Calcium (serum)

 

Alternative names, keywords

Ca

Samples required

● Clotted blood (gold cap, 5 mL tube). Smaller tubes are available for paediatric samples.

Observe correct sample draw order to avoid EDTA contamination e.g. from FBC tubes. Information on draw order is available here.

Test indications

Disorders of calcium metabolism.

Hypercalcaemia is a treatable cause of abdominal pains (+/- renal calculi). It may contribute to distress in malignancy.

Test information

Adjusted calcium = total calcium - 0.017 x (albumin - 45.5)

Source: locally derived

Factors affecting test performance/ results

EDTA will cause falsely low results - avoid contamination of serum samples.

Intravenously administered gadolinium-containing MRI contrast media (Omniscan® and Optimark®) can interfere if at supra-therapeutic concentrations.

In very rare cases, gammopathy, in particular type IgM (Waldenström’s macroglobulinemia), may cause unreliable results.

Results should always be assessed in conjunction with the patient’s medical history, clinical examination and other findings.

Reference range
18 - 60 years 2.15 - 2.50 mmol/L
> 60 years 2.20 - 2.55 mmol/L
 
0 - 10 days 1.90 - 2.60 mmol/L
10 days to 2 years 2.25 - 2.75 mmol/L
2 to 12 years 2.20 - 2.70 mmol/L
12 to 18 years 2.10 - 2.55 mmol/L

Source: Roche Cobas® Calcium kit insert 2023-09, V9.0

Turnaround time

Same day (within 1h if urgent)

Enquiries

Biochemistry (Automation)
 
Details