METHODS: A case-control study was conducted with 32 participants who received narrowband ultraviolet B or ultraviolet A-1 therapy for various dermatological indications. Standardized skin surface biopsies were performed before and after phototherapy to assess Demodex density. The presence of Demodex-related skin conditions was assessed before phototherapy. A statistical analysis was performed to compare the Demodex densities and prevalence of demodicosis between the baseline and 20th session of phototherapy.
RESULTS: No significant change was observed in Demodex density after 20 sessions of phototherapy. The average Demodex density before treatment was 2.75 ± 4.48 (/cm2 ), and after treatment, it was 2.85 ± 4.81 (/cm2 ), indicating no significant difference (P = 0.879). The percentage of patients with demodicosis in at least one region of the face was 28.1% (9/32) before treatment, and after treatment, it was 31.3% (10/32), with no significant difference (P = 1.00).
CONCLUSIONS: Our findings contradict previous studies that suggested an increased Demodex density and demodicosis prevalence after phototherapy. The data from previous studies are open to debate due to their selected samples, designs, and interpretations regarding the phototherapy-immunosuppression-Demodex relationship. Larger-scale longitudinal studies conducted on a homogeneous sample are warranted to better understand the relationship between phototherapy and demodicosis.
方法:对32名接受窄带紫外线B或紫外线A-1治疗的参与者进行了病例对照研究。在光疗之前和之后进行标准化的皮肤表面活检以评估蠕形螨密度。在光疗之前评估蠕形螨相关皮肤状况的存在。进行统计分析以比较基线和第20次光疗之间的蠕形螨密度和蠕形螨病的患病率。
结果:20次光疗后,蠕形螨密度没有明显变化。治疗前平均蠕形螨密度为2.75±4.48(/cm2),治疗后,为2.85±4.81(/cm2),差异无统计学意义(P=0.879)。治疗前至少有一个面部区域的痴呆患者比例为28.1%(9/32),治疗后,它是31.3%(10/32),差异无统计学意义(P=1.00)。
结论:我们的发现与先前的研究相矛盾,先前的研究表明光疗后蠕形螨密度和蠕形螨病患病率增加。先前研究的数据因其选定的样本而存在争议,设计,以及关于光疗-免疫抑制-蠕形螨关系的解释。为了更好地了解光疗与去生物病之间的关系,有必要对均匀样品进行大规模的纵向研究。