title: Elevated serum parathormone after Roux-en-Y gastric bypass.
abstract: BACKGROUND
  Abnormalities in calcium and vitamin D metabolism are observed early after gastric bypass, whereas clinical or biochemical evidence of metabolic bone disease might not be detected until many years after the procedure. The aim of the present study was to evaluate the impact of bariatric surgery on bone metabolism determined on the basis of postoperative laboratory changes in calcium, phosphorus, magnesium, alkaline phosphatase and parathormone (PTH) levels.
  
  
  METHODS
  110 patients submitted to Roux-en-Y gastric bypass (RYGBP) were followed after surgery, and the following parameters were determined: intact PTH molecule (PTHi; chemiluminescence), alkaline phosphatase (colorimetric method), ionic calcium (selective electrode), phosphorus and magnesium (colorimetric method).
  
  
  RESULTS
  Elevated serum PTHi levels were observed in 29% of the patients and hypocalcemia in 0.9% from the 3rd postoperative month and afterwards (3 to 80 months after surgery).
  
  
  CONCLUSIONS
  There is a need for careful evaluation of bone metabolism and for routine calcium replacement after RYGBP.
authors.affiliation: Serviço de Endocrinologia e Metabologia, Hospital das Clínicas da Universidade Federal de Minas Gerais, Av Alfredo Balena, 30130-100 Belo Horizonte, Minas Gerais, Brazil. mfhsdiniz@ufmg.br
authors.forename: Maria de Fátima Haueisen Sander
authors.initials: Mde F
authors.lastname: Diniz
authors.forename: Marco Túlio Costa
authors.initials: MT
authors.lastname: Diniz
authors.forename: Soraya Rodrigues Almeida
authors.initials: SR
authors.lastname: Sanches
authors.forename: Patrícia Paz Cabral de Almeida
authors.initials: PP
authors.lastname: Salgado
authors.forename: Maristane Mendes Andrade
authors.initials: MM
authors.lastname: Valadão
authors.forename: Flávia Caldeira
authors.initials: FC
authors.lastname: Araújo
authors.forename: Daniele Siríaco
authors.initials: DS
authors.lastname: Martins
authors.forename: Alexandre Lages Savassi
authors.initials: AL
authors.lastname: Rocha
mesh_terms: D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood; D001842:Bone and Bones / Q000378:metabolism*; D002118:Calcium / Q000097:blood; D005260:Female; D015390:Gastric Bypass; D006801:Humans; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D010758:Phosphorus / Q000097:blood; D011184:Postoperative Period
chemical_list: D010281:Parathyroid Hormone; D010758:Phosphorus; D000469:Alkaline Phosphatase; D002118:Calcium