Causes of Hypocalcemia

• Decreased free calcium:

• Hyperphosphatemia

• Alkalosis

• Intravascular complexing with citrate, lactate

• Acute pancreatitis

• Hypoparathyroidism:

• Impaired synthesis or secretion:

• Genetic: DiGeorge Syndrome HDR Syndrome (Hypoparathyroidism, deafness, renal anomaly) Sanjad-Sakati syndrome Mitochondrial disorders (eg, MELAS Syndrome) Defect of the calcium sensing receptor

• Autoimmune: Autoimmune polyglandular syndrome type 1 (APS1)

• Thyroid or parathyroid gland surgery

• Infiltration of parathyroid gland (eg, iron overload)

• Infection (eg, gram-negative sepsis, HIV)

• Pseudohypoparathyroidism (End organ resistance) Type 1Type 2

• Hypovitaminosis D:

• Impaired synthesis or intake

• Insufficient dietary intake and/or sun exposure

• Decreased gastrointestinal absorption

• Liver disease

• Renal disease

• Vitamin D resistance

• Hypomagnesemia

• Hungry bone syndrome

• Fluoride poisoning