From the Guidelines
For a patient with an elevated IgE level of 3000, a comprehensive workup should be initiated to determine the underlying cause, starting with a detailed clinical history and physical examination, followed by laboratory testing including complete blood count with differential, specific IgE testing, and consideration of parasitic infections, asthma, and primary immunodeficiency syndromes 1. The workup should prioritize identifying potential allergic, infectious, or immunodeficiency causes, given the broad range of conditions associated with elevated IgE levels.
- Key aspects of the clinical history should include:
- Allergic symptoms
- Family history of atopy
- Recurrent infections
- Skin conditions
- Physical examination should assess for:
- Dermatologic manifestations like eczema, urticaria, or angioedema
- Laboratory testing should include:
- Complete blood count with differential to look for eosinophilia
- Specific IgE testing to common allergens
- Skin prick testing if appropriate
- Evaluation for parasitic infections with stool studies and serologies, particularly if there's travel history to endemic areas
- Additional testing may be warranted based on clinical suspicion, including:
- Pulmonary function tests if asthma is suspected
- Genetic testing for conditions like hyper-IgE syndrome (Job's syndrome) or Wiskott-Aldrich syndrome if primary immunodeficiency is considered
- Chest imaging to evaluate for bronchiectasis or fungal infections Given the non-specific nature of elevated IgE levels, which can be found in about 55% of the general population and in various non-atopic conditions such as parasitic infections, certain cancers, and autoimmune diseases 1, a thorough and stepwise approach is necessary to guide appropriate treatment strategies.
From the Research
Workup for Elevated Immunoglobulin E (IgE) Levels
Elevated IgE levels can be an indicator of various conditions, including parasitic infections, allergic reactions, or autoimmune conditions 2. A workup for a patient with elevated IgE levels of 3000 may involve the following steps:
- Total IgE determination: This is a good method for screening atopic diseases, although its actual value is controversial 3.
- Specific IgE determination: This can help identify the responsible allergen, but the results can vary significantly depending on the method used and the type of allergen 3.
- Clinical history and physical examination: A thorough clinical history and physical examination can help identify symptoms and signs of underlying conditions, such as atopic dermatitis or bronchial asthma 4.
- Laboratory investigations: These may include measurements of IgG, IgA, IgM, and IgG subclasses, as well as serological tests and imaging studies to rule out underlying infections or other conditions 2, 4.
- Genetic testing: In cases where an inborn error of immunity is suspected, genetic testing can help identify specific genetic abnormalities and provide insight into the immunopathogenesis of the disease 5, 6.
Possible Underlying Factors
Elevated IgE levels can be caused by various underlying factors, including:
- Allergic diseases: Such as atopic dermatitis, bronchial asthma, and food allergies 3, 4.
- Inborn errors of immunity: Such as hyper-IgE syndrome, which can be caused by genetic mutations in genes such as STAT3, FLG, DOCK8, SPINK5, and CARD11 5, 6.
- Parasitic infections: Such as toxocariasis, which can cause elevated IgE levels and eosinophilia 2.
- Recurrent infections: Which can be a hallmark of underlying immunodeficiency or inborn error of immunity 6.