摘要Objective::Pityriasis versicolor (PV) is usually a clinical diagnosis. In uncertain cases, PV is confirmed by microscopic examination with 10% potassium hydroxide (KOH). However, the KOH test is not 100% sensitive in diagnosing PV. Dermoscopy of PV is still an unexplored area with very little data reported. This study was planned to study the various dermoscopic features and their utility in the diagnosis of PV.Methods::This cross-sectional observational study was carried out over a 1-year period (September 2020– September 2021) among 57 patients with KOH-confirmed PV. All patients underwent dermoscopy using a handheld dermoscope (DermLite DL4; DermLite LLC). The chi-square test or Fisher’s exact test was used to analyze the data.Results::Of the 57 patients, 43 (75.44%) had the hypopigmented type, followed by the hyperpigmented type ( n = 12, 21.05%) and the perifollicular type ( n = 2, 3.51%). Nonuniform pigmentation was the most common dermoscopic finding observed in both patients with hypopigmented PV ( n = 42, 97.67%) and hyperpigmented PV ( n = 12, 100%) ( P = 0.001). Scaling was the second most commonly observed finding; patchy scaling ( n = 25, 58.13%) and perifollicular scaling ( n = 13, 30.23%) were commonly seen in hypopigmented PV, while hyperpigmented PV showed more diffuse scaling ( n = 6, 50.00%) ( P = 0.04) followed by patchy scaling ( n = 5, 41.66%). Dermoscopy showed unique "double-edged scales" in all lesions with furrow scaling ( n = 11, 19.30%) after eliciting a positive evoked scale sign. Other interesting features seen in hypopigmented PV were hypopigmentation around the hair follicle ( n = 24, 55.48%) ( P = 0.001) and perilesional hyperpigmentation (the halo sign) ( n = 15, 34.88%) ( P = 0.04). Conclusion::We observed several dermoscopic findings in PV that can serve as useful clues for differentiating PV from other similar disorders.

abstractsObjective::Pityriasis versicolor (PV) is usually a clinical diagnosis. In uncertain cases, PV is confirmed by microscopic examination with 10% potassium hydroxide (KOH). However, the KOH test is not 100% sensitive in diagnosing PV. Dermoscopy of PV is still an unexplored area with very little data reported. This study was planned to study the various dermoscopic features and their utility in the diagnosis of PV.Methods::This cross-sectional observational study was carried out over a 1-year period (September 2020– September 2021) among 57 patients with KOH-confirmed PV. All patients underwent dermoscopy using a handheld dermoscope (DermLite DL4; DermLite LLC). The chi-square test or Fisher’s exact test was used to analyze the data.Results::Of the 57 patients, 43 (75.44%) had the hypopigmented type, followed by the hyperpigmented type ( n = 12, 21.05%) and the perifollicular type ( n = 2, 3.51%). Nonuniform pigmentation was the most common dermoscopic finding observed in both patients with hypopigmented PV ( n = 42, 97.67%) and hyperpigmented PV ( n = 12, 100%) ( P = 0.001). Scaling was the second most commonly observed finding; patchy scaling ( n = 25, 58.13%) and perifollicular scaling ( n = 13, 30.23%) were commonly seen in hypopigmented PV, while hyperpigmented PV showed more diffuse scaling ( n = 6, 50.00%) ( P = 0.04) followed by patchy scaling ( n = 5, 41.66%). Dermoscopy showed unique "double-edged scales" in all lesions with furrow scaling ( n = 11, 19.30%) after eliciting a positive evoked scale sign. Other interesting features seen in hypopigmented PV were hypopigmentation around the hair follicle ( n = 24, 55.48%) ( P = 0.001) and perilesional hyperpigmentation (the halo sign) ( n = 15, 34.88%) ( P = 0.04). Conclusion::We observed several dermoscopic findings in PV that can serve as useful clues for differentiating PV from other similar disorders.