Cervicothoracic intradural intramedullary deposition of calcium pyrophosphate dihydrate crystal: a tumor-mimicking lesion, case report and literature review

Abstract Background Calcium pyrophosphate deposition (CPPD) disease usually affects peripheral joints in older adults, whereas spinal involvement is rare and intramedullary cases have not been reported. We describe a unique case of intramedullary spinal pseudogout mimicking a tumor. Case presentation A 59-year-old woman presented with chronic cervicothoracic pain. MRI revealed an intramedullary lesion at C7–T2, initially suspected to be a low-grade glioma. Surgical biopsy, however, demonstrated calcium pyrophosphate crystal deposition, confirming CPPD. The patient’s postoperative course was uneventful, with symptomatic improvement under supportive therapy. A literature review identified four previously reported cervical intradural extramedullary CPPD cases (2006–2024), but no intramedullary lesions. Conclusions Intradural CPPD lesions are extremely rare, and this is the first reported intramedullary case. Crystal arthropathies should be considered in the differential diagnosis of spinal cord lesions resembling neoplasms. Further studies are required to better understand the pathophysiology, treatment, and prognosis of spinal pseudogout.