Serum Calcium
Understanding Serum Calcium
What is Serum Calcium?
The Serum Calcium test, also known as a calcium blood test, measures the calcium level in the blood. Serum calcium levels are vital for various bodily functions, including maintaining strong bones and teeth, regulating muscle contractions (including the heart), transmitting nerve signals, and ensuring effective blood clotting. It is often done as part of routine health checkups.
Calcium is one of the important and abundant minerals in our body. It is essential for various bodily functions, such as nerve transmission, cell signaling, and muscle contraction. The body also needs calcium to keep the bones healthy and strong, for blood clotting, and to regulate heart rhythms.
The Serum Calcium test is performed if you experience weakness, fatigue, excessive urination and thirst, nausea, stomach pain, constipation, irregular heartbeat, brittle nails, weak and brittle bones, muscle cramps, irritability, or confusion. Furthermore, a calcium blood test aids in the diagnosis of conditions related to calcium metabolism, parathyroid disorders, kidney diseases, and bone health.
Regular calcium testing may also help monitor the treatment response for abnormal calcium levels, especially in critically ill patients like those suffering from cancer or kidney disorders. It is particularly crucial for individuals with chronic conditions to ensure optimal health.
Low calcium levels, known as hypocalcemia, can be linked to causes such as hypoparathyroidism, kidney diseases, malabsorption disorders, or vitamin D deficiency. On the other hand, high calcium levels, termed hypercalcemia, can be associated with symptoms signaling hyperparathyroidism, certain cancers, kidney dysfunction, or excessive calcium supplementation.
Usually, overnight fasting (8-12 hours) is preferred for this test. Do not eat or drink anything except water before the test. Test result ranges are approximate and may differ slightly between labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. These will help the doctor determine appropriate treatments, whether through calcium supplements, medications, dietary adjustments, or lifestyle modifications.
What is Serum Calcium used for?
The Serum Calcium test is done:
- As part of routine health checkups.
- If you have symptoms of abnormal calcium levels, such as excessive urination and thirst, constipation, irregular heartbeat, brittle nails, weak and brittle bones, muscle cramps, irritability, or confusion.
- To diagnose diseases that may cause calcium abnormalities, such as thyroid and parathyroid disorders, heart diseases, kidney diseases, bone disorders, and dental diseases and disorders that affect how your intestines absorb nutrients like calcium.
- To assess the effectiveness of treatments like calcium and vitamin D supplements in the body.
- To monitor treatment progress in conditions associated with the kidneys, heart, bones, thyroid, teeth, and certain types of cancers that may affect calcium levels in the body.
- To monitor calcium levels in people during and after blood transfusions or intravenous fluids, those undergoing major surgery, and those with blood protein abnormalities like low albumin.
What does Serum Calcium measure?
The Serum Calcium test measures the levels of calcium in the body. Calcium is the most abundant mineral in the body; most of it is present in the bones and teeth, and the remaining portion (around 1%) is found in the blood. It is usually present in two forms in blood in about equal amounts: "bound calcium," which is attached to proteins in the blood, and "free calcium or ionized calcium," which is not attached to any protein.
The Serum Calcium test cannot be used to check for lack of calcium in your diet or osteoporosis (loss of calcium from bones) as the body can have normal calcium levels even in dietary calcium deficiency. Moreover, the body can normalize mild calcium deficiency by releasing the calcium stored in bones.
Interpreting Serum Calcium results
Interpretations
Normal range: 8.5 to 10.5 mg/dL (2.2 to 2.7 mmol/L approx.)
Hypocalcemia: Below 8.5 mg/dL (Below 2.2 mmol/L approx.)
Hypercalcemia: Above 10.5 mg/dL (Above 2.7 mmol/L approx.)
Calcium concentration in the body is maintained within a narrow normal range between 8.5mg/dL and 10.5mg/dL.
Hypocalcemia or low blood calcium is indicated if calcium concentration lies below the normal range.
Hypercalcemia or high blood calcium is indicated if calcium concentration lies above the normal range.