Around 50 mycobacteria species cause human disease. Immunosuppressive states predispose to non-tuberculous mycobaterium infection, such as Mycobacterium chelonae: AFB, non-tuberculous, fast growth of low virulence and uncommon as a human pathogen. It may compromise the skin and soft tissues, lungs, lymph nodes and there is also a disseminated presentation. The diagnosis involves AFB identification and culture on Agar and Lowenstein-Jensen medium base. A 41-year-old female with MCTD (LES predominance) is reported, presenting painless nodules in the right forearm. She denied local trauma. Immunosuppressed with prednisone and cyclophosphamide for 24 months. Lesion biopsy has demonstrated positive bacilloscopy (Ziehl-Neelsen stain) and M.chelonae in culture (Lowenstein-Jensen medium base), therefore clarithromycin treatment has been started (best therapy choice in the literature).

O lúpus eritematoso crônico discoide linear é manifestação rara da doença lúpica cutânea, em que lesões eritêmato-atrófico-discrômicas dispõem-se nas linhas de Blaschko. Descrevemos o caso de um menino de 15 anos, com dois anos de história de lesões discoides eritêmato-atróficas, hipo e hiperpigmentadas, dispostas nas linhas de Blaschko do membro superior direito. O exame histopatológico revelou atrofia da epiderme, hiperqueratose, rolhas córneas, espessamento da zona da membrana basal, infiltrado inflamatório crônico perianexial e perivascular superficial e profundo, depósito de mucina na derme, confirmando o diagnóstico. Há, no total, 14 casos descritos dessa variante que se inicia frequentemente na infância e que não apresenta predomínio quanto ao sexo. As lesões ocorrem preferencialmente na face. Não há relatos de associação com doença sistêmica

Linear chronic discoid lupus erythematosus is a rare manifestation of cutaneous lupus in which erythematous, atrophic, dyschromic lesions are located along the lines of Blaschko. This report describes the case of a 15-year old boy with a 2-year history of discoid, erythematous, hyper and hypopigmented lesions with central atrophy, situated along the lines of Blaschko on his right arm. Histopathology showed epidermal atrophy, hyperkeratosis, follicular plugging, thickening of the basement membrane zone, and superficial and deep chronic perivascular and periadnexal inflammatory infiltrate, with dermal mucin deposit, thus confirming diagnosis. A total of 14 cases have been described of this variant, the onset of which is often in childhood. There is no difference in incidence between genders. Lesions most commonly develop on the face. There have been no reports of any association with systemic disease