Angiotropic melanocytes: Possibly a distinctive finding in extra-facial acquired dermal melanocytosis

Background: Acquired dermal melanocytosis is a heterogenous group of hyperpigmented lesioins which predominantly involve the face. Aim: The aim of this study was to study the clinical presentation and histopathology of cases with extra-facial acquired dermal melanocytosis. Methods: Retrospective record analysis was performed between May 2016 to August 2019 to retrieve cases of extra-facial acquired dermal melanocytosis seen at the out-patient department of dermatology at the All India Institute of Medical Sciences, Jodhpur. Consecutive cases with histopathologically proven diagnosis of acquired dermal melanocytosis were included. Documentation of variation in clinical presentation and histopathologic findings was done in light of the existing literature. Results: Overall, four cases of extra-facial acquired dermal melanocyosis (female:male = 1:3) were seen during the study period. The lone case on head and neck involved the ear lobule and peri-auricular area. The other three cases had involvement of the hand. The histopathology confirmed the diagnosis of dermal melanocytosis but revealed peculiar findings of angiotropic melanocytes and dilated capillaries. Limitations: Small sample size and lack of comparison with perilesional normal skin were the limitations of this study. Conclusion: The findings of angiotropic melanocytes may be unique to extra-facial acquired dermal melanocytosis. This might indicate interaction between dermal melanocytes and capillary endothelial cells. This finding along with dermal capillary ectasia may indicate a possible role for vascular lasers in the management of these disorders

A Case of Acquired Dermal Melanocytosis Occurring on the Chest / 대한피부과학회지

Dermal melanocytosis, which is histologically characterized by the presence of dermal melanocytes, is most commonly found in Asians and other darkskinned people. It is observed in various congenital conditions such as the nevus of Ota, the nevus of Ito, the Mongolian spot and the blue nevus, and typically appears at birth or in early childhood. However, several cases that have appeared in adult life have been reported as acquired dermal melanocytosis. Herein, we report a unique case of acquired dermal melanocytosis diffusely affecting the left side of the chest of a 45-year old female. Additionally, a review of Korean literature regarding reported cases of unusual acquired dermal melanocytosis will be presented.

A Case of Acquired Dermal Melanocytosis showing the Manifestations of Bilateral Variant of Nevus of Ito / 대한피부과학회지

There are a number of pigmentation disorders due to dermal melanocytes, including Mongolian spot, nevus of Ota, nevus of Ito and blue nevus, which usually appear at birth or in early childhood. But, several types of acquired dermal melanocytosis which usually appear in adult have been reported. A 67-year-old woman presented with asymptomatic, multiple, symmetric, bluish macules on the upper back for 10 years. Histopathologic findings showed some scattered spindle-shaped cells containing melanin pigment in the upper dermis and these cells were positive for S-100 protein stain. We suggest this case may be an acquired and bilateral variant of nevus of Ito considering the relationship between the acquired bilateral nevus of Ota-like macules and nevus of Ota.

Two Cases of Acquired Dermal Melanocytosis / 대한피부과학회지

Dermal melanocytosis is observed in various congenital conditions including nevus of Ota, nevus of Ito and Mongolian spot. It usually appears at birth or in early childhood. Several types of acquired dermal melanocytosis which usually appear in adult life have been reported. As the late onset has been stressed, the term acquired is used. We report two cases of acquired dermal melanocytosis on the forearm and the back without any similar pigmentation elsewhere on the body. The first case is a 47-year-old man who had numerous grey-blue colored macules and patches on the upper back. Histopathologic findings showed a large number of spindle-shaped cells containing melanin granules in the dermis. On electron microscopy, dermal melanocytes with stage 3, 4 melanosomes and lipid droplet were observed. The second one is a 13-year-old girl who had a 3.8 X 2.5 cm sized dark grey colored patch on the left forearm. Histopathologic and EM finding were similar to case 1. We treated both cases with topical cream(retinoid and hydroquinone), but could not observe improvement. Their lesions have persisted without any change.