How is it used?
Epstein-Barr Virus (EBV) antibodies are used to help diagnose Mono if you are symptomatic but have a negative Mono test. The Centers for Disease Control and Prevention (CDC) recommend ordering:
- Viral capsid antigen (VCA)-IgM, VCA-IgG and D early antigen (EA-D) — to detect a current or recent infection
- VCA-IgG and Epstein Barr nuclear antigen (EBNA) — to detect a previous infection
In pregnant women with symptoms of a viral illness, one or more of these EBV antibodies may be ordered along with tests for CMV, toxoplasmosis, and other infections (sometimes as part of a TORCH screen) to help distinguish between EBV and conditions that may cause similar symptoms. Occasionally, a VCA-IgG or other EBV antibody may be repeated 2-4 weeks after the first test, either to see if a test changes from negative to positive or to measure changes in antibody concentrations to see if they rise or fall.
A VCA-IgG test, and sometimes an EBNA test, may be ordered on an asymptomatic patient to see if that person has been previously exposed to EBV or is susceptible to a primary EBV infection. This is not routinely done, but it may be ordered when a patient, such as an adolescent or an immune compromised patient, has been in close contact with a person who has Mono.
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When is it ordered?
EBV antibodies may be ordered when you have symptoms suggesting Mono, but a negative Mono test and when a pregnant woman has flu-like symptoms and the doctor wants to determine whether the symptoms are due to EBV or another microorganism. Signs and symptoms may include:
- Fatigue
- Fever
- Sore throat
- Swollen lymph glands
- Sometimes enlarged spleen and/or liver
VCA-IgG and EBNA may be ordered whenever your doctor wants to establish previous exposure. Testing may occasionally be repeated when your doctor wants to track antibody concentrations and/or when the first test was negative, but your doctor still suspects that your symptoms are due to EBV.
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What does the test result mean?
If you have positive VCA-IgM antibodies, then it is likely that you have a current, or had a very recent, EBV infection. If you also have symptoms associated with Mono, then it is most likely that you will be diagnosed with Mono, even if your Mono test was negative. If you also have positive VCA-IgG and EA-D IgG concentrations, then it is highly likely that you have, or recently had, an EBV infection.
If the VCA-IgM is negative but the others and an EBNA antibody are positive, then it is likely that you had a previous EBV infection. If you are asymptomatic and are negative for VCA-IgG, then you have not been previously exposed to EBV and are vulnerable to infection. In general, rising VCA-IgG levels tend to indicate an active EBV infection, while falling concentrations tend to indicate a recent EBV infection that is resolving. However, care must be taken with interpreting EBV antibody concentrations as the amount of antibody present does not correlate with the severity of the infection or with the length of time it will last. High levels of VCA-IgG may be present and may persist at that concentration for the rest of your life.
Below, results are provided in table form.
Test results most likely indicate the following:
EBV antibody test
| susceptile to ebv
| current ebv infection
| Past ebv infection
| comments |
| VCA-IgM |
|
+
|
+
|
Appears first, gone in 4-6 weeks
|
| VCA-IgG |
– |
+ |
+ |
If negative susceptible, it appears within a week of infection, then present for life |
| EBNA-IgG |
|
|
+ |
Becomes positive in 2 – 4 months, then present for life |
| EA-D IgG |
|
+ |
+ |
Positive in about a week, usually gone in 2 weeks, persists in 20% of people |
| Heterophile IgM (Mono test) |
|
+ |
|
Associated with Mono, with other conditions, common in children |
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Is there anything else I should know?
There are at least two other antibodies that arise during an EBV infection - an IgA antibody to the EBV viral capsid antigen (EBV VCA-IgA) and an IgG antibody to the EBV early antigen restricted (EA-R IgG). While it is possible to test for these antibodies as part of the EBV diagnostic workup, it is rarely necessary to do so.
The most common complication of Mono is a ruptured spleen. Other complications of EBV infection that can occur include trouble breathing due to a swollen throat, strep throat at the same time, and, rarely, jaundice, skin rashes, pancreatitis, seizures, and/or encephalitis. EBV is also associated with, and may play a role in, several rare forms of cancer, including Burkitt’s lymphoma and nasopharyngeal carcinoma.
Reactivation of the virus is rarely a health concern unless the patient is significantly and persistently immune compromised, as may happen in those who have HIV/AIDS or in those who have received an organ transplant. Primary infections in these patients can be more severe, and some may experience chronic EBV-related symptoms.
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