From the Guidelines
Hypocalcemia should be treated with caution, considering the potential harm associated with a positive calcium balance, and the goal should be to maintain normal serum calcium levels, rather than aggressively correcting hypocalcemia, especially in patients with chronic kidney disease (CKD) 1.
Treatment Approach
The treatment of hypocalcemia depends on the severity and underlying cause of the condition. For severe symptomatic hypocalcemia, immediate intravenous calcium is necessary, usually as calcium gluconate 1-2 grams (10-20 mL of 10% solution) administered slowly over 10-20 minutes, followed by a continuous infusion of calcium gluconate at 0.5-1.5 mg/kg/hour.
- For chronic or less severe cases, oral calcium supplements such as calcium carbonate 1000-2000 mg elemental calcium daily in divided doses are recommended, often combined with vitamin D supplementation (calcitriol 0.25-1 mcg daily or ergocalciferol 50,000 IU weekly) 1.
- Patients should be monitored for symptoms like muscle cramps, tingling in fingers and toes, seizures, and cardiac arrhythmias.
Monitoring and Prevention
Hypocalcemia occurs when calcium homeostasis is disrupted, commonly due to vitamin D deficiency, hypoparathyroidism, chronic kidney disease, or medication effects.
- Calcium is essential for nerve conduction, muscle contraction, blood clotting, and bone health, which explains the diverse symptoms when levels are low.
- Regular monitoring of serum calcium, phosphorus, magnesium, and parathyroid hormone levels is important during treatment.
- In patients with CKD G5D, using a dialysate calcium concentration between 1.25 and 1.50 mmol/L (2.5 and 3.0 mEq/L) is suggested to avoid hypercalcemia 1.
Special Considerations
In adults with 22q11.2 deletion syndrome, hypocalcemia is common and may be associated with hypoparathyroidism, hypothyroidism, and hypomagnesemia 1.
- Daily calcium and vitamin D supplementation are recommended for all adults with 22q11.2DS.
- Magnesium supplementation for those with hypomagnesemia is indicated.
- Treatment with hormonally active metabolites of vitamin D for more severe hypocalcemia usually requires consultation with an endocrinologist.
From the Research
Definition and Causes of Hypocalcemia
- Hypocalcemia is a condition characterized by low serum calcium levels, which can be life-threatening if severe 2, 3.
- It can occur in conjunction with multiple disorders, including hypoparathyroidism, vitamin D deficiency, and resistance to parathyroid hormone (PTH) or vitamin D 2, 4.
- The most frequent cause of hypocalcemia is postsurgical hypoparathyroidism, while other causes include autoimmune destruction of the parathyroid glands and genetic disorders 3, 5.
Symptoms and Diagnosis of Hypocalcemia
- Symptoms of acute hypocalcemia include neuromuscular irritability, tetany, and seizures, which can be rapidly resolved with intravenous administration of calcium gluconate 2, 6.
- Chronic hypocalcemia often has more subtle manifestations, and diagnosis requires knowledge of the factors that influence calcium homeostasis 2.
- Biochemical manifestations of hypocalcemia include hypocalcemia, low or undetectable levels of PTH, hyperphosphatemia, and low levels of 1,25-dihydroxyvitamin D 5.
Treatment and Management of Hypocalcemia
- Treatment of acute hypocalcemia involves intravenous calcium infusion to raise calcium levels and resolve symptoms 3, 6.
- Oral calcium and/or vitamin D supplementation is the most frequently used treatment for chronic hypocalcemia 3, 4.
- In hypoparathyroidism, replacement therapy with recombinant human PTH(1-84) has been approved and can effectively correct serum calcium levels and reduce the daily requirements of calcium and active vitamin D supplements 3, 5.
- Conventional treatment with calcium and active vitamin D can maintain serum calcium levels, but high doses may be required, adding to the risk of long-term soft tissue calcifications 5.