Aplicação da dermatoscopia no auxílio diagnóstico da ocronose exógena

Abstract

Exogenous ochronosis consists of chronic hyperpigmentation of areas previously treated with topical agents such as hydroquinone, resorcinol, antimalarials and phenol. Early diagnosis allows to promptly suspend the causative agent and it is imperative since the available therapeutic options are scarce and have presented so far unsatisfactory results. Three cases of exogenous ochronosis on the face which were diagnosed with the use of dermoscopy are presented. Dermatoscopy showed blackish-gray amorphous structures, some obliterating the follicular openings. Histopathological examination confirmed the diagnosis. Keywords: Dermoscopy; Ochronosis; Pigmentation disorders Resumo: A ocronose exógena consiste em hiperpigmentação crônica de áreas previamente tratadas com agentes tópicos como: a hidroquinona, a resorcina, os antimaláricos e o fenol. O diagnóstico precoce permite suspender prontamente o agente causador, uma vez que as opções terapêuticas disponíveis são escassas e com resultados insatisfatórios. Reportam-se três casos de ocronose exógena na face, diagnosticados pela dermatoscopia. O estudo dermatoscópico evidenciou estruturas amorfas de coloração cinza-enegrecido, algumas obliterando as aberturas foliculares. O exame histopatológico corroborou o diagnóstico.

Exogenous Ochronosis

“…[ 43 ] and Sandra et al . [ 44 ] demonstrated in dermoscopy of patients with EO, dark brown globules and globular-like structures on a diffuse brown background. In contrast, in patients with melasma a fine brown reticular pattern on a background of a faint light brown, structure-less area was noted.…”

Alkaptonuria - Case report

“…6 The description of dermoscopy in endogenous ochronosis was not found in any of these articles; however, the description of dermoscopy of a lesion by exogenous ochronosis, in which it is possible to visualize blackened blue dots obstructing hair follicles was observed in an article. 7 …”

Argyria mimicking a blue nevis: dermoscopy features

“…Importantly, the use of dermoscopy enabled the observation of annular structures in lentigo solaris, malignant lentigo and ochronosis. 6 In contrast to these lesions, the pigment deposition in argyria surrounds the eccrine glands rather than the follicle openings. Furthermore, the clinical manifestations of other skin disorders present additional dermoscopy structures that can serve to differentiate these lesions from those associated with localized argyria.…”