Dermoscopy of eccrine angiomatous hamartoma: The spitzoid pattern

Abstract

Clinical presentation A 5-year old girl presented with an erythematous, asymptomatic nodule of the left knee, which appeared 1 year before (Fig 1). Fig 1 Clinical examination found an erythematous dome-shaped nodule of the left knee. Dermoscopic appearance Dermoscopic examination found a spitzoid pattern, with brown globules, a background of erythema, and a pseudo-reticular depigmentation around the globules (Fig 2). The lesion was excised to rule out a spitzoid melanoma. Fig 2 Dermoscopy shows a spitzoid pattern, with light to dark-brown globules, a background of milky-red erythema, and a pseudo-reticular depigmentation (inversed network) around the globules. Histologic diagnosis Histologic examination found in the reticular dermis an increased number of eccrine glands and terminal hair follicles admixed with irregular, dilated blood structures and fat lobules (Fig 3). Pathologic features were consistent with the diagnosis of eccrine angiomatous hamartoma (EAH). Key message EAH is a rare variety of hamartoma. EAH presents at birth or early childhood as a nonspecific red, brown, or yellow nodule or plaque. When symptomatic, EAH may be associated with hyperhidrosis or pain. 1 The diagnosis is established by histopathology. Recently, the first dermoscopic description of EAH was reported as the popcorn pattern, consisting of multiple yellow, confluent nodules in a popcorn shape, over a background of erythema and linear and arborizing blood vessels. 2 Here we report a typical case of EAH, with a spitzoid dermoscopic pattern. The presence of brown globules in dermoscopy is usually indicative of a melanocytic lesion, but in this case it is possible that the globules reflected the numerous dilated eccrine glands. The dermoscopic aspect of EAH is heterogeneous and can be misleading. More cases are needed to describe the dermoscopic landscape of EAH. Fig 3 The sections show increased numbers of eccrine glands and terminal hair follicles associated with abnormally dilated vessels (Hematoxylin-eosin saffron stain; original magnification per scale bar).