[Clinical phenotypes associated with selective IgA deficiency: a review of 330 cases and a proposed follow-up protocol].
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Selective IgA deficiency is the most common Primary Immune Deficiency. Only a small proportion of these patients present during childhood, but this proportion increases over the years, and may be associated with an IgG subclass deficiency with increased susceptibility to respiratory and digestive tract infections. During childhood, IgA deficient patients may also refer to symptoms related to allergic and autoimmune diseases or tumours.To describe the relationship of selective IgA deficiency with infections, allergic diseases, autoimmune disorders and tumours. To investigate the presence of other immune disorders associated with selective IgA deficiency. To suggest a follow-up protocol for these patients.Retrospective study of paediatric patients (<18 years) being followed-up in the Clinical Immunology Department between 1992 and 2007, as well as laboratory records with IgA values below 50mg/L. Clinical records were reviewed (frequency and intensity of diseases associated with selective IgA deficiency) along with immunology tests performed.A total of 330 paediatric patients were identified with a selective IgA deficiency: 39 (11.8%) suffered from recurrent ear infections (2 developed secondary deafness), 58 (17.5%) from recurrent upper respiratory tract infections, and 20 patients (6%) from recurrent pneumonia, 6 of whom developed secondary bronchiectasis and 2 underwent a lobectomy. A relationship with atopic disease was found in 62 (18.78%) of patients. Regarding digestive disorders, chronic diarrhoea was found in 21 (6.5%), coeliac disease in 22 (6.6%), and persistently high plasma transaminases in 3. Autoimmune manifestations were found in 38 (11.5%), juvenile chronic arthritis, type 1 diabetes, vitiligo, cytopenia, and Crohn's disease, amongst others). Tumours were identified in 5 (1.5%). An IgG sub-class deficiency was found in 5 patients (4%), and 6 patients had a confirmed deficiency in antibody production.In our cohort, 56.6% of patients with IgA deficiency showed other comorbidities which were, in decreasing frequency: recurrent infections (respiratory and ear infections), allergic diseases, autoimmunity and tumours. Some patients will develop a more severe humoral defect (IgG subclass deficiency with or without antibody deficiency).
