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Nocardia is a genus of gram-positive, filamentous, aerobic bacteria that belongs to the Actinomycetales order. With over 50 species, it is ubiquitous in dust, soil, decaying organic matter, and stagnant water. Inhalation of the pathogen often leads to pulmonary nocardiosis, while extrapulmonary nocardiosis can affect the central nervous system, skin, and subcutaneous tissues. Primary cutaneous nocardiosis occurs when the pathogen is introduced through a skin lesion or insect bite, for example, this report presents a case of primary cutaneous nocardiosis in a patient with Minimal Change Glomerulonephritis and iatrogenic immunosuppression. Magnetic resonance imaging revealed extensive involvement of the skin, subcutaneous tissue, and lower limb muscles.

Metastasis to bone is a common occurrence among epithelial tumors, with a high incidence rate in the Western world. As a result, bone lesions are a significant burden on the healthcare system, with a high morbidity index. These injuries are often symptomatic and can lead to functional limitations, which in turn cause reduced mobility in patients. Additionally, they can lead to secondary complications such as pathological fractures, spinal cord compression, hypercalcemia, or bone marrow suppression. The treatment of bone metastases requires collaboration between multiple healthcare professionals, including oncologists, orthopedists, neurosurgeons, physiatrists, and radiotherapists. The primary objective of this study is to evaluate the correlation between two methods used to assess local control. Specifically, the study aims to determine if a reduction in the volume of bone lesions corresponds to better symptomatic control in the clinical management of patients, and vice versa. To achieve this objective, the study evaluates morphological criteria by comparing pre- and post-radiotherapy treatment imaging using MRI and RECIST 1.1 criteria. MRI without contrast is the preferred diagnostic imaging method, due to its excellent tolerance by patients, the absence of exposure to ionizing radiation, and the avoidance of paramagnetic contrast media side effects. This imaging modality allows for accurate assessment of bone lesions. One of the secondary objectives of this study is to identify potentially useful parameters that can distinguish patients into two classes: “good” and “poor” responders to treatment, as reported by previous studies in the literature. These parameters can be evaluated from the imaging examinations by analyzing morphological changes and radiomic features on different sequences, such as T1, STIR (short tau inversion recovery), and DWI-MRI (diffusion-weighted).