title: Pediatric intestinal failure: Predictors of metabolic bone disease.
abstract: OBJECTIVE
  The purpose of this study was to identify risk factors for the development of metabolic bone disease (MBD) in pediatric intestinal failure (IF).
  
  
  METHODS
  A retrospective single-center study of 36 pediatric IF patients who were screened for MBD was performed. Bone mineral density (BMD) was measured using dual-energy X-ray absorptiometry (DXA). Simple regression analysis was initially performed to screen predictors, followed by multivariate step-wise linear regression analysis to identify risk factors of MBD.
  
  
  RESULTS
  Mean lumbar spine BMD Z-score was -1.16 ± 1.32, and 50.0% of patients had a BMD Z-score less than -1.0. Deficiency of 25-hydroxyvitamin-D (25-OHD <30 ng/ml) was present in the 63.8% of patients, while 25.0% had hyperparathyroidism (intact parathyroid hormone (PTH)>55 pg/ml). Seven patients (19.4%) had bone pain, of which 4 (11.1%) suffered a pathologic fracture. Using multivariate analysis, parenteral nutrition (PN) duration predicted decreased BMD (B=-0.132, p=0.006). Serum 25-OHD nonsignificantly correlated with BMD Z-score (B=0.024, p=0.092). Interestingly, repeat DXA after increasing vitamin D supplementation showed no improvement in BMD Z-score (-1.18 ± 1.49 vs -1.36 ± 1.47, p=0.199).
  
  
  CONCLUSIONS
  Pediatric IF is associated with a significant risk of MBD, which is predicted by the duration of PN-dependence. These findings underscore the importance of BMD monitoring. Better therapies for treating IF-associated MBD are needed.
authors.affiliation: Department of Surgery, Section of Pediatric Surgery, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Farokh R
authors.initials: FR
authors.lastname: Demehri
authors.affiliation: Department of Surgery, Section of Pediatric Surgery, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Siddartha
authors.initials: S
authors.lastname: Simha
authors.affiliation: Department of Surgery, Section of Pediatric Surgery, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Lauren
authors.initials: L
authors.lastname: Stephens
authors.affiliation: Clinical Nutrition, C.S. Mott Children's Hospital, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Mary B
authors.initials: MB
authors.lastname: Harris
authors.affiliation: Department of Surgery, Section of Pediatric Surgery, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Meghan A
authors.initials: MA
authors.lastname: Arnold
authors.affiliation: Department of Pediatrics, Division of Pediatric Gastroenterology, University of Michigan Health System, Ann Arbor, MI.
authors.forename: Pamela I
authors.initials: PI
authors.lastname: Brown
authors.affiliation: Department of Surgery, Section of Pediatric Surgery, University of Michigan Health System, Ann Arbor, MI. Electronic address: dttlbm@umich.edu.
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Teitelbaum
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D015519:Bone Density; D001851:Bone Diseases, Metabolic / Q000209:etiology*; D002648:Child; D005260:Female; D006801:Humans; D006961:Hyperparathyroidism / Q000209:etiology; D008159:Lumbar Vertebrae / Q000502:physiology; D008297:Male; D010288:Parenteral Nutrition; D012044:Regression Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D012778:Short Bowel Syndrome / Q000150:complications* / Q000628:therapy; D014808:Vitamin D Deficiency / Q000209:etiology
keywords: Intestinal failure; Metabolic bone disease; Parenteral nutrition; Pediatric; Short bowel syndrome