High serum APRIL levels strongly correlate with disease severity in pediatric atopic eczema

Expression of the tumor necrosis factor (TNF) family member APRIL (a proliferation-inducing ligand) is low in normal tissues but is elevated in various autoimmune diseases.

This study explored serum APRIL in children with atopic eczema (AE) during flare and quiescence.

A case-control study including 50 patients with AE and 40 control subjects was conducted. The severity of AE was assessed according to each of the Leicester Sign Score (LSS), the Simple Scoring System (SSS), the SCORing of Atopic Dermatitis (SCORAD) index, and the Objective SCORAD. Serum measurements of APRIL, total immunoglobulin E, and lactate dehydrogenase were obtained in all subjects. Data were obtained during both flare and quiescence in AE subjects. Data were analyzed using the Mann-Whitney U-test and Pearson's correlation coefficient. P-values of <0.05 were considered to indicate statistical significance.

Serum APRIL levels were significantly elevated in children with AE in comparison with control subjects during both flare and quiescence (P < 0.0001 for both). Serum APRIL levels during AE flare and quiescence were positively correlated (P < 0.001). Serum APRIL levels and scores on each of the LSS, SSS, and SCORAD showed significant positive correlations (P < 0.01 for all).

Serum APRIL levels were significantly elevated in children with AE during both flare and quiescence. This confirms the importance of APRIL in the pathophysiology of pediatric AE. Serum APRIL is a reliable marker of the severity of AE in children. APRIL may be a new target in the treatment of AE.