From the Guidelines

Hypocalcemia is a condition characterized by low calcium levels in the blood.

Hypocalcemia can be caused by various factors, including hypoparathyroidism, vitamin D deficiency, and kidney disease 1.
It can also be a result of certain medical treatments, such as calcimimetic therapy, which is used to treat secondary hyperparathyroidism in patients with chronic kidney disease (CKD) 1.

Hypocalcemia can lead to various symptoms, including fatigue, emotional irritability, abnormal involuntary movements, seizures, and cardiac arrhythmias 1.
It can also increase the risk of osteopenia/osteoporosis and may predispose to nonfatal cardiovascular events 1.

Diagnosis of hypocalcemia typically involves measurements of pH-corrected ionized calcium, magnesium, parathyroid hormone, and creatinine concentrations 1.
Treatment of hypocalcemia usually involves calcium and vitamin D supplementation, and in some cases, treatment with hormonally active metabolites of vitamin D may be necessary 1.

In patients with CKD, hypocalcemia should be treated to prevent secondary hyperparathyroidism and adverse effects on bone mineralization 1.
However, high calcium intake should be avoided in CKD patients to prevent hypercalcemia and soft-tissue calcification 1.
In patients with 22q11.2 deletion syndrome, hypocalcemia is a common finding and may require regular monitoring and treatment to prevent adverse consequences 1.

From the Research

Hypocalcemia is a condition characterized by low serum calcium levels, which can be life-threatening if severe 2.
It occurs in conjunction with multiple disorders and can have acute or chronic manifestations 2, 3.
Symptoms of acute hypocalcemia include neuromuscular irritability, tetany, and seizures, which can be rapidly resolved with intravenous administration of calcium gluconate 2.

Hypoparathyroidism, characterized by impaired secretion of parathyroid hormone (PTH), is a classic cause of chronic hypocalcemia 2.
Disorders that disrupt the metabolism of vitamin D can also lead to chronic hypocalcemia, as vitamin D is responsible for increasing the gut absorption of dietary calcium 2.
Certain pharmacological agents, such as bisphosphonates and cisplatin, can induce hypocalcemia 4.
Critically ill patients are at risk of developing hypocalcemia due to various factors, including hypoalbuminemia and disorders of acid-base balance 3, 5.

Measurement of ionized calcium can be critical in determining an individual's true serum calcium status, especially in critically ill patients 3, 5.
Treatment of hypocalcemia depends on the underlying disorder and the severity of the condition 6, 2.
Acute management aims to ameliorate the acute manifestations of hypocalcemia, while long-term management involves careful titration of calcium and vitamin D supplementation to avoid symptoms of hypocalcemia and hypercalciuria 6, 2.
The correction of hypocalcemia in critically ill patients is a topic of debate, with some studies suggesting that it may not improve clinical outcomes and may even lead to higher mortality and organ dysfunction in certain cases 5.