Cytomegalovirus infection - Causes, symptoms and treatment. MF.

Cytomegalovirus infection is a disease caused by cytomegalovirus, a virus from the subfamily of herpesviruses, which also includes herpes simplex viruses 1 and 2, varicella zoster virus and herpes zoster, Ebstein-Barr virus and human herpesvirus types 6,7 and 8.

The prevalence of for cytomegalovirus infection of is extremely high. Once penetrated into the body, cytomegalovirus infection does not leave it - most often it exists in a latent form and manifests itself only with a decrease in immunity.

Victims of cytomegalovirus infection become HIV-infected, as well as people who have undergone transplantation of internal organs or bone marrow and taking drugs that suppress the immune response.

However, when a primary infection occurs, an acute infectious disease can occur. Often, the infection occurs during the period of newborns and in early childhood, especially in developing countries, where the prevalence of cytomegalovirus infection among young people is much higher than in developed countries.

The most dangerous form of is the intrauterine form of cytomegalovirus infection , which is typical for children whose mothers underwent primary cytomegalovirus infection during pregnancy. Congenital cytomegalovirus infection often leads to a delay in development, as well as to numerous adverse effects, including retardation of mental development and hearing loss.

How the infection of the cytomegalovirus infection of

occurs. The cytomegalovirus infection of is not very contagious. For its transfer requires a long close communication or multiple contacts.

• Airborne droplets: during conversation, coughing, sneezing, kissing, etc.
• Sexual way: during sexual intercourse, the risk of transmission of the virus is very high, since the virus is secreted with sperm, vaginal and cervical mucus.
• With blood transfusion and its components containing leukocytes.
• From mother to fetus - most often with primary of cytomegalovirus infection of or reactivation of latent infection during pregnancy.

How the virus of cytomegalovirus infection

works The virus enters the blood of a healthy person and causes a pronounced immune response, which consists in the formation of antibodies - specific protective proteins - M-antibodies( Anti-CMV-IgM), as well as the basic protective reaction against viruses-cellular.

Lymphocytes CD 4 and CD 8 have potent activity against cytomegaloviruses. Therefore, when oppression of the cellular immune response, for example, in violation of the formation of CD4 lymphocytes in AIDS, cytomegalovirus infection actively develops and leads to the reactivation of a previously latent infection.

Immunoglobulins M against cytomegalovirus are formed about 4-7 weeks after infection and are in the blood for 16-20 weeks. Detecting them in the blood during these periods may be evidence of a primary cytomegalovirus infection. Immunoglobulins M are then replaced with immunoglobulins G( Anti-CMV-IgG), which are present in the blood to some extent throughout the subsequent life.

In most cases with normal immunity, the cytomegalovirus infection is asymptomatic, although it remains in the body for a long time as a latent infection. Where exactly the virus is stored is unknown, its presence is expected in many organs and tissues.

Cells affected by cytomegalovirus have a characteristic appearance - they increase in size( which determined the name of the virus), and with microscopy they look like an "owl eye".

Even asymptomatic carriers can transmit the virus to uninfected individuals. The exception is the transmission of the virus from the mother to the fetus, which occurs mainly only with an active infectious process, but only 5% of cases lead to congenital cytomegaly; in the remaining neonates, the cytomegalovirus infection also passes asymptomatically.

Mononucleosis-like syndrome

Mononucleosis-like syndrome is the most common form of of cytomegalovirus infection of in individuals with normal immunity who have emerged from the neonatal period. Mononucleosis-like syndrome in clinical manifestations can not be distinguished from infectious mononucleosis, the cause of which is another herpesvirus - the Ebstein-Barr virus.

The incubation period is 20-60 days. The disease proceeds in the form of an influenza-like illness:

• Prolonged high fever, sometimes with chills;
• Severe fatigue, malaise;
• Pain in muscles, joints, headache;
• Sore throat;
• Enlargement of lymph nodes;
• Skin rash, similar to a rash with rubella, is rare, often with ampicillin.

Sometimes a primary cytomegalovirus infection is accompanied by signs of hepatitis-jaundice is rare, but an increase in hepatic enzymes in the blood often occurs.

Mononucleosis-like syndrome is rare( 0-6% of cases) complicated by pneumonia. However, in immunologically healthy people, it proceeds asymptomatically and is detected only with chest X-ray.

The disease lasts for 9-60 days. The majority of patients recover completely, although residual phenomena in the form of weakness and malaise, sometimes enlargement of the lymph nodes, persist for several months. Recurrences of infection, accompanied by fever, malaise, hot flashes, sweating and rarely occur.

Congenital cytomegalovirus infection

Intrauterine infection of the fetus is not always the cause of congenital cytomegaly, in most cases it is asymptomatic, and only 5% of newborns lead to the development of the disease. Congenital cytomegaly occurs in newborns whose mothers have suffered a primary cytomegalovirus infection.

Manifestations of congenital cytomegaly vary widely:

• Petechia - skin rashes, which represent small hemorrhages occur in 60-80% of cases;
• Jaundice;
• Intrauterine growth retardation, prematurity occurs in 30-50% of cases;
• Chorioretinitis - inflammation of the retina, which often leads to a decrease and loss of vision;

Mortality with congenital cytomegalovirus infection is 20-30%.Most surviving children are mentally retarded or poorly heard.

Acquired cytomegalovirus infection in newborns

When infected with cytomegalovirus during labor( during passage of the birth canal) or after birth( with breastfeeding or usual contact), in most cases the infection remains asymptomatic.

However, in some, especially in premature and small infants , the cytomegalovirus infection of is manifested by the development of prolonged pneumonia, which is often accompanied by the concomitant concomitant bacterial infection.

In addition, it is possible to slow down physical development, rash, swollen lymph nodes, hepatitis.

Persons with Weakened Immunity

Persons with weakened immunity include:

• persons with different variants of congenital immunodeficiency.
• persons with acquired immunodeficiency syndrome( AIDS).
• persons who underwent transplantation of internal organs: kidney, heart, liver, lungs, and also bone marrow.

The severity of clinical manifestations depends on the degree of suppression of immunity, but the constant use of immunosuppressants leads to more severe manifestations.

Cytomegalovirus infection after transplantation:

• Especially often cytomegalovirus affects the transplant organs themselves, causing hepatitis of the transplanted liver, pneumonia of the transplanted lungs, etc.
• After bone marrow transplantation, 15-20% of patients develop cytomegalovirus pneumonia, from which 84-88% of patients die.
• The greatest risk of developing cytomegalovirus infection is if the donor is infected and the recipient is not.

Cytomegalovirus infection of in HIV-infected patients:

Cytomegalovirus infection of affects almost all patients with AIDS.

• The onset of infection is usually subacute: fever, malaise, sweating at night, muscle and joint pain
• Pneumonia - coughing, faster breathing
• ulcers of the esophagus, stomach, intestines that can lead to bleeding and rupture of the wall
• Hepatitis
• Encephalitis is an inflammation of the brain substance. May be manifested by AIDS-dementia syndrome or cranial nerve damage, drowsiness, disorientation, nystagmus( rhythmic movements of the eyeballs).
• Ritinitis - inflammation of the retina is a common cause of vision loss in patients with decreased immunity.
• Multiple organ damage is the defeat of virtually all organs by the virus, leading to their dysfunction. Often is the cause of death from cytomegalovirus infection.

Prevention of cytomegalovirus infection

Prevention of of cytomegalovirus infection is advisable in people at risk. These include HIV-infected people, especially AIDS;persons who have undergone transplantation of internal organs;Persons suffering from immunodeficiency as a result of other causes.

Compliance with the rules of personal hygiene, even the most thorough, does not allow to avoid infection with cytomegaloviruses, as the viruses are spread everywhere and transmitted by airborne droplets. Therefore, prevention in patients at risk is carried out by antiviral drugs: ganciclovir, foscarnet, acyclovir.

In addition, to reduce the likelihood of cytomegalovirus infection among recipients of internal organs and bone marrow, careful selection of donors is recommended, taking into account their infection with cytomegalovirus infection.

Diagnosis of cytomegalovirus infection

Laboratory diagnosis of cytomegalovirus infection is based on serological tests - the determination of antibodies specific for cytomegalovirus.

• Immunoglobulins M - Anti - CMV - IgM;

are markers of acute infection: primary cytomegalovirus infection or reactivation of a chronic infection. When high antibody titers are detected in pregnant women, there is a risk of infection of the fetus. Increase only 4-7 weeks after infection. Remain elevated for 16-20 weeks

• Immunoglobulins G-Anti-CMV-IgG;

The titer of this type of immunoglobulin increases already in the period of decreased activity of the infectious process. The presence of Anti - CMV - IgG in the blood indicates only the presence of cytomegalovirus in the body, but does not reflect its activity.

• Polymerase chain reaction;

PCR is based on the determination of DNA virus in the blood or in mucosal cells( in scrapings from the urethral, ​​cervical canals, as well as in saliva, sputum, etc.).It is recommended to perform quantitative PCR reaction, which allows to judge the degree of reproduction of the virus, and therefore, the activity of the inflammatory process.

Treatment of cytomegalovirus infection

Mononucleosis-like syndrome in uncomplicated course of special treatment does not require. Enough traditional treatment, as with a common cold. The main thing is not to forget to drink plenty of fluids.

The drug of choice for the treatment of cytomegalovirus infection in patients at risk is ganciclovir( cymenevene).For treatment, intravenous forms of the drug are used. Tablets are effective only for prevention.

Side effects of ganciclovir:

• Inhibition of the formation of blood cells( neutropenia, anemia, thrombocytopenia).Develops in 40% of cases.
• Diarrhea( 44%), vomiting, loss of appetite.
• Increased temperature( 48% of patients), accompanied by chills, sweating.
• Itching itch.

Warnings:

• Ganciclovir is not used in people without immunity disorders.
• The use of ganciclovir in pregnant women and children is possible only in life-threatening situations.
• It is necessary to adjust the dose in people with impaired renal function.

Foscarnet is also used for treatment, which is considered more effective in patients with HIV infection.

Side effects:

• Electrolyte disorders: a decrease in the blood of potassium and magnesium.
• Ulcers of genital organs.
• Urination disorders.
• Nausea.
• Kidney damage: the drug is nephrotoxic, so in the case of kidney failure, careful use and correction of the dose of the drug is necessary.