From the Guidelines
The most common cause of elevated Immunoglobulin E (IgE) levels is allergic conditions, particularly atopic diseases such as allergic rhinitis, asthma, atopic dermatitis (eczema), and food allergies. When a person is exposed to an allergen, their immune system produces IgE antibodies as part of the hypersensitivity reaction. These IgE antibodies bind to mast cells and basophils, which then release histamine and other inflammatory mediators when re-exposed to the allergen, causing the typical allergic symptoms. Other causes of elevated IgE include parasitic infections (particularly helminth infections), certain immunodeficiency disorders like hyper-IgE syndrome (Job's syndrome), some malignancies, and specific inflammatory conditions 1.
Key Points to Consider
- The normal range for total serum IgE in adults is typically less than 150 IU/mL, though this can vary by laboratory 1.
- Identifying the specific cause of elevated IgE often requires clinical correlation with symptoms, additional laboratory testing, and sometimes allergen-specific IgE testing to determine the particular allergens triggering the immune response.
- Allergic disorders are the most common cause of secondary (reactive) eosinophilia, occurring in about 80% of cases, and parasitic infections represent the second most common cause 1.
- Certain immunodeficiency syndromes associated with abnormal immunoglobulin levels, such as hyperimmunoglobulin E syndrome, can also cause elevated IgE levels 1.
Diagnosis and Assessment
The diagnosis of the underlying cause of elevated IgE levels is essential to establish the appropriate treatment plan. It is important to rule out secondary (reactive) causes, such as allergies, infections, autoimmune or inflammatory disorders, and neoplastic conditions 1. A comprehensive diagnostic approach, including clinical evaluation, laboratory testing, and sometimes allergen-specific IgE testing, is necessary to determine the specific cause of elevated IgE levels.
Management and Treatment
Management and treatment of elevated IgE levels depend on the underlying cause. For allergic conditions, avoidance of the allergen and treatment with antihistamines, corticosteroids, or immunotherapy may be necessary 1. For parasitic infections, treatment with antiparasitic medications is essential 1. In cases of immunodeficiency syndromes or malignancies, treatment of the underlying condition is crucial.
From the Research
Causes of Elevated Immunoglobulin E (IgE) Levels
- Elevated IgE levels can be caused by various factors, including allergies, infections, and immune conditions 2, 3, 4
- Atopic diseases, such as atopic dermatitis and bronchial asthma, are the most common causes of elevated IgE levels 3, 4
- Other conditions that can lead to elevated IgE levels include parasitic diseases, malignancy, and hyper-IgE syndrome (HIES) 4
- IgE-mediated multimorbidities, such as allergic rhinitis, rhinoconjunctivitis, and food allergies, can also contribute to elevated IgE levels 5
Relationship Between IgE Levels and Underlying Conditions
- High IgE levels are often associated with severe allergic diseases, such as atopic dermatitis and asthma 2, 6
- Extremely elevated IgE levels can indicate an underlying inborn error of immunity or a monogenic atopic disorder 3
- However, elevated IgE levels are not always predictive of a specific underlying condition, such as HIES 4