PT - JOURNAL ARTICLE AU - Abdul Moiz AU - Tariq Javed AU - Jorge Garces AU - Adriana Dornelles AU - Catherine Staffeld-Coit TI - Posttransplant Nephrocalcinosis Is Associated with Poor Renal Allograft Function: A Single-Center Experience DP - 2015 Mar 20 TA - Ochsner Journal PG - 25--29 VI - 15 IP - 1 4099 - http://www.ochsnerjournal.org/content/15/1/25.short 4100 - http://www.ochsnerjournal.org/content/15/1/25.full SO - Ochsner J2015 Mar 20; 15 AB - Background Nephrocalcinosis, characterized by intratubular and/or parenchymal deposition of calcium phosphate and calcium oxalate crystals, is frequently seen in renal allograft biopsies; however, the clinical consequence of this histologic finding remains unknown. Kidney transplant recipients with good allograft function usually demonstrate improvement in biochemical parameters; however, persistent hyperparathyroidism remains prevalent in this population of patients. We identified renal allografts with nephrocalcinosis and evaluated the effects on renal allograft function and survival.Methods We conducted a single-center, retrospective review of kidney allograft biopsies performed at our center from December 1, 2006 to November 30, 2012. Biopsies with nephrocalcinosis as the primary diagnosis were included in the final analysis. Biochemical parameters at the time of biopsy included serum creatinine, phosphate, calcium, intact parathyroid hormone (iPTH), 25-hydroxy vitamin D, and albumin. Serum creatinine was measured at 1, 3, 6, and 12 months after nephrocalcinosis was diagnosed. The use of calcimimetics, vitamin D analogs, active vitamin D, and bisphosphonates was also reviewed.Results We identified 12 patients with nephrocalcinosis as the primary diagnosis on renal biopsy. The average age of these patients was 52.2 ± 11.9 years, and the average time since transplantation was 2.3 ± 2.7 years. The baseline serum creatinine was 1.37 ± 0.4 mg/dL before the onset of acute kidney injury (AKI). Mean iPTH and 25-hydroxy vitamin D at the time of AKI were 495.66 ± 358.9 pg/mL and 19.9 ± 13.3 ng/mL, respectively. Renal function deteriorated in all patients, and mean serum creatinine at 12-month follow up was 2.37 ± 1.3 mg/dL (P=0.028). One patient progressed to end-stage renal disease at the end of the study period.Conclusion The histologic finding of nephrocalcinosis is associated with poor renal allograft function. Metabolic abnormalities including hyperparathyroidism persist in renal allograft recipients despite normal allograft function and may be associated with the development of nephrocalcinosis in renal transplant recipients.