Hypocalcemia

Abnormally low serum calcium concentration (ionized/free calcium range: 1.16-1.31 mmol/L or 4.65-5.25 mg/dL, total calcium range: 2.12-2.62 mmol/L or 8.5-10.5 mg/dL), leading to increased neuromuscular excitability and potential cardiac, neurologic, and neuromuscular complications. Possible causes are hypoparathyroidism, DiGeorge syndrome, vitamin D deficiency (lack of dietary intake, insufficient sun exposure, or malabsorption issues), kidney failure, hypomagnesemia, pancreatitis, medications (corticosteroids, phenobarbital, bisphosphonates, and specific chemotherapy), and malnutrition.