Nevus Vascularis Mixtus / 대한피부과학회지

The concept of mosaicism has been used to explain different cutaneous patterns, such as the lines of Blaschko, the checkerboard pattern, the phylloid pattern, and a patchy pattern. Many mosaic patterns are caused by loss of heterozygosity, the genetic mechanism by which a heterozygous somatic cell becomes either homozygous or hemizygous. A particular form of loss of heterozygosity is twin spotting, which give rise to two contrary homozygous daughter cells. The concept of twin spotting has been used for some of these human phenotypes, which are characterized by the co-occurrence of two different nevi, including nevus vascularis mixtus. Nevus vascularis mixtus is a rare vascular malformation characterized by the coexistence of a nevus anemicus and a nevus telangiectaticus, and can be associated with extra-cutaneous anomalies, such as cerebral malformations. Herein, we report a 6-year-old girl with paired cutaneous vascular nevi telangiectaticus, anemicus, and nevus vascularis mixtus, that were distributed on the left side of her chest and left arm, without other systemic and neurologic anomalies.

An Acquired Anemic Patch Developed after a Cyst Excision: Is It a Variant of Nevus Anemicus?

A 53-year-old male presented with a 6-year duration of a child's-palm sized hypopigmented patch located on his neck. He had a history of surgical excision of an epidermal cyst on the neck, and the hypopigmented patch developed about one month after the excision next to the surgery site. Application of cold or heat did not make the lesion distinct from the surrounding skin. Pressure on the lesion by a glass slide made the lesion indistinguishable from surrounding uninvolved lesions. Giving friction to the lesion failed to induce erythematous change, making it clearly visible. Histologically, the lesion showed normal findings with adequate numbers of melanocytes in the basal layer. Herein, we present an interesting case of an acquired anemic patch which developed after a cyst excision. We postulate that nerve damage after surgery that regulates the vascular tone of cutaneous vessels may have been an inducing event of the anemic patch in this patient.

Clinical Study of Nevus Anemicus / 대한피부과학회지

Nevus anemicus is a congenital anomaly characterized by pale macules of varying size and shape, and it is due to the increased sensitivity of blood vessels to catecholamines. However, the clinical features of nevus anemicus are not yet fully established. A clinical observation was made analyzing 26 cases of nevus anemicus over a 10-year period. Histopathological investigation in 6 cases, stain with Fontana-Masson in 4 cases, irradiation of ultraviolet B in 5 cases, digital infrared thermal imaging in 5 cases and color analysis using true-color imaging in 12 cases were also performed. The results were as follows: 1. The ratio of men to women was 1.2:1. The lesions were mostly(80%) present before the age of 18, but only 15% of the patients' lesions were present at birth. 2. The lesions were most frequently found on the face(33.3%) and neck(33.3%), followed by the chest(14.8%), lower extremities(7.4%) and back(7.4%). 3. Most patients(92.3%) had a single lesion. The extent of the lesions did not exceed 10% of the body surface area and the lesions did not show any progression or resolution. 4. The stainability of Fontana-Masson in nevus anemicus lesions showed no significant change compared with perilesional normal skin. 5. Irradiation of ultraviolet B ray(minimal erythemal dose to 80mJ/cm2) did not induce erythema on nevus anemicus lesions. 6. There was no significant temperature difference between nevus anemicus lesions and perilesional normal skin. 7. There was no significant correlation between chrominance and age. In conclusion, nevus anemicus in Korea shows the same incidence in both sexes, it usually arises at birth or childhood, but it may also develop later in life. Most patients show focal lesions that do not progress or resolve.

Phakomatosis Pigmentovascularis

Phakomatosis pigmentovascularis was first described in 1947 as a distinctive association of cutaneous hemangioma and pigmentary nevi by Ota et al. We describe a 7-year-old boy who, since birth, had three kinds of discolored patches over the various parts of the body: blue spots (dermal melanocytic nevi), reticulated reddish patches (nevus flammeus), and hypopigmented macules (nevus anemicus). No systemic disease was found.