OVERVIEW:
What is EBV (Epstein Barr Virus)?
A human herpes virus that is known to cause mild to moderate illness in an individual. This viral infection is very common and is contagious i.e. transmits from person to person via close contact with infected individuals. It is present in saliva so can spread through kissing or sharing utensils/cups with infected person. People get EBV infected mostly during childhood and experience few or no symptoms at all. But if the initial infection occurs during adolescence (puberty), then infectious mononucleosis takes place. Mononucleosis commonly called mono is a condition characterized by fever, fatigue, sore throat, enlarged spleen, swollen lymph nodes, and enlarged liver (sometimes).
What is Anti-EBV IgM lab test?
It is a blood test indicated for diagnosis or identification of EBV infection. It basically detects IgM (immunoglobulin M) antibodies released against EBV virus and helps diagnose the disease. This test helps confirm whether the symptoms during EBV infection is because of a current infection with EBV or not. It also helps in distinguishing among other illnesses and EBV. IgM antibodies levels increase in blood during an active or recent infection and subside after some weeks.
Why is Anti-EBV IgM lab test done?
This test is done:
• As it helps diagnose early, active, or current infection with EBV
• It helps in distinguishing and exclusion of primary EBV infection (i.e. new or recent infection)
• There are 3 parameters which help distinguish b/w acute from past infection which are VCA IgG (viral capsid antigen), VCA IgM, EA (early antigen), & EBV nuclear antigen (EBNA-1 IgG).
• VCA: anti-VCA IgG appears in acute phase of EBV and stays for rest of a person’s life. While anti-VCA IgM appear in early EBV infection and disappear within weeks.
• EA: Anti-EA IgG appear in acute phase of disease and reduces after 3 to 6 months
• EBNA: Anti-EBNA appears after 2 to 4 months of onset of symptoms and persists for life
When To Get Tested?
When you have symptoms of mono but a negative mono test; when a pregnant woman has flu-like symptoms; occasionally when an asymptomatic person has been exposed to someone with mono; or possibly as a means to check immune system function.
- What is EBV IgM test?
When there is presence of VCA IgM antibodies in blood, it indicates a recent primary infection with EBV. If VCA IgG antibodies are present, then it indicates that infection happened sometime in the past.
- Do we always test positive for Epstein- Barr?
Since almost 90% population is known to be EBV infected, so testing positive isn’t important unless you have EBV-like symptoms that cannot be explained by other causes.
- What are complications associated with EBV?
EBV can interact with your genes and increase chances of autoimmune diseases.
- What symptoms arise in chronic Epstein-Barr?
Symptoms like fever, fatigue, lack of appetite, sore throat, rash, or weakness/ soreness in muscles can occur
- What initiates Epstein-Barr infection?
It happens due to close contact with infected person via bodily fluids like saliva.
INTERPRETATION OF THE RESULTS:
When the EBV is suspected but heterophile antibody is not detected, then evaluation of EBV-specific antibody profile takes place which includes VCA IgG, VCA IgM & EBNA. These tests help rule out if the person is susceptible, or has recent/prior infection or reactivated EBV infection:
- VCA IgG (negative), VCA IgM (negative), EBNA IgG (negative) = Interprets no previous exposure
- VCA IgG (positive), VCA IgM (positive), EBNA IgG (negative) = interprets recent infection
- VCA IgG (positive), VCA IgM (negative), EBNA IgG (positive) = interprets past infection
- VCA IgG (positive), VCA IgM (negative), EBNA IgG (negative) = interprets infection with EBV at some point but not clear as to recent or past infection.
- VCA IgG (positive), VCA IgM (positive), EBNA IgG (positive) = interprets past infection
You get tested to distinguish b/w EBV infection and other illness with similar symptoms, to evaluate susceptibility to EBV, when complication of EBV infection is suspected, & b/w primary (new or recent) or past infection.