CMV Diagnostic (anti-CMV IgG & IgM)

Reporting Name

Useful For

Diagnosis of primary, acute phase infection with cytomegalovirus (CMV), especially in patients with infectious mononucleosis and pregnant women who, based on clinical signs or exposure, may have primary CMV infection


Determining whether a patient (especially organ donors, blood donors, and prospective transplant recipients) had CMV infection in the past


Testing Algorithm

Reporting Name Available separately Always performed


Indications for Testing

  • Mononucleosis-like illness in immunocompetent patients
  • Suspected CMV infection based on presentation in immunocompromised patients
  • Congenital syndrome that presents with symptoms of CMV


Method Name

Chemiluminescent microparticle immunoassay (CMIA)


Reporting Name







Cytomegalo Inclusion Disease (CMID)

Torch IgM


Specimen Required

Human serum and plasma (EDTA, heparin or sodium citrate).

If congenital infection is suspected submit maternal serum as well.


Specimen Minimum Volume

0.4 mL



Transport Temperature

Specimen Room temperature Refrigerated Frozen
Serum NO YES* YES**
Plasma NO YES* YES**

*The samples should be stored for not more than 14 days at 2-8°C.

**For longer delay, freeze at -10°C or colder.


Reject Due To

Specimens other than Serum and plasma
Anticoagulants EDTA, Sodium Citrate, Lithium Heparin, Sodium Heparin
Hemolysis Mild OK, Gross REJECT
Lipemia Mild OK, Gross REJECT
Icteric OK

Useful For

Diagnosis of primary, acute phase infection with cytomegalovirus (CMV), especially in patients with infectious mononucleosis and pregnant women who, based on clinical signs or exposure, may have primary CMV infection



Clinical Information

Cytomegalovirus (CMV) is a significant cause of morbidity and mortality, especially in organ transplant recipients and individuals with AIDS. CMV is also responsible for congenital disease of the newborn. The most common infections with CMV in immunocompromised hosts result from reactivation of the virus (latent) from a previous infection, transmission of the virus from a donor organ or blood product, or initial or primary contact with the virus in a seronegative patient. Infection in immunologically normal patients can cause mononucleosis similar to that produced by infection with Epstein-Barr virus.


Infections with cytomegalovirus (CMV), a member of the herpesvirus family, are common in humans and are usually mild and asymptomatic; however, infection in pregnant women, newborns, and immunocompromised individuals may pose a significant medical risk. In utero infection may result in sequelae of varying degree including mental retardation, choriorentinitis, hearing loss and neurologic problems. An individual may undergo primary infection with CMV, reinfection with exogenous virus or reactivation of latent virus.


The presence of CMV specific IgG antibody does not assure protection from disease. The renal transplant patient with primary infection develops significantly more viremia and symptomatic diseases than does the patient with recurrent infection. The provision of seronegative blood products to selected patients remains a vital consideration in patient management. Serologic tests can be used to identify seronegative individuals and seronegative donors of organs or blood products.


CMV acquisition in infants can occur transplacentally following maternal infection, during birth by contact with the virus excreted from the cervix or following birth through the ingestion of infected maternal breast milk. Both seronegative individuals and infants may acquire CMV through infected blood products or contact with an infected individual. Children beyond the neonatal period are susceptible to infection and subsequent transmission of CMV when in day care. CMV has been isolated from contaminated environmental surfaces; however, the role of fomites in CMV transmission has not been established.


Reference Values





CMV IgM CMV IgG Interpretation
REACTIVE NONREACTIVE Recent infection (primary, reactivation, or reinfection)
REACTIVE REACTIVE Current CMV infection/reactivation/reinfection.
NONREACTIVE NONREACTIVE No prior exposure to CMV and, therefore susceptibility to primary infection.


A history of seroconversion from NEGATIVE to POSITIVE IgG is diagnostic of primary infection and may be beneficial in evaluating a pregnant woman with symptoms of viral disease.

Whenever possible, serological diagnosis of CMV infection should be confirmed by other virologic methods such as viral culture.


Clinical Reference

Crumpacker II, C. S., and Zhang, J. L. 2010. Cytomegalovirus, p. 1971-1987. In Mandell, D., Bennett, J. E., and Dolin, R. Principles and practice of infectious diseases, 7th ed., vol. 2. Churchill Livingstone, Elsevier, Philadelphia, PA.


Hodinka, R. L. 2007. Human Cytomegalovirus, p. 1549-1563. In Murray, P. R., Baron, E. J., Jorgensen, J. H., Landry, M. L., and Pfaller, M. A. Manual of Clinical Microbiology, 9th ed., vol. 2. ASM Press, American Society for Microbiology, Washington, DC.


Abbott. 2007. Architect System CMV IgM Package insert. Abbott Ireland, Diagnostics Division, Sligo, Ireland.


Abbott. 2008. Architect System CMV IgG Package insert. Abbott Ireland, Diagnostics Division, Sligo, Ireland.


Status Days Analytic Time Maximum Laboratory Time Specimen Retention
Routine Tuesday, Friday 7h 72h 1 month


Method Description

The ARCHITECT CMV IgM and IgG assay is a two-step immunoassay for the qualitative detection of IgM and IgG antibodies in human serum and plasma. In the first step, sample, assay diluent, and coated paramagnetic microparticles are combined. Anti-CMV IgM/IgG present in the sample binds to the CMV virus lysate (strain AD169) and recombinant CMV antigen coated microparticles. After washing, anti-human IgM/IgG acridinium-labeled conjugate is added to create a reaction mixture. Following another wash cycle, pretrigger and trigger solutions are added to the reaction mixture. The resulting chemiluminescent reaction is measured as relative light units (RLUs). The presence or absence of anti-CMV IgM/IgG in the sample is determined by comparing the chemiluminescent signal in the reaction to the cutoff signal determined from a previous calibration. If the chemiluminescent signal in the specimen is greater than or equal to the cutoff signal, the sample is considered reactive for anti-CMV IgM/IgG.


Performing Laboratory Location

Newfoundland & Labrador Public Health Laboratory

St. John’s


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