Cytomegalo Virus (CMV) – IgM Test

What is the Cytomegalo Virus- IgM test?

Cytomegalovirus (CMV) is a very common virus that usually causes no symptoms and only causes mild illness in most cases. It is closely related to viruses that cause chickenpox, herpes simplex, and mononucleosis.

For any healthy adult or a kid, the virus causes no serious problems and its effects are temporary. It can only cause serious issues for an unborn child whose mother has the virus and for people who have weakened immune systems. These include people with AIDS or those who have received an organ transplant and it can lead to the development of ailments like retinitis, hepatitis, colitis, pneumonia or encephalitis. The virus is transmitted through sexual and nonsexual contact with various body secretions.

Statistical reports indicate that 60 to 90% of adults have been infected by the virus at one point in time. The CMV virus can show symptoms right after an infection or it can stay dormant in the body tissues for long periods of time. It can get reactivated from a wide range of stimuli.

The infection is generally free from any specific symptom and most people have developed antibodies from a past infection. In general, most people recover from CMV infection without any complications and do not require antiviral treatment. The infected individual may shed cytomegalovirus in their urine or through the saliva for months. The virus is also excreted through the mucus in the cervix, semen, stool, and breast milk.

– During pregnancy, the virus in the mother’s blood can cross through the placenta and infect the baby.

– Individuals with weakened immune systems can develop the following conditions from CMV.

– Infection in the eyes causing inflammation of the retina, which can lead to blindness.

– Digestive tract problems causing bloody diarrhea and abdominal pain.

– Lung infections, causing pneumonia with a non-productive cough and shortness of breath.

– Encephalitis

– This can result in the further weakening of the immune system, causing secondary infections like fungal infections.

At present, there is no commercially available vaccine for the virus but work for the development of the same is in progress. The CMV antibodies include both IgM and IgG antibodies which are the immune system’s response to a CMV infection. The test is helpful in determining an acute or past infection with the cytomegalovirus. The detected presence of CMV from an IgMis studied in combination with the IgG test results to establish reliable evidence for any primary infection.

Some babies may have congenital CMV infection resulting in health problems that are apparent at birth or may develop later during infancy. In the most severe cases, CMV can cause pregnancy loss. In many babies, the virus can also result in long-term problems which include the following.

– Hearing loss
– Developmental and motor delay
– Vision loss
– Microcephaly (small head)
– Seizures
– Autism
– Cognitive and learning difficulties

In general, 1 out of 5 babies with congenital CMV will have such long-term health problems.

Why do I need to undergo a Cytomegalo Virus- IgM test?

The test is mostly ordered with other tests for pregnant women or patients whose immunity is compromised for some reason. The symptoms, if present at all, maybe similar to the typical flu and include the following.

– Fatigue, weakness
– Sore throat
– Swollen lymph nodes
– Fever
– Headache
– Muscle and joint aches
– Low appetite and weight loss
– Night sweats.

In cases dealing with recurring CMV, the symptoms depend on the organ that has been affected. The test can be ordered for the following symptoms:

– Fever
– Severe Diarrhoea, gastrointestinal ulcerations, and gastrointestinal bleeding.
 – Pneumonia with hypoxemia, or low blood oxygen.
  – Mouth ulcers.
– Various problems with vision, including floaters, blind spots and blurred vision.
  – Hepatitis, or inflamed liver
  – Encephalitis or inflammation of the brain, leading to behavioral changes, seizures, and even coma.

In general, more than 90 percent of babies born with CMV have no symptoms. If any symptoms are present, they may include the following.
– Jaundice
– Red or spots under the skin or a rash
– Enlarged liver and/or spleen
– Low birth weight
– Seizures
– Low platelet count

How is a Cytomegalo Virus- IgM test performed?

For CMV IgM antibody testing, a blood sample is drawn from a vein through a needle and the process is termed as venepuncture. The process very simple and it involves the following steps.

The collection area is disinfected to prevent any infections. The collection site is generally around the elbow region but at times it can also be at the back of the hand.

An elastic band is tied in the upper arm to make the vein swell with blood, thus making the collection process easier.

A needle is inserted into the vein and the required volume of blood is drawn through it in an attached tube. Slight pain or stinging sensation is felt when the needle is inserted.

The needle is withdrawn and the band is loosened to release the pressure on the arm. Some pressure is applied on the site through a gauze or a cotton role to prevent any excess bleeding. The spot is then covered with a sterile bandage and the sample is sent to the laboratory for testing.

The entire process is safe and is generally concluded within a few minutes. Since the size of the veins varies from one person to the other, venipuncture may be difficult for some patients and multiple punctures may be needed.

For infants or young children, veins are difficult to find and hence, a sharp tool called a lancet is often used to break the skin and collect the required volume of blood.  In some exceptional situations, a patient might feel dizzy or lightheaded due to loss of blood after the collection and may need proper care.

Any pain or bruising in and around the collection site is generally cured within a few days. Chances of infection are rare but might happen in exceptional cases and such cases need proper medical attention.

What is the price for a Cytomegalo Virus- IgM test in India? 

The cost of the test varies between Rs 400 to Rs 2000 depending on the location and facilities provided in the testing center.

When will I get the test results?

In general, the test results are generally delivered within 24 to 48 hours, depending on the laboratory.

What is the normal range for a Cytomegalo Virus- IgM test?

The test results are either negative or positive, based on the presence or absence of the IgM antibody in the blood.

What do the results mean?

The test results are interpreted along with clinical findings, patient history, and the signs and symptoms. It is often difficult to differentiate between an active or reactivated CMV infection as a person with weak immunity may not generate sufficient antibodies in response to the virus. The IgM results are interpreted along with CMV IgG results for a better diagnosis. The possible outcomes from the antibody test results are summarized in the following table.

Do I need to fast for the Cytomegalo Virus- IgM test?

Fasting is not necessary before appearing for the test

What else do I need to know before I appear for a Cytomegalo Virus- IgM test?

The following points highlight some of the aspects of the test for a better insight.

Mild cytomegalovirus infection is usually not treated as it gets cured on its own. When the infection gets serious or threatens the eyesight, antiviral drugs are used.

For patients in whom the infection occurs due to a temporarily weakened or suppressed immune system, it generally subsides once the immune system recovers.

In some cases, tests done in the very early stages of an acute infection could turn out to be negative due to undetectable levels of IgM antibodies.

The test for CMV is often conducted as a part of the TORCH testing panel to detect specific infections in pregnant women to prevent any chances of birth defects. These tests generally include the detection of Toxoplasmosis, Rubella, Cytomegalovirus and Herpes simplex virus.

Can pregnant women undergo a Cytomegalo Virus- IgM test?

Pregnant women can undergo the test without any restrictions

Is Cytomegalo Virus- IgM possible for new-born babies?

The test can be conducted on new-born babies as advised by the doctor.