Chromium (blood)

Alternative names, keywords

Cr, metal on metal, MoM

Samples required

EDTA blood (purple cap/ yellow cap ring, 4 mL tube).*

Collect two samples and send the second for cobalt and chromium testing. The first drawn sample is used to wash out any potentially contaminating traces of metals from the steel needle and can be used for other assays (e.g. FBC).
Chromium and cobalt can both be done on the same sample, but due to the risk of metal contamination the sample cannot be shared with any other tests.

* if querying deficiency or toxicity from other cause than MoM hip replacement, please send a second-drawn clotted blood for serum chromium:

Clotted blood (red cap NO SEPARATOR GEL, 6 mL tube). Smaller tubes are available for paediatric samples. Please contact Biochemistry for gel-free red-top clotted tubes if there are no supplies in your area.

Test indications

Investigation of metal-on-metal hip replacements.

Reference range

In MoM hip replacement,  MDA/2017/018 action limit post-implant is >134.5 nmol/L (7 ppb).

See MDA/2017/018 (issued 29 June 2017) for guidance on chromium and cobalt testing in MoM hip replacements and management recommendations.

_{To convert from nmol/L to µg/L (ppb): nmol/L x 0.052 = µg/L}

Click here for cobalt

Turnaround time

Referral lab quotes turnaround time of 5 days, however additional time must be allowed for packing, dispatch and delivery of sample, and return and processing of results.

Enquiries

Biochemistry (Referrals)