From the Guidelines
Elevated eosinophils, or eosinophilia, requires immediate medical attention to determine the underlying cause and prevent potential organ damage. Eosinophilia occurs when your blood contains more than 500 eosinophils (a type of white blood cell) per microliter. Common causes include:
- Allergic reactions
- Parasitic infections
- Certain medications
- Autoimmune disorders
- Some cancers Your doctor will likely order additional tests such as:
- Complete blood count with differential
- Stool examination for parasites
- Allergy testing
- Chest imaging depending on your symptoms and medical history. Treatment directly addresses the underlying cause rather than the eosinophilia itself. For allergic conditions, antihistamines like cetirizine (10mg daily) or corticosteroids may be prescribed 1. Parasitic infections typically require specific antiparasitic medications such as albendazole (400mg twice daily for 3-5 days) or ivermectin (200mcg/kg as a single dose) 1. In cases of drug-induced eosinophilia, discontinuing the offending medication often resolves the condition. For more severe cases related to hypereosinophilic syndromes, medications like prednisone (starting at 1mg/kg/day) or specialized treatments such as mepolizumab may be necessary 1. Eosinophils play an important role in your immune system's response to parasites and allergic reactions, but when elevated without appropriate cause, they can damage tissues and organs through the release of inflammatory substances. It is essential to consult with a healthcare provider for proper evaluation and treatment to prevent long-term complications. The most recent guidelines recommend a comprehensive approach to diagnosis and management, including consideration of hereditary, primary, and secondary causes of hypereosinophilia 1. In the case of evolving life-threatening end-organ damage, immediate diagnosis and treatment are crucial to avoid delay in therapy 1. Overall, elevated eosinophils require prompt medical attention to determine the underlying cause and provide appropriate treatment to prevent potential complications.
From the Research
Definition and Classification of Eosinophilia
- Eosinophilia is defined as an elevation of eosinophils in the bloodstream, with a count of > 500 cells/μL 2, 3.
- It can be classified into mild (500-1500 cells/μl), moderate (1500-5000 cells/μl), and severe for an eosinophil count > 5000 cells/μl 2.
- The term "hypereosinophilia" defines a condition characterized by a blood eosinophil count > 1500 cells/μl in at least two consecutive tests made with a minimum of a 4-week interval 2.
Causes of Eosinophilia
- The causes of eosinophilia are various and can be summarized by the acronym "APLV", which refers to Allergic disorders, Parasitic infections, Leukemia/Lymphomas (and solid tumors), and Vasculitis-Immunodeficiency diseases 2.
- Allergic disorders and parasitic infections are the most commonly identified causes of eosinophilia 2.
- Eosinophilia can also be associated with autoimmune, connective tissue disease, rheumatologic disease, primary eosinophilia, and malignant states 3.
Clinical Manifestations and Organ Involvement
- Eosinophilia can be associated with a wide range of clinical manifestations, from benign asymptomatic presentations to life-threatening complications 4.
- Eosinophils may be directly responsible for organ damage, mainly at the cardiac, pulmonary, and cutaneous levels, deriving from the release of granule products, lipidic mediators, and cytokines 2.
- The prognosis and choice of treatment depend on the degree of eosinophilia, severity of organ involvement, and etiology of the eosinophilia 4.
Treatment and Management
- Treatment of eosinophilia depends on the underlying cause and severity of the condition 5, 4.
- Systemic glucocorticoids are commonly used to manage eosinophil-related diseases, but novel biologic therapies targeting the interleukin-5 pathway can help reduce their use and minimize adverse effects 6.
- A practical approach to diagnosis and treatment involves considering the patient's history, clinical manifestations, and level and persistence of blood eosinophilia 2, 4.