title: Changes in bone matrix mineralization after growth hormone treatment in children and adolescents with chronic kidney failure treated by dialysis: a paired biopsy study.
abstract: BACKGROUND
  Patients with chronic kidney disease (CKD) develop renal osteodystrophy with alterations in bone turnover, mineralization, and volume (TMV). A specific skeletal complication in children is growth impairment, which currently is treated by recombinant human growth hormone (rhGH). The effects on bone material properties are poorly understood. This study assesses the effects of rhGH treatment on bone matrix mineralization.
  
  
  METHODS
  Observational study.
  
  
  METHODS
  18 short children and adolescents (aged 3.6-16 years) with CKD on dialysis therapy.
  
  
  METHODS
  rhGH treatment for 1 year.
  
  
  RESULTS
  Tetracycline-labeled bone biopsy classified according to the TMV system.
  
  
  METHODS
  Bone mineralization density distribution (BMDD) was evaluated by quantitative backscattered electron imaging in trabecular and cortical compartments. Additional data for patients' height and biochemical bone serum parameters were obtained.
  
  
  RESULTS
  Prior to rhGH treatment, our cohort showed low bone turnover and high mineralization densities versus reference data: Ca(mean) (weighted mean calcium content) in cancellous bone, +3.3% (P = 0.04); Ca(mean) in cortical bone, +6.7% (P < 0.001); Ca(peak) (mode of the BMDD) in cancellous bone, +5.0% (P < 0.001); Ca(peak) in cortical bone, +8.2% (P < 0.001); Ca(width) (heterogeneity in mineralization), no significant difference for cancellous (P = 0.2) and cortical (P = 0.1) bone; Ca(high) (portion of fully mineralized bone) in cancellous bone, 5-fold greater (P < 0.001); Ca(high) in cortical bone, 14-fold greater (P < 0.001); Ca(low) (portion of low mineralized bone) in cancellous bone, +23.9% (P = 0.02); Ca(low) in cortical bone, -22.2% (P = 0.05). After rhGH treatment, height increased by 9.1 cm (P < 0.001) and bone turnover indices to normal values or beyond. Matrix mineralization was lesser and more heterogeneous compared to baseline: Ca(width) for cancellous bone, +15.3% (P < 0.001); Ca(width) for cortical bone, +34.1% (P < 0.001). Ca(mean), Ca(peak), and Ca(high) for cancellous bone and Ca(mean) and Ca(peak) for cortical bone were no longer significantly different from reference data. Ca(high) for cortical bone dramatically decreased after treatment but was still substantially greater than reference data.
  
  
  CONCLUSIONS
  Low case number per TMV subgroup, no measurements of fibroblast growth factor 23.
  
  
  CONCLUSIONS
  Children and adolescents with CKD and growth deficiency are at risk of having low bone turnover. rhGH treatment improves height and concomitantly bone modeling/remodeling, which appears beneficial for bone matrix mineralization.
authors: Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria.
authors: Kamilla
authors: K
authors: Nawrot-Wawrzyniak
authors: Barbara M
authors: BM
authors: Misof
authors: Paul
authors: P
authors: Roschger
authors: Małgorzata
authors: M
authors: Pańczyk-Tomaszewska
authors: Helena
authors: H
authors: Ziółkowska
authors: Klaus
authors: K
authors: Klaushofer
authors: Nadja
authors: N
authors: Fratzl-Zelman
mesh_terms: D000293:Adolescent; D001706:Biopsy / Q000379:methods*; D015519:Bone Density; D001857:Bone Matrix / Q000187:drug effects / Q000378:metabolism*; D002114:Calcinosis / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D019382:Human Growth Hormone / Q000627:therapeutic use*; D006801:Humans; D007668:Kidney / Q000378:metabolism / Q000473:pathology*; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000473:pathology / Q000628:therapy; D008297:Male; D006435:Renal Dialysis / Q000009:adverse effects / Q000379:methods*
chemical_list: D019382:Human Growth Hormone