Table 1.

Differential diagnosis of pityriasis versicolor.

Condition	Clinical Characteristics	Dermatoscopy
Hypopigmented Disorders
Pityriasis alba [55,56]	Flat, acquired roundish, asymptomatic hypopigmented macules with a subtle scaling, often located on the facial skin in children and adolescents.	Poorly demarcated hypopigmented areas covered with fine scales (lamellar or branny).
Vitiligo [51,56]	Flat, acquired and persistent, uni- or bilateral, well-demarcated hypopigmented roundish or linear macules.	Well-demarcated, non-scaly, diffuse white areas, usually accompanied with perifollicular hyperpigmentation and leukotrichia.
Idiopathic guttate hypomelanosis [51,56]	Flat, acquired hypo- or depigmented, variably sized roundish or polygonal macules predominantly located on sun-exposed sites and sparing the face.	Numerous well- to poorly defined hypopigmented areas characterised by various shades of white, bordering randomly distributed hyperpigmented reticular lines (cloudy sky-like pattern).
Leprosy (borderline or borderline tuberculoid) [56,57]	Distinct, acquired, circular, erythematous plaques with well-defined edges, forming a saucer-like shape, where the margins slope inside.	Orange-yellow or white structureless areas, with reduced number of hair units/follicular and eccrine ostia (white clods and dots, respectively). Orange clods, and vascular polymorphism (lines serpentine, clods, dots) can be present in some cases.
Progressive macular hypomelanosis [58]	Flat, acquired, symmetrically distributed, coalescing, non-scaly hypopigmented macules affecting the trunk and back.	Disseminated folliculocentric depigmented areas displaying subtle pigmentation of reticular lines. If present, delicate white scales are mainly restricted to skin creases.
Ash leaf macules in tuberous sclerosis [56,59]	Congenital, flat lanceolate depigmented macules present in tuberous sclerosis or isolated.	Poorly demarcated depigmented areas. Subtle background reticular lines are preserved.
Nevus depigmentosus [51,56]	Congenital, asymptomatic flat pale macules with fixed shape, typically present at birth.	Poorly defined hypopigmented area with subtle faded physiological reticular lines of background pigmentation and peripheral islands of normal-coloured skin.
Nevus anemicus [56,60]	Congenital, segmental flat area of depigmentation.	Poorly defined whitish area surrounded with red peripheral zone that often feature linear serpentine vessels.
Extragenital lichen sclerosus [51,56]	Acquired, usually asymptomatic, flat-topped papules or plaques affecting the trunk or/and extremities.	Well-delineated structureless white-yellowish areas. Active lesions feature typical yellowish follicular plugs. Diffuse white scale, polarising-dependent white structures (lines, areas, 4-dotted clods, and rainbow pattern), haemorrhages, dotted, linear serpentine and/or branching vessels can be present.
Hypopigmented mycosis fungoides [56,61]	Acquired, patchy hypopigmented areas.	Poorly defined hypopigmented pink-white areas deprived of physiological background pigmentation of lines reticular.
Hyperpigmented disorders
Confluent and reticulated papillomatosis [56,62]	Acquired, flat, asymptomatic, grey-brown scaly papules coalescing into larger patches arranged in a reticular fashion, commonly affecting the torso.	Subtle/small white scales and brownish clods separated by hypopigmented lines (cobblestone appearance, or gyri and sulci pattern).
Becker’s nevus [56,63]	Congenital, irregularly shaped hyperpigmented macule often accompanied by hypertrichosis, commonly affecting shoulder girdle or upper chest.	Poorly demarcated brown reticular or structureless areas and increased hair density.
Idiopathic eruptive macular hyperpigmentation [64,65]	Disseminated, nonconfluent, and asymptomatic pigmented macules affecting the trunk, neck, and proximal extremities, developing in childhood or adolescence without any background of inflammatory lesions or drug trigger.	Pigmented dots and clods distributed over the accentuated lines reticular (physiological pigmentation) with preservation of normally pigmented skin markings and follicular ostia.