Evaluation of diagnostic accuracy of dermoscopy in some common hypopigmented skin diseases

Diagnosis of cutaneous hypopigmentation can sometimes be challenging. Dermoscopy may play a role in identifying hypo or-depigmented dermatoses. The aim was to investigate which dermoscopic criteria represent potent indicators for the diagnosis of vitiligo, nevus depigmentosus, pityriasis alba, hypopigmented pityriasis versicolor, idiopathic guttate hypomelanosis, hypopigmented mycosis fungoides (MF), lichen sclerosus et atrophicus and ash leaf hypopigmented macules of tuberous sclerosis, and evaluate their diagnostic accuracy. 168 individuals diagnosed with one of these hypopigmented disorders were evaluated for the presence or absence of predetermined dermoscopic criteria. Evaluation of dermatoscopic characteristics in each condition and analysis for sensitivity and specificity of dermatoscopic diagnosis in these hypopigmented lesions was performed. The starburst pattern, micro-koebnerization, and trichrome pattern were unique to vitiligo diagnosis. Vitiligo had higher comet-tail appearance, perifollicular pigmentation, and perilesional hyperpigmentation than other hypopigmented illnesses. Other hypopigmented lesions had greater incidence of amoeboid pattern, faint or diminished pigment network, islands of pigmentation, ill-defined boundaries, pseudopods, and widespread scaling than vitiligo. Finally, perifollicular scaling, comedo-like openings, blue-gray specks, and fibrotic regions excluded vitiligo. Dermoscopy can help identify common hypopigmented skin lesions and reduce the need for skin biopsy. Nevus depigmentosus, pityriasis alba and idiopathic guttate hypomelanosis were the top three hypopigmented dermatoses that could be diagnosed by dermoscopy with 100% sensitivity. Vitiligo was in the second rank (94.7%), followed by lichen sclerosis et atrophicus (93.3%) then hypopigmented MF at 81.2% sensitivity. Dermoscopy sensitivity was lowest in pityriasis versicolor and ash leaf macules of tuberous sclerosis (52.6% and 46.7%, respectively).