Hypocalcemia
Hypocalcemia is a medical condition characterized by low calcium levels in the blood serum. The normal range of blood calcium is typically between 2.1–2.6 mmol/L (8.8–10.7 mg/dL, 4.3–5.2 mEq/L), while levels less than 2.1 mmol/L are defined as hypocalcemic. Mildly low levels that develop slowly often have no symptoms. Otherwise symptoms may include numbness, muscle spasms, seizures, confusion, or in extreme cases cardiac arrest.
| Hypocalcemia | |
|---|---|
| Specialty | Endocrinology |
| Symptoms | Numbness, muscle spasms, seizures, confusion |
| Complications | Cardiac arrest |
| Causes | Hypoparathyroidism, vitamin D deficiency, kidney failure, pancreatitis, calcium channel blocker overdose, rhabdomyolysis, tumor lysis syndrome, bisphosphonates |
| Diagnostic method | Blood serum < 2.1 mmol/L (corrected calcium or ionized calcium) |
| Treatment | Calcium supplements, vitamin D, magnesium sulfate. |
| Frequency | ~18% of people in hospital |
The most common cause for hypocalcemia is iatrogenic hypoparathyroidism. Other causes include other forms of hypoparathyroidism, vitamin D deficiency, kidney failure, pancreatitis, calcium channel blocker overdose, rhabdomyolysis, tumor lysis syndrome, and medications such as bisphosphonates or denosumab. Diagnosis should generally be confirmed by determining the corrected calcium or ionized calcium level. Specific changes may also be seen on an electrocardiogram (ECG).
Initial treatment for severe disease is with intravenous calcium chloride and possibly magnesium sulfate. Other treatments may include vitamin D, magnesium, and calcium supplements. If due to hypoparathyroidism, hydrochlorothiazide, phosphate binders, and a low salt diet may also be recommended. About 18% of people who are being treated in hospital have hypocalcemia.