IgE deficiency may indicate underlying hypogammaglobulinaemia?

Area of Science:

• Clinical Immunology
• Allergy Diagnostics

Background:

• Low serum immunoglobulin E (IgE) levels (<2 kU/L) during allergy investigations can signal underlying immunodeficiency states.
• Common variable immunodeficiency (CVI) is characterized by recurrent respiratory infections, potentially leading to irreversible lung damage.

Purpose of the Study:

• To determine the prevalence of low serum IgE levels in allergy investigations.
• To assess the utility of low serum IgE as a screening marker for hypogammaglobulinemia or CVI.

Main Methods:

• Retrospective analysis of 4013 serum samples over 12 months to identify those with IgE < 2 kU/L.
• Review of subsequent serum immunoglobulin quantification and electrophoresis results for identified samples.

Main Results:

• 1.84% (74/4013) of samples had serum IgE < 2 kU/L.
• Of 18 samples with further testing, 56% (10/18) showed abnormal immunoglobulin levels, with two new diagnoses of immunodeficiency.

Conclusions:

• Very low serum IgE (<2 kU/L) is a potential marker for hypogammaglobulinemia and CVI.
• Early identification of immunodeficiency through further testing (serum protein electrophoresis, immunoglobulin quantification) is vital to reduce morbidity and mortality.