Agminated melanocytic nevus status post dabrafenib therapy for metastatic melanoma.

Agminated melanocytic nevus is an uncommon type of mole, characterized by a local group of macular or papular pigmented lesions, well demarcated, without a common pigmented background. This pattern has also been associated with Spitz nevi, dysplastic melanocytic nevi, and non-melanocytic lesions.We describe the onset of an acquired agminated melanocytic nevus after dabrafenib treatment. Our case highlights paradoxical MAPK activation in the setting of single-agent BRAF blockade and underscores the importance of characterizing the diverse side effects of selective BRAF inhibitors. This is the first case, to our knowledge, of agminated melanocytic nevus in association with dabrafenib.

Livedo Racemosa, Reticulated Ulcerations, Panniculitis and Violaceous Plaques in a 46-year-old Woman.

Clinically amyopathic dermatomyositis (CADM) is a subset of dermatomyositis (DM) that has conventional cutaneous manifestations of DM, but paradoxically, little or no muscle involvement. In 2005, a novel antibody was described in association with CADM - anti-melanoma differentiation-associated gene 5 (anti-MDA5). Patients with this serologic marker have a characteristic mucocutaneous phenotype consisting of skin ulceration among other signs. We describe the case of a 46-year-old woman with CADM, elevated anti-MDA5 autoantibodies, and unusual clinical features (livedo racemosa, florid acral edema) among the classical phenotype of MDA5 DM (arthralgias, ulcerations, panniculitis) and classical DM lesions (Gottron papules, heliotrope rash). The patients did not develop interstitial lung disease or internal malignancies and experienced a rapid response to prednisolone and intravenous immunoglobulins. After 2 years, she has no relapse of her cutaneous disease and continues 5 mg prednisolone and 2 g/kg kilogram of intravenous immunoglobulin every 3 months for maintenance. Our case highlights the clinical heterogeneity of CADM and underscores the importance of a comprehensive approach to DM patients. It was previously postulated that anti-MDA5 antibody could target vascular cells and compromise vascular function, the presence of livedo racemosa lesions, and MDA5 antibodies in a patient with negative thrombophilia workup, reinforce this idea. This is the first case, to our knowledge, of CADM with acral panniculitis and livedo racemosa.