A Case of Pseudogout Causing Thoracic Myelopathy.

Calcium pyrophosphate deposition disease is not an uncommon cause of polyarthritis, especially in the elderly. This disease typically affects the appendicular skeleton but may rarely affect the axial skeleton as well. When the axial skeleton is involved, it can lead to numerous neurological signs and can be disabling. We describe a case in which a 68-year-old male presented with on-and-off myelopathy and was thought to have chronic inflammatory demyelinating polyneuropathy. Magnetic resonance imaging of the spine suggested an inflammatory or infectious lesion at the thoracic level. However, after a surgical biopsy, pathologists concluded that calcium pyrophosphate deposition, or pseudogout, was the cause of this patient's neurological symptoms. Pseudogout in the spine, especially the thoracic spine, is exceptionally rare. There are very few additional cases reported. In this report, we review the current literature on existing similar cases, radiological findings, risk factors, and treatments for this condition in hopes of increasing knowledge and awareness of this rare differential.