特应性皮炎患者血清维生素D检测及其临床意义

Detection of vitamin D in sera of patients with atopic dermatitis and its clinical significance

目的 检测特应性皮炎（AD）患者血清中维生素D（VitD）、总免疫球蛋白E（tIgE）、白细胞介素4（IL-4）、IL-6水平，评价VitD与AD患者病情严重程度的关系及其在AD发病中炎症与免疫调节中的作用。方法 采集37例AD组和30例对照组外周血，检测血清VitD、tIgE、IL-4、IL-6水平，通过SCORAD评分评估AD患者病情严重程度。采用t检验或U检验分析组间差异，采用χ^2检验比较VitD缺乏、不足与充足患者比例，采用Pearson或Spearman相关进行各组间的相关性分析。结果 AD组血清VitD水平［（24.77 ± 9.29） μg/L］低于对照组［（28.98 ± 6.87） μg/L，t = 2.015，P = 0.048］，tIgE水平［137.68（37.59 ~ 414.53） IU/ml］高于对照组［45.16（14.56 ~ 112.12） IU/ml，Z = -3.399，P = 0.001］，IL-4水平［（8.86 ± 4.83） ng/L］高于对照组［（4.78 ± 3.07） ng/L，t = 4.147，P 〈 0.001］，IL-6水平［6.53（3.99 ~ 15.30） ng/L］高于对照组［4.58（2.85 ~ 8.17） ng/L，Z = -2.173，P = 0.030 ］。AD组SCORAD评分与血清VitD水平负相关（r = -0.505，P = 0.001），与tIgE、IL-4水平正相关（r值分别为0.531、0.519，P值均为0.001），与IL-6无相关性（r = -0.139，P = 0.411）。AD组与对照组相比，VitD缺乏、不足与充足患者比例差异有统计学意义，χ2 = 8.762，P = 0.013。VitD缺乏患者血清tIgE［2846.87（319.02 ~ 7300.00） IU/ml］与IL-4水平［（16.37 ± 2.05） ng/L］分别高于VitD不足［110.07（26.20 ~ 501.48） IU/ml，P = 0.045；（8.28 ± 4.48） ng/L，P = 0.011］和VitD充足患者［123.93（91.61 ~ 273.68） IU/ml，P = 0.024；（8.00 ± 4.63） ng/L，P = 0.041］。VitD缺乏患者IL-6水平［15.10（8.49 ~ 30.72） ng/L］高于充足［6.22（4.47 ~ 9.47）ng/L，P = 0.011］。结论 AD患者存在VitD缺乏或不足，VitD缺乏与高水平tIgE、IL-4、IL-6有关，且AD的严重程度与tIgE、IL-6升高及VitD降低关系密切。

Objective To measure the serum levels of vitamin D, total immunoglobulin E （tIgE）, interleukin-4 （IL-4） and IL-6 in patients with atopic dermatitis （AD）, to evaluate the association between vitamin D and severity of AD, and to investigate the role of vitamin D in inflammatory and immunoregulatory processes during the occurrence of AD. Methods Peripheral blood samples were collected from 37 patients with AD （AD group） and 30 healthy controls （control group）. The serum levels of vitamin D, tIgE, and IL-6 were measured by chemiluminescent sandwich enzyme immunoassay, and those of IL-4 by enzyme-linked immunosorbent assay. The severity of AD was assessed by the SCORing atopic dermatitis （SCORAD） score. The t test or Mann-Whitney U test was performed to assess the differences in vitamin D, tIgE, IL-4 and IL-6 levels between the AD group and control group, chi-square test to compare the proportion of patients with vitamin D deficiency, insufficiency and sufficiency, and Pearson′s correlation analysis or Spearman′s correlation analysis to evaluate the correlations between the SCORAD score and serum levels of vitamin D, tIgE, IL-4 and IL-6. Results Compared with the control group, the AD group showed significantly decreased serum levels of vitamin D （24.77 ± 9.29 vs. 28.98 ± 6.87 μg/L, t = 2.015, P = 0.048）, but significantly increased serum levels of tIgE （137.68 [37.59 - 414.53] vs. 45.16 [14.56 - 112.12] IU/ml, Z = -3.399, P = 0.001）, IL-4 （8.86 ± 4.83 vs. 4.78 ± 3.07 ng/L, t = 4.147, P 〈 0.001） and IL-6 （6.53 [3.99 - 15.30] vs. 4.58[2.85 - 8.17] ng/L, Z = -2.173, P = 0.030）. Among patients with AD, the SCORAD score was negatively correlated with serum levels of vitamin D （r = -0.505, P = 0.001）, positively correlated with those of tIgE （r = 0.531, P = 0.001） and IL-4 （r = 0.519, P = 0.001）, but uncorrelated with those of IL-6 （r = -0.139, P = 0.411）. There were significant differences in the proportion of patients with vitamin D deficiency, insufficiency and sufficiency between the AD group and control group （χ2 = 8.762, P = 0.013）. AD patients with vitamin D deficiency showed significantly increased serum levels of tIgE （2846.87 [319.02 - 7300.00] IU/ml） and IL-4 （ [16.37 ± 2.05] ng/L） compared with those with vitamin D insufficiency （110.07 [26.20 - 501.48] IU/ml, P = 0.045; [8.28 ± 4.48] ng/L, P = 0.011） and those with vitamin D sufficiency （123.93 [91.61 - 273.68] IU/ml, P = 0.024; [8.00 ± 4.63] ng/L, P = 0.041）. In addition, serum levels of IL-6 were also higher in patients with vitamin D deficiency than in those with vitamin D sufficiency （15.10 [8.49 - 30.72] vs. 6.22 [4.47 - 9.47] ng/L, P = 0.011]. Conclusions Vitamin D deficiency or insufficiency exists in patients with AD. Vitamin D deficiency is correlated with high serum levels of tIgE, IL-4 and IL-6, and the severity of AD is closely correlated with increased serum levels of tIgE and IL-6 as well as decreased serum levels of vitamin D.