Written By: Osheen Abnous, Maria Vardapetyan, Eric Baghdasaryan

Copper is an essential element to all organisms, and it is a contributor in several enzymes vital to the function of hematopoietic, vascular, and skeletal tissues, as well as the structure and function of the nervous system. 

As a crucial metal, copper plays an important role in chemical reactions throughout the human body; this includes the central nervous system. Enzymes are substances that facilitate chemical reactions. There are many copper-dependent reactions in the human body.  In humans, the major site of absorption of dietary copper is still unclear.  Copper in humans is absorbed in the proximal small bowel, duodenum, and ileum. This is after it has passed the acidic environment of the stomach.

Copper deficiency can be caused by malnutrition, prematurity, parenteral or enteral feeding without copper supplementation, gastrectomy, and excessive zinc therapy. The common causes of copper deficiency have been zinc supplementation,  and changes to the PH (acidity) of the stomach. This can be the result of the alteration of the stomach anatomy, and by chronic acid suppression by proton pump inhibitors (antacids), and similar medications. Physicians need to be alert with patients who show signs of copper deficiency or are at a high risk of developing a copper deficiency. 

It is important to raise greater awareness about copper deficiency because there is a growing number of patients undergoing surgeries for obesity, as the occurrence of copper deficiency will increase in the future. 

Studies of patients who have had weight loss surgery in the past experience common symptoms such as pain involving the feet, gait abnormality (unusual walking), lower limb weakness, and recurrent falls. Common lab results include unusually low serum copper and serum ceruloplasmin levels. In some cases, elevated zinc levels are also present. Treatment includes cupric sulfate infusion until normal copper levels are reached, which then need to be maintained for the future. Vitamin B-12 deficiency has also been reported as a possible cause of myelopathy, which is a nervous system disorder that affects the spinal cord. As stated earlier, neurological damages are often irreversible and cause permanent damage to patients. Early diagnosis from physicians is crucial for patients who have undergone gastric bypass surgery, and the sooner they are diagnosed, the less permanent damage the patient will endure.

Case Discussions:

A 49-year-old woman had gastric bypass surgery for obesity 24 years age. She presetend with increasing lower limb stiffness and numbness. Additionally she reported tingling of the feet. As her pain continued to increase, she began using a walker, and her symptoms continued to worsen. After undergoing a neurological examination, results showed that the patient had increased lower limb tone and an absent perception of vibration at the toes and ankles. Laboratory results showed that the patient had copper levels barely detectable. This included serum copper and serum ceruloplasmin levels. In addition, the patient had reduced serum carotene (vitamin A) levels. 

The patient received cupric sulfate intravenously daily through an 8-week period. After each daily infusion of cupric sulfate, the patient reported to have slight decreases in numbness and an increased tingling sensation. After the 8-week period, lab results showed that serum copper levels were normal and are needed to be maintained. Her night blindness was corrected by vitamin A injections.

In another case, a 53-year-old woman had symptoms of abnormal gait (abnormal walking) and anemia (lack of healthy red blood cells), and was seen for evaluation. The patient complained of pain in the lower legs, which would worsen over time and move up towards her thighs. As her ability to walk continued to worsen, the patient resorted to using a wheelchair. Her medical history consisted of an RYGB surgery for obesity. The only significant supplementation she received was 1000 μg vitamin B12 subcutaneously for several years. She had absent positional and vibratory sensation in the lower extremities to the knee. In addition, touch sensation was decreased. Laboratory examination revealed an elevated serum zinc level, and extremely low serum copper and ceruloplasmin levels.  

For treatment, the patient received intravenous copper over a 6-day period, was discharged home, and then received weekly intravenous copper infusions thereafter. After a month of receiving intravenous copper, serum copper levels returned to normal. In addition, the patient’s pain in the lower leg improved, but vibratory sensation remained absent in the same area. Four months after being discharged from the hospital, the patient began walking with a cane.