When Blood Tests Show Low Blood Calcium
Hypocalcemia refers to low levels of calcium found on a blood test.
Hypocalcemia is a particular problem for people who are hospitalized.
This article will take you through the symptoms and causes of hypocalcemia.
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It also addresses the diagnosis and treatment options available when your blood calcium levels fall too low.
What Happens When Calcium Levels Are Low?
If your calcium is only a little low, you might not notice any symptoms from hypocalcemia.
You are also less likely to experience symptoms if your calcium has been gradually lowering over time.
The signs of hypocalcemia include the following:
However, not everyone will experience all these symptoms.
Sometimes symptoms are relatively mild, but in other cases, they may cause life-threatening problems.
In someone who is already critically ill, having hypocalcemia may increase a persons risk of death.
Calcium is involved in many important biological processes.
For example, it plays roles in blood clotting and in helping certain enzymes to function.
It is also critical for proper signaling in your nerves and muscles, including your heart muscle.
Because of this, your body works to tightly regulate the amount of calcium present in your blood.
Normally, the action of PTH brings the calcium back into a normal range.
Underlying Causes Leading to Hypocalcemia
Hypocalcemia can have many different potential underlying causes.
Low vitamin D is also another important cause of hypocalcemia.
This hormone plays an important role in your bodys ability to absorb and utilize calcium.
For example, abnormal levels of the electrolytes magnesium and phosphate might indirectly cause hypocalcemia.
Some other less common causes of hypocalcemia includepancreatitisand cancer which has spread to the bones.
Medications sometimes cause hypocalcemia as a side effect.
Diagnosis of Hypocalcemia
Various signs and symptoms might make a clinician suspect hypocalcemia.
Your healthcare provider will take a full medical history and ask you about your recent symptoms.
Things like muscle cramps or pain and tingling in the fingers might make the clinician think of hypocalcemia.
A complete exam is also an important part of diagnosis.
Your healthcare provider might tap you lightly at a certain place on your cheek.
People with hypocalcemia may involuntarily contract their facial muscles in response.
Blood Tests
A definitive diagnosis of hypocalcemia requires ablood test for calcium.
Calcium is usually first assessed through a total calcium blood test.
If this test is low, you might need a test of youralbumin.
This can help your clinician get a more accurate idea about whether your calcium level is a problem.
Hypocalcemia is usually defined as having a corrected total serum calcium of less than 2.12 mmol/L.
“Corrected refers to a certain way of measuring calcium that accounts for albumin.
However, recognizing that hypocalcemia is present is only the first step.
This often requires additional testing.
These include the underlying cause and the severity of the problem.
This can raise a persons calcium level more quickly than oral calcium supplements.
People receiving IV calcium need to be carefully monitored in a hospital setting.
People who have calcium that is not as low can usually takeoral calcium supplementsinstead.
You may need to take these over a long period.
Vitamin D is also often a key component of treatment.
Depending on the situation, you might need to take other substances important for calcium metabolism, like magnesium.
Or you might need to stop taking a medication that lowers your calcium too much.
Other treatments may be necessary, depending on the circumstances.
For example, you might need treatment for an underlying condition, like kidney or liver disease.
Some people with hypoparathyroidism take a PTH replacement hormone that may help increase calcium to normal levels.
You are likely to need follow-up monitoring if you are found to have hypocalcemia.
This is to check that your calcium has returned to normal and your treatment hasnt increased it too much.
This can cause elevated calcium (hypercalcemia) which causes different medical problems.
Your healthcare provider will help tailor your treatment and monitoring schedule to your specific circumstance.
Summary
Hypocalcemia is low levels of calcium in the blood.
Hypocalcemia can be especially problematic for those who are already sick.
Fortunately, low calcium levels can usually be corrected intravenously or through supplementation.
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