Absolute Eosinophil Count Test

What Are Eosinophils?

Eosinophils are a type of white blood cell that aids in the fight against infection. Although the exact function of eosinophils in the body is unknown, they are commonly associated with allergy disorders and infections. They’re made in your bone marrow and subsequently spread throughout your body.

In the immune system, eosinophils do two things: they fight infections and stimulate inflammation, which can help you stay healthy.

What Is Eosinophilia?

A greater than normal amount of these particular cells in the blood or tissue is eosinophilia.

What Is The Eosinophil Count?

White blood cells are one of the most significant components of the human body. They aid in the battle against germs, parasites, and a variety of viruses. Five different types of white blood cells are produced in the human body by the bone marrow.

White blood cells can survive in the bloodstream for several days to a few hours. Eosinophils are a type of white blood cell that is found in various human tissues. These marrows are in charge of ensuring that the body’s white blood cells are regenerated.

When the number of white blood cells in the body rises, it can indicate an infection or illness. If the levels are high, it suggests the body is producing far more white blood cells than is required to combat illnesses.

The eosinophil count is a test that can determine how many eosinophils are present in the body.

Eosinophils are known to play a variety of additional roles, according to research. Almost every system in the human body is reliant on it in some way. They are involved in any inflammatory reaction, especially when it comes to allergies.

Eosinophil Count Preparation

For this test, there is no need to prepare in any way. If you’ve been taking blood-thinning medications or substances, you must tell your doctor, and he may advise you to stop.

Interferon, diet pills, antibiotics, tranquilizers, and laxatives are some of the drugs that might raise the eosinophil count.

Why Is It Necessary To Have An Eosinophil Count?

During a white blood count differential, doctors can occasionally uncover aberrant eosinophil levels. The WBC differential test is usually performed in conjunction with a complete blood count (CBC), which determines the overall percentage of different types of WBCs in the blood.

This test will also reveal whether you have a low or high WBC count, which might change when certain diseases strike. This test will also reveal whether you have a low or high WBC count, which might change when certain diseases strike. This test can also be ordered if your doctor suspects you have one of the following disorders or diseases:

• Severe allergic reactions 

• A drug reaction or

 • Parasitic illnesses


A blood test for eosinophil count is similar to another blood testing.

A healthcare worker may swab the skin with antiseptic and possibly wrap an elastic band around the arm to draw attention to the vein.

The needle will next be inserted into the vein. Blood is frequently drawn from a vein on the front of the elbow by a healthcare expert. When the needle breaches the skin, some patients feel a tiny pinch.

They’ll remove the needle and elastic band once they’ve gathered enough blood, then use a cotton swab or a bandage to halt any bleeding.

It only takes a few minutes to complete the process. Many people would feel dizzy or sick when they see blood, and moderate bruising around the draw site may occur for a few days afterward.

A lab technician will dye the sample to emphasize the eosinophils and other blood cells, then count the number of eosinophils and other blood cells available under a microscope to determine the outcome.

Normal Results

An eosinophil count of fewer than 500 cells per microliter (cells/mcL) is considered normal.

The normal value ranges may vary slightly between laboratories. Discuss the significance of your specific test results with your healthcare professional.

The measurements for the outcomes of these tests are shown in the example above. Some laboratories may test different specimens or use different metrics.

Abnormal results

If you have more than 500 eosinophil cells per microliter of blood, you have a condition called eosinophilia. Eosinophilia can be mild (500–1,500 eosinophil cells per microliter), moderate (1,500–5,000 eosinophil cells per microliter), or severe (5,000 eosinophil cells per microliter) (greater than 5,000 eosinophil cells per microliter). This could be related to one or more of the following factors:

  • a parasitic worm infection 
  • an autoimmune disease 
  • severe allergic reactions
  • eczema
  • asthma
  • allergies caused by the seasons
  • Some types of cancers such as leukaemia and others
  • colitis ulcerative
  • scarlet fever is a contagious disease that affects
  • lupus
  • Crohn’s disease is a chronic inflammatory bowel illness that affects
  • a serious medication reaction
  • Rejection of an organ transplant

An excessively low eosinophil count can be caused by alcohol consumption or high cortisol production, as in Cushing’s disease. Cortisol is a hormone that the body produces naturally. It’s also possible that low eosinophil counts are linked to the time of day. Eosinophil numbers are lowest in the morning and greatest in the evening in normal circumstances.

Low numbers of eosinophils are usually not a cause for concern until other white cell counts are abnormally low, as in the case of alcohol misuse or Cushing’s illness. If the total number of white blood cells is low, it could indicate an issue with the bone marrow.

Complications associated with an eosinophil count?

A routine blood draw is used for an eosinophil count, which you have probably had many times before.

There is a small chance of slight bruising at the needle site, as with every blood test. After blood is extracted, the vein may swell in rare situations. Phlebitis is the medical term for this condition. This ailment can be treated by applying a warm compress many times per day. If this doesn’t work, you should see your doctor.

If you have a bleeding disorder or take blood-thinning medications like warfarin (Coumadin) or aspirin, you may experience excessive bleeding. This necessitates rapid medical assistance.

What happens after an eosinophil count?

Your doctor will recommend a short-term medication to ease symptoms and return your white blood cell count to normal if you have an allergy or parasite infection.

If your eosinophil count shows that you have an autoimmune disease, your doctor may order additional testing to figure out specific diseases you have. Elevated concentrations of eosinophils can be caused by a variety of medical conditions, so it’s crucial to work with your physician to figure out what’s causing them.

Eosinophilia and cancer

Irritable bowel disease (IBD) and other gastrointestinal diseases are linked to an increased risk of colorectal cancer in those with eosinophilia. In chronic gastritis, eosinophils and mast cells may play a dual function in either preventing or encouraging the development of gastric cancer. Studies by Pretlow, et al. [8] were the first to link eosinophils to colorectal cancer pathogenesis. Eosinophilia is seen in tumors that arise from epithelial cells, such as the breast, lung, cervix, and ovary, as well as gastrointestinal cancers. Hematologic cancers including Hodgkin’s and non-lymphoma, Hodgkin’s as well as some leukemias, are linked to eosinophilia. Eosinophilia appears to be caused by tumor cells secreting IL-3 and IL-5. The occurrence or lack of eosinophilia is linked to a good or worse prognosis; however, the mechanism of action is unknown.

Eosinophils are found in the tissues around colorectal cancers and nasopharyngeal cancers. Eosinophilia and the existence of peritumoral eosinophils are linked to a better prognosis in colorectal cancer. Similarly, a rise in serum eosinophil counts following prostate cancer treatment has been linked to a longer survival time.

Tumor-associated blood eosinophilia (TABE) is a type of eosinophilia that develops after a tumor has progressed and is associated with a bad prognosis. TABE is typically seen in kidney cancer, thyroid cancer, liver cancer, gallbladder cancer, pancreatic cancer, and breast cancer.