Key facts
- A woman developed severe neurological, cardiac, and thyroid symptoms attributed to cobalt poisoning.
- The poisoning was linked to a hip replacement revision surgery involving a cobalt-chromium alloy component.
- Doctors found metallic fluid and discolored tissue around the patient's hip joint during a second surgery.
- Blood tests revealed cobalt levels 59 times higher than normal and chromium levels over 300 times higher than normal.
- The patient underwent a second revision surgery and began chelation therapy for cobalt removal.
A 56-year-old woman was admitted to the hospital with a severe and worsening array of symptoms, including a progressive "pins and needles" sensation in her extremities, difficulty walking, short-term memory problems, concentration issues, irritability, loss of appetite, and heart palpitations. Her medical history included high blood pressure, anxiety, depression, hypothyroidism, and a previous hip replacement from 20 years prior.
Doctors noted that four weeks before her current symptoms began, her thyroid medication dosage was increased. However, they initially attributed her neurological symptoms to potential nerve damage from a recent hip revision surgery, though this did not fully explain the bilateral nature of her symptoms or her other health issues. Thorough examinations revealed tachycardia and reduced sensitivity to touch in all four limbs. Blood work showed elevated hemoglobin levels, and an X-ray of her hip indicated deposits around the artificial joint.
Upon receiving records from her hip revision surgery, which occurred three months prior, doctors learned that the original titanium and ceramic hip joint had failed, causing the ceramic liner to shatter. During the revision, the ceramic liner was replaced with polyethylene, and the ceramic femoral head was replaced with a cobalt-chromium alloy. The original titanium components were retained. Doctors immediately diagnosed severe cobalt poisoning, which aligned with her neurological, cardiac, and thyroid dysfunction, as well as her elevated hemoglobin levels due to cobalt's effect on hypoxia-induced factor.
The rapid progression of her toxicity led doctors to speculate that residual ceramic microparticles from the shattered liner may have caused excessive wear on the new cobalt-chromium head, releasing cobalt into her bloodstream. A second hip revision surgery confirmed this, revealing a pool of grey, metallic fluid and necrotic, silver-gray stained tissues around the joint. Surgeons cleaned the area, replaced the cobalt-chromium head with a ceramic one, and initiated chelation therapy. Pre-surgery blood tests showed cobalt levels at 592 ng/mL (normal <10 ng/mL) and chromium levels at 62.4 ng/mL (normal <0.2 ng/mL). Her recovery was described as slow and non-linear.