Chronic Eosinophilic Leukemia: Symptoms, Diagnosis and Treatment

We'll take a look at chronic eosinophilic leukemia, along with its symptoms and treatment.
Chronic Eosinophilic Leukemia: Symptoms, Diagnosis and Treatment
María Irene Benavides Guillém

Written and verified by the doctor María Irene Benavides Guillém.

Last update: 07 February, 2023

Chronic eosinophilic leukemia is a neoplastic disease in which eosinophils multiply excessively, affecting several organs. It can even lead to death.

It is characterized by the persistent presence of a high number of eosinophils in the blood, which is called “hypereosinophilia”.

Its early diagnosis is essential in order to start treatment promptly and to have more chances of success. That is why we’re going to tell you how this disease is confirmed and its symptoms.

What are eosinophils?

We must begin by understanding what eosinophils are. They are a type of leukocyte or white blood cells.

They are so named because they contain granules that stain intensely with an acidic pigment called eosin. Under the microscope, when staining is used, these cells appear pink-orange in color.

They play an important role in the human body as they’re an active part of the immune system.

Their best-known function is the ability to destroy parasites with the substances in their granules. But they’re also involved in the defense against viruses, fungi and bacteria.

Eosinophils are also involved in the response to tumors and in metabolism. They also contribute to the repair and remodeling of tissues and therefore play a role in the regeneration of skin, muscles, and liver.

However, they can also have a negative effect. The consequence of their hyperactivity or excessive action is damage to certain organs and certain unpleasant symptoms.

This is the case, for example, in allergic asthma. These cells are among the main cells responsible for prolonged inflammation.

Eosinophils in the blood.
Eosinophils circulate in the blood and contain granules containing substances that mediate the allergic response.

Why can eosinophils increase?

Before making a diagnosis of chronic eosinophilic leukemia, all other causes of hypereosinophilia must be ruled out.

From the functions of eosinophils, one can deduce what can cause them to increase. They will expand in reaction to parasitic infections, and allergic and autoimmune diseases, as well as in response to the ingestion of some drugs.

Therefore, if the physician detects a blood test with many eosinophils, he will ask us what diseases we have suffered from before, what medications we have taken, or if we have been exposed to situations in which we could have been infected with parasites.

Eosinophilia can also be one of the manifestations of malignant tumors in different tissues in the:

How is chronic eosinophilic leukemia diagnosed?

The World Health Organization (WHO) establishes that, after rigorously excluding the presence of reactive or secondary eosinophilia, specialized diagnostic tests, such as a bone marrow biopsy, should be performed.

Molecular and genetic studies will detect changes that explain the disordered cell proliferation. In this way, it will be determined whether there’s an intrinsic defect or primary hypereosinophilia.

The WHO warns that criteria such as duration of symptoms, number of eosinophils, or organ involvement are usually arbitrary or delayed. That is, their presence or absence doesn’t rule out the disease.

Worse still, they can be considered very late in the evolution of leukemia. Let us remember that early diagnosis is vital in order to avoid complications.

What are the symptoms of chronic eosinophilic leukemia?

It should be noted that chronic eosinophilic leukemia is more common in males and in the sixth decade of life. In these groups, it’s suspected first.

As for symptoms, the Mayo Clinic recently published the characteristics of a group of patients with chronic eosinophilic leukemia. More than half had fatigue.

Second in frequency were gastrointestinal complaints, such as diarrhea, abdominal pain, nausea and vomiting. Smaller proportions were weight loss, coughing and night sweats.

People with chronic eosinophilic leukemia often have anemia and low platelet counts. So they may have symptoms secondary to these disorders. For example, they often suffer repeated bacterial and viral infections, which are difficult to recover from.

In addition, organs such as the heart and lungs can be affected, leading to a life-threatening medical emergency. Similarly, the spleen and lymph nodes may be enlarged.

Skin lesions are common, including dermatitis and urticaria.
Fatiga por leucemia eosinofílica crónica.
Fatigue is a nonspecific symptom, but its persistence should prompt a diagnostic search.

Treatment of chronic eosinophilic leukemia

Chronic eosinophilic leukemia is a serious disease. If left untreated, eosinophils can invade various organs in the body and damage them. Heart and lungs are usually the most affected, although any tissue can be affected over weeks and months.

Similarly, the disease can develop into acute leukemia. In such cases, the condition becomes aggressive and the internal production of leukocytes, red blood cells, and platelets is drastically reduced.

The goal of treatment is always to decrease the number of circulating eosinophils. This is done to prevent tissue invasion and organ damage.

The first line of initiation, followed by clinical guidelines, is corticosteroids. These anti-inflammatory agents are combined with hydroxycarbamide, interferon alpha, or imatinib.

Some patients will receive a bone marrow transplant. This isn’t a recommended therapy for all cases. Because several patients are elderly, favorable results can’t be expected when using hematopoietic stem cells. However, alternatives continue to be investigated.

However, since many people don’t improve with chemotherapy and immunotherapy, possibilities are being explored with genetics. The results are promising, but these approaches aren’t available for all diagnosed patients.

In any case, the essential thing is to be attentive to the body’s signals. See your doctor immediately if you have any of the symptoms mentioned above.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.


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This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.