D3.368 - Selective IgE Deficiency in Children: 10-Year Experience

Selective IgE deficiency (sIgED) is defined as a serum total IgE level of <2.5 IU/mL with other immunoglobulin levels (IgG, IgA, IgM) within the normal range for age. In limited studies, associations with atopy, autoimmunity, and malignancy have been reported. This study evaluated the demographic and clinical characteristics of pediatric sIgED cases.

In this single-center retrospective study, 14,000 patients aged 4–18 years who presented between 01/01/2014 and 12/31/2024 and had IgG, IgA, and IgM levels measured together with total IgE in the same evaluation were screened. Cases with age-normal IgG/IgA/IgM values and total IgE <2.5 IU/mL on at least two measurements were considered sIgED. Demographic data and accompanying clinical conditions were analyzed.

The mean age of 305 patients was 10.42±3.82 years (range, 4–18), and 54.8% were female. The mean total IgE level was 1.66±0.53 (min–max: 0.90–2.49). Allergic disease was present in 48.1% of cases; the distribution was asthma 18.4%, allergic rhinitis 16.7%, coexisting asthma and allergic rhinitis 5.2%, atopic dermatitis 2.6%, urticaria 2.3%, food allergy 1.0%, and antibiotic allergy 1.0%. Urinary system anomalies were the most frequent (10.8%), followed by endocrine disorders (5.9%), cardiac defects (5.5%), rheumatologic diseases (5.2%), neurologic disorders (4.2%), syndromic conditions (3.9%), gastrointestinal diseases (3.6%), autoimmune diseases (1.6%), congenital inborn errors of immunity (1.6%) and malignancy (1.0%). No accompanying disease was present in 32.1% of patients. No significant correlation was observed between total IgE level and accompanying diseases.

n this study covering a broad time period, despite low total IgE levels, the rate of allergic diseases was high, and similar to previous studies, the frequent occurrence of malignancy and autoimmune diseases, cardiac defects, and additionally urinary system defects highlights the importance of systematic evaluation in sIgED cases.