Isolated Intramedullary Thoracic Spinal Sarcoidosis: A Case Report and Review of the Literature.

Sarcoidosis is a multisystemic inflammatory granulomatosis disease that rarely involves the central nervous system (CNS) and is even more so rarely isolated to the intramedullary thoracic spine. In isolated CNS sarcoidosis cases, surgical treatment is debated. We present here a case report and literature review on intramedullary thoracic spine sarcoidosis to evaluate potential portents of spine involvement and indications for surgical intervention. A 47-year-old female with a prior history of renal cell carcinoma presented with a week-long history of urinary retention and bilateral lower extremity numbness, and a 24-hour history of left lower extremity (LLE) weakness with saddle anesthesia. Magnetic resonance imaging demonstrated a syrinx spanning the spinal cord to the conus medullaris and a contrast-enhancing, expansile intramedullary thoracic lesion at T6-T7 with a non-enhancing, cystic right paraspinal lesion at T5. Given the patient's history of a kidney neoplasm, a metastatic work-up was completed. Biopsy of the T5 lesion was consistent with endometriosis. The patient underwent a T6-8 laminectomy with excisional biopsy and gross total resection of the intramedullary mass. Initial pathology was notable for lymphohistiocytic infiltrate with coagulative necrosis and rare multinucleated giant cells. At the one-month follow-up, the patient had improving LLE weakness and continued impairment of gait, balance, and coordination, but her symptoms of urinary retention, paresthesia, and numbness were resolved. Final pathology supported a diagnosis of sarcoidosis. At the three-month follow-up, the patient reported intermittent surgical site pain, but no other symptoms. She is followed up by her primary care consultant for symptom management and recurrence monitoring. Apart from the presented case, only one case of isolated intramedullary thoracic spine sarcoidosis was identified in the literature. The only case, of both review and presented, without significant symptom improvement did not undergo surgery. The available literature is limited; however, early surgical intervention may be indicated in isolated thoracic spine sarcoidosis.