Introduction:
Eosinophils are part of white blood cells that protect the body from parasitic infections and increase in response to allergens. On average, eosinophils take about 5 % to 7 % of the white blood cells or about 100 to 500 eosinophils per microliter of blood. In certain conditions, such as allergies, the eosinophils multiply to cause a disease called eosinophilia.
Hypereosinophilic syndrome (HES) is categorized as a group of rare diseases characterized by persistent overproduction of eosinophils, infiltration of eosinophils, and the release of mediators that damage multiple organs. The urgency of treatment and the choice of treatment depends not only on the patient's symptoms but also on laboratory findings and mutation analysis results.
What Is Hypereosinophilic Syndrome?
Hypereosinophilic syndrome (HES) is a rare condition that happens when eosinophilia accelerates, speeding up eosinophil production and increasing the number of eosinophils. This eosinophil overload can damage the organs, including the heart, lungs, skin, and nervous system. If left untreated, the hypereosinophilic syndrome can be life-threatening. Most HES patients are over 20 years of age, but children can also be affected. Most variants of HES are considered benign (non-cancerous), but a subset is known to be myeloproliferative neoplasms, which can turn into cancer.
What Causes Hypereosinophilic Syndrome?
Some types of eosinophilia syndrome tend to occur in the family. Other types are associated with a particular type of cancer, infection, or other health problem.
Researchers do not know all the factors that cause the dramatic increase in eosinophils that causes most cases of eosinophilia syndrome. However, we have identified some conditions or situations that may be the cause.
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Myeloproliferative Disorders - These disorders are characterized by the overproduction of blood cells in the bone marrow.
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High Levels of Interleukin-5 - This protein is produced by white blood cells.
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Genetic Abnormality - Promotes cell proliferation.
What Are the Types of Hypereosinophilic Syndrome?
Hypereosinophilic syndrome can be divided into three major categories: primary (or neoplastic), secondary (or reactive), and idiopathic. Idiopathic HES is a diagnosis and treatment of exclusion that no other cause of eosinophilia can be found. In primary HES, genetic mutation triggers the bone marrow to stimulate eosinophil production. In secondary HES, underlying diseases produce proteins (called cytokines) that stimulate eosinophils.
What Are the Signs and Symptoms Associated With Hypereosinophilic Syndrome?
Common and early HES symptoms include fatigue, cough, shortness of breath, myalgia, skin rash, and fever. Symptoms of hypereosinophilia correlate with areas of the body affected by high levels of eosinophils. Such as congestive heart failure, cardiomyopathy, myocarditis, and pericardial effusion. The accumulation of eosinophils in the lungs can cause recurrent upper respiratory tract infections, coughing, and dyspnea.
Symptoms of HES are based on the affected area and include:
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Skin - Eczema, thickening of the skin, hives.
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Lungs - Cough, shortness of breath, wheezing.
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Heart - Chest pain, difficulty breathing.
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Neurologic Disease - Central nervous system dysfunction and peripheral nephropathy.
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Thrombosis - Formation of blood clots.
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Eyes - Impaired vision.
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Gastrointestinal Tract - Loss of appetite and weight, pain, vomiting, diarrhea.
How Is Hypereosinophilic Syndrome Diagnosed?
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Health care providers use a removal process to diagnose HES; if a persistent itchy rash occurs, the healthcare provider may look for specific skin conditions and perform tests to prescribe treatments. In addition, if symptoms persist, doctors may test the blood for high levels of eosinophils.
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If the symptoms indicate a liver problem and the doctor has ruled out other causes, they can have a liver function blood test. They may also perform a biopsy to confirm the diagnosis of hypereosinophilic syndrome.
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If the symptoms indicate a liver problem and the doctor has ruled out other causes, the patient can have a liver function blood test. They may also perform a biopsy to confirm the diagnosis of hypereosinophilic syndrome.
How Is Hypereosinophilic Syndrome Treated?
Health care providers focus on reducing high levels of eosinophils in blood and tissues. Standard treatments include corticosteroids and chemotherapeutic agents.
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Steroids - Prednisone and Methylprednisolone are prescribed.
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Imatinib - It is an oral drug used to treat cancer.
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Hydroxyurea - Hydroxyurea is an oral chemotherapeutic drug. It usually takes up to two weeks for a response to this drug to be seen.
What Can One Expect if They Have Hypereosinophilic Syndrome?
The prognosis or expected outcome depends on the particular situation. For example, if the condition is associated with a specific cause, such as bone marrow disorders. If the condition affects the bone marrow, the healthcare provider may use treatments that target the bone marrow disease.
However, if the healthcare provider cannot determine the cause of HES, treatment will focus on the symptoms. Such as, if HES targets the lungs, the upper respiratory tract infection is more likely to recur, and treatment is focused on treating the condition.
The earlier HES is diagnosed and treated; the less likely a permanent problem will occur.
Conclusion:
Hypereosinophilic syndrome (HES) is a rare group of disorders characterized by persistent eosinophilia with evidence of organ involvement. Signs and symptoms vary greatly depending on which part of the body is affected. Any organ can be affected by HES, but the heart, central nervous system, skin, and airways are most commonly affected. This condition was initially thought to be idiopathic or of unknown cause. However, recent advances in diagnostic testing have made it possible to identify the cause in about a quarter of cases.
