title: Calcium requirements after parathyroidectomy in patients with refractory secondary hyperparathyroidism.
abstract: OBJECTIVE
  Calcium supplements are often required following successful parathyroidectomy (PTX) in order to prevent overt hypocalcemia. The current study aims to quantify these calcium needs and to identify predictors of a high calcium need present at the time of surgery.
  
  
  METHODS
  Charts of 42 patients with chronic kidney disease stage 5D, who underwent a successful subtotal PTX, were reviewed in detail. Biochemical indices of mineral metabolism available within a time frame of 4 weeks before and 6 weeks after the surgery were registered. Details concerning active vitamin D (1-alpha-calcidiol and calcitriol) and calcium supplementation were recorded as well.
  
  
  RESULTS
  Serum calcium, phosphorus and PTH levels declined whereas total alkaline phosphatase levels increased significantly in the early post-PTX period. Transient hypocalcemia was observed in 83% of the patients. The median daily postoperative elemental calcium requirements amounted to 3.2 g during week 1, and declined to 2.4 g during week 6. A high preoperative PTH level and a low serum calcium level were identified as independent predictors of a high postoperative calcium need.
  
  
  CONCLUSIONS
  Substantial amounts of elemental calcium are required following successful subtotal PTX in order to avoid frank hypocalcemia, especially in patients with a high PTH level and a low calcium level before surgery.
authors.affiliation: Department of Medicine, Division of Nephrology, University Hospital Leuven, Leuven, Belgium.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Viaene
authors.forename: Pieter
authors.initials: P
authors.lastname: Evenepoel
authors.forename: Bert
authors.initials: B
authors.lastname: Bammens
authors.forename: Kathleen
authors.initials: K
authors.lastname: Claes
authors.forename: Dirk
authors.initials: D
authors.lastname: Kuypers
authors.forename: Yves
authors.initials: Y
authors.lastname: Vanrenterghem