International Journal of Clinical Case Reports 2017, Vol.7, No.9, 38-41
40
hours. The goal of this regimen is to achieve a urine output of 200 ml per hour. It usually decreases serum calcium
levels by 1-3 mg/dl. The addition of loop diuretics to saline infusion has been advocated to enhance renal calcium
leak, but it should be administered after adequate hydration has taken place because diuretic- induced volume
contraction can worsen the hypercalcemia. Therefore, diuretics are best reserved for those patients with
compromised heart function (LeGrand et al., 2008).
Bisphosphonates are pyrophosphate analogues that are deposited in bone and lower serum calcium levels via
multiple effects on osteoclasts, one of which is inhibition of osteoclastic bone resorption. Because of their
efficiency in normalizing serum calcium, they should be considered for use early in the course of treatment of
severe hypercalcemia. Intravenous bisphosphonates have been successfully used in the treatment of severe
hypercalcemia related to parathyroid adenoma or carcinoma as in our patients (Witteveen et al., 2010). The effect
of a parenteral bisphosphonate to lower serum calcium is apparent within 2-4 days, with maximal effect within
7-10 days after commencing treatment. The effect can persist for 7-30 days. Zoledronic acid, the bisphosphonates
we used in our patients has proven efficacious in the treatment of severe hypercalcemia with a longer duration of
action (Sabry and Habib, 2011).
Glucocorticoids have been widely used in the management of severe hypercalcemia, though; they are usually not
effective in the treatment of hypercalcemia related to primary hyperparathyroidism. Glucocorticoids lower
calcium levels by decreasing intestinal absorption of calcium via decreased synthesis of 1, 25-dihydroxy vitamin
D and by increasing urinary calcium excretion (Kristensen et al., 1992).
Calcitonin is another therapeutic option to inhibit osteoclastic resorption. It has a rapid onset of action, causing
serum calcium levels to fall within hours of administration. It can be used in conjunction with a bisphosphonates
to more rapid reduction of serum calcium levels. It is usually given intramuscularly or subcutaneously. However,
the efficacy of calcitonin is transient due to rapidly acquired resistance (Ljunghall, 1989).
Hemodialysis against a low- or zero-calcium dialysate is effective in temporarily reducing the serum calcium level
and has been sometimes, successfully used in the treatment of severe hypercalcemia (Wang et al., 2009).
Treatment of the underlying etiology is essential. It is surgical and it consists in a parathyroidectomy. After
parathyroidectomy, patients are at risk of rapid and sharp decline of calcium levels in the postoperative period and
may require large amounts of calcium infusion as we observed in two of our patients. The risk of postoperative
hypocalcemia is attributed to the severity of the disease (Harjit et al., 2007).
4 Conclusions
Severe hypercalcemia is an endocrine emergency that requires rapid action to prevent cardiac, neurological and
renal complications. The diagnosis should be considered in any patient with known parathyroid disease who
presents with acute clinical picture, we also emphasize on the importance of early diagnosis and treatment of
hypercalcemia to improve the prognosis.
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to this article.
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