Cytomegalovirus (CMV) Tests
Reviewed
Also called: CMV IgG and IgM, cytomegalovirus antibody
Cytomegalovirus (CMV) tests check for signs of CMV in your blood, sputum, or other body fluids. CMV is a common virus that usually stays dormant after infection but can reactivate. Testing helps diagnose a current, reactivated, or past CMV infection in people at risk for health complications, such as those with weakened immune systems, pregnant women, and newborns. There is no cure for CMV, but antiviral medicines and other treatments may reduce symptoms and improve outcomes.
Specimen: Blood, cerebrospinal fluid, sputum, tissue, amniotic fluid, infant saliva, infant urine
Why this test may be ordered
- To diagnose a current, reactivated, or past CMV infection in people at risk for health complications.
- If you have a weakened immune system or are pregnant and have symptoms such as swollen lymph nodes, sore throat, fever, fatigue, weakness, muscle aches, or headache.
- For newborns with symptoms such as jaundice, low birth weight, small head, hearing and/or vision problems, seizures, or rash.
Preparation and collection
No special preparations for a blood or sputum test, or for an infant saliva or urine test. You may need to empty your bladder before a spinal tap. You may be asked to fast for several hours before a biopsy. For an amniocentesis, you may be asked to not urinate before the test (to have a full bladder) or to have an empty bladder in later pregnancy.
Blood draw from a vein in your arm; cerebrospinal fluid via spinal tap; sputum (coughed up or via bronchoscopy); tissue biopsy; amniotic fluid via amniocentesis; infant saliva swab; infant urine collection bag.
Blood test: very little risk; slight pain or bruising at needle site, most symptoms go away quickly. Spinal tap: very little risk; you may feel a pinch or pressure, and afterward some pain, tenderness, bleeding, or a headache that may last several hours to a week or more. Biopsy: little bruising, bleeding, or soreness at the site, usually goes away after a few days. Amniocentesis: some stinging, pressure, and/or cramping during the test; afterward mild discomfort, vaginal bleeding, or a small amount of amniotic fluid leakage; risk of serious complications is extremely low. Sputum test, infant saliva test, infant urine test: no known risks.
Understanding results
The test result can show whether you have ever had a CMV infection. But the tests can't show if it's a current, past, or reactivated infection.
- Positive (antibodies or virus detected): You have ever had a CMV infection (past or current). Limitation: Cannot distinguish current, past, or reactivated infection. Next step: Your provider may do additional tests to help make a diagnosis and create a treatment plan.
- Negative (no antibodies or virus detected): You have never had a CMV infection. Limitation: Cannot distinguish current, past, or reactivated infection. Next step: Your provider may do additional tests to help make a diagnosis and create a treatment plan.
- The test can show whether you have ever had a CMV infection, but it cannot tell if it is a current, past, or reactivated infection.
- If you have symptoms and/or risk factors such as an immune system disorder, your provider may do additional tests to help make a diagnosis and create a treatment plan.
What to do next
If you have questions about your results, talk to your provider or your child's provider.
- What do my results mean for my health or my baby's health?
- Do I need any additional tests to confirm or clarify the result?
- What follow-up care or monitoring is recommended based on my results?
Evidence source
U.S. National Library of Medicine: Cytomegalovirus (CMV) Tests