IGOR DENIZARDE BACELAR MARQUES
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- EVALUATION OF BONE MICROARCHITECTURE BY HIGH-RESOLUTION PERIPHERAL QUANTITATIVE COMPUTED TOMOGRAPHY IN PATIENTS WITH CHRONIC KIDNEY DISEASE: COMPARISON WITH TRANSILIAC BONE BIOPSY(2015) MARQUES, Igor; ARAUJO, Maria Julia; GRACIOLLI, Fabiana; REIS, Luciene dos; CUSTODIO, Melani; PEREIRA, Rosa; JAMAL, Sophie; JORGETTI, Vanda; DAVID-NETO, Elias; MOYSES, Rosa
- A Randomized Trial of Zoledronic Acid to Prevent Bone Loss in the First Year after Kidney Transplantation(2019) MARQUES, Igor Denizarde Bacelar; ARAUJO, Maria Julia Correia Lima Nepomuceno; GRACIOLLI, Fabiana Giorgetti; REIS, Luciene Machado dos; PEREIRA, Rosa Maria R.; ALVARENGA, Jackeline C.; CUSTODIO, Melani Ribeiro; JORGETTI, Vanda; ELIAS, Rosilene Motta; MOYSES, Rosa Maria Affonso; DAVID-NETO, EliasBackground Bone and mineral disorders commonly affect kidney transplant (KTx) recipients and have been associated with a high risk of fracture. Bisphosphonates may prevent or treat bone loss in such patients, but there is concern that these drugs might induce adynamic bone disease (ABD). Methods In an open label, randomized trial to assess the safety and efficacy of zoledronate for preventing bone loss in the first year after kidney transplant, we randomized 34 patients before transplant to receive zoledronate or no treatment. We used dual-energy x-ray absorptiometry (DXA), high-resolution peripheral quantitative computed tomography (HR-pQCT), and bone biopsies to evaluate changes in bone in the 32 evaluable participants between the time of KTx and 12 months post-transplant. Results Both groups of patients experienced decreased bone turnover after KTx, but zoledronate itself did not affect this outcome. Unlike previous studies, DXA showed no post-transplant bone loss in either group; we instead observed an increase of bone mineral density in both lumbar spine and total hip sites, with a significant positive effect of zoledronate. However, bone biopsies showed post-transplant impairment of trabecular connectivity (and no benefit from zoledronate); HR-pQCT detected trabecular bone loss at the peripheral skeleton, which zoledronate partially attenuated. Conclusions Current immunosuppressive regimens do not contribute to post-transplant central skeleton trabecular bone loss, and zoledronate does not induce ABD. Because fractures in transplant recipients are most commonly peripheral fractures, clinicians should consider bisphosphonate use in patients at high fracture risk who have evidence of significantly low bone mass at these sites at the time of KTx.
- Comparison of serum levels with bone content and gene expression indicate a contradictory effect of kidney transplantation on sclerostin(2019) ARAUJO, Maria Julia Correia Lima Nepomuceno; MARQUES, Igor Denizarde Bacelar; GRACIOLLI, Fabiana Giorgetti; FUKUHARA, Luzia; REIS, Luciene Machado dos; CUSTODIO, Melani; JORGETTI, Vanda; ELIAS, Rosilene Mota; DAVID-NETO, Elias; MOYSES, Rosa M. A.In an attempt to clarify the mechanisms of post-transplant bone disease we investigated the bone content and gene expression of several bone-related proteins. After a successful kidney transplant, the content of sclerostin in bone biopsies was found to be increased as measured by immunohistochemistry, multiplex assay, and gene expression despite a concomitant decrease of sclerostin in the serum. The phosphorylation of beta-catenin was increased, confirming Wnt pathway inhibition, an effect accompanied by an increase of the receptor activator of nuclear factor kappa-B ligand (RANKL) and a decrease of osteoprotegerin protein levels in both serum and bone. Thus, changes in circulating biomarkers after kidney transplantation cannot be easily extrapolated to concomitant changes occurring in the bone. Hence, overall treatment decisions post kidney transplant should not be based on serum biochemistry alone.
- Biopsy vs. peripheral computed tomography to assess bone disease in CKD patients on dialysis: differences and similarities(2017) MARQUES, I. D. B.; ARAUJO, M. J. C. L. N.; GRACIOLLI, F. G.; REIS, L. M. dos; PEREIRA, R. M.; CUSTODIO, M. R.; JORGETTI, V.; ELIAS, R. M.; DAVID-NETO, E.; MOYSES, R. M. A.Results from bone biopsy and high-resolution peripheral quantitative computed tomography (HR-pQCT) were compared in 31 CKD patients. There was an agreement mainly for cortical compartment that may represent a perspective on the fracture risk assessment. HR-pQCT also provided some clues on the turnover status, which warrants further studies. Chronic kidney disease (CKD) patients are at high risk of bone disease. Although bone biopsy is considered the best method to evaluate bone disease, it is expensive and not always available. Here we have compared, for the first time, data obtained from bone biopsy and HR-pQCT in a sample of CKD patients on dialysis. HR-pQCT and dual-energy X-ray absorptiometry (DXA) were performed in 31 CKD patients (30 on dialysis). Biopsies were analyzed by quantitative histomorphometry, and classified according to TMV. We have found an inverse correlation between radius cortical density measured by HR-pQCT, with serum, as well as histomorphometric bone remodeling markers. Trabecular density and BV/TV measured through HR-pQCT in the distal radius correlated with trabecular and mineralized trabecular bone volume. Trabecular number, separation, and thickness obtained from HR-pQCT and from bone biopsy correlated with each other. Patients with cortical porosity on bone histomorphometry presented lower cortical density at the distal radius. Cortical density at radius was higher while bone alkaline phosphatase was lower in patients with low turnover. Combined, these parameters could identify the turnover status better than individually. There was an agreement between HR-pQCT and bone biopsy parameters, particularly in cortical compartment, which may point to a new perspective on the fracture risk assessment for CKD patients. Besides classical bone resorption markers, HR-pQCT provided some clues on the turnover status by measurements of cortical density at radius, although the significance of this finding warrants further studies.