Correlation Between Serum 25-Hydroxyvitamin D Levels and Severity of Atopic Dermatitis in Children

Abstract

To determine if low levels of vitamin D correlate with the severity of atopic dermatitis (AD).Thirty-seven children (20 boys and 17 girls) with AD, between the ages of 8 months and 12 years, were evaluated in an outpatient clinic in Verona, Italy.The Severity Scoring of Atopic Dermatitis (SCORAD) index was used to determine the severity of AD in these children. Serum 25-hydroxyvitamin D (25[OH]D) levels were determined by using a chemiluminescent method. Values were used as a continuous variable, and vitamin D amounts were also categorized, in a descriptive analysis, as sufficient (≥30–40 ng/mL), insufficient (20–30 ng/mL), or deficient (<20 ng/mL). The ImmunoCAP test (Phadia, Uppsala, Sweden) was used to assay for specific immunoglobulin E (sIgE) to Staphylococcus aureus enterotoxins and to Malassezia furfur. Skin-prick testing was performed for common environmental and food allergens, and mean diameters were added together to create a total allergy score.Using the SCORAD index, subjects were classified as having severe (9 of 37), moderate (13 of 37), or mild (15 of 37) AD. Mean serum 25(OH)D levels were found to be significantly higher in patients with mild AD (36.9 ± 15.7 ng/mL) compared with those with moderate (27.5 ± 8.3 ng/mL) or severe AD (20.5 ± 5.9 ng/mL). Although not statistically significant, the prevalence of patients with sIgE to microbial antigens increased with the severity of AD and the presence of vitamin D deficiency. There was no significant difference in the total allergy scores between those with mild, moderate, and severe AD.Vitamin D deficiency might be related to the severity of AD.These results support the idea that vitamin D deficiency might be related to the severity of AD and adds to the current body of epidemiologic studies. The study also reinforces that studies that evaluate treatment of vitamin D deficiency and treatment with vitamin D for the management of AD are needed.