Cytomegalovirus infection

Cytomegalovirus infection, or cytomegaly, is a chronic anthropo nosis disease of viral etiology, characterized by a variety of forms of the pathological process from latent infection to a clinically expressed generalized disease.

ICD-10 codes

• Q25. Cytomegalovirus disease.
• Q27.1. Cytomegalovirus mononucleosis.
• B35.1. Congenital cytomegalovirus infection.
• B20.2. The disease caused by HIV, with manifestations of cytomegalovirus disease.

What causes cytomegalovirus infection?

Cytomegalovirus infection is caused by cytomegalovirus (CMV, human type 5 herpesvirus), which can cause infection of a variety of strengths. Infectious syndrome is similar to infectious mononucleosis, but there is no pronounced pharyngitis. Expressed local manifestations, including retinitis, develop in HIV-infected patients and less often after organ transplantation and in other immunocompromised patients. Severe systemic damage develops in newborns or immunocompromised individuals. For laboratory diagnosis, cultivation, serological tests, biopsy and the determination of antigens or nucleic acids are useful. Ganciclovir and other antiviral drugs are used in severe disease, in particular, retinitis.

Cytomegalovirus is common everywhere. Infected individuals excrete the virus with urine or saliva for many months; the virus is present in biological fluids, blood; donor organs can cause disease in susceptible recipients. Cytomegalovirus infection is transmitted through the placenta, during labor. Among the general population, infection increases with age: 60 to 90% of adults are infected with cytomegalovirus. High infection is observed among groups with a low socioeconomic level.

What are the symptoms of cytomegalovirus infection?

Congenital cytomegalovirus infection can be latent, without consequences; cause a disease manifested by fever, hepatitis, pneumonia and in newborns with severe brain damage; lead to stillbirth or death in the perinatal period.

Acquired cytomegalovirus infection can occur without any symptoms; cause a disease manifested by fever (CMV mononucleosis), hepatitis with an increase in aminotransferases, atypical lymphocytosis similar to infectious mononucleosis and splenomegaly.

Post-perfusion / post-transfusion syndrome can develop within 2-4 weeks after transfusion of blood products infected with cytomegalovirus infection. Develops fever, lasting 2-3 weeks, and CMV-hepatitis.

In immunocompromised patients, cytomegalovirus infection is the main cause of morbidity and mortality.
 
Patients with cytomegalovirus infection (acquired or developed due to activation of a latent pathogen) may have lung, gastrointestinal, CNS, and kidney lesions. After organ transplantation, these complications occur in 50% of cases and are highly lethal. Generalized CMV infection is usually manifested by retinitis, encephalitis, as well as peptic ulcer of the large intestine or esophagus in the terminal stage of AIDS.

How is cytomegalovirus infection diagnosed?

Cytomegalovirus infection is suspected in healthy individuals with mononucleosis-like syndromes; in immunocompromised individuals with lesions of the gastrointestinal tract, CNS, or eye symptoms; in newborns with systemic symptoms. Differential diagnosis of acquired CMV infection includes viral hepatitis and infectious mononucleosis. The absence of pharyngitis and lymphadenopathy, as well as a negative reaction to heterophilic antibodies, are more typical of primary mononucleosis caused by CMV, and not by the Epstein-Barr virus. Serological studies help differentiate cytomegalovirus infection from viral hepatitis. Laboratory confirmation of CMV infection is necessary only in the case of differential diagnosis with other diseases that give a similar clinical picture. CMV can be isolated from urine, other body fluids and tissues. Cytomegalovirus can be released for many months and years after the infection, which is not evidence of an active infection. Seroconversion is indicated by a change in the antibody titer to the cytomegalovirus. Immunocompromised patients often require biopsy, proving CMV-induced pathology; Also useful is PCR, which allows you to determine the viral load. In children, the diagnosis can be confirmed by obtaining a culture of urine.

How is cytomegalovirus infection treated?

In patients with AIDS, the symptoms of retinitis caused by cytomegalovirus are weakened by antiviral drugs. Most patients receive ganciclovir 5 mg / kg iv twice daily for 2-3 weeks or valganciclovir, 900 mg orally 2 times a day for 21 days. If the initial treatment of cytomegalovirus infection is ineffective at least once, a change in the drug should be performed. After the starting dose, the patient should receive maintenance or suppressive therapy with valganciclovir 900 mg orally once a day to stop the progression of the disease. Supportive treatment of cytomegalovirus infection with valganciclovir 5 mg / kg intravenously once a day is useful to prevent relapses. Alternatively, foscarnet can be used in combination or without ganciclovir, at a starting dose of 90 mg / kg intravenously every 12 hours for 2-3 weeks, then switching to maintenance therapy 90-120 mg / kg intravenously once a day. Side effects of intravenous foscarnet are significant and include nephrotoxicity, hypocalcemia, hypomagnesemia, hypokalemia, hyperphosphatemia and CNS damage. Combination therapy with ganciclovir and foscarnet increases the risk of side effects. Treatment of cytomegalovirus infection with sidovir is carried out at a starting dose of 5 mg / kg intravenously once a week for 2 weeks, followed by the administration of the drug once every two weeks (maintenance dose). Efficacy is close to that of ganciclovir or foscarnet. The use of sidovir limits severe side effects, such as kidney failure. To reduce nephrotoxicity should be administered with each dose of probenicide and conduct hydration of the body. It should be remembered that the probenicide itself can cause significant adverse reactions (rash, fever, headache).

For prolonged treatment of patients, ocular implants with ganciclovir can be used. Intraocular injections into the vitreous are useful in the ineffectiveness of other therapeutic measures or in contraindications to them (therapy of despair). Such treatment of cytomegalovirus infection involves the injection of ganciclovir or foscarnet. Potentially, the side effects of this treatment may include retinotoxicity, vitreous hemorrhage, endophthalmitis, retinal detachment, papillary edema, cataract formation. Sidovir can lead to the development of iritis or ocular hypotension. But even with such therapy, patients need systemic use of antiviral drugs to prevent damage to the second eye or outgrowth. In addition, an increase in the level of CD4 + lymphocytes to a level of more than 200 cells / μl in combination with systemic antiretroviral drugs allows limiting the use of ocular implants.

Anti-CMV drugs are used to treat more serious diseases than retinitis, but their effectiveness is much lower than in the treatment of retinitis. Ganciclovir in combination with immunoglobulin is used to treat cytomegalovirus infection of pneumonia in patients who underwent bone marrow transplantation surgery.

Prevention of cytomegalovirus infection is necessary for recipients of solid organs and hematopoietic cells. Apply the same anti-virus drugs.

What is the prognosis of cytomegalovirus infection?

Cytomegalovirus infection has a favorable prognosis provided the early delivery of a diagnosis of cytomegalovirus pneumonia, esophagitis, colitis, retinitis, polyneuropathy and timely initiation of etiotropic therapy. Later, the detection of cytomegalovirus retinal pathology and the development of its extensive lesion lead to a persistent loss of vision or to its complete loss. Cytomegalovirus damage of the lungs, intestines, adrenals, brain and spinal cord can cause disability of patients or lead to death.