Objectives: The objective of the study is to evaluate the dermoscopic features of various hyperpigmentary dermatoses and determine their utility in differentiating between clinically similar conditions. Materials and Methods: A hospital-based, observational, cross-sectional study was conducted in the Department of Dermatology, Venereology, and Leprosy, Government Medical College and Sir T Hospital, Bhavnagar, from April 1, 2023, to March 31, 2024, after obtaining approval from the Institutional Ethics Committee (EC No. 1241/2023). Patients presenting with hyperpigmented lesions were enrolled after obtaining written informed consent. Detailed demographic and clinical information were recorded, and cases were categorized as epidermal, dermal, or mixed-type hyperpigmentation. Dermoscopic examination was performed on lesional skin using the DermLite DL5 dermoscope (3Gen Inc., San Juan Capistrano, California, USA) under both polarized and nonpolarized modes at ×10 magnification. Dermoscopic parameters, including pigment network, dots and globules, vascular structures, follicular and eccrine changes, and scaling patterns, were systematically documented. The data were entered into Microsoft Excel (Microsoft Corporation, Redmond, Washington, USA) and analyzed descriptively, with results expressed as frequencies and percentages to identify characteristic dermoscopic features of individual hyperpigmentary dermatoses. Results: Distinct dermoscopic features were identified across various hyperpigmentary dermatoses. Epidermal dermatoses showed characteristic patterns, with acanthosis nigricans demonstrating a sulci-gyral pattern (100%) with brown dots (67%) and eccrine accentuation (33%), Becker’s nevus showing a reticuloglobular pattern (100%) with perifollicular sparing (86%), and café-au-lait macules revealing a reticular pattern (100%) with patchy brown pigmentation (67%). Mixed-type dermatoses included epidermal melasma with patchy brown pigmentation (100%), arcuate structures (50%), and a reticuloglobular pattern (42%); lichen planus pigmentosus with fine gray dots (86%), peri-eccrine pigmentation (50%), and a Chinese-letter pattern (23%); and Riehl’s melanosis with perieccrine pigmentation (67%), perifollicular white scales (33%), and pseudo-network (33%). Dermal dermatoses showed distinctive features, with dermal melasma revealing a diffuse blue–gray background and brown globules (100%), nevus of Ota showing a uniform blue-gray background (100%) with blotches (75%) and clods (25%), and Mongolian spots exhibiting a homogeneous blue-gray background with eccrine accentuation (100%). Other findings included lichen amyloidosis displaying a hub-and-spoke pattern (100%), macular amyloidosis showing a reticuloglobular pattern (33%), pigmented purpuric dermatoses demonstrating red globules (100%) and yellow-orange areas (75%), seborrheic keratosis exhibiting comedo-like openings and cerebriform appearance (100%), and exogenous ochronosis showing a worm-like pattern (87.5%) with brown globules (62.5%). Conclusion: Distinct dermoscopic patterns were observed across different hyperpigmentary dermatoses, highlighting the value of dermoscopy in their evaluation and differentiation. Dermoscopy provides a reliable, non-invasive approach that enhances diagnostic accuracy and supports appropriate clinical management of hyperpigmentation.
Prajapati et al. (Fri,) studied this question.