This article defines low, high, and normal levels of calcium in the blood in healthy individuals.
The total calcium level includes what are termed “bound” and “unbound” calcium.
Bound calcium is calcium attached to a protein, usuallyalbumin(a protein made in the liver).
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Unbound calcium is not attached to a protein.
It’s the active form of calcium, called free or ionized calcium.
In most cases, a total calcium blood level is ordered.
More severe symptoms include seizures and heart failure.
Surgicalhypoparathyroidismdescribes an underactive parathyroid gland and is the most common cause of low calcium levels.
Function of the Parathyroid Gland
The parathyroid gland produces parathyroid hormone (PTH).
Also, although it’s unknown precisely why, blood calcium levels vary slightly among different age groups.
Specifically, blood calcium levels are a bit higher in children than in adults.
Moderate hypercalcemia is between 12.0 and 13.9 mg/dL, whereas severe hypercalcemia is greater than 14.0 mg/dL.
Severe hypercalcemia is associated with life-threatening problems likeheart arrhythmia(irregular or abnormal heartbeat), confusion, andcoma.
Primary hyperparathyroidismdescribes an overactive parathyroid gland, resulting in excess PTH production.
This protein acts similarly to PTH, drawing calcium out into the bloodstream from the bone.
Another cause of hypercalcemia of malignancy is the spread (metastasis) of cancer cells into bone.
This invasion into bone releases calcium into the bloodstream.
What Does a BMP and CMP Measure?
It usually takes just minutes to draw the blood.
Be sure to reach out to your healthcare provider to discuss your results.
Additional causes include vitamin D and magnesium deficiency, among others.
Speak with a healthcare provider if you have an abnormal calcium blood level.
More blood tests are usually performed to confirm the finding and help diagnose the cause.
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