High eosinophils on blood test results, what do they mean?

The results of your blood test can reveal a variety of health conditions that may be worrying. A complete blood count accompanied by a differential blood test will show the number of each type of white blood cell in your blood, eosinophils one of them. If eosinophils are high, you have a condition known as eosinophilia. So, what causes high eosinophil levels? How do you reduce high eosinophils?

What are high eosinophils (eosinophilia)?

Eosinophilia is a condition when eosinophils in the blood are higher than normal. This type of white blood cell is normally less than 500 cells per microliter of blood.

You are considered to have eosinophilia if your eosinophil count is more than 500 per microliter of blood. Meanwhile, the number of eosinophils more than 1,500 per microliter is called hypereosinophilia.

In more detail, eosinophilia can be divided into three levels, namely:

• Mild: as many as 500-150 eosinophils per microliter
• Medium: as many as 1,500-5,000 eosinophils per microliter
• Weight: more than 5,000 per microliter

Eosinophils are a type of white blood cell that fight disease. Quoted from the Mayo Clinic, the functions of this type of white blood cell are:

• Destroys foreign substances
• Regulates inflammation
• An allergic reaction

High eosinophils are one of the most common signs of parasitic infection, allergic reactions, or cancer. Eosinophilia can occur in the blood (blood eosinophilia) or in the tissue of infection or inflammation (tissue eosinophilia).

Tissue eosinophilia can be detected through an exploratory procedure or when fluids in your body, such as mucus from nasal tissue, are examined in a laboratory. If you have tissue eosinophilia, the eosinophil level in the bloodstream may be within normal limits.

Meanwhile, blood eosinophilia can be detected by a blood test, usually as part of a complete blood count.

Causes of high eosinophils

Eosinophilia occurs when the bone marrow produces too many eosinophils. Quoted from a journal published in the US National Library of Medicine, several conditions that cause your eosinophils to increase, include:

1. Allergies

Mild eosinophilia, which is when the eosinophil count is lower than 1,500 / mcL but higher than normal, is often found in people with allergic diseases, such as allergic rhinitis and asthma. Meanwhile, atopic dermatitis can result in a slightly higher number of eosinophils.

Chronic sinusitis, especially the polypoid type, can cause eosinophilia in the mild to moderate category. When you experience this condition, you will usually experience nasal allergies and asthma first.

Drug allergies can also cause mild to severe eosinophilia. Medicines that can cause this condition are:

• Antibiotics: Penicillins, cephalosporins, dapsone, sulfa-based antibiotics
• Xanthine oxidase inhibitors: Allopurinol
• Antiepileptic: Carbamazepine, phenytoin, lamotrigine, valproic acid
• Antiretrovirals: Nevirapine, efavirenz
• Nonsteroidal anti-inflammatory drug: Ibuprofen

2. Infection

A number of parasitic infections can raise your eosinophils. These infections can cause you to experience mild to severe high eosinophils. Some of them are:

• Worm infection:
  • Ascariasis
  • Hookworm infection
  • Trichinellosis
  • Cysticercosis
  • Echinococcosis
  • Strongyloidiasis
  • Tropical pulmonary eosinophilia
  • Loiasis
  • Schistosomiasis
  • Clonorkiasis
• Protoza infection, such as Isospora belli, Dientamoeba fragilis, sarcocystis

3. Autoimmune disease

Various autoimmune diseases can also make your eosinophils high. Eosinophilia associated with autoimmune diseases are:

• Dermatomyositis
• Rheumatoid arthritis is severe
• Progressive systemic sclerosis
• Sjögren's Syndrome
• Systemic lupus erythematosus
• Behcet's Syndrome
• Inflammatory bowel disease
• Sarcoidosis
• Bullous pemphigoid
• Dermatitis herpetiformis (Celiac disease)

4. Cancer

A high eosinophil count can also be a sign of malignancy, aka cancer. Even so, that does not mean you will definitely get cancer if you have eosinophilia.

Some cancers that have been linked to eosinophilia include:

• Acute or chronic eosinophilic leukemia
• Lymphoma (T and Hodgkin cells)
• Chronic myelomonocytic leukemia
• Lung cancer
• Thyroid cancer
• Adenocarcinoma (glandular cancer) of the digestive tract
• Squamous epithelial related cancer (cervix, vagina, penis, skin, nasopharynx, bladder)

The Cleveland Clinic website calls eosinophilic disorders often referred to by names that describe where the disorder occurs. For example:

• Eosinophilic cystitis, which is an abnormality in the bladder
• Eosinophilic fasciitis, which is a disorder of the fascia, or connective tissue throughout the body
• Eosinophilic pneumonia, which is a disorder of the lungs
• Eosinophilic colitis, which is an abnormality in the large intestine (large intestine)
• Eosinophilic esophagitis, which is a disorder of the esophagus
• Eosinophilic gastritis, which is a stomach disorder
• Eosinophilic gastroenteritis, which is a disorder of the stomach and small intestine

What is the danger of high eosinophils?

Very high levels of eosinophils can lead to a condition known as hypereosinophilic syndrome. This condition falls into the category of moderate to severe eosinophilia, and can cause several conditions that you need to be aware of.

Some of these conditions can be divided into:

• Idiopathic hypereosinophilic syndrome: eosinophils greater than 1,500 / mcL of blood with end-stage organ damage.
• Lymphoproliferative hypereosinophilic syndrome: eosinophils greater than 1,500 / mcL of blood, often associated with a rash.
• Myeloproliferative hypereosinophilic syndrome: eosinophils greater than 1,500 / mcL of blood, the symptoms that appear frequently include splenomegaly, heart-related complications, and thrombosis.
• Episodic eosinophilia associated with angioedema (G syndrome): presenting conditions may include cyclic fever, swelling, hives, pruritus, a significant increase in eosinophils, and an increase in IgM (a form of antibody that appears to fight infection).

How to reduce high eosinophils?

How to reduce high eosinophils varies depending on the cause. Some medications that may be given to treat eosinophilia include:

• Stopping certain medications, especially in case of an allergic drug reaction
• Avoiding certain foods, especially in cases of esophagitis
• Take anti-infective or anti-inflammatory medication

You may not notice your eosinophils are above normal levels if you don't have a blood test. To find the exact cause of your increased eosinophils, your doctor may do some additional investigations and other additions to confirm the disease more clearly.