At a glance
| Analyte | Total calcium |
|---|---|
| Also called | Ca, Serum calcium |
| Method | Colorimetric |
| Sample type | Serum, Plasma, Urine |
| Panel | Inorganic |
| Discipline | Clinical chemistry |
| Brand | Mindray |
What Calcium measures
Calcium in plasma exists in two pools: roughly half bound to albumin and other proteins, and the rest circulating free, which is the physiologically active fraction. This reagent measures the two together as total calcium. That distinction is the single most important thing to understand about the result, because a patient with a low albumin will show a low total calcium while their free calcium is entirely normal, and treating that as hypocalcaemia would be a mistake. Laboratories therefore interpret total calcium against the albumin measured on the same specimen. Calcium is requested in bone and parathyroid workups, in renal disease, in malignancy where it can rise sharply, and in the investigation of unexplained neuromuscular symptoms.
How Philippine laboratories run it
Ordered with phosphorus and alkaline phosphatase in the bone panel and alongside creatinine in renal work, which gives it a demand pattern tied to nephrology and endocrinology rather than to the annual-physical batches that drive the liver and lipid assays. Because interpretation depends on albumin, a laboratory offering calcium should ensure albumin is available on the same run rather than as a separate request, and both reagents should sit on the same schedule. Where a clinician needs the free fraction specifically, that is an ionised calcium measurement on an electrolyte analyzer and not this assay.
Analyzers it runs on
Calibrator, controls and companion tests
Delivered with its calibrator, both control levels and the rest of the inorganic panel, on the same schedule as Calcium.
Storage and handling
Refrigerated and kept closed when off the analyzer.
Buying Calcium in the Philippines
Calcium is supplied for the BS-600M, BS-430, BS-360E, BS-240Pro, BS-230 and BA-88A. We deliver it with Multi-Sera Calibrator and Chemistry Control Level 1, because a run held up waiting on a separate order costs the same shift a stock-out does. Delivery is scheduled against your monthly Calcium count, so the bench is not rationing tests in the last week of the month. How we plan clinical chemistry supply.
Questions about Calcium
Is this the same as ionised calcium?
No, and the difference matters clinically. This reagent measures total calcium, both the protein-bound and the free fractions together. Ionised calcium measures only the free, physiologically active fraction and is determined by an ion-selective electrode on an electrolyte analyzer, not by this chemistry. A clinician asking for ionised calcium is asking for a different measurement on a different instrument.
Why does a low albumin lower the calcium result?
Because about half the calcium in plasma is bound to albumin, and a total calcium measurement counts that bound fraction. When albumin falls, the bound pool falls with it and the total drops, even though the free active calcium is unchanged. This is why laboratories interpret total calcium against the albumin on the same sample rather than against the reference interval alone.
Order Calcium
Tell us your monthly Calcium volume and we will quote a supply schedule for BS-600M. We reply within one business day.
Request a quotation