Not All Ascending Weakness and Numbness Is Guillain-Barré Syndrome: A Report of Two Cases of Copper Deficiency Myelopathy.

Copper deficiency can lead to progressive neurological dysfunction, but its symptoms may overlap with other myeloneuropathies, making diagnosis challenging. Clinical features are often nonspecific presentations that may result in initial consideration of alternative neurologic conditions. We present two cases in which copper deficiency was identified after an evolving clinical picture. The first is a 70-year-old woman with a history of esophageal and breast cancer, complicated by esophagectomy and jejunostomy tube feeding, who developed six months of progressive ascending sensory loss and gait instability. The second is an 85-year-old woman with chronic zinc supplementation and denture adhesive use, presenting with two weeks of ascending paresthesias and imbalance. These cases highlight the importance of considering nutritional and surgical history in the evaluation of progressive myeloneuropathy, as well as key physical examination, laboratory, and imaging findings. Clinicians should maintain a high index of suspicion for copper deficiency in patients presenting with Guillain-Barré syndrome (GBS)-like symptoms, particularly those with risk factors for malabsorption or chronic zinc exposure.