Patients with mild hypercalcemia (<12 mg / dL) have no indications for immediate treatment. It may be advisable to increase fluid intake to reduce the risk of nephrolithiasis.
Intermediate hypercalcemia (12-14 mg / dL) may not require immediate treatment. An acute rise in serum calcium can cause significant impairment in mental status and requires urgent treatment.
Severe hypercalcemia (> 14 mg / dL) should be treated;
The isotonic saline should be given at a rate of 200-300 mL / h and a rate of 100-150 mL / h urine output. If there is no heart / kidney failure, it is not necessary to give loop diuretics.
Calcitonin (4 IU / kg) should be given and serum calcium measured after hours. If hypocalcemic response is observed, this can be repeated every 6 to 12 hours (4-8 IU / kg).
Zolendronic acid (4 mg i.v., over a 15 minute period) should be started concurrently with treatment. The other alternative is pamidronate.
Administration of saline with calcitonin will cause a reduction in calcium in 12 to 48 hours. The bisphosphonate reduces serum calcium within 2 to 4 days.
Donesumab is an alternative drug in a patient with malignant, Zolendronic acid-resistant, severe hypercalcemia.
The most common cause of hypercalcemia in non-hospitalized patients is HYPERPARATHYROIDISM.
Hydration with isotonic NaCl
Hypovolemia causes hypercalcemia by impairing renal clearance of calcium.
With saline treatment, hypercalcemia on a moderate level often does not become normal. Simultaneous bisphosphonates should also be initiated. If necessary calcitonin can be started.
At pharmacological doses, calcitonin acts by increasing renal calcium excretion and, more importantly, by impairing osteoclast function and reducing bone resorption. Nasal form is not successful in hypercalcemia treatment.
Calcitonin is safe and does not have major toxicities. The effect is fast despite the weakness. It starts in six hours and reduces calcium up to 1-2 mg / dL maximum. Probably due to receptor down-regulation, tachyphylaxis develops within 48 hours.
Bisphosphonates are nonhidrolizable analogs of inorganic phosphate adsorbing to the surface of bone hydroxyapatite. It disrupts osteoclast-mediated bone resorption and impairs calcium release.
Although zoledronic acid has the potential to cause osteonecrosis of the jaw, it is a side effect that is more commonly seen in chronic use.
The efficacy of zolendronic acid 4 mg and 8 mg doses were similar. 8 mg was associated with more renal toxicity.
Pamidronate is more effective than etidronate or clodronate.
Ibandronate 2mg / 4mg / 6mg is also effective in hypercalcemia. The efficacy is greater at 4 mg and 6 mg, but duration of action is dose independent.
Ibandronate appears to be as effective as pamidronate.
Clodronate and etidronate are relatively low-impact first-generation bisphosphonates. If the other bisphosphonates are not aviable, these two agents can be used.
Where absorption of vitamin D-related dietary calcium is increased, glucocorticoids reduce the production of calcitriol within 2-5 days.
DenoSumab has a 60 mg injector and is used weekly.
It can also be used in chronic kidney failure. Optimal dosing is not clear in renal failure. The risk of hypocalcemia seems to be more in chronic kidney disease.
If the first dose is as low as 0.3 mg / kg, and if the target is not reached within 1 week, the second injection may be recommended as a prudent approach, considering the risk of hypocalcemia.
Measuring vitamin D levels prior to denosumab may also be warranted, because those with vitamin D deficiency are more susceptible to hypocalcemia. Even if the measurement of vitamin D levels is delayed, give vitamin D 50000 IU 1-2 days before donesumab; If the result is Vitamin D deficiency you will continue treatment; If there are no deficiencies, you will end up giving vitamin D. Some authors advocate this view.
It is the approach to be considered in the last stage.