Cytomegalovirus infection

Last updated: March 23, 2023

Summarytoggle arrow icon

Infection with the cytomegalovirus (CMV or human herpes virus 5) is generally asymptomatic in immunocompetent hosts, but can cause mild mononucleosis-like symptoms. Like all Herpesviridae infections, CMV persists for the lifetime of its host; reactivation may therefore occur. Immunocompromised individuals (e.g., AIDS, post-transplantation) are especially at risk of illness following reactivation or initial infection, which can include severe manifestations such as CMV retinitis (risk of blindness) or life-threatening CMV pneumonia. Treatment with ganciclovir or valganciclovir should therefore begin promptly on clinical suspicion of a CMV infection.

Congenital CMV infection is discussed in another article.

Epidemiologytoggle arrow icon

  • Prevalence of CMV infection in the general population: 40–100%
  • Seroprevalence increases with age with more than 90% in individuals > 80 years

Epidemiological data refers to the US, unless otherwise specified.

Etiologytoggle arrow icon


Pathophysiologytoggle arrow icon

  • CMV binds to integrins; activation of integrins induction of cellular morphological changes → activation of signal transduction pathways; such as FAK (focal adhesion kinase) and apoptotic pathways → cell damage clinical manifestations depending on the organ/tissue affected. [4][5]
  • After primary infection resolves, CMV remains latent in mononuclear cells (e.g., myeloid cells). Reactivation can occur if the patient becomes immunocompromised. [6]

Clinical featurestoggle arrow icon

CMV infection is usually asymptomatic. Severe manifestations occur in immunocompromised states (e.g., following organ transplantation, AIDS).

For information about congenital CMV infection, see the corresponding article.

In immunocompetent patients

In immunocompromised patients

One or more of the following clinical manifestations may be present:

Among HIV-positive patients, manifestations of CMV disease usually occur when the CD4 count is ≤ 50!

Diagnosticstoggle arrow icon

In immunocompetent patients, CMV infection may present similarly to EBV infection. However, in CMV infection the monospot test will be negative!

Serological tests may be unreliable in immunosuppressed patients!

Treatmenttoggle arrow icon

CMV infection Regimen Duration
CMV retinitis
  • At least 3–6 months
CMV colitis
  • 21–42 days
CMV esophagitis
CMV pneumonia
  • Until CD4 count > 100 cells/mm3 and symptoms improve
CMV encephalitis

Referencestoggle arrow icon

  1. Feire AL, Koss H, Compton T. Cellular integrins function as entry receptors for human cytomegalovirus via a highly conserved disintegrin-like domain. Proceedings of the National Academy of Sciences. 2004; 101 (43): p.15470-15475.doi: 10.1073/pnas.0406821101 . | Open in Read by QxMD
  2. Poncet D, Pauleau A-L, Szabadkai G, et al. Cytopathic effects of the cytomegalovirus-encoded apoptosis inhibitory protein vMIA. J Cell Biol. 2006; 174 (7): p.985-996.doi: 10.1083/jcb.200604069 . | Open in Read by QxMD
  3. Cytomegalovirus. Updated: January 1, 2020. Accessed: July 3, 2020.
  4. Wingard JR. Overview of infections following hematopoietic cell transplantation. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. Last updated: January 10, 2017. Accessed: October 3, 2017.
  5. Cytomegalovirus (CMV) and Congenital CMV Infection. Updated: August 23, 2016. Accessed: January 5, 2017.
  6. Friel TJ. Epidemiology, clinical manifestations, and treatment of cytomegalovirus infection in immunocompetent adults. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. Last updated: October 28, 2015. Accessed: January 5, 2017.
  7. Akhter K. Cytomegalovirus. In: Bronze MS, Cytomegalovirus. New York, NY: WebMD. Updated: August 12, 2015. Accessed: January 5, 2017.
  8. Cytomegalovirus. Updated: February 1, 2003. Accessed: January 5, 2017.
  9. Tan BH. Cytomegalovirus treatment. Curr Treat Options Infect Dis. 2014; 6 (3): p.256-270.doi: 10.1007/s40506-014-0021-5 . | Open in Read by QxMD
  10. CMV Retinitis. Updated: April 27, 2016. Accessed: January 5, 2017.
  11. Guidelines for Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents. Updated: November 4, 2015. Accessed: January 22, 2017.
  12. Eledrisi MS, Verghese AC. Adrenal insufficiency in HIV infection: a review and recommendations. The American Journal of the Medical Sciences. 2001; 321 (2): p.137-144.

Icon of a lock3 free articles remaining

You have 3 free member-only articles left this month. Sign up and get unlimited access.
 Evidence-based content, created and peer-reviewed by physicians. Read the disclaimer