Mononucleosis Spot Test

The mononucleosis spot test is conducted to detect two antibodies present in the blood that is proof of infection with the Epstein-Barr virus (EBV).

When Mononucleosis Test is Recommended

The mono test is primarily recommended when someone manifests symptoms that makes a doctor suspect of infectious mononucleosis. These symptoms may often be confused with symptoms of a flu or cold. Some of the common symptoms of mono are:

  • headache
  • fever
  • swollen glands in your neck or armpits
  • sore throat
  • prolong weakness or fatigue

Some people may witness some other symptoms also such as:

  • stomach ache
  • enlarged spleen or liver spleen
  • rashes

The test may be suggested for more times when it is initially not positive but suspicion of mono remains present.

How Mononucleosis Test is Used?

The mono test is done to enable ascertain whether an individual with symptoms of mono has infectious mononucleosis or not. It is often recommended with a complete blood count (CBC). The CBC is facilitated to detect if the number of white blood cells (WBCs) has enhanced and if a prominent number of reactive lymphocytes are present. A strep test may also be suggested along with the mono test to ascertain whether a person’s sore throat is caused by strep throat, a streptococcal infection in place of or in addition to mononucleosis.

How to Prepare for the Mononucleosis Spot Test

No particular preparation is required.

How Mononucleosis Spot Test is Performed

Blood is generally extracted from a vein, most of the time from the inner are of elbow or the back side of the hand. The location of injection is cleaned using germ-killing medicine (antiseptic). The health care provider uses an elastic band on your upper arm for compressing your vein to swell with blood and make the process of detecting vein and drawing blood easy.

Next, the medical specialist will introduce a thin needle into your vein gradually. The blood will be held in a vial or tube which is attached to the needle. The elastic band is taken off your arm once the process of drawing of blood is over.

Once the blood is taken, the needle is also taken out and the puncture location is compressed with cotton ball or bandage for some time to cease bleeding.

How Mononucleosis Spot Test Will Feel

When the needle is inserted for drawing of blood, you may sense moderate pain, or only a prick or stinging feeling. You may feel throbbing centered at the area of the punctured site for a few minutes after the process is over.

Why Mononucleosis Spot Test is Performed

This test is based on some antibodies. It is facilitated to diagnose infectious mononucleosis, an ailment witnessed because of the Epstein-Barr virus (EBV). After 1 week after the beginning of the disorder, many people observe heterophile antibodies. Antibodies grow to its peak in 2-5 weeks and may survive for up to 1 year. However, a limited number of persons with mononucleosis may never observe such antibodies.

Normal Results

When no heterophile antibodies are diagnosed it is considered as normal report.

What Abnormal Results Mean

If someone displays a positive mono test, an enhanced level of white blood cells, reactive lymphocytes, and symptoms of mono, then that person is considered to be diagnosed with infectious mononucleosis. A positive test goes to say heterophile antibodies are present. These are generally a signal of infectious mononucleosis.

On rare cases, false-positive reports may surface in persons having:

  • Hepatitis
  • Rubella
  • Lymphoma or leukemia
  • Systemic lupus erythematosus (SLE)

If signs and reactive lymphocytes are detected but the mono test is not positive, then it may be not the right time to detect the heterophile antibodies or the suffering person may be one of a small section of people who do not produce heterophile antibodies. Tests for other EBV antibodies and a repeat mono test may be recommended to enable confirm or ward off the mononucleosis diagnosis.

Risks Factors Involved with Mononucleosis Spot Test

Because of variation in size of different veins and arteries from one patient to another and from one side of the body to the other obtaining a blood sample from one person may be tougher than from others.

Other risks involved with drawing the blood sample are slight which may encompasses:

  • Excessive bleeding
  • Hematoma (blood collecting under the skin)
  • Fainting or experiencing lightheadedness
  • Infection (a small risk of broken skin any time)


Monospot tests are generally positive in almost 85% of patients suffering with infectious mononucleosis. Positive test results can only be detected after 1-2 weeks into the illness.

Alternative Names

Forssman antibody test; Monospot test; Heterophile agglutination test Heterophile antibody test.