Follow-up and outcome of symptomatic partial or absolute IgA deficiency in children

Selective IgA deficiency is defined as absolute or partial when serum IgA level is < 7 mg/dl or 2 SD below normal for age, respectively. Few data are available on partial selective IgA deficiency, as probably most children with low serum IgA are seldom referred to a specialist clinic in common pediatric practice. The aim of our study was to better define the profile of both symptomatic forms and their clinical outcome in a pediatric immunology setting. Thus, clinical and immunological data from 103 symptomatic patients with selective IgA deficiency (53 absolute and 50 partial), 4-18 years of age, were collected at diagnosis and 80 patients (44 absolute and 36 partial) were monitored for a mean period of 5 years. Also, the prevalence of TNFRSF13B mutations has been assessed in 56 patients. The most common clinical features were infections (86/103; 83%), allergy (39/103; 38%), and autoimmunity (13/103; 13%). No significative differences were observed between absolute and partial selective IgA deficiency patients. However, a significative difference in the rate of IgA normalization between partial and absolute selective IgA deficiency patients (33 vs 9%, p = 0.01) was detected. Furthermore, a lower incidence of infections was associated to a normalization reversal compared to a final absolute or partial defect status (12 vs 53 and 64% respectively, p < 0.01).