Korean J Lab Med.  2007 Apr;27(2):128-132. 10.3343/kjlm.2007.27.2.128.

Clinical Significance of Serum Interleukin-18 Concentration in the Patients with Atopic Dermatitis

• Park DS
• Youn YH

• KMID: 1781472
• DOI: http://doi.org/10.3343/kjlm.2007.27.2.128

Abstract

BACKGROUND: Interleukin (IL)-18, a potent inducer of interferon gamma (IFN-gamma), is known to have a role in diseases involving type-2 T helper cell responses including atopic dermatitis. In this study, we aimed to determine the clinical significance of serum IL-18 level in the patients with atopic dermatitis. METHODS: Serum concentration of IL-18, IFN-gamma, IgE, and blood eosinophil were measured in the patients with atopic dermatitis and healthy control subjects, and their association with the clinical score of the disease was analysed. RESULTS: Serum concentrations of IL-18 were significantly elevated in patients with atopic dermatitis compared to the healthy controls (332 pg/mL vs 151 pg/mL, P<0.05). Serum levels of IL-18 (r=0.41, P=0.001), eosinophil (r=0.36, P=0.003), and IgE (r=0.32, P=0.009) correlated with clinical scores in the patients. Also, multiple regression analysis indicated that serum IL-18 and IgE levels were independent predictors for the clinical score of atopic dermatitis (r2=0.25, beta=0.39, P=0.001 and beta=0.32, P=0.009). CONCLUSIONS: Our results confirmed a significant correlation between the concentration of serum IL-18 and the severity of atopic dermatitis. Although serum IL-18 concentration reflects the disease severity, its usefulness as a clinical test needs to be further investigated, because its additive benefit over those of conventional blood tests is not evident so far.

Keyword

Interleukin 18; Atopic dermatitis; Cytokine

MeSH Terms

Adolescent
Adult
Child
Child, Preschool
Dermatitis, Atopic/*diagnosis
Female
Humans
Immunoglobulin E/blood
Interleukin-18/*blood
Male
ROC Curve
Severity of Illness Index

Figure

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  Fig. 1. Mean concentrations (rectangles) and 95% confidence intervals (error bars) of blood eosinophil, IgE, IL-18, and IFN-γ in healthy controls, total atopic dermatitis (AD), and each disease grade group (mild, moderate, and severe) of AD.

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  Fig. 2. ROC curve analysis for the screening efficiency of serum IL-18.

Reference

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