CMV IgM and IgG (Cytomegalovirus)
Definition
CMV tests detect antibodies and viral markers in the blood (and also in sputum, cerebrospinal fluid or other body fluids):
| Antibody | General meaning |
|---|---|
| IgM | Suggests a new or current infection |
| IgG | Suggests past exposure or chronic infection |
Purpose
For immunocompromised people (HIV, cancer patients), organ transplant recipients, pregnant women with symptoms of CMV infection, and newborns with signs of infection.
Special importance in pregnancy: a pregnant woman can pass the virus to the fetus; in severe cases this can lead to miscarriage or stillbirth.
Results
The test result can show whether a person has had a CMV infection before.
Risks and Limitations
Critical limitation, stated clearly in the source:
The tests cannot show whether the infection is current, past or reactivated.
In other words, a positive CMV result does not tell you when the infection occurred. If symptoms or risk factors are present, additional testing is needed for a definitive diagnosis.