Background: Selective immunoglobulin A deficiency (SIgAD) represents the most frequently encountered form of primary immunodeficiency and is defined by markedly reduced circulating IgA concentrations despite normal IgG and IgM levels. This study aimed to characterize the clinical spectrum and laboratory profile of pediatric patients with SIgAD, with particular emphasis on allergic comorbidities and autoimmune manifestations.Methods: This retrospective observational study was conducted among children aged 4–18 years who met the European Society for Immunodeficiencies (ESID) diagnostic criteria for SIgAD between April 1, 2023, and December 1, 2025. Information on demographic variables, clinical features, and laboratory measurements was collected from electronic health records and analyzed using descriptive statistics.Results: Twenty-six pediatric patients were included (61.5% male). The median ages at symptom onset and diagnosis were 4.50 years (IQR, 3.0–6.0) and 6.97 years (IQR, 5.1–9.5), respectively. Recurrent infections affected 76.9% of patients and represented the predominant clinical manifestation. Allergic diseases were present in 73.1% of patients, most frequently asthma and allergic rhinitis; 42.3% showed aeroallergen sensitization, predominantly to pollens. Among the patients who underwent autoantibody screening, positivity was detected in approximately two-thirds; however, onlytwo were diagnosed with autoimmune diseases (thyroiditis and vitiligo). Antibiotic prophylaxis was initiated in 7.7% of patients due to recurrent infections.Conclusion: Although recurrent infections are the most common presentation in SIgAD, serum IgA evaluation should also be considered in patients with allergic or autoimmune conditions. Regular follow-up is necessary to monitor allergic manifestations, immunologic status, and the potential development of autoimmune diseases.
Çeli̇k et al. (Fri,) studied this question.