D3.354 - Selective IgE deficiency in children: its role in autoimmunity
Background
Immunoglobulin E (IgE) is a part of the immune system best known for its probable beneficial role in host defense against parasitic infections and its detrimental effect in allergic diseases. Reports have shown that selective IgE deficiency may contribute to the onset of non-allergic diseases such as autoimmune disorders or malignancy.
Method
We retrospectively studied 76 non-atopic children (23 boys) with low levels or deficiency of serum IgE. The IgE levels were defined as low (5-10 IU/ml) or deficiency (<5 IU/ml). These patients were contacted in adolescence and IgE levels were re-evaluated, defined as normal (>10 IU/ml), low level or IgE deficiency. During the follow-up, data on the patients’ medical history was recorded.
Results
Among the children studied, 51 patients (67,1%) were preschoolers and 25 (32,9%) were children of school-age that were referred to our pediatric allergic clinic due to recurrent respiratory tract symptoms (92,1%) and chronic urticaria (7,9%). A simple immunologic screening that included CBC, ESR, CRP and serum concentrations of immunoglobulins G, A, M and E was performed. At the initial evaluation 49 patients (64,5 %) had low levels of IgE, while 27 of them (35,5 %) were IgE deficient. During the follow up, at a mean age of 12 (± 2.5) years, IgE was measured within normal levels in 43 patients (56,6 %), within low levels in 13 of them (17,1 %) and 20 children (26,3 %) were detected with IgE deficiency. 18 patients (66,7%) with initial IgE deficiency remained deficient. In addition, autoimmunity (including Hashimoto thyroiditis, celiac disease, chronic urticaria and Diabetes Mellitus type 1) was reported in 17 (22,3 %) of the initial group of patients and persistent deficiency was recorded in 10/17 (58,8%). No malignancy was recorded.
Conclusion
Most children with low IgE levels manage to overcome and reach normal in adolescence. On the contrary, IgE deficiency seems to persist in most cases. A substantial number of children that remained deficient developed an autoimmune disorder.
