Calcium

This test is used to find out the both bound and unbound calcium levels in the blood. Bound calcium is that the calcium attached to the other anions and to proteins like albumin. Unbound calcium is calcium that is not bounded to proteins and freely circulating in the blood. Unbound calcium is also known as ionized calcium or free calcium.

What is Calcium?

Calcium is one of the important minerals present in the body. It is naturally presented in the food items like cheese, almonds, beans, yogurt, seeds, milk, cereals, fruit juices, fish with soft bones etc. It is important for the body to maintain the strong bones and to carry out many functions in the body. It is required for muscles to move and for nerves to carry the messages between the brain and the body parts. This also helps the blood vessels to move blood throughout the body. It also has a role in the release of hormones and enzymes that affect most of the functions in the human body.

Most of the calcium in the body is stored in the bones. Calcium metabolism is regulated by the parathyroid hormone (PTH)-vitamin D endocrine system. The active form of vitamin-d is calcitriol and it stimulates the calcium absorption from the gut. Absorption of calcium is done by active transport and passive diffusion. Active transport is dependent on the action of calcitriol and vitamin-d receptors (VDR). Active transport occurs primarily in the duodenum where VDR presents high in concentration. Passive diffusion involves the movement of calcium between mucosal cells. It depends on the electrochemical gradients and occurs throughout the intestine. Active transport of calcium occurs when there is a low or moderate intake of calcium. Passive diffusion takes place during high calcium intakes. Calcium is mainly excreted through urine and feces and sweat. Calcium is reabsorbed in the urinary tract and the excreted calcium through feces is unabsorbed intestinal calcium.

Calcium is an important component of the skeleton and is necessary for its structure, tissue rigidity, strength, and elasticity. Calcium is needed for bone formation and resorption. Bone marrow cavity acts as a major site for the red blood cell production and immune system. So, to maintain healthy bone marrows calcium is needed for bones. Calcium is preserved within the non-bone tissues of the body by bones undergoing constant remodeling through bone resorption. Calcium helps to maintain acid-base balance in the blood. It also maintains healthy blood pressure. It is also used to treat osteoporosis which is a disease of the bones where bones become fragile and easy to break. It as lowers the risk of developing a colon or rectum cancer and prostate cancer.

Why this test is performed?

The Calcium Blood Test is done to know whether an individual is having normal or abnormal calcium levels in the blood of the body. The doctor may ask to perform this test if an individual is suffering from conditions like hypercalcemia (high levels of calcium in the blood), hypocalcemia (low levels of calcium in the blood), osteoarthritis, osteoporosis, kidney stones, malformation of the skeleton. This test is also done to determine the risk of developing a bone disorder. If an individual is on the treatment of anti-diuretic medications like hydrochlorothiazide, chlorthalidone etc., then the doctor may ask to perform this test to evaluate and to check the effectiveness of the treatment and calcium levels in the body. This helps the doctor to rule out the patient disease condition. If an individual is suffering from symptoms like muscle cramps, lethargy, dermatitis, mental confusion, weakness then the doctor may ask to do the Calcium Blood Test. The doctor may recommend this test for pregnant women to check the possibilities of occurrence of pre-eclampsia (pregnancy complication characterized by high blood pressure).

Generally, when a patient is diagnosed with kidney failure, arthritis or malnutrition visits hospital for a general check-up, the doctor may ask to undergo the Calcium blood test which gives a better status of the condition. This test is also performed to provide a clear idea regarding the malnutrition of an individual and kidney dysfunction. Mostly, this test is done along with other mineral tests to confirm the diagnosis.

Precautions:

Drugs like lithium, thiazides, tamoxifen etc may change the levels of Calcium in the blood. So inform your doctor prior to the test if you are on these medications.

If test results are more than the normal range then it may indicate that there may be conditions likes kidney dysfunction or kidney failure, liver disease, hyperthyroidism, adrenal gland failure, sarcoidosis, hyperparathyroidism, T-cell lymphoma (Rare form of cancer that begins in the white blood cells and attacks the skin), multiple myeloma (rare form of cancer in plasma cells), metastatic bone tumour (a form of cancer that starts in bones and may spread to lung and kidneys), paget disease (failure of replacement of old bone tissues with new bone tissues), high consumption of calcium msupplements, hypercalcemia (high levels of calcium levels in the blood), parathyroid tumour (cancer in the parathyroid gland), intense thirst, bone pains, tiredness, vomiting, weakness, decreased apetite (decreased derire to eat), abdominal pain, overuse of antacids, tuberculosis (bacterial infection of the lungs and also known as TB), prolonged immobilization (increased bed rest without moving), constipation (difficulty in emptying bowel or hardened feces), kidney transplant, high vitamin-D in diet.

If test results are less than the normal range, then it indicates that there may be a chance for conditions like protein deficiency (decreased levels of albumin), renal insufficiency (kidney loose the ability to remove waste and balance fluids), lethargy (lack of energy and enthusiasm), malformation of skeleton, hypoparathyroidism (decreased secretion of parathyroid hormone), irregular heartbeat, seizures (disturbances in the brain nerve cell activity), muscle cramps (overuse of the muscle), osteoporosis (the bone becomes weak and easy to break), osteopenia (condition in which the body doesn’t make new bone as fast as it reabsorbs the old bone), tingling in feet or hand, nerve problems, pancreatitis (inflammation in the pancreas) , hypocalcemia (low levels of calcium in the blood), low levels calcium in diet, magnesium deficiency, vitamin-D deficiency, malnutrition (insufficient nutrients in the body), malabsorption of calcium (condition that prevents absorption of calcium through the small intestine), intestinal disorders and inflammation, liver disease.