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Cytomegalovirus Antibody, Titration (IgG)

Published: August 9, 2026Updated: August 16, 2026

This test measures the level of antibodies against cytomegalovirus (CMV) in your blood. Antibodies help your immune system recognize and fight infections.

Quick summary

["This test helps determine if you’ve been exposed to CMV and whether your immune response is active."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
22242-2
Short code
Deprecated CMV Ab Titr Ser
Synonyms
Deprecated CMV Ab Titr Ser
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 order this test if you have a weakened immune system (such as from HIV/AIDS, chemotherapy, or organ transplant), are pregnant, or have symptoms like fever, fatigue, or swollen lymph nodes that could indicate an infection. It’s also used to monitor long-term immunity in people at higher risk.

What to Expect Before the Test

No special preparation is needed. A blood sample is drawn from a vein in your arm, similar to other blood tests. The process usually takes a few minutes and may cause a slight pinch or discomfort.

What the Test Results Mean

A positive result means you have detectable CMV antibodies, indicating past exposure. A lower titer (smaller number) suggests a weaker immune response, while a higher titer may indicate recent or ongoing infection. Results are qualitative (not a specific number) and interpreted by your provider.

Common Reasons for Testing

This test is often used to assess immunity in high-risk groups (e.g., transplant recipients, pregnant women, or those with HIV) to prevent or manage CMV-related complications.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: CMV Antibody Titer

Short name

CMV IgG Antibody Titer

Frequently asked questions

What does a positive CMV antibody titer tell me?
A positive result confirms past exposure to CMV, but it doesn’t indicate whether you’re currently infected. If you’re immunocompromised, your provider may recommend further testing (like PCR) to check for active infection.
Why might my titer be lower than expected?
A lower titer could mean your immune system isn’t producing enough antibodies to maintain protection, especially if you’ve had recent illness, treatment (like chemotherapy), or a weakened immune response.
Can this test be used to diagnose active CMV infection?
No, this test alone cannot diagnose active CMV infection. It’s typically used alongside other tests (like viral load or PCR) to assess immunity or monitor treatment responses.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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