Calcium, Ionized, Serum

Casandra

Casandra Test Code AR66842Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 0020135CPT Code 82330

Calcium, Ionized, Serum

Also known as: IONCA-S

Clinical Use

Order Test

Use

This test is used to assess calcium status by measuring ionized calcium levels in the serum. Ionized calcium is the physiologically active form of calcium, and its measurement is critical in evaluating calcium metabolism in various clinical conditions such as kidney stone disease, thyroid nodules, and hypercalcemia. It aids in diagnosing and monitoring conditions that affect calcium levels, including parathyroid disorders and malignancies.

Special Instructions

The test requires collection in a serum separator tube. It is crucial not to open or split the specimen, freeze the separator tube, or expose the specimen to air during collection or transport. The specimen should be centrifuged with the stopper in place within one hour of collection and transported in the original tube. It is recommended to interpret the ionized calcium normalized to pH 7.4 with caution, considering the patient's acid/base status.

Limitations

The test's accuracy may be affected by exposure to air, which can artificially increase specimen pH or by delayed processing, which can decrease it. Accurate determination of in vivo pH is best performed by arterial blood gas testing. The ionized calcium normalized to pH 7.4 should be interpreted cautiously as it may not reflect the accurate physiologic state unless the patient's acid/base status is known.

Test Details

FDA Approved

New York Approved

Methodology

Other

Biomarkers

Ionized Calcium (ISE)

Analyte

Ionized Calcium • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

Ionized Calcium (pH 7.4)

Analyte

Ionized Calcium at pH 7.4 • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

LOINC Codes

Result Codes

12180-6
19072-8

Result Turnaround Time

1 day

Specimen

Serum

Volume

5 mL

Minimum Volume

0.5 mL

Container

Original serum separator tube

Collection Instructions

Collect specimen in a serum separator tube. Do not open or split the specimen, and do not freeze the separator tube. Avoid exposure to air during collection and transport. Centrifuge with stopper in place within one hour of collection.