Dermoscopy of Lichen Aureus.

Abstract

Case Report A 32-year-old male (Fitzpatrick skin type 2) presented with asymptomatic multiple golden-brown colored plaques over bilateral lower legs. Patient's job entails prolonged standing as he is a vegetable vendor by occupation. On examination, both lower legs had multiple golden-brown plaques of variable size with few satellite lesions in its vicinity, predominantly around the ankles. There was no pedal edema or regional lymphadenopathy [Figure 1a and b]. Dermoscopy of the lesions was done by Universal Serial Bus (USB), non-contact dermatoscope [Dinolite AMZT 73915, Edge 3, Taiwan]. On polarizing mode, it showed orange-brown background with few showing central blue-gray dots and granules. We also appreciated an increase in pigmentary network with complete as well as few broken brown rings along with red dots/globules (50×) [Figure 2a]. On high power (170×), the presence of linear as well as twisted vessels were also appreciated [Figure 2b and c]. Histopathology showed evidence of perivascular lymphocytic infiltration, endothelial swelling, hemosiderin deposition, and erythrocyte extravasation in the upper dermis suggestive of capillaritis with basal cell vacuolization, which confirmed the diagnosis of lichen aureus [Figure 3a and b]. Patient was advised leg elevation at night and to avoid prolonged standing. He was prescribed topical steroid of moderate potency and capsule calcium dobesilate 500 mg twice a day and he showed considerable improvement within 6 weeks of follow-up.Figure 1: (a and b): Clinical picture showing multiple golden brown macules over bilateral lower legsFigure 2: (a) Dermoscopic findings at ×50 magnification (polarizing mode) showing increased pigmentary network with few broken rings (yellow arrow) and red globules (blue arrow). (b) Dermoscopic findings at ×170 magnification (polarizing mode) showing central orange-brown background (red arrow) with blue-gray dots and granules (purple arrow) and linear (orange arrow) and twisted capillaries (green arrow). (c) Dermoscopic findings at ×170 magnification (polarizing mode) showing similar features along with red dots (blue arrow). (USB Dermatoscope, Dinolite AMZT 73915, Edge 3)Figure 3: (a) Histopathology (×10, Hematoxylin and Eosin stain) showing perivascular infiltration, endothelial swelling, and erythrocytic extravasation suggestive of capillaritis with hemosiderin deposition. (b) Histopathology (×40, Hematoxylin and Eosin stain) showing similar features along with basal cell degenerationPigmented purpuric dermatoses is a group of disorders characterized by multiple coppery brown macules and plaques over bilateral lower legs.[1] Lichen aureus, also known as “lichen purpuricus” is one of the less common variants of pigmented purpuric dermatoses, which presents with golden rust, bronze to brown colored macules, papules, and plaques, mostly over lower legs.[2] Dermoscopy of lichen aureus has been reported in only two reports so far to the best of our knowledge. Zaballos et al. reported dermoscopic features in three cases of lichen aureus showing brownish or coppery-red diffuse coloration of the background, red dots, globules, and a network of brownish to gray interconnected lines.[3] Portela et al. reported coppery-red pigmentation in the background, permeated by dark brown network with linear vessels in the central portion of the lesion along with punctate vessels, especially in the periphery of the lesion.[34] Histopathology shows band-like lymphocytic infiltrates and basal cell vacuolization. Lymphocytic infiltration is seen around vessels of superficial plexus with extravasated erythrocytes and hemosiderin deposition in histiocytes.[5] The dilated blood capillaries and erythrocytic extravasation can be seen as red points and globules, while increased coppery red pigmentation is seen due to hemosiderin deposition or basal layer hyperpigmentation represented by pigmented network lines.[34] Brownish diffuse coloration, red dots/globules and network of brownish to gray interconnected lines with linear vessels have also been observed in vasculitic lesions; however, on clinical evaluation, vasculitis was highly unlikely.[6] In addition to these described features, our case showed additional blue-gray dots and granules over an orange brown background, which is considered as a consistent dermoscopic feature of most of the lichenoid disorders. This lichenoid pathology was appreciated on histopathological evaluation as well. Linear and twisted vessels were also appreciated which could be a result of capillaritis. We present dermoscopic analysis of a case of lichen aureus and believe that this tool can contribute toward a faster diagnosis and prompt management. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.