When scars tell a story: cases of scar sarcoidosis preceding or following diagnosis of systemic disease

Sarcoidosis is a systemic granulomatous disease of unknown etiology, characterized by the formation of non-necrotizing granulomas in various organs, with the lungs and mediastinal lymph nodes being the most commonly affected sites. "Scar sarcoidosis" refers to the rare phenomenon in which sarcoid granulomas develop in pre-existing scars, such as surgical scars, tattoos, or sites of previous skin trauma. We report two cases of patients who presented with sarcoid granulomas developing in previous scar sites. The first case involved a 37-year-old man with a prior diagnosis of stage II pulmonary sarcoidosis who later developed erythematous plaques over scarred areas. A skin biopsy confirmed non-necrotizing granulomas. The second case describes a 45-year-old woman who presented with erythematous-violaceous plaques over previous traumatic scars, with subsequent tests revealing systemic sarcoidosis. Scar sarcoidosis highlights the diverse clinical presentations of sarcoidosis, emphasizing the need for clinicians to be vigilant of new or unusual manifestations. Recognizing this form of sarcoidosis can facilitate early systemic diagnosis and impact patient management. These cases underscore the importance of a multidisciplinary approach in diagnosing and managing sarcoidosis, given its dynamic and unpredictable nature.