Objective:
To describe an unusual case of symptomatic copper deficiency initially suspected to be paraneoplastic syndrome.
Background:
Copper deficiency is exceedingly rare, especially in developed nations, and is usually the result of genetic deficit. It often presents with neuropathy, weakness and encephalopathy. In this case, we describe a case of copper deficiency presenting with weakness, hallucinations and encephalopathy initially mistaken for paraneoplastic syndrome in a patient recently diagnosed with breast cancer.
Results:
Our patient is a 58 year old female with a history of recently diagnosed breast cancer who presented with new-onset lower extremity weakness and confusion. She was initially admitted to the medical-oncology service for management of her malignancy. During her hospitalization, she developed frank hallucinations and worsening encephalopathy. Neurologic workup including MRI brain, C and T-Spine, EEG, lumbar puncture with basic studies and autoimmune panel were negative. She got 3 days of IVIG and 5 days of PLEX with no improvement. The patient’s sister revealed for 8 weeks she had only been eating vegetables grown in her own garden. EMG revealed axonal sensorimotor neuropathy. Serum vitamins were checked and revealed a copper level of 30 ug/dL (80-120 ug/dL). She was started on IV copper replacement and slowly improved; she was seen in the clinic six months later with marked improvement of her mentation, but persistent lower extremity paraparesis.
Conclusions:
While vitamin deficiency—especially copper deficiency—is rare, it should be considered in cases where patients with weakness and neuropsychiatric symptoms have a benign neurologic workup and fail to respond to conventional immunologic therapies.