Improve the dupilumab therapy evaluation with dermoscopy and high-frequency ultrasound in moderate-to-severe atopic dermatitis.

Background: Atopic dermatitis (AD) is a chronic inflammatory disease. Monoclonal antibody dupilumab was approved to treat moderate-to-severe AD in recent years. An objective assessment of treatment response by skin imaging modality is adjuvant for clinical evaluations. This study aimed to explore the value of dermoscopy and high-frequency ultrasound (HFUS) imaging characteristics in treatment evaluation for moderate-to-severe AD patients treated with dupilumab.

Methods: Moderate-to-severe AD patients refractory to conventional therapy were enrolled in the study. All patients went through at least a 16-week standardized treatment of dupilumab. Clinical scores (eczema area scoring index [EASI], SCOARD, numerical rating scale of pruritus, dermatology life quality index), dermoscopy, and HFUS examinations were conducted at 0, 2, 4, 8, 12, and 16 weeks of treatment. Erythema, scales, erosion, and pigmentation under dermoscopy were scored, and subepidermal low-echogenic band (SLEB) thickness under HFUS was measured as quantitative indexes. Descriptive analysis and mixed effect linear regression models were used for statistical analysis.

Results: Sixteen patients were enrolled in the study and their average age was 45.63 ± 18.18 years. All clinical scores decreased with significant difference after 16-week treatment compared with baseline. All patients achieved EASI 50 (EASI score decreased by 50% or more), and 9/16 patients reached EASI 75 after 16-week treatment. Dermoscopy evaluation of erythema, scales and erosion scores were decreased, and the sign of pigmentation score was increased after treatment. For HFUS, the mean SLEB value was 0.51 ± 0.29 mm and decreased to 0.27 ± 0.15 mm after 16-week treatment (p < 0.01). SLEB value decreased linearly with treatment time and correlated with clinical scores. However, SLEB values of two patients were 0.57 and 0.68 mm at week 16, respectively, which were higher than the average, and one of the patients showed EASI 75.

Conclusion: Dermoscopy and HFUS were able to reveal deeper inflammation response than clinical scores in AD and can be an effective method to evaluate and monitor clinical improvement during dupilumab treatment for AD patients. The preliminary value of imaging methods for predicting the treatment endpoint of dupilumab remains to be verified.