Hypopigmentary diseases other than vitiligo are common. But, their relative prevalence was not studied so far.

Our purpose was to show clinical features of hypopigmentary diseases except vitiligo tohelp clinicians differentiate hypopigmentary diseases.

Each disease was diagnosed by the dermatologists on the basis of clinical features, Wood's lamp examination or histopathologic examination. Vitiligo was excluded by the same methods.

In 301 patients, nevus depigmentosus was the most common, followed by pityriasis alba, pityriasis versicolor, postinflammatory hypopigmentation, idiopathic guttate hypomelanosis in descending order of frequency. Male preponderance was observed in other diseases except nevus depigmentosus. Nevus depigmentosus, postinflammatory hypopigmentation, pityriasis alba, and pityriasis versicolor were common in the 1st and 2nd decades. Idiopathic guttate hypomelanosis was observed mostly in the elderly. Most nevus depigmentosus had one lesion. Pityriasis alba and postinflammatory hypopigmentation most commonly had 2 to 5 lesions.In pityriasis versicolor and idiopathic guttate hypomelanosis, more than 20 lesions were most common. Trunk was the most common site in nevus depigmentosus and pityriasis versicolor, the face in pityriasis alba and extremities in idiopathic guttate hypomelanosis. Postinflammatory hypopigmentation had no predilection sites.

In this study, we showed differences in clinical features of several hypopigmentary disorders.