Also known as Ca+2; Calcium - serum; Ca++
What is a calcium ionized test?
Ionized calcium is present in our bloodstream; it circulates freely without binding with proteins. It is also known as free calcium. Calcium levels can be impacted by the parathyroid hormone, kidneys, or certain types of cancers. Decreased free calcium levels may cause an unstable heart rate and muscular spasms. Calcium comes in the bracket of vital minerals used in many necessary metabolic processes. It helps improve the bones and makes your muscles function better. A serum calcium blood test estimates the total calcium in your blood. These include ionized calcium, calcium attached to minerals called anions, and calcium bound to proteins like albumin. However, ionized calcium is the most active form.
What is the test used for?
Serum calcium tests are usually of two types:
Total calcium calculates the calcium bound to specific proteins in your blood. On the other hand, the ionized calcium test measures these proteins' free or unattached calcium.
Why and when do you need a calcium ionized test?
You may need to check your blood calcium levels if your kidneys are not functioning correctly. Besides, this test is also used to assess specific cancers and the functioning of your parathyroid gland.
The ionized calcium test provides more details about active, free circulating calcium. If you have abnormal protein levels (albumin or immunoglobins) in your blood, this test may be required to check your ionized calcium levels. Suppose the ratio between bound calcium and free calcium isn't normal. In that case, your doctor wants to know the reason—free calcium and attached calcium each make-up half of your body's total calcium. Higher than normal values indicates various health issues.
Your ionized calcium levels are checked in the following scenarios:
- You receive regular blood transfusions
- You're suffering from life-threatening health conditions
- Your blood protein levels are high
- You're planning to undergo major surgery in the coming days
In these cases, it's essential to comprehend precisely how much free calcium you have available.
Low levels of free calcium in your body cause problems in your heart rate, leading to muscle spasms, and in severe cases, it might result in coma. Your doctor may advise an ionized calcium test if you feel numbness around your mouth or in your hands and feet. Muscle spasms also reinforce that your body may be dealing with calcium problems.
What kind of sample is required for the test?
An ionized calcium test utilizes a small amount of your blood.
- A lab technician or phlebotomist will get a blood sample by venipuncture.
- He will cleanse an area of skin on your arm or hand, insert a needle into your vein through your skin, and then draw the required amount of blood into a test tube. You may experience some mild pain or pinching sensation during the procedure.
- You'll be advised to apply pressure to the site where the hand entered your skin.
- He will then wrap a bandage around your arm and ask you to avoid using that arm for heavy lifting throughout the day.
Do you need to prepare for the test?
Your doctor will ask you to fast for six hours before your blood test for an ionized calcium test. It implies that you can only drink water during this period. No solid food should be consumed 6 hours before the test.
Discuss all your medications with your doctor. He may advise you to stop taking certain medicines before the test, but don't stop using these medications before your doctor's consent.
Following drugs can alter your ionized calcium levels:
- Calcium salts
- Thiazide diuretics
Are there any risks to the test?
There are some rare risks involved in taking a blood sample, including:
- Lightheadedness or fainting
- Hematoma, which happens when blood collects under your skin
- Excessive bleeding
After the procedure, bleeding for an extended period may indicate a more severe bleeding condition.
What do the test results mean?
Normal levels of ionized calcium vary in adults and children. A group of 4.64 to 5.28 milligrams per deciliter (mg/dL) in adults is standard. An average ionized calcium level in kids is 4.8 to 5.52 mg/dL.
Low levels of calcium in your body can be due to:
- Hypoparathyroidism (underactive parathyroid gland)
- Inherited resistance to parathyroid hormone
- Malabsorption of calcium
- A vitamin D deficiency
- Osteomalacia (A disease in which vitamin D deficiency causes softening of bones)
- A magnesium deficiency
- High phosphorus levels
- Acute pancreatitis, which is an inflammation of the pancreas
- Kidney failure
High levels of ionized calcium in your blood mean:
- Hyperparathyroidism, which is an overactive parathyroid gland
- A sedentary lifestyle or lack of mobility
- When you consume too much milk, antacids, or calcium carbonate over time, Milk-alkali syndrome results in high calcium levels in your blood.
- Multiple myeloma, which is cancer of the plasma cells
- Paget's disease, which is a disorder that results in deformation due to abnormal bone destruction and growth
- Sarcoidosis, which is an inflammatory condition that affects the eyes, skin, and other organs
- Tuberculosis, caused by the bacterium Mycobacterium tuberculosis, is a potentially fatal disease caused by the
- A kidney transplant
- The use of thiazide diuretics
- Certain kinds of tumors
- An overdose of vitamin D
Your doctor will examine your results with you. They'll also help determine your next steps if any are needed.
Related Tests: Vitamin D Test, Parathyroid Hormone test(PTH), Phosphorus, Magnesium Blood test, Albumin Blood Test, Comprehensive Metabolic Panel (CMP), Basic Metabolic Panel (BMP), Kidney Stone Testing
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