Dear Editor: Dyschromatosis universalis hereditaria (DUH) is a rare hereditary skin disorder that is characterized by a mixture of small and irregularly sized hyperpigmented and hypopigmented macules of a mottled or reticulated pattern. The usual onset age of DUH is 6 years1. The common pattern of inheritance is generally autosomal dominant; however, rarely, a few cases show a sporadic pattern. Some authors named this form as dyschromatosis universalis (DU) instead of DUH2. We report a case of DU in a 29-year-old female patient with no family history and a late onset of the disease. A 29-year-old Korean woman presented with asymptomatic multiple pinhead to rice sized mottled hypopigmented macules with diffuse hyperpigmented patches on the abdomen and left upper arm (Fig. 1A). The hyperpigmented lesions, which had been noted 1 year previously, started initially on the abdomen and gradually spread to the left upper arm. She has no history of systemic disease or any previous cutaneous disease. She also denied any family history of skin discoloration or similar skin lesions. Fig. 1 (A) Multiple pinhead to rice sized mottled hypopigmented macules with diffuse hyperpigmented patches. (B) A closer view. (C) A biopsy specimen taken from a hyperpigmented lesion on the abdomen showed increased abundant melanin pigments in the epidermis ... A biopsy specimen taken from the hyperpigmented lesion on the abdomen showed increased abundant melanin pigments in the epidermis, with normal number and distribution of melanocytes on hematoxylin-eosin, Fontana Masson, and MART-1 stainning (Fig. 1B). In contrast, the histopathologic finding of a hypopigmented macule suggested a reduced amount of melanin pigments in the lesion area (Fig. 1C). On the basis of these findings, the diagnosis was concluded to be DU. We recommended treatment with Q-switched Nd:YAG laser for the hyperpigmented lesions; however, she refused the therapy. She has been followed without any changes. Rycroft et al.3 reported a case with no family history, but was associated with short stature and high tone deafness. In addition, Shono amd Toda4 reported a case with no family history and associated with photosensitivity and a neurosensory hearing defect. Also, Kim et al.2 reported a case that occurred in the patient at age 20 years, with a sporadic pattern and with no comorbid conditions. Some authors suggest that DU is a more appropriate name for the sporadic cases rather than DUH2. DU should be differentiated from other conditions showing both hyperpigmentation and hypopigmentation, such as generalized Dowling-Degos disease, xeroderma pigmentosum, dyskeratosis congenita and chronic radiodermatitis. DU generally does not involve a family history and present only dyschromatosis without systemic disorder. Various therapeutic trials, such as psoralen and ultraviolet A irradiation, thin split-thickness skin autograft, and Q-switched ruby laser have been tried to treat these lesions; however, there is no definitely effective treatment for both hyperpigmented and hypopigmented lesions. Recently, Kim et al.5 reported that they successfully treated the hyperpigmented lesions of DUH with a Q-switched Nd:YAG laser. Only a few cases of DU have been reported worldwide, and we could find only three cases in the Korean literature (Table 1)2,3,4. Particularly, adult-onset DU like our case is very unusual. Thus, we here report a case of DU occurring in a 29-year-old female patient with no family history. Table 1 Reported cases of dyschromatosis universalis in global literatures (including Korea)