Acute Hypercalcemia

Hypercalcemia is a frequent condition, especially in cancer patients, sometimes difficult to diagnose because of its clinical presentation, mimicking other diseases. Severe elevation of serum calcium generally gives mild and non-specific symptoms, ranging from fatigue, nausea, vomiting, abdominal pain, and up to mental status deterioration and cardiac arrhythmias. It is crucial to recognize acute hypercalcemia soon, and treat it aggressively. The severity of clinical findings depends on both the calcium level and the rate at which it develops. The first line treatment is massive rehydration with intravenous saline 0.9% to reach normovolemia, using invasive or noninvasive monitoring. This helps eliminating calcium excretion in the urine. When hemodynamic status or renal function is impaired, dialysis should be considered. Only when normovolemic status is achieved and renal function restored, furosemide administration can help to further increase urinary excretion of calcium. The second step is to inhibit osteoclastic bone resorption, which is possible with both bisphosphonate and non-bisphosphonate drugs. After the emergency treatment, it is important to diagnose and treat the underlying disease, such as hematological malignancy or other malignancies, while patients with primary hyperparathyroidism should be considered for surgery within a few days.