during intrauterine development;
• with a weakened immune system;
• children of all ages with weakened or absent immunity.

Congenital infection with cytomegalovirus carries the risk of affecting the child with serious damage to the nerves, digestive system, blood vessels and musculoskeletal system.

There is a possibility of irreversible damage to the organs of hearing and vision.

Diagnosed using laboratory analysis. Enzyme immunoassay is widely used in the Russian Federation today.

Preventive measures

Using condoms reduces the risk of acquiring infection during sexual intercourse.

To the owners congenital infection you should avoid random intimate relationships during pregnancy.

Cytomegalovirus, IgM

Antibodies of the IgM class to cytomegalovirus are specific immunoglobulins produced in the human body in acute period cytomegalovirus infection and are an early serological marker of this disease.

Synonyms Russian

Antibodies of the IgM class to cytomegalovirus (CMV).

English synonyms

Anti-CMV-IgM, CMV Antibody, IgM.

Research method

Electrochemiluminescent immunoassay (ECLIA).

What biomaterial can be used for research?

Venous, capillary blood.

How to properly prepare for research?

Do not smoke for 30 minutes before the test.

General information about the study

Cytomegalovirus (CMV) belongs to the herpes virus family. Just like other representatives of this group, it can persist in a person throughout his life. U healthy people with normal immunity, the primary infection occurs without complications (and is often asymptomatic). However, cytomegalovirus is dangerous during pregnancy (for the child) and during immunodeficiency.

Cytomegalovirus can be contracted through various biological fluids: saliva, urine, sperm, blood. In addition, it is transmitted from mother to child (during pregnancy, childbirth or breastfeeding).

As a rule, cytomegalovirus infection is asymptomatic. Sometimes the disease resembles Infectious mononucleosis: temperature rises, sore throat, lymph nodes enlarge. The virus then remains inside the cells in an inactive state. But if the body is weakened, the virus will begin to multiply again.

It is important for a woman to know whether she has been infected with CMV in the past because this is what determines whether she is at risk for pregnancy complications. If she has already been infected before, then the risk is minimal. Exacerbation may occur during pregnancy old infection, however, this form usually does not cause severe consequences.

If a woman has not yet had CMV, then she is at risk and should be given Special attention prevention of cytomegalovirus infection. It is the infection that the mother contracted for the first time during pregnancy that is dangerous for the child.

During a primary infection in a pregnant woman, the virus often enters the child’s body. This does not mean that he will get sick. As a rule, CMV infection is asymptomatic. However, in approximately 10% of cases it leads to congenital pathologies: microcephaly, cerebral calcification, rash and enlargement of the spleen and liver. This is often accompanied by a decrease in intelligence and deafness, and even death is possible.

Thus, it is important for the expectant mother to know whether she has been infected with CMV in the past. If so, then the risk of complications due to possible CMV becomes negligible. If not, you need to take special care during pregnancy:

• avoid unprotected sex,
• do not come into contact with another person’s saliva (do not kiss, do not share dishes, toothbrushes, etc.),
• observe the rules of hygiene when playing with children (wash your hands if saliva or urine gets on them),
• get tested for CMV if there are signs of general malaise.

In addition, cytomegalovirus is dangerous if the immune system is weakened (for example, due to immunosuppressants or HIV). In AIDS, CMV is severe and is common cause death of patients.

The main symptoms of cytomegalovirus:

• inflammation of the retina (which can lead to blindness),
• colitis (inflammation of the colon),
• esophagitis (inflammation of the esophagus),
• neurological disorders(encephalitis, etc.).

The production of antibodies is one of the ways to combat viral infection. There are several classes of antibodies (IgG, IgM, IgA, etc.), which differ in their functions.

Immunoglobulin M (IgM) usually appears first in the blood (earlier than other types of antibodies). Then their number gradually decreases (this process can last several months). If an exacerbation of a latent infection occurs, the IgM level will increase again.

Thus, IgM is detected:

• during primary infection (in this case the IgM level is highest),
• during exacerbation of the disease (as well as during reinfection, i.e. infection new form virus).

What is the research used for?

For the diagnosis of acute cytomegalovirus infection.

When is the study scheduled?

• During pregnancy.
• With immunodeficiency (in particular, with HIV infection).
• When a person with normal immunity has symptoms of mononucleosis (if tests do not reveal the Epstein-Barr virus).
• If CMV infection is suspected in newborns.
• During pregnancy:
  • for symptoms of the disease,
  • if ultrasound reveals fetal developmental abnormalities,
  • for screening.

CMV infection in pregnant women is often asymptomatic. However, in some cases, the temperature rises, the lymph nodes, liver and/or spleen become enlarged.

In case of immunodeficiency, the symptoms of CMV infection can be quite varied: from general malaise to retinitis, colitis, encephalitis, etc.

• A test may be prescribed for a newborn if the child:
  • jaundice, anemia,
  • enlarged spleen and/or liver,
  • head size is smaller than normal,
  • have hearing or vision impairments,
  • there are neurological disorders (mental retardation, convulsions).

What do the results mean?

Reference values

Result: negative.

S/CO ratio (signal/cutoff): 0 - 0.7.

Negative result

• There is currently no current CMV infection. If there are symptoms of a certain disease, then they are caused by another pathogen. In this case, CMV may be present in a latent form. However, if the infection occurred quite recently (several days ago), then IgM antibodies may not have had time to appear in the blood yet.

Positive result

• Recent infection (primary infection). During a primary infection, the IgM level is higher than during an exacerbation.

  After the primary infection, IgM can be detected for several months.

• Exacerbation of latent infection.

Important Notes

• Sometimes you need to find out whether a newborn baby is infected with cytomegalovirus. For this purpose, PCR is used and antibodies are additionally determined. If IgM is detected in the child’s blood, it means that he is truly infected with CMV.
• What is reinfection? There are several varieties of CMV in nature. Therefore, it is possible that a person already infected with one type of virus becomes infected with another.

Who orders the study?

Doctor general practice, therapist, infectious disease specialist, gynecologist.

Literature

• Adler S. P. Screening for Cytomegalovirus during Pregnancy. Infect Dis Obstet Gynecol. 2011:1-9.
• Goldman's Cecil Medicine. 24th ed. Goldman L, Schafer A.I., eds. Saunders Elsevier; 2011.
• Lazzarotto T. et al. Why is cytomegalovirus the most frequent cause of congenital infection? Expert Rev Anti Infect Ther. 2011; 9(10): 841–843.

Methods for laboratory diagnosis of cytomegalovirus infection (CMV infection) also include carrying out serological reactions, the purpose of which is to detect antibodies to cytomegalovirus (CMV) or its antigens in the blood of the subject or in other substrates (urine, cerebrospinal fluid, saliva, washings from the trachea and bronchi , smears from the urethra and vagina).

The detection of antibodies in blood serum is based on the fact that in the laboratory (as well as in the body) they strive to contact the antigen of the pathogen to inactivate it.

Thus, if in the laboratory there are reagents containing a cytomegalovirus antigen labeled in some way, then, using them to bind to immunoglobulins in the blood serum, it is possible to calculate the antibody titer by the number of “spent” antigens. This is how direct methods of specific diagnostics work.

Indirect (indirect) methods for diagnosing CMV infection are used less frequently.

To perform the analysis, preliminary preparation is non-specific:

1. On an empty stomach (in order to prevent rapid blood clotting (the minimum fasting period is 4 hours)).
2. Better before 11 o'clock.
3. Do not drink alcohol the night before the test.
4. It is advisable not to smoke on the day of the test.

What serological tests are used to detect antibodies to CMV

The following methods can be used to detect antibodies to cytomegalovirus:

• complement fixation reaction (CFR);
• immunofluorescence reaction (RIF);
• enzyme immunoassay (ELISA);
• solid phase radiological analysis;
• immunoblotting.

The last three types of serological reactions have the greatest specificity and sensitivity, and therefore are used much more often than others. We will not describe the mechanism of action of each reaction; the main thing about them is that they are all aimed at identifying immunoglobulins of class M, G and determining their avidity index.

Immunoglobulins class M (anti-CMV-IgM) in large quantities are formed during the primary immune response (the body’s response to an infectious agent (or one of the serotypes) that first entered the body and caused the disease).

Class G immunoglobulins (anti-CMV-IgG) are synthesized after IgM, causing “immune memory” in relation to a specific serotype of the infectious agent. When re-infected with the same microorganism (same serotype), the human immune system reacts by producing IgG in large quantities.

Next, it is necessary to decipher the concept of the avidity index of antibodies to cytomegalovirus, as well as its significance in the laboratory diagnosis of this infection. Avidity is the ability of immunoglobulins to bind tightly to CMV antigens. And the avidity index (AI) is an indicator that characterizes the degree of strength of the bond between antibody and antigen. Speaking about CMV infection, to clarify the degree of its activity, the avidity index of class G immunoglobulins (anti-CMV-IgG) is used. IgM avidity is not determined.

Interpretation of examination results

1. If class M immunoglobulins (anti-CMV-IgM) are detected in the blood serum in any titer (they also say: IgM to cytomegalovirus is positive), then the patient being examined is diagnosed with a primary cytomegalovirus infection. Further laboratory diagnostics will be aimed at identifying class G antibodies (anti-CMV-IgG) and the virus itself using PCR and/or DNA hybridization methods.
2. Positive IgG results against cytomegalovirus are assessed differently. The table below details various options positive serological reactions to cytomegalovirus.
3. To prevent overdiagnosis of CMV infection, the “paired serum method” is often used. Its essence is to determine the levels of IgG and IgM twice with an interval of 2-3 weeks between blood draws. If the quantitative content of immunoglobulins increases 4 times or more, the likelihood of acute (active) CMV infection in the subject is high.
4. Additionally, I would like to point out the fact that quantitative values ​​in a single serum test are not particularly important. As a rule, significant quantitative antibody levels begin at a titer of 1:100 or higher (threshold values ​​may differ among different laboratories).

What diagnostic methods are used to detect CMV antigens

At the end of the material, it should be noted that to verify the diagnosis of CMV infection, it is not enough just to detect antibodies to the virus; it is also important to confirm the presence of individual antigens or cytomegalovirus DNA in the blood (if necessary, in the cerebrospinal fluid). If DNA or antigens are found in saliva or urine, this does not indicate the activity of CMV infection. The main laboratory methods that can confirm the presence of cytomegalovirus antigens (or DNA) are PCR and DNA hybridization.