title: Open-label pilot study comparing quantitative ultrasound and dual-energy X-ray absorptiometry to assess corticosteroid-induced osteoporosis in patients with chronic kidney disease.
abstract: BACKGROUND
  Patients with chronic kidney disease (CKD) might be at high risk for bone disease. Decreased functional kidney mass contributes to renal osteodystrophy, which might be exacerbated by certain drug therapies. Long-term (> or = 6 months) corticosteroid treatment is commonly prescribed in patients with glomerular disease, possibly causing bone loss both indirectly and directly, putting the patient at increased risk for fracture. The dual-energy x-ray absorptiometry (DXA) is the current "gold standard" for measuring osteoporosis-related fractures and works by passing ultrasound waves through bone to determine the structural anisotropy in the heel.
  
  
  OBJECTIVE
  This pilot study was designed to determine whether there is a correlation between DXA and quantitative ultrasound (QUS) in detecting corticosteroid-induced osteoporosis.
  
  
  METHODS
  This open-label pilot study was conducted at the Medical Center Nephrology Clinic, Albany Medical College, Albany, New York. Female patients aged > or = 18 years with a diagnosis of CKD and/or a history of kidney transplantation and who were receiving long-term corticosteroid treatment were enrolled. Each patient served as her own control and underwent DXA of the hip and spine (DXA-hip and DXA-spine, respectively) and QUS of the dominant and nondominant heels (QUS-dominant and QUS-nondominant, respectively), within 1 week so that conditions were similar in each patient.
  
  
  RESULTS
  Eight patients were included in the study (mean [SD] age, 50.2 [11.2] years). A positive correlation was found between DXA-hip and QUS-nondominant (r2=0.76; P=0.009); however, no correlation was found with DXA-spine. Similarly, a positive correlation was found between DXA-hip and QUS-dominant (r2=0.75; P=0.009), but no correlation with DXA-spine was found (r2=0.22).
  
  
  CONCLUSIONS
  In this small, selected population, QUS showed a fair correlation with DXA-hip but no correlation with DXA-spine. Further studies are needed to determine the effectiveness in other populations.
authors: Department of Pharmacy Practice, Albany College of Pharmacy, Albany, New York 12208, USA. grabed@acp.edu
authors: Darren W
authors: DW
authors: Grabe
authors: Marcia
authors: M
authors: Chan
authors: George
authors: G
authors: Eisele