- Last edited on February 19, 2023
Hypercalcemia and Hyperparathyroidism
Primer
Hypercalcemia and hyperparathyroidism are frequently under-diagnosed in psychiatric practice and there are recommendations that calcium levels should be monitored in patients on long‐term treatment.[1] Like with other electrolyte and fluid imbalances (see: hyponatremia, hypokalemia, hypomagnesemia, hypocalcemia),[2] hypocalcemia can cause neuropsychiatric symptoms. Long-term lithium can cause hypercalcemia and hyperparathyroidism.
Signs and Symptoms
Sequelae of long-term chronic hypercalcemia includes renal stones, osteoporosis, dyspepsia, hypertension and renal impairment. Symptoms of hypercalcemia (and consequently hyperparathyroidism) can also mimic as psychiatric disorders, with disturbances of mood, energy, and cognition.
Mnemonic
The mnemonicpainful bones
(abnormal bone remodeling), renal stones
(kidney stones from hypercalciuria), abdominal groans
(hypercalcemia-induced ileus and abdominal pain), thrones
(urinary frequency), and psychic moans
(depression) can be used to recall the common symptoms of hypercalcemia.
Causes
Lithium
Lithium increases the risk of hypercalcemia and hyperparathyroidism (prevalence of ~5%).[3] Lithium is thought to cause hyperparathyroidism due to it altering the set point of receptors that sense calcium in parathyroid cells, and thus causing excess parathyroid hormone release.[4] Up to 10% of patients on long-term lithium treatment develop hypercalcaemia and hyperparathyroidism, and this is even higher in the geriatric population.[5]
Other
Hyperparathyroidism can occur due to primary, secondary, or tertiary causes. Primary causes include parathyroid adenomas, and carcinomas. Secondary causes include decreased calcium absorption, vitamin D deficiency, and chronic kidney disease. Tertiary causes include refractory hyperparathyroidism from chronic renal disease.
Comparison
Comparison of Various Electrolyte Disturbances
Hypo (Low Concentration) | Hyper (High Concentration) | |
---|---|---|
Sodium | Hyponatremia: Nausea, malaise, stupor, coma, seizures | Irritability, stupor, coma |
Potassium | Hypokalemia: Arrhythmias, muscle cramps, spasm, and weakness. ECGs will show U waves and flattened T waves | Arrhythmias, muscle weakness. ECGs will show Wide QRS and peaked T waves. |
Calcium | Hypocalcemia: Tetany, seizures, QT prolongation, twitching (e.g. - Chvostek sign), spasm (e.g. - Trousseau sign) | Hypercalcemia: Stones (renal), bones (pain), groans (abdominal pain), thrones (urinary frequency), psychiatric overtones (anxiety, altered mental status) |
Magnesium | Hypomagnesmia: Tetany, torsades de pointes, hypokalemia, hypocalcemia | Decreased deep tendon reflexes, hypotension, lethargy, bradycardia, cardiac arrest, hypocalcemia |
Phosphate | Bone loss, osteomalacia (adults), rickets (children) | Renal stones, metastatic calcifications, hypocalcemia |
Treatment
If hyperparathyroidism is thought to be due to lithium, then stopping lithium is the definitive treatment for reversing symptoms of hyperparathyoidism. Otherwise, a parathyroidectomy is the only cure for hyperparathyroidism.