Implication of serum IgE in childhood nephrotic syndrome

Elevated serum IgE levels have been related to glomerular diseases. We investigated the relationship between serum total and specific IgE levels and their modulating factors [interleukin-4 (IL-4) and sCD23] and the outcome of childhood nephrotic syndrome (NS) after steroid treatment. We found that children with NS had significantly higher serum IgE levels than age-matched allergic patients and normal controls. Patients with steroid-resistant nephrotic syndrome (SRNS) had higher serum IgE levels than patients with steroid-sensitive nephrotic syndrome (SSNS) both pre and post treatment. Elevated initial serum IgE levels appeared to be associated with poor outcome. Although one-half of nephrotic children had detectable specific IgE to common allergens (dust mites or milk), the presence of specific IgE was not correlated with disease outcome. Serum IL-4 levels were not different among normal controls and patients with SRNS or SSNS. However, serum sCD23 levels in NS patients were significantly higher than in normal controls both pre and post treatment. Serum sCD23, but not IL-4, levels were correlated with serum total IgE levels. Our results suggest that regulation of total IgE production correlates with the disease activity and outcome of NS, although the presence of common specific IgE may not be linked to the pathogenesis.