RESUMO Objetivo: Relatar um caso de histiocitose de células de Langerhans autolimitada e de início tardio. Descrição do caso: Paciente com 4 meses e meio de idade do sexo feminino, apresentando uma erupção cutânea eritematosa purpúrea, foi submetida a uma biópsia de pele, sendo diagnosticada com histiocitose de células de Langerhans cutânea isolada. As lesões regrediram em poucos meses e ela foi diagnosticada, retrospectivamente, com histiocitose de células de Langerhans autolimitada e de início tardio, após não apresentar nenhum envolvimento cutâneo ou sistêmico durante um seguimento de quatro anos. Comentários: A histiocitose de células de Langerhans autolimitada caracteriza-se pela proliferação clonal das células de Langerhans e apresenta-se com lesões cutâneas, sendo uma variante autolimitada rara de histiocitose. A doença só pode ser diagnosticada de forma retrospectiva, após o paciente não apresentar nenhum envolvimento sistêmico durante vários anos. Embora existam casos de manifestações ao nascimento ou durante o período neonatal, apenas alguns casos de histiocitose de células de Langerhans de idade tardia foram relatados. Lesões purpúreas que aparecem após o período neonatal podem sugerir histiocitose de células de Langerhans autolimitada e de início tardio. Uma vez confirmado o diagnóstico por biópsia cutânea, tais pacientes devem ser acompanhados regularmente, pois pode haver comprometimento sistêmico.

ABSTRACT Objective: To report a case of late-onset self-healing Langerhans cell histiocytosis. Case description: A 4½-month-old female patient presenting with an eythematopurpuric eruption underwent a skin biopsy for histopathology and was first diagnosed with isolated cutaneous Langerhans cell histiocytosis. Her lesions regressed within a few months and she was retrospectively diagnosed with late-onset self-healing Langerhans cell histiocytosis after being without skin or systemic involvement in a follow-up four years later. Comments: Self-healing Langerhans cell histiocytosis, which is characterized by clonal proliferation of Langerhans cells and presents with cutaneous lesions, is a rare self-limited variant of histiocytosis and can only be diagnosed retrospectively, after the patient remains free from systemic involvement for several years. Although it presents at birth or during the neonatal period, only a few cases of its late-onset type regarding the age of onset have been reported. Purpuric lesions that appear after the neonatal period serve as a clue for late-onset self-healing Langerhans cell histiocytosis and the patients should be monitored regularly for systemic involvement if the diagnosis is confirmed by a cutaneous biopsy.

Primary inoculation tuberculosis is an exogenous infection resulting from direct inoculation of bacteria into individuals with no acquired immunity to the organism. We report a 63-year-old male patient who was diagnosed with primary inoculation tuberculosis on the basis of clinical appearance and histopathological examination. The findings from this case emphasize the importance of clinical and histopathological findings in this rarely seen form of skin tuberculosis if the organism cannot be shown to grow in culture.