Bone turnover biomarkers and semi-quantitative bone histomorphometry in chronic kidney disease: Comparison between patients with and without fractures

Abstract

Background Chronic kidney disease (CKD) is associated with increased fracture risk not fully explained by reduced bone mineral density. CKD–mineral and bone disorder (CKD-MBD), involving abnormalities in bone turnover, mineralization, and microarchitecture, contributes to skeletal fragility. However, the relationship between routine biochemical markers and semi-quantitative bone histomorphometry remains inadequately defined, particularly in resource-limited settings and the Indian population. The objective of this study was to compare biochemical markers and semi-quantitative bone histomorphometric findings in CKD patients with and without fractures. Methods In this hospital-based comparative cross-sectional study, 48 patients with CKD stage 3–4 were divided into fracture (n = 24) and non-fracture groups (n = 24). Serum calcium, 25-hydroxyvitamin D, parathyroid hormone (PTH), and alkaline phosphatase (ALP) were measured. Bone samples were obtained intraoperatively or via transiliac crest biopsy. Semi-quantitative bone histomorphometry was assessed by a pathologist. Statistical analysis included appropriate group comparisons. Results Fracture patients had significantly lower vitamin D (p = 0.007) and calcium (p = 0.005), and higher PTH (p = 0.002) and ALP (p = 0.001). Semi-quantitative histomorphometric evaluation showed increased osteoid volume, reduced trabecular thickness, and elevated osteoblastic and osteoclastic activity. Conclusion In our study cohort, CKD patients with fractures exhibited a high-turnover bone phenotype with increased osteoid volume and altered bone histology. Biochemical markers may serve as cost-effective adjuncts for fracture risk stratification, particularly where advanced diagnostics are limited. Findings should be interpreted cautiously given the cross-sectional design and small sample size.