Schmucker Abigail M, Green Dina E, Montemuro Philip M
Sidney Kimmel Medical College, Thomas Jefferson University, 1025 Walnut Street, Philadelphia, PA 19107, USA.
Lankenau Medical Center, 100 East Lancaster Avenue, Wynnewood, PA 19096, USA.
Case Rep Endocrinol. 2020 Jul 23;2020:8833723. doi: 10.1155/2020/8833723. eCollection 2020.
Hypocalcemia is a known risk following bariatric surgery and can contribute to the development of osteoporosis. Osteoporosis is commonly treated with denosumab, though denosumab can exacerbate underlying abnormalities in calcium homeostasis. We present the case of a 59-year-old female with severe hypocalcemia who had been treated with denosumab for osteoporosis three months before and had Billroth II gastric bypass surgery 15 years before, for bariatric purposes. Intravenous calcium supplementation was used to correct the initial electrolyte abnormality, and the patient was able to maintain appropriate calcium levels on high doses of oral calcium before discharge. Denosumab-induced hypocalcemia has been previously reported in patients with predisposing conditions including chronic kidney disease, primary sclerosing cholangitis, Crohn's disease, and a history of sleeve gastrectomy for marginal gastric ulcers. A few cases of hypocalcemia have been reported in patients with a history of bariatric surgery secondary to vitamin D deficiency, but this report is unique in demonstrating denosumab-induced hypocalcemia after bariatric surgery with normal vitamin D levels, suggesting a primary malabsorption of calcium. The risk of severe hypocalcemia should be considered before initiating denosumab to treat osteoporosis in patients with a history of bariatric surgery. If denosumab is initiated, serum calcium levels should be closely monitored, and patients should be educated about the importance of adherence to calcium supplementation.
低钙血症是减肥手术后已知的风险，可导致骨质疏松症的发生。骨质疏松症通常用狄诺塞麦治疗，尽管狄诺塞麦会加剧钙稳态的潜在异常。我们报告一例59岁女性，患有严重低钙血症，她在三个月前因骨质疏松症接受了狄诺塞麦治疗，15年前因减肥目的接受了毕罗Ⅱ式胃旁路手术。静脉补钙用于纠正最初的电解质异常，患者在出院前能够通过高剂量口服钙剂维持适当的钙水平。先前已有报道，在患有包括慢性肾病、原发性硬化性胆管炎、克罗恩病以及因边缘性胃溃疡行袖状胃切除术病史等易感疾病的患者中，会发生狄诺塞麦诱导的低钙血症。有几例减肥手术史的患者因维生素D缺乏继发低钙血症的病例报告，但本报告的独特之处在于，展示了减肥手术后维生素D水平正常情况下发生的狄诺塞麦诱导的低钙血症，提示存在原发性钙吸收不良。对于有减肥手术史的患者，在开始使用狄诺塞麦治疗骨质疏松症之前，应考虑严重低钙血症的风险。如果开始使用狄诺塞麦，应密切监测血清钙水平，并应对患者进行关于坚持补钙重要性的教育。
