Cytomegalovirus (CMV) Antibody, IgM in Serum
This test measures the presence of Immunoglobulin M (IgM) antibodies against Cytomegalovirus (CMV), a common virus that can affect people of all ages. IgM antibodies are typically produced early in an infection and can help identify recent exposure to CMV.
["IgM antibodies to CMV may indicate a recent infection that your body is actively fighting."]
Key facts at a glance
- LOINC
- 108596-8
- Short code
- CMV DNA Msmt Tiss
- Synonyms
- CMV DNA Msmt Tiss
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may recommend this test if you have symptoms suggestive of CMV infection, such as fever, fatigue, or swollen lymph nodes, especially if you have a weakened immune system. It may also be used during pregnancy to check for CMV exposure in the mother, as CMV can sometimes affect a developing fetus.
What to Expect Before the Test
No special preparation is needed for this blood test. You may have a small needle inserted into a vein in your arm to draw a blood sample. The process usually takes a few minutes and is generally comfortable.
What the Test Results Mean
A positive result for CMV IgM antibodies suggests recent infection. However, false positives can occur, so additional testing or confirmation may be needed. A negative result means you either have never been exposed to CMV or the infection has resolved.
Possible Side Effects or Risks
The most common side effect is a slight bruise, redness, or soreness at the injection site. Rarely, you might experience dizziness or fainting, especially if you have not eaten recently. Most side effects are mild and resolve quickly.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
CMV IgM Antibody
Frequently asked questions
CMV IgM antibodies are important for diagnosing recent CMV infections, particularly in immunocompromised individuals or pregnant women. Early detection can guide treatment decisions and help prevent complications, such as organ damage or severe illness. In pregnancy, identifying CMV exposure allows for monitoring and potential interventions to reduce risks to the fetus.
A positive result indicates recent exposure to CMV, meaning your body is likely fighting the virus at the time of testing. This can help your healthcare provider determine if treatment is needed or if monitoring is required, especially if you have a weakened immune system or are pregnant.
Yes, false positives can happen, though they are less common. This may occur due to cross-reactivity with other viruses or previous exposure to similar antigens. Your healthcare provider may order additional tests or follow-up to confirm the result.
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy