Assessment of trabecular and cortical parameters using high-resolution peripheral quantitative computed tomography, histomorphometry and microCT of iliac crest bone core in hemodialysis patients.

ABSTRACT

Patients with end-stage renal disease develop changes in bone quality and quantity, which can be assessed using different methods. This study aimed to compare and to correlate bone parameters obtained in vivo using high-resolution peripheral quantitative computed tomography (HR-pQCT) with those obtained by bone biopsy using histomorphometry and microcomputed tomography (microCT) analysis of the iliac crest core, and to evaluate if HR-pQCT is helpful in aiding with categorization of those with high turnover. Twenty hemodialysis patients, 13 females (7 postmenopausal), underwent bone biopsy from 2018 to 2020. The mean age was 48.5 ± 10.6 years, and the mean hemodialysis vintage was 15 years. Histomorphometry identified mineralization defects, low turnover, and high turnover in 65%, 45%, and 35% of the patients, respectively. The highest values of trabecular bone volume (BV/TV) were obtained by histomorphometry, while the highest values of cortical thickness (Ct.Th) were obtained by HR-pQCT at the distal tibia. Moderate correlations were found between BV/TV values obtained by microCT of the bone core and HR-pQCT at the distal radius (r = 0.531, p = 0.016) and at the distal tibia (r = 0.536, p = 0.015). BV/TV values obtained from the bone core by histomorphometry and microCT were also significantly correlated (r = 0.475, p = 0.04). Regarding Ct.Th, there was a strong correlation between the radius and tibia HR-pQCT (r = 0.800, p < 0.001), between bone core microCT and the distal radius HR-pQCT (r = 0.610, p < 0.01), as between histomorphometry and microCT (r = 0.899, p < 0.01). In groups classified by bone turnover, patients with high turnover presented lower BV/TV, Tb.N, Tb.Th, and Ct.Th than those with low turnover in peripheral sites using HR-pQCT. By this method, it was possible to identify low turnover from tibia BV/TV > 12,4% plus Tb.Sp ≤ 0.667 mm (AUC 0.810, 95% CI 0.575 to 0.948) and high turnover from total bone mineral density (BMD) ≤ 154.2 mg HA/cm3 (AUC 0.860, 95% CI 0.633 to 0.982, p < 0.001) and cortical BMD ≤ 691.6 mg HA/cm3 (AUC 0.840, 95% CI 0.609 to 0.963, p < 0.001). In conclusion, HR-pQCT had significant correlation with iliac crest bone in BV/TV and Ct.Th, which are known to provide bone strength. This method is quick and non-invasive and may be helpful in categorizing those with high versus low turnover in hemodialysis patients.