Abstract Introduction Sarcoidosis is a multi-system granulomatous disease that involves the lungs in most cases. Common sites of extra-pulmonary involvement include the skin, lymph nodes, eyes and liver. Identifying all affected systems is crucial as organ involvement drives therapeutic decisions. Diagnosis requires the presence of non-necrotizing granulomas without alternative explanation, ideally from the most easily accessible tissue site. Here, we present a case of unrecognized subcutaneous sarcoidosis. Case Summary A 61-year-old man with tobacco use disorder in remission presented for two years of chronic dry cough and dyspnea. Computed tomography of the chest showed mild paraseptal emphysema, calcified and noncalcified mediastinal and hilar lymphadenopathy and bilateral calcified lung nodules. At this visit numerous subcutaneous nodules of his upper extremities were noted. Testing for endemic mycoses was negative. Endobronchial ultrasound (EBUS) guided biopsy of mediastinal lymph nodes revealed non-necrotizing granulomas, and he was diagnosed with sarcoidosis. Following a care transition to our medical system, his physical examination revealed numerous firm, mobile, non-tender, bilateral subcutaneous nodules consistent with subcutaneous sarcoidosis. He reported the development of many new nodules on his arms and thighs 18 months ago, but that a large one on his right arm had been present for nearly 30 years. Ultimately, he was diagnosed with sarcoidosis with pulmonary and subcutaneous involvement and started immunomodulatory therapy due to active subcutaneous sarcoidosis. Discussion Subcutaneous sarcoidosis, also known as Darier-Roussy sarcoidosis, is a rare manifestation of sarcoidosis occurring in an estimated 1.4 to 6% of individuals. It presents as firm, subcutaneous nodules without changes to the overlying epidermis. Most often the nodules occur on the upper and lower extremities in patients in their 5th or 6th decade of life. This case highlights the importance of recognizing rare, non-pulmonary manifestations of sarcoidosis as these have implications for both diagnosis and treatment. It is possible that a diagnosis could have been made via subcutaneous biopsy as opposed to invasive testing with EBUS, which would have entailed less risk. Furthermore, the presence of a subcutaneous lesion for nearly 30 years in combination with his degree of calcification on computed tomography suggests his disease was longstanding and highlights the opportunity for more prompt diagnosis with recognition of his subcutaneous manifestation. Last, subcutaneous sarcoidosis is associated with increased risk of systemic disease, but less pulmonary involvement. This makes the diagnosis more challenging while also highlighting the need for prompt identification and management of extra-pulmonary systemic involvement. This abstract is funded by: N/a
Bawmann et al. (Fri,) studied this question.