Abstract
BACKGROUND: Acne vulgaris is a chronic inflammatory disorder of the pilosebaceous unit. Accurate and objective assessment of inflammatory activity remains a challenge in clinical practice. Dermoscopy, as a noninvasive imaging technique, enables visualization of vascular and color changes associated with inflammation. METHODS: In this cross-sectional study, 40 patients with mild-to-moderate acne vulgaris were enrolled, and 80 dermoscopic images were obtained. Background color, vascular morphology, vascular distribution, and perifollicular yellow halo were analyzed and compared between severity grades (mild vs. moderate) and among lesion types (comedonal, papular, pustular). RESULTS: In the mild group, a light-red background predominated (41.7%), whereas red and dark-red backgrounds were more common in the moderate group (both 38.6%), with a significant difference (χ(2) = 10.13, P = 0.006). Vascular morphology suggested a trend toward transition from dotted to branched forms with increasing inflammation, although this did not reach statistical significance (P > 0.05). By lesion type, comedonal lesions mainly displayed light-red backgrounds with dotted vessels, while papular and pustular lesions exhibited red-to-dark-red backgrounds with branched or atypical vessels (P < 0.05). CONCLUSION: Progressive deepening of background color and transformation of vascular morphology on dermoscopy are associated with increasing inflammatory activity in acne vulgaris. Quantitative evaluation of these dermoscopic parameters may contribute to preliminary objective severity grading and therapeutic monitoring. Dermoscopy may represent a potentially valuable, noninvasive imaging modality for assessing inflammatory activity in acne.