Cytomegalovirus (CMV)

November 28, 2023

Cytomegalovirus (CMV) is a common virus belonging to the family Herpesviridae. It is a ubiquitous virus that infects people of all ages. CMV is spread through body fluids such as blood, saliva, urine, and breast milk.

What are the symptoms of cytomegalovirus infection?

Most healthy individuals who become infected with CMV have no symptoms and the virus remains dormant in their body. However, for people with weakened immune systems, such as newborns, the elderly, and people with HIV/AIDS, CMV infection can cause severe symptoms such as fever, fatigue, and swollen glands.

What medical conditions are associated with cytomegalovirus?

In healthy people, CMV usually causes no symptoms as the immune system keeps the virus under control (this is described as dormant). However, in people with weakened immune systems, such as those with HIV/AIDS, transplant recipients, and those undergoing chemotherapy, CMV infection can cause severe complications such as pneumonia, retinitis, encephalitis, hepatitis, and gastrointestinal problems.

CMV infection during pregnancy can also cause congenital CMV, which is when the virus is passed from the mother to the developing fetus. Congenital CMV can cause a range of developmental problems such as hearing loss, vision problems, and developmental delays.

How is cytomegalovirus infection diagnosed?

Several different laboratory tests can be used to diagnose CMV infection.

The most common methods include:

  1. Blood tests: Blood tests are used to detect the presence of CMV antibodies, which the body produces in response to the virus. This test looks for two types of antibodies: IgM and IgG. IgM antibodies are produced early in the infection and are a sign of recent or current infection, while IgG antibodies are produced later and can indicate a past or ongoing infection.
  2. Viral culture: A sample of body fluids, such as blood or urine, is collected and cultured in a laboratory to detect the presence of the virus.
  3. Polymerase chain reaction (PCR): PCR is a technique used to detect the virus’s genetic material in a sample of body fluids, such as blood or urine.
  4. Antigen detection: This test looks for the presence of a specific protein produced by the virus in a sample of body fluids.
  5. Biopsy: In some cases, a biopsy of infected tissue may be necessary to confirm a diagnosis of CMV. The tissue is then examined under the microscope by a pathologist and a test called immunohistochemistry is used to see the virus inside cells.
This picture shows a cell infected by cytomegalovirus.
This picture shows a cell infected by cytomegalovirus.

About this article

This article was written by doctors to help you read and understand your pathology report. Contact us if you have questions about this article or your pathology report. For a complete introduction to your pathology report, read this article.

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