calciumniveauer

Calciumniveauer refers to the concentration of calcium in the body, with a focus on calcium in the blood. It is usually described as total serum calcium or the biologically active fraction, ionized calcium. Ionized calcium is the portion that participates in most physiological processes and can be measured directly, while total calcium includes protein-bound and complexed forms.

Calcium homeostasis is tightly regulated by hormonal and renal mechanisms. The parathyroid hormone (PTH), vitamin D, and calcitonin coordinate with the kidneys, bones, and intestines to maintain stable calcium levels. Bones act as a reservoir, releasing or storing calcium as needed; the kidneys adjust excretion and reabsorption, and the gut determines intestinal absorption. Adequate magnesium status also supports proper calcium regulation.

Measurement and reference ranges vary by method and age. In adults, normal total serum calcium is about 2.12–2.62 mmol/L (8.5–10.5 mg/dL). Ionized calcium typically ranges from about 1.10–1.30 mmol/L. Because albumin binds calcium, corrected calcium may be reported when albumin levels are abnormal: corrected calcium = measured total calcium + 0.8 × (4 − albumin in g/dL).

Abnormal calcium levels have clinical significance. Hypocalcemia can cause neuromuscular irritability, tingling, and tetany, and may result from hypoparathyroidism, vitamin D deficiency, chronic kidney disease, or pancreatitis. Hypercalcemia can cause thirst, polyuria, constipation, and cognitive changes, and may stem from primary hyperparathyroidism, malignancy with bone involvement, granulomatous disease, excessive vitamin D, or certain medications.

Calciumniveauer are routinely assessed in metabolic panels and during evaluation of endocrine or renal disorders. Management depends on underlying cause and severity, ranging from supplementation and vitamin D optimization to treatments targeting hypercalcemia or bone metabolism.