Abstract Crusted scabies or Norwegian scabies is a severe and highly contagious clinical variant of infestation by Sarcoptes scabiei, which can evolve exuberantly, coursing with diffuse erythroderma, which makes etiological diagnosis difficult, especially by non-dermatologists. Thus, the authors present a case report of erythroderma in a 65-year-old woman, who developed intense pruritus associated with erythroderma for about 2 weeks, with an associated fever peak. She had a previous clinical history of psoriasis and psoriatic arthritis, with long-term use of immunosuppressants and systemic corticosteroids. Evaluated by dermatologists who, through direct examination by skin scraping and skin biopsy, confirmed the diagnosis of crusted scabies. Based on this case report, the importance of differential diagnoses of erythroderma is highli-ghted, especially crusted scabies, a rare dermatosis that most often affects immunocompromised, frail, institutionalized patients or patients with precarious social conditions.

Resumo A escabiose crostosa ou sarna Norueguesa é uma variante clínica severa e altamente contagiosa da infestação pelo Sarcoptes scabiei, a qual pode evoluir exuberantemente cursando com eritrodermia difusa, o que dificulta o diagnóstico etiológi-co, principalmente por parte de médicos não-dermatologistas. Dessa forma, os autores apresentam um relato de um caso de eritrodermia em uma mulher de 65 anos, evoluindo com quadro de prurido intenso associado à eritrodermia, há cerca de 2 semanas, com pico febril associado. Apresentava história clínica pregressa de psoríase e artrite psoriásica, com uso de imunossupressores e corticoides sistémicos por longo prazo. Avaliada por dermatologistas que, por meio de exame direto por raspado cutâneo e biópsia de pele, confirmaram diagnóstico de escabiose crostosa. A partir do caso reportado, ressalta-se a importância dos diagnósticos diferenciais da eritrodermia, sobretudo a escabiose crostosa, uma dermatose rara, que afeta mais frequentemente doentes imunodeprimidos, com fragilidade, institucionalizados ou com condições sociais precárias.

ABSTRACT Syphilis is a chronic bacterial sexually transmitted infectious disease caused by Treponema pallidum. Different age groups are affected by heterogeneous clinical forms of the disease. We report a case of atypical secondary syphilis in an elderly patient with diffuse annular erythematous lesions on the chest, back, upper and lower limbs diagnosed by histopathological, immunohistochemical and serological tests.

Abstract Langerhans cell histiocytosis is a rare clonal proliferative disease, characterized by the infiltration of one or multiple organs by histiocytes. Due to the diversity of signs and symptoms, the diagnosis of this disease is often late. The estimated incidence in adults is one to two cases per million, but the disease is probably underdiagnosed in this population. This report presents a case of disseminated Langerhans cell histiocytosis. The authors highlight the most characteristic aspects of this rare and heterogeneous disease, which usually presents as a challenging clinical diagnosis.

Nevo agminado é um conjunto de lesões melanocíticas confinadas a uma área do corpo. Existem muitas lesões descritas na literatura como agminada s, como nevos azuis, lentigos múltiplos, nevo de Spitz, mas existem poucos casos de nevos melanocíticos agminados congênitos descritos. Relatamos o caso de um paciente do sexo masculino que se apresentou com um nevo agminado congênito, enfatizando a importância do exame físico, dermatoscopia, avaliação histológica, diagnóstico diferencial e seguimento para descartar a possibilidade de alterações displásicas ou malignas.

Agminated nevus is a cluster group of melanocytic nevi confined to a localized area of the body. There are many pigmented lesions described in the literature as agminated, such as blue nevi, multiple lentigines and Spitz nevi, but only a few cases of congenital agminated melanocytic nevi have been described. We report a case of a male child who presented with congenital agminated nevi, emphasizing the importance of physical examination, dermoscopy, histopathological evaluation, differential diagnosis and follow up to rule out the possibility of dysplastic or malignant changes.

Líquen nítido é uma dermatose rara, caracterizada por pápulas arredondadas normocrômicas de diâmetro, variando entre 1-2 mm, e geralmente assintomáticas. Sem predileção por sexo ou raça, acomete, principalmente, crianças e adultos jovens, na maioria dos casos, possuindo curso clínico imprevisível e tendendo à regressão espontânea, anos após o início da doença. As lesões são em geral localizadas, mas raros relatos da doença cursando com lesões disseminadas existem.

Lichen nitidus is a rare dermatosis, characterized by round, skin-colored papules whose size varies between 1-2 mm and are generally asymptomatic. It does not have predilection for gender or race, affecting mainly children and young adults. Its clinical course is unpredictable, but most cases tend to spontaneously regress years after the onset of the disease. Lesions are often localized, but rare reports of disseminated disease exist.