Eosinophils
Eosinophils
Eosinophils are white blood cells involved in the response to allergens, infections, and inflammation.
Eosinophils are white blood cells involved in the response to allergens, infections, and inflammation.
Eosinophils
Normal range
Normal range
0.04-0.4 x10⁹/L
0.04-0.4 x10⁹/L
Normal range
0.04-0.4 x10⁹/L
0.04-0.4 x10⁹/L
Normal range
Eosinophils
Eosinophils
Eosinophils are white blood cells involved in the response to allergens, infections, and inflammation.
Eosinophils
Normal range
0.04-0.4 x10⁹/L
Normal range
0.04-0.4 x10⁹/L
0.04-0.4 x10⁹/L
Normal range
Eosinophils
Eosinophils
Eosinophils are white blood cells involved in the response to allergens, infections, and inflammation.
Eosinophils
Normal range
0.04-0.4 x10⁹/L
Normal range
0.04-0.4 x10⁹/L
0.04-0.4 x10⁹/L
Normal range
Eosinophils
Dr. Yiannis Balanos
MBBS MRCGP
Your Allergy Detectives
Your Allergy Detectives
Every immune response in your body relies on specialised cells called eosinophils. When these levels are abnormal, your body's ability to detect and respond to allergens, parasites, and certain infections can be significantly affected.
Eosinophils are white blood cells that play a crucial role in your immune system's response to allergic reactions, parasitic infections, and certain inflammatory conditions. Think of them as your body's specialist detectives—when eosinophil levels are outside the normal range, it often indicates your immune system is reacting to perceived threats.
Every immune response in your body relies on specialised cells called eosinophils. When these levels are abnormal, your body's ability to detect and respond to allergens, parasites, and certain infections can be significantly affected.
Eosinophils are white blood cells that play a crucial role in your immune system's response to allergic reactions, parasitic infections, and certain inflammatory conditions. Think of them as your body's specialist detectives—when eosinophil levels are outside the normal range, it often indicates your immune system is reacting to perceived threats.
What can reduce your Eosinophil Levels?
What can reduce your Eosinophil Levels?
What can reduce your Eosinophil Levels?
While not particularly common, learn what can lower your counts.
Read more
Why your allergies are acting up
Why your allergies are acting up
Why your allergies are acting up
From seasonal allergies to external exposures, learn the factors that can affect your body's immune response.
Read more
When to Investigate Further
When to Investigate Further
When to Investigate Further
Understanding which symptoms and patterns warrant medical evaluation and the conditions that may be revealed.
Read more
Understanding Your Results
Understanding Your Results
Understanding Your Results
Decode your blood test numbers and know exactly what your eosinophil levels mean for your health.
Read more
What can reduce your Eosinophil Levels?
Low Eosinophils (Eosinopenia): Low eosinophil counts are relatively uncommon and typically occur when your body is under significant stress or fighting infections. During these times, your immune system prioritises producing other types of white blood cells, temporarily reducing eosinophil production.
Low eosinophil counts themselves do not cause symptoms. Eosinopenia is generally a marker of underlying conditions rather than a problem requiring direct treatment.
What can reduce your Eosinophil Levels?
Low Eosinophils (Eosinopenia): Low eosinophil counts are relatively uncommon and typically occur when your body is under significant stress or fighting infections. During these times, your immune system prioritises producing other types of white blood cells, temporarily reducing eosinophil production.
Low eosinophil counts themselves do not cause symptoms. Eosinopenia is generally a marker of underlying conditions rather than a problem requiring direct treatment.
What can reduce your Eosinophil Levels?
Low Eosinophils (Eosinopenia): Low eosinophil counts are relatively uncommon and typically occur when your body is under significant stress or fighting infections. During these times, your immune system prioritises producing other types of white blood cells, temporarily reducing eosinophil production.
Low eosinophil counts themselves do not cause symptoms. Eosinopenia is generally a marker of underlying conditions rather than a problem requiring direct treatment.
Why your allergies are acting up
High Eosinophils (Eosinophilia): High eosinophil counts indicate your immune system is actively responding to allergens, infections, or other substances it perceives as threats. However, elevated eosinophil counts themselves typically do not cause symptoms—rather, you experience symptoms from the underlying conditions that are driving the elevated count.
The symptoms you might notice—such as persistent cough, wheezing, skin rashes, itching, nasal congestion, or digestive problems—are caused by the allergic responses (such as hayfever or asthma), parasitic infections in rare cases, or inflammatory processes that have triggered the eosinophil response.
In rare cases of extremely high eosinophil counts, the eosinophils can cause issues in the organs of the body. However, this occurs only with persistently very high counts (typically >1.5 × 10⁹/L) and represents a distinct medical condition requiring specialist care.
Why your allergies are acting up
High Eosinophils (Eosinophilia): High eosinophil counts indicate your immune system is actively responding to allergens, infections, or other substances it perceives as threats. However, elevated eosinophil counts themselves typically do not cause symptoms—rather, you experience symptoms from the underlying conditions that are driving the elevated count.
The symptoms you might notice—such as persistent cough, wheezing, skin rashes, itching, nasal congestion, or digestive problems—are caused by the allergic responses (such as hayfever or asthma), parasitic infections in rare cases, or inflammatory processes that have triggered the eosinophil response.
In rare cases of extremely high eosinophil counts, the eosinophils can cause issues in the organs of the body. However, this occurs only with persistently very high counts (typically >1.5 × 10⁹/L) and represents a distinct medical condition requiring specialist care.
Why your allergies are acting up
High Eosinophils (Eosinophilia): High eosinophil counts indicate your immune system is actively responding to allergens, infections, or other substances it perceives as threats. However, elevated eosinophil counts themselves typically do not cause symptoms—rather, you experience symptoms from the underlying conditions that are driving the elevated count.
The symptoms you might notice—such as persistent cough, wheezing, skin rashes, itching, nasal congestion, or digestive problems—are caused by the allergic responses (such as hayfever or asthma), parasitic infections in rare cases, or inflammatory processes that have triggered the eosinophil response.
In rare cases of extremely high eosinophil counts, the eosinophils can cause issues in the organs of the body. However, this occurs only with persistently very high counts (typically >1.5 × 10⁹/L) and represents a distinct medical condition requiring specialist care.
When to Investigate Further
Eosinophil counts are not managed directly - they are investigated as markers of underlying conditions. The clinical significance lies in what abnormal counts might indicate about your health.
Slight elevation is usually expected in allergic conditions, and is commonly associated with asthma. Levels above 1.5 × 10⁹/L or persistently rising levels would warrant further medical investigation into an underlying cause.
The focus is always on identifying and treating the underlying condition causing the abnormal count.
When to Investigate Further
Eosinophil counts are not managed directly - they are investigated as markers of underlying conditions. The clinical significance lies in what abnormal counts might indicate about your health.
Slight elevation is usually expected in allergic conditions, and is commonly associated with asthma. Levels above 1.5 × 10⁹/L or persistently rising levels would warrant further medical investigation into an underlying cause.
The focus is always on identifying and treating the underlying condition causing the abnormal count.
When to Investigate Further
Eosinophil counts are not managed directly - they are investigated as markers of underlying conditions. The clinical significance lies in what abnormal counts might indicate about your health.
Slight elevation is usually expected in allergic conditions, and is commonly associated with asthma. Levels above 1.5 × 10⁹/L or persistently rising levels would warrant further medical investigation into an underlying cause.
The focus is always on identifying and treating the underlying condition causing the abnormal count.
Understanding Your Results
Eosinophil count is measured through a full blood count (FBC).
Normal range: 0.04-0.4 × 10⁹/L
Low eosinophils (Eosinopenia): < 0.04 × 10⁹/L
High eosinophils (Eosinophilia): > 0.4 × 10⁹/L
The FBC test provides the total count of all white blood cells, helping identify the significance of any abnormality. Additional tests may be recommended to determine the underlying cause, including specific allergy testing.
Understanding Your Results
Eosinophil count is measured through a full blood count (FBC).
Normal range: 0.04-0.4 × 10⁹/L
Low eosinophils (Eosinopenia): < 0.04 × 10⁹/L
High eosinophils (Eosinophilia): > 0.4 × 10⁹/L
The FBC test provides the total count of all white blood cells, helping identify the significance of any abnormality. Additional tests may be recommended to determine the underlying cause, including specific allergy testing.
Understanding Your Results
Eosinophil count is measured through a full blood count (FBC).
Normal range: 0.04-0.4 × 10⁹/L
Low eosinophils (Eosinopenia): < 0.04 × 10⁹/L
High eosinophils (Eosinophilia): > 0.4 × 10⁹/L
The FBC test provides the total count of all white blood cells, helping identify the significance of any abnormality. Additional tests may be recommended to determine the underlying cause, including specific allergy testing.
The Takeaway
Eosinophil levels provide important information about your immune system's response to allergens, parasites, and certain infections. Abnormal levels are typically markers of underlying conditions rather than direct causes of symptoms. Most conditions associated with abnormal eosinophil counts are manageable once properly identified and treated.
High counts often indicate allergic conditions that can significantly impact quality of life if left untreated. Low counts, while less clinically significant, may indicate underlying infections or medication effects that warrant medical review.
If you're experiencing persistent allergic symptoms or have unexplained skin issues, this could be your body's way of signalling an immune reaction. A simple blood test can reveal your eosinophil levels and guide appropriate investigation and treatment if needed.
The Takeaway
Eosinophil levels provide important information about your immune system's response to allergens, parasites, and certain infections. Abnormal levels are typically markers of underlying conditions rather than direct causes of symptoms. Most conditions associated with abnormal eosinophil counts are manageable once properly identified and treated.
High counts often indicate allergic conditions that can significantly impact quality of life if left untreated. Low counts, while less clinically significant, may indicate underlying infections or medication effects that warrant medical review.
If you're experiencing persistent allergic symptoms or have unexplained skin issues, this could be your body's way of signalling an immune reaction. A simple blood test can reveal your eosinophil levels and guide appropriate investigation and treatment if needed.
The Takeaway
Eosinophil levels provide important information about your immune system's response to allergens, parasites, and certain infections. Abnormal levels are typically markers of underlying conditions rather than direct causes of symptoms. Most conditions associated with abnormal eosinophil counts are manageable once properly identified and treated.
High counts often indicate allergic conditions that can significantly impact quality of life if left untreated. Low counts, while less clinically significant, may indicate underlying infections or medication effects that warrant medical review.
If you're experiencing persistent allergic symptoms or have unexplained skin issues, this could be your body's way of signalling an immune reaction. A simple blood test can reveal your eosinophil levels and guide appropriate investigation and treatment if needed.
References
Gleich, G.J., & Adolphson, C.R. (2013). The eosinophilic leukocyte: structure and function. Advances in Immunology.
Rothenberg, M.E. (2006). Eosinophilia. New England Journal of Medicine.
Klion, A.D., & Nutman, T.B. (2004). The role of eosinophils in host defense against helminth parasites. Journal of Allergy and Clinical Immunology.
British Society for Haematology. (2019). Guidelines for the investigation and management of eosinophilia. British Journal of Haematology.
References
Gleich, G.J., & Adolphson, C.R. (2013). The eosinophilic leukocyte: structure and function. Advances in Immunology.
Rothenberg, M.E. (2006). Eosinophilia. New England Journal of Medicine.
Klion, A.D., & Nutman, T.B. (2004). The role of eosinophils in host defense against helminth parasites. Journal of Allergy and Clinical Immunology.
British Society for Haematology. (2019). Guidelines for the investigation and management of eosinophilia. British Journal of Haematology.
References
Gleich, G.J., & Adolphson, C.R. (2013). The eosinophilic leukocyte: structure and function. Advances in Immunology.
Rothenberg, M.E. (2006). Eosinophilia. New England Journal of Medicine.
Klion, A.D., & Nutman, T.B. (2004). The role of eosinophils in host defense against helminth parasites. Journal of Allergy and Clinical Immunology.
British Society for Haematology. (2019). Guidelines for the investigation and management of eosinophilia. British Journal of Haematology.
Research articles
Research articles
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