Bone status in cystic fibrosis

M Sood1, G Hambleton, M Super

  • 1The Cystic Fibrosis Unit, Royal Manchester Children's Hospital, Hospital Road, Manchester M27 4HA, UK.

Insights

Children with cystic fibrosis (CF) show normal bone mineral density overall, but reduced bone mineral apparent density (BMAD) at the lumbar spine, indicating potential cortical thinning. This suggests bone health monitoring is crucial even in mild CF cases.

Area of Science:

  • Pediatric Endocrinology
  • Bone Metabolism
  • Cystic Fibrosis Research

Background:

  • Cystic Fibrosis (CF) is a genetic disorder affecting multiple organs, including bones.
  • Bone mineral status in children with CF requires further investigation, particularly in those with milder disease phenotypes.

Purpose of the Study:

  • To assess the bone mineral status in children diagnosed with cystic fibrosis.
  • To compare bone parameters between CF patients and age- and sex-matched healthy controls.

Main Methods:

  • Dual-energy X-ray absorptiometry (DXA) was used to measure bone mineral content (BMC), bone area (BA), and areal bone mineral density (BMD).
  • Quantitative computed tomography (QCT) assessed vertebral trabecular bone mineral density (vTBMD), and quantitative ultrasound (QUS) measured calcaneal broadband ultrasound attenuation (BUA).
  • Bone mineral apparent density (BMAD) was calculated to assess volumetric density, and disease severity was evaluated using the Shwachman-Kulczycki (SK) score.

Main Results:

  • No significant differences were observed in BUA, whole body/regional BA, adjusted BMC, or areal BMD between CF children and controls.
  • CF patients exhibited reduced lumbar spine bone mineral apparent density (BMAD) compared to controls.
  • Vertebral trabecular bone mineral density (vTBMD) standard deviation scores were significantly higher in CF patients, despite a relatively mild disease severity (median SK score 81).

Conclusions:

  • The findings suggest potential reductions in vertebral cortical thickness or density in CF subjects, indicated by normal vertebral BMC but decreased BMAD.
  • Overall bone mineral status in children with mild CF is comparable to size-matched controls.
  • These results highlight the importance of evaluating volumetric bone density measures in pediatric CF populations.
Abstract

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