title: Bone mineral density and bone acquisition in children and young adults with cystic fibrosis: a follow-up study.
abstract: OBJECTIVE
  To investigate bone mineral density and bone homeostasis in cystic fibrosis (CF) and to assess changes in a 2-year period.
  
  
  METHODS
  Thirty-eight patients with clinically stable CF (11 children, 16 adolescents, 11 young adults) were enrolled. No patient was treated with corticosteroids before or during the study. Weight and height Z scores and bone mineral density (BMD) Z-score at the femoral neck and the lumbar spine were recorded at the beginning of the study and after 2 years. Osteocalcin and cross-link excretion, both measurements of bone turnover were also measured. Correlations between BMD, bone turnover parameters, disease severity, pubertal stage, and nutritional state were calculated. The maternal BMD was also determined and related to that of the child.
  
  
  RESULTS
  Height and weight Z scores were normal in children and below normal in adolescents. Puberty was delayed in most patients. Bone age was lower than chronological age in adolescents. Lumbar spine and femoral neck BMD Z scores were below normal in each age group. Disease severity determined by Schwachman score correlated with lumbar BMD (r = 0.45, P < 0.02). BMD Z scores did not change during 2 year follow-up. Maternal and patient lumbar and femoral BMD correlated significantly (r = 0.51, P < 0.01, and r = 0.54, P < 0.01, respectively).
  
  
  CONCLUSIONS
  Bone deficit is present in patients with CF who have never received steroid treatment. Delay of puberty, chronic inflammation, or genetic susceptibility might be responsible for this phenomenon which was found in patients who had never received steroids and who were in relatively good clinical state.
authors.affiliation: Heim Pál Children's Hospital, Budapest, Hungary.
authors.forename: Rita
authors.initials: R
authors.lastname: Ujhelyi
authors.forename: András
authors.initials: A
authors.lastname: Treszl
authors.forename: Barna
authors.initials: B
authors.lastname: Vásárhelyi
authors.forename: Klára
authors.initials: K
authors.lastname: Holics
authors.forename: Miklós
authors.initials: M
authors.lastname: Tóth
authors.forename: András
authors.initials: A
authors.lastname: Arató
authors.forename: Tivadar
authors.initials: T
authors.lastname: Tulassay
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Tulassay
authors.forename: Miklós
authors.initials: M
authors.lastname: Szathmári
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000293:Adolescent; D000328:Adult; D000365:Age Determination by Skeleton; D001827:Body Height; D001835:Body Weight; D015519:Bone Density / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000235:genetics / Q000503:physiopathology*; D005260:Female; D005272:Femur Neck / Q000000981:diagnostic imaging; D005500:Follow-Up Studies; D006801:Humans; D008159:Lumbar Vertebrae; D008297:Male; D009752:Nutritional Status; D015675:Osteocalcin / Q000097:blood; D012720:Severity of Illness Index; D012741:Sexual Maturation; D013131:Spine / Q000000981:diagnostic imaging
chemical_list: D015675:Osteocalcin