Endocrine Abstracts

Introduction: Severe hypercalcemia is a life-threatening condition which should be managed urgently. Its pharmacological treatment consists of intravenous saline hydration, loop diuretic and intravenous administration of bisphosphonates. However, data evaluating these treatments are very limited.

The aim of this study was to assess the efficiency of saline hydration, furosemide, and bisphosphonates in the management of severe hypercalcemia secondary to a primary hyperparathyroidism (PHPT).

Methods: We conducted a retrospective analysis in 50 patients with severe hypercalcemia (≥ 120 mg/l) secondary to a PHPT. Clinical, biological and treatment data were collected regularly. The efficiency of each therapeutic agent was evaluated according to the variation of calcium levelcalculated as: Δ calcium = Baseline calcium level –minimal calcium level after the administration of each agent.

Results: The study population included 41 women and 9 men with a mean age of 58.9 ± 12.9 years. At baseline, they had a mean serum calcium level of 133.2 ± 14.5 mg/l [extremes: 120–180] and a mean parathormone level of 682.4 ± 600.9 ng/l. Acute renal failure was diagnosed in 15 patients (30%). Thirty six patients received normal saline hydration alone with a mean duration of 5.9 ± 1.1 days with an infusion of 3-4 liters/24 h. The calcium level decreased to 120.1 ± 13.1 mg/l (P < 10^-3) with a Δ calcium of 13.1 ± 14.5 mg/l. Normalization of calcium level occurred in only one patient (3%). Furosemide was prescribed in 36 patients with a mean dose of 60 mg/day [extremes: 20–120]. It resulted in a calcium decline of 12.1 ± 11.3 mg/l (before: 132.5 ± 15.1 mg/l, after: 120.4 ± 9.3 mg/l, P < 10^-3). Normalization of calcium level occurred in only one patient (3%). Twenty one patients received intravenous bisphosphonates. The mean maximal reduction in serum calcium level was 24.2 ± 8.9 mg/l [extremes: 6–44] reached 5.2 ± 3.2 days after the administration of bisphosphonates (before: 132.1 ± 8.8 mg/l, after: 107.85 ± 9.75 mg/l, P <10^-3). Normalization of calcium level occurred in 8 patients (38%).

Serum creatinine level significantly decreased in all patients (P < 10^-3).

Conclusion: Our results demonstrated the absence of a significant additional effect of furosemide on calcium level in patient with severe hypercalcemia as compared to the effect of saline hydration alone. However, bisphosphonates were more potent. Thus, appropriate normal saline hydration and immediate intravenous bisphosphonates infusion should be considered in the pharmacological management of severe hypercalcemia in patients with PHPT.