Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
Cobalt is an essential trace element utilised mainly in the form of vitamin B12 (cobalamin). Deficiency of cobalamin causes pernicious anaemia, but cobalt deficiency per se is virtually unknown in humans. Cobalt toxicity causes increased production of haemoglobin and can induce hypertriglyceridaemia and hypercholesterolemia.
Clinical application of chromium and cobalt measurement arises from the use of a chromium/cobalt/molybdenum (65/30/5) alloy in orthopaedic implants, especially hip replacements. Chromium and cobalt are released by friction on the metal-on-metal surfaces due to slight misalignment and can lead to failure of the implant. If uncorrected there can be severe local tissue damage with formation of a pseudo-tumour and necrosis of soft tissue. The MHRA has issued two warnings on these implants suggesting that the patient needs to be followed up for the life of the implant.
Specimen container paediatric:
Navy blue top ‘trace element’ tube with purple-striped label – preferred sample if sufficient blood can be collected
Pink top paediatric tube (EDTA anticoagulant)
Specimen container adult:
Navy blue top ‘trace element’ tube with purple-striped label (EDTA anticoagulant)
Available on request from Blood Sciences reception at both Freeman and RVI sites
Minimum volume paediatric:
1 mL blood
Minimum volume adult:
1 mL blood
Sample stability:
Whole blood samples are stable at 2-4°C for up to 6 weeks or at -20°C indefinitely.
Transport requirements:
Ambient temperature.
Freq analysis:
Assay performed weekly.
Quality assurance:
Trace Element Quality Assurance Scheme (TEQAS) for Trace Elements
Reference ranges:
| Comment | Cobalt (nmol/L) |
| Normal (without hip replacement) | <10 |
| MHRA limits (<7 ppb) | <120 |
Other info:
Assay performed by ICP-MS in standard mode.