Patients’ clinical and laboratory evaluation
We included 264 patients who underwent renal transplantation and followed in endocrinology and nephrology clinics od Marmara University School of medicine, Kartal Lutfi Kirdar Research and Training Hospital, Bakirkoy Dr. Sadi Konuk Research and Training Hospital, and Dicle University Medical School. All study participants underwent their first transplantation over 12 months, and in this period, graft function was stable. Immune-suppressive treatment was not changed in the last year.
Patients who underwent kidney-pancreas transplantation, patients already on bisphosphonate or denosumab treatment, hyperparathyroidism, or unstable renal function were excluded from the study.
The study protocol was approved by the Marmara University Medical School Ethics Committee (09.2017.518) and conducted following the International Conference on Harmonization Guidelines for Good Clinical Practice and the Declaration of Helsinki.
The induction treatment consisted of 1g of methylprednisolone along with anti-thymocyte globulin or basiliximab, and maintenance therapy included calcineurin inhibitors (tacrolimus or cyclosporine), mammalian target of rapamycin (mTOR) inhibitors (sirolimus or everolimus), anti-proliferative agents (mycophenolate mofetil/ mycophenolic acid or azathioprine) and steroids. After induction, the steroid dose is gradually tapered to 5 mg/day for maintenance.
Clinical characteristics of patients, detailed medical history (duration of hemodialysis, peritoneal dialysis, fracture history, medical history), demographic parameters (age and sex), body mass index, and laboratory data [blood urea nitrogen (BUN), creatinine, calcium, phosphorus, albumin, 25-OH vitamin D, alkaline phosphatase (ALP)], routine lateral thoracal and lumbar Xray images and bone mineral density measurements at the last visit were obtained retrospectively from medical records.
Calcium levels were measured using a photometric color test, phosphorous levels were analyzed using a photometric ultraviolet (UV) test, and ALP and creatinine were analyzed using a kinetic color test (Jaffé method) with an AU5800 Clinical Chemistry Analyzer (Beckman Coulter, USA). Serum PTH was determined in all cases using an immunoassay method (Roche, modular system, E170, Germany). 25-OH vitamin D was analyzed using an immunoassay method on a Unicel DXI 800 automated analyzer (Beckman Coulter, USA).