Cytomegalovirus IgG Antibodies

Detects IgG antibodies to cytomegalovirus.

To detect past exposure to cytomegalovirus.

1. Tell your doctor when your symptoms started or when you may have been exposed to the infection.
2. Fasting is usually not required for blood antibody tests. Tell your doctor when the illness started and about your current treatment.
3. List the medications you take, any immunosuppressive treatment, and previous test results if you have them.
4. If the test is done very soon after a possible infection, discuss with your doctor whether a negative result should be repeated.

Fasting is generally not required. If another test has been ordered at the same time, the overall preparation plan may change.

A specific time is generally not required. If your doctor has set a different time, follow those instructions.

• Time since infection and the antibody development window
• Immune status and some treatments
• Cross-reactions and test specificity

Venous blood — serum or plasma

The blood sample is collected by a qualified staff member. The tube type, required volume, and processing and storage conditions are set by the laboratory's specific method. You do not need to store the sample yourself.

CMV IgG usually indicates past exposure to the virus. A positive or negative result should be interpreted in light of the stage of illness and the accuracy of the test.

If the result is reactive or indeterminate, see a doctor to choose confirmatory testing and next steps. Timely evaluation is especially important during pregnancy.

A positive IgM antibody result alone does not always mean a new infection. During pregnancy, IgG avidity testing, a repeat test or a specialist's assessment may be needed.