Abstract: TH-PO155
Bone Histomorphometry in Patients with CKD Stage 2-5ND with or without Bone Loss Defined by Bone Densitometry
Session Information
- CKD-MBD: Clinical
October 24, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Bone and Mineral Metabolism
- 502 Bone and Mineral Metabolism: Clinical
Authors
- Alves, Karla Maria, Universidade Federal de Sao Paulo, São Paulo, SP, Brazil
- Barreto, Fellype, Universidade Federal do Parana, Curitiba, PR, Brazil
- Santos, Cássia Gomes da Silveira, Universidade Federal do Parana, Curitiba, PR, Brazil
- Canziani, Maria Eugenia F., Universidade Federal de Sao Paulo, São Paulo, SP, Brazil
- Carvalho, Aluizio B., Universidade Federal de Sao Paulo, São Paulo, SP, Brazil
Background
Bone biopsy followed by histomorphometry is the gold standard for diagnosing renal osteodystrophy. New evidence has shown that bone mass loss, diagnosed by bone densitometry (DXA), could estimate the fracture risk in patients with CKD stages 3a-5D. However, there is no consensus on the relationship between DXA and bone histomorphometry in this population. This study compared bone histomorphometry in patients with CKD 2-5ND who had or did not have DXA-identified bone mass loss.
Methods
This cross-sectional study includes 50 asymptomatic patients with CKD stage 2-5ND, aged 18-70 ys. The exclusion criteria were infectious, inflammatory or neoplastic diseases, use of phosphate binders, vitamin D, corticosteroids, or bisphosphonates. Clinical evaluation included laboratory tests, DXA, and bone biopsy followed by histomorphometric analysis, proposed by ASBMR. Undecalcified bone samples were submitted to histomorphometry using the semiautomatic system Osteomeasure®. Bone mineral density (BMD) by DXA (g/cm2), was measured at the lumbar spine (L1L4) and femoral neck (FN) on the densitometer LUNAR®. Bone loss was defined as a BMD T-score less than -1.0 SD for young subjects.
Results
A total of 50 patients, 52±10 ys, 68% men, 30% diabetics, with eGFR=34±16mL/min/1.73m2 was included. BMD was 1.18±0.19 and 0.93±0.15g/cm2 (L1L4 and FN, respectively). BMD reduction was observed in 40% of patients in L1L4 and FN. Patients with reduced BMD, compared with those without, showed in L1L4 an increased osteoblastic (2.70±2.69 vs 1.24±1.58%;p=0.04), osteoclastic (10.5±6.5 vs 6.0±5.7%;p=0.01), and eroded (1.12±0.78 vs 0.47±0.69%;p<0.01) surfaces, respectively. Moreover, increased fibrosis (0.08±0.1 vs 0.02±0.04%;p=0.02) and bone formation rate (0.035±0.030 vs 0.014±0.015µ3/µ2/d;p<0.01) were observed in patients with reduced BMD. Patients with reduced BMD in FN, compared with those without, showed decreased trabecular bone volume (14.2±4.7 vs 19.1±5.5%;p<0.01) and trabecular number (1.19±0.34 vs 1.51±0.36N/mm;p<0.01), and increased trabecular separation (781.6±251.8 vs 576.1±189.6mm;p<0.01), respectively.
Conclusion
Bone loss in the lumbar spine is associated with mild hyperparathyroid bone disease, while in the femoral neck, it is associated with decreased bone volume and altered bone microarchitecture.
Funding
- Government Support – Non-U.S.