title: Severe resistant hypocalcemia in multiple myeloma after zoledronic acid administration: a case report.
abstract: BACKGROUND
  Hypercalcemia is one of the most common metabolic abnormalities encountered in any form of malignancy. Hypocalcemia, however, is a rare manifestation, especially in cancers with bone involvement. Here we present a case of hypocalcemia in a patient with multiple myeloma that was refractory to treatment.
  
  
  METHODS
  A 73-year-old African American woman recently diagnosed with multiple myeloma, presented with a 2-day history of fever, vomiting and hypocalcemia. Ten days prior to admission she received zoledronic acid, Velcade® (bortezomib), Revlimid® (lenalidomide) and dexamethasone. Treatment was started with intravenous antibiotics and calcium gluconate boluses. After 24 hours of treatment her calcium level became undetectable (<5mg/dL). Continuous intravenous calcium gluconate infusions in addition to boluses were started. She remained persistently hypocalcemic and eventually developed tonic-clonic seizures. Vitamin D levels were found to be low and intravenous paricalcitol was initiated, which improved her calcium level.
  
  
  CONCLUSIONS
  Underlying vitamin D deficiency can precipitate severe hypocalcemia in patients with multiple myeloma receiving bisphosphonates. This warrants baseline screening for vitamin D deficiency in these patients.
authors.affiliation: UAB Health Center Montgomery, 2055 East South Boulevard, Suite 202, Montgomery, AL 36116, USA. adrianaldave@uabmc.edu.
authors.forename: Adrian P
authors.initials: AP
authors.lastname: Noriega Aldave
authors.forename: Shikha
authors.initials: S
authors.lastname: Jaiswal
mesh_terms: D000368:Aged; D050071:Bone Density Conservation Agents / Q000009:adverse effects*; D004164:Diphosphonates / Q000009:adverse effects*; D005260:Female; D006801:Humans; D006996:Hypocalcemia / Q000139:chemically induced* / Q000000981:diagnostic imaging; D007093:Imidazoles / Q000009:adverse effects*; D009101:Multiple Myeloma / Q000000981:diagnostic imaging / Q000188:drug therapy*; D014057:Tomography, X-Ray Computed; D014808:Vitamin D Deficiency / Q000150:complications*; D000077211:Zoledronic Acid
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid