Introduction: The extremely rare but life-threatening hypercalcemic crisis is caused by an exacerbation of a chronic hyperparathyroidism. The etiologic reasons for this exacerbation are conditions which increase the serum calcium level in addition to the hyperparathyroidism with a complete breakdown of the calcium homeostasis, e. g. malignant tumors, primary and tertiary hyperparathyroidism, vitamin D poisoning or overdoses of calcium, vitamin D and calcium-containing ionizer in patients with renal insufficiency.
Methods: We present the clinical course of five patients with an acute hypercalcemic crisis and discuss the diagnostic procedure and the principles of surgical treatment with regard to the current literature.
Results: A hypercalcemic crisis develops if the total serum calcium concentration is over 4 mmol/l and parathormone over 90 pmol/l. The resulting syndrome is manifested by nausea and vomiting, polyuria and consecutive dehydration and hypotonia culminating in lethargy, hallucinations and coma. Hypercalcemia is the single most important diagnostic finding.
Conclusion: The emergency therapy predominantly consists on the one hand in rehydration and parallel stimulation of diuresis. Urgent surgery is required if conservative therapy is not successful.