Home Biomarkers Abs. Eosinophil Count

Abs. Eosinophil Count

CBC Biomarker

Sample Needed

Collection Type: Blood

Body System

Related System: CBC

Overview

Absolute eosinophil count measures the number of eosinophils a type of white blood cell involved in immune responses to parasites, allergic reactions and certain inflammatory processes per unit of blood. It is calculated from the complete blood count (CBC) with differential and reflects the true eosinophil burden rather than a percentage. Elevated counts (eosinophilia) can suggest allergic conditions (asthma, allergic rhinitis, atopic dermatitis), parasitic infections, drug reactions, autoimmune or hematologic disorders and rare hypereosinophilic syndromes; low counts (eosinopenia) commonly occur with acute infection, stress or corticosteroid use. Normal values vary modestly with age and pregnancy and show diurnal variation (often higher at night); gender differences are minimal.

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Test Preparation

No special preparation is required

Why Do I Need This Test

Profile: included in CBC with differential - Symptoms: unexplained rashes, persistent cough/wheezing, recurrent infections, gastrointestinal symptoms, fever, or signs of organ dysfunction - Diagnoses/monitoring: allergies/asthma, parasitic infections, drug reactions, hematologic disorders, hypereosinophilic syndrome - Reasons for abnormal levels: allergies, parasites, medications, infections, autoimmune or neoplastic disease, corticosteroids or stress - Biological meaning: high values indicate eosinophil-driven inflammation; low values suggest suppression or redistribution - Behaviors/family history: travel to endemic areas, pet/exposure history, atopy or family history of asthma/allergies

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Understanding Test Results

Low (eosinopenia): <0.05 ×10^9/L (<50 cells/µL) may be seen in acute bacterial infections, physiologic stress, Cushing’s syndrome or after corticosteroid therapy; usually not dangerous alone but reflects immune suppression or stress response.
Normal: 0.0–0.5 ×10^9/L (0–500 cells/µL) expected baseline for healthy individuals.
Mild eosinophilia: 0.5–1.5 ×10^9/L (500–1,500 cells/µL) commonly due to allergic disease, mild parasitic infection or drug reaction.
Moderate eosinophilia: 1.5–5.0 ×10^9/L (1,500–5,000 cells/µL) suggests more significant parasitic infestation, systemic allergic/autoimmune conditions, or certain hematologic disorders.
Severe eosinophilia: >5.0 ×10^9/L (>5,000 cells/µL) raises concern for hypereosinophilic syndrome or organ‑damaging eosinophilic disease and warrants urgent further evaluation (cardiac, pulmonary, neurologic assessment and specialist referral).
Interpretation requires correlation with symptoms, medication history, travel/exposure risk and other lab/imaging studies.

Normal Range

0.0-0.5 ×10^9/L OR 0-500 cells/µL

FAQs

Q: What does high abs eosinophils mean?

A: High absolute eosinophils (eosinophilia) mean an elevated eosinophil white‑blood‑cell count, often linked to allergies (asthma, eczema), parasitic infections, drug reactions, autoimmune conditions, certain cancers, or primary eosinophilic disorders. Severity guides evaluation; clinicians will check recent allergies, travel, medications and infections, and may order repeat blood counts, stool tests, imaging or specialist referral to determine cause and treatment.

Q: What if abs eosinophils are low?

A: Low absolute eosinophils (eosinopenia) are often transient and benign seen with acute infections, stress, or corticosteroid/Cushing’s effects. They rarely indicate bone marrow failure unless persistent and accompanied by other cytopenias. Management: correlate with symptoms, review medications (especially steroids), repeat the blood count, and investigate for infection or endocrine causes if low counts persist or other blood lines are abnormal.

Q: What is a normal eosinophil count in pregnancy?

A: A normal absolute eosinophil count in pregnancy is generally similar to non‑pregnant adults: about 0.0–0.5 ×10^9/L (0–500 cells/µL). Pregnancy may cause mild reductions in eosinophils, so slightly lower values are common. Persistently elevated counts above this range may suggest allergy, parasitic infection, drug reaction, or other conditions and should prompt clinical review.

Q: What kind of infection causes high eosinophils?

A: High eosinophil counts are most commonly caused by parasitic infections, especially tissue‑invading helminths such as roundworms, hookworms, schistosomes and strongyloides. Eosinophilia can also occur with certain fungal or protozoal infections, allergic conditions (asthma, allergic rhinitis) and drug reactions. When unexplained, clinicians check travel history, exposures and perform stool, blood and serologic tests to find parasites.

Q: How to reduce abs eosinophil count?

A: Reduce an elevated absolute eosinophil count by treating the underlying cause: diagnose and treat parasitic infections, control allergic triggers, and stop offending drugs. Short courses of systemic corticosteroids or targeted inhaled steroids often lower counts. For persistent or severe eosinophilia, immunomodulatory biologics (e.g., anti–IL‑5 agents) or other immunosuppressants may be used under specialist care. Follow-up blood tests and clinician review are essential.

Q: What is the danger range for eosinophils?

A: Normal eosinophil counts are about 0–500 cells/µL (roughly 1–6% of white cells). Counts above 500 indicate eosinophilia; values over 1,500 cells/µL are concerning for potential organ damage and warrant evaluation. Counts above 5,000 cells/µL are considered severe and carry a high risk of complications. Clinical correlation and prompt medical assessment are recommended.