A virus which is commonly found in people of all ages. Once a person gets infected, it stays in your body for life, but a healthy person’s immune system keeps virus from causing illness. It is only in people with weakened immune system & pregnant females where it can cause complexities. While in healthy person it is known to cause mild illness with symptoms like fever, fatigue, sore throat & swollen glands. Newborns with CMV can have lung, brain, spleen, liver & growth problems.
What is CMV IgM Lab Test?
To detect CMV in an individual, CMV IgM testing (antibody testing/serology) is done. This test looks for antibodies (IgG or IgM) in blood samples which are produced by body’s immune system in response to the CMV infection. Here, immunoglobulin M (IgM) antibodies are screened which basically are produced by the body as a first response to CMV infection. IgM levels rise for short period & fall below detectable levels after a few months. They may rise again when latent (infectious agent present but not causing symptoms) CMV is reactivated.
Why is CMV IgM Lab test done?
This test is done to diagnose recent infection (primary, reactivation, or reinfection) in cases like:
Immune-compromised patients & pregnant females with symptoms of CMV infection
People receiving bone marrow or organ transplant
Infants with congenital (birth) abnormalities
Firstly, blood sample is drawn from vein.
Then these samples are sent to the laboratory
These samples then undergo serologic (antibody) testing. It will detect IgM antibodies which are produced immediately upon first exposure to infection and are traceable for short period of time.
Healthcare professionals compare presence or absence of IgG & IgM antibodies from same samples collected 1 to 3 months apart (acute= samples taken at a time when patient initially exhibits signs & symptoms of a disease, convalescent= samples taken at a time when a patient is recovering from a disease) to differentiate b/w active & latent(dormant) CMV.
What is the purpose behind CMV blood test?
Cytomegalovirus infection is a condition caused by type of herpes virus. The CMV blood test is used to detect current active CMV infection, or past infection in people with risk of reactivation of CMV infection.
What will happen if my results come CMV positive?
In people with IgG & IgM positive results, there is active infection present. Therefore, they are barred from donating till IgM results come negative.
Can CMV be considered an autoimmune disorder?
Yes, human cytomegalovirus is linked to autoimmunity especially in people genetically predisposed towards the disease.
How can you know if CMV is active?
In some cases, symptoms occur which include tiredness/uneasiness, swollen glands, night sweats, fever, muscle & joint pain, sore throat & low appetite.
What is meant by CMV IgM positive?
A positive result shows that recent infection (primary, reactivation or reinfection) is present. Also IgM may show response in secondary CMV infections (reactivation) in CMV mononucleosis, pregnant women (few), & in kidney & cardiac transplant patients.
This test results are given in comparison with both IgM & IgG levels. CMV IgM presence is not considered as primary CMV infection diagnosis as IgM can also increase during secondary CMV infection. So, that’s why IgM positive result together with low IgG result is considered reliable.
INTERPRETATION OF RESULTS:
“Negative” IgM & “Negative” IgG: indicate that patient wasn’t exposed to CMV or its too early
“Positive” IgM & “Negative/Positive” IgG: indicate acute or recent infection
“Negative” IgM & “Positive” IgG: indicate immunity from past exposure is present & there is no acute disease condition.
“Equivocal” results: indicate borderline results and such samples should be again taken & tested after 7 to 14 days.
You get tested to diagnose primary infection due to current or very recently infected CMV. It also detects secondary CMV infections (reactivation) & demonstrated in CMV mononucleosis (illness caused by CMV), pregnant females, kidney & cardiac transplant patients.