Cytomegalovirus (CMV) Antibodies, IgG
Use
Aid in the determination of serological status to CMV. IgG antibodies rise gradually and persist for the rest of an individual's life. The specific IgG assay is useful in distinguishing who has been exposed to the virus from those who have not. Levels of IgM to hCMV usually increase for some weeks and decrease slowly thereafter, in four to six months. Occasionally, IgM may circulate for years. For the IgM assay, see Cytomegalovirus (CMV) Antibodies, Quantitative, IgM [096727].
Special Instructions
Nucleic acid amplification testing is recommended for the diagnosis of congenital CMV in newborns and for monitoring infection in transplant recipients. IgG avidity assays may help differentiate between primary and past CMV infections. Following primary infection, IgG antibodies show low avidity which increases over months. While commercial assays for avidity testing are available, their results should be interpreted with caution.
Limitations
This assay cannot be used to determine the timing of CMV infection. IgM detection cannot solely diagnose primary CMV infection as IgM can also present in secondary infections or reactivations. Commercial assays for avidity testing are available but require further standardization.
Methodology
Immunoassay (CLIA)
Biomarkers
LOINC Codes
- 5124-3
- 13949-3
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL
Minimum Volume
0.2 mL
Container
Red-top tube or gel-barrier tube
Storage Instructions
Room temperature
Causes for Rejection
Hemolysis; lipemia; gross bacterial contamination
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |
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