Correlations of serum Interleukin-16, total IgE, eosinophil cationic protein and total eosinophil counts with disease activity in children with atopic dermatitis.

Several laboratory parameters have been investigated for assessing disease activity in children with atopic dermatitis (AD). Analyses of the correlation between these parameters and clinical severity can help to choose a convincing tool. This study compared the significance of serum interleukin-16 (IL-16), serum total immunoglobulin E (IgE), serum eosinophil cationic protein (ECP), and total eosinophil count (TEC) in reflecting AD severity to order to identify the most relevant objective tool for assessing AD activity and to assess the correlation between these laboratory parameters. The Severity Scoring of Atopic Dermatitis (SCORAD index) was used for the assessment of disease activity in 48 pediatric patients in the acute exacerbation phase and in the maintenance phase after improvement of clinical findings with conventional treatment for 8 weeks. Serum levels of total IgE, ECP, and IL-16 as well as TEC were measured on the same time points and compared with healthy non-atopic controls. The correlation between SCORAD and each laboratory parameter was tested for significance and compared. Serum levels of ECP and IL-16 of AD patients were significantly higher than those of controls. These serum parameters, except TEC, declined significantly after conventional treatment with clinical improvement. There was positive correlation with SCORAD for serum IgE (r=0.317, p=0.028), TEC(r=0.434, p=0.002), IL-16 (r = 0.321, p=0.026) in the acute exacerbation phase and with SCORAD for serum IgE (r=0.510, p<0.001), TEC(r=0.489, p<0.001), serum ECP (r=0.468, p=0.001) in the maintenance phase. Serum levels of total IgE, IL-16, ECP, and TEC correlated with the SCORAD index in pediatric patients with atopic dermatitis. Thus, they can serve as serum markers for monitoring disease activity in childhood atopic dermatitis.