title: Hypercalcemia Associated with Calcium Supplement Use: Prevalence and Characteristics in Hospitalized Patients.
abstract: BACKGROUND
  The ingestion of large amounts of milk and antacids to treat peptic ulcer disease was a common cause of hypercalcemia in the past (the "milk-alkali syndrome"). The current popularity of calcium and supplements has given rise to a similar problem.
  
  
  OBJECTIVE
  To evaluate the prevalence and characteristics of hypercalcemia induced by calcium intake ("calcium supplement syndrome"; or CSS) in hospitalized patients.
  
  
  METHODS
  We conducted a retrospective; electronic health record (EHR)-based review of patients with hypercalcemia over a 3-year period. Diagnosis of CSS was based on the presence of hypercalcemia; a normal parathyroid hormone (PTH) level; renal insufficiency; metabolic alkalosis; a history of calcium intake; and documented improvement with treatment.
  
  
  RESULTS
  Of the 72 patients with non-PTH mediated hypercalcemia; 15 (20.8%) satisfied all the criteria for the diagnosis of CSS. Calcium; vitamin D; and multivitamin ingestion were significantly associated with the diagnosis (p values < 0.0001; 0.014; and 0.045 respectively); while the presence of hypertension; diabetes; and renal insufficiency showed a trend towards statistical significance. All patients received intravenous fluids; and six (40%) received calcium-lowering drugs. The calcium level at discharge was normal 12 (80%) of patients. The mean serum creatinine and bicarbonate levels decreased from 2.4 and 35 mg/dL on admission respectively; to 1.6 mg/dL and 25.6 mg/dL at discharge respectively.
  
  
  CONCLUSIONS
  The widespread use of calcium and vitamin D supplementation can manifest as hypercalcemia and worsening of kidney function in susceptible individuals. Awareness among health care professionals can lead to proper patient education regarding these health risks.
authors.affiliation: Division of Endocrinology, University of South Carolina School of Medicine, Columbia, SC 29203, USA. Maria.Machado@uscmed.sc.edu.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Machado
authors.affiliation: University of South Carolina School of Medicine, Columbia, SC 29203, USA. Araba.Bruce-Mensah@uscmed.sc.edu.
authors.forename: Araba
authors.initials: A
authors.lastname: Bruce-Mensah
authors.affiliation: Research Unit, Department of Internal Medicine, University of South Carolina School of Medicine, Columbia, SC 29203, USA. Melanie.Whitmire@uscmed.sc.edu.
authors.forename: Melanie
authors.initials: M
authors.lastname: Whitmire
authors.affiliation: Division of Endocrinology, University of South Carolina School of Medicine, Columbia, SC 29203, USA. Ali.Rizvi@uscmed.sc.edu.|Department of Medicine, University of South Carolina School of Medicine, Columbia, SC 29203, USA. Ali.Rizvi@uscmed.sc.edu.
authors.forename: Ali A
authors.initials: AA
authors.lastname: Rizvi
keywords: calcium; hypercalcemia; milk-alkali syndrome; renal insufficiency