Abstract: TH-PO596
A Rapid Onset of De-Novo Allograft Nephrolithiasis
Session Information
- Trainee Case Reports - II
October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Reports
- 1802 Transplantation: Clinical
Authors
- Maibam, Amita, University of Kentucky, Lexington, Kentucky, United States
- Castellanos, Ana L., University of Kentucky, Lexington, Kentucky, United States
Introduction
De-novo renal allograft nephrolithiasis is a rare condition with incidence of approximately 1 %. Persistent hyperparathyroidism (HPT) after kidney transplant occurs in 15-50% cases but rarely causes renal calculi. Mean duration to diagnosis is 28±22 months. Here we report a case of allograft nephrolithiasis soon after transplantation with underlying tertiary HPT on cinacalcet.
Case Description
A 47-year-old Caucasian male with history of biopsy proven IgA nephropathy, hypertension, ESRD on peritoneal dialysis for 4 years underwent a deceased donor kidney transplant. He received thymoglobulin induction and was started on mycophenolate, tacrolimus, and prednisone for maintenance immunosuppression. After 2 weeks of surgery, cinacalcet was started for hypercalcemia (11 mg/dl). At 6 weeks post transplantation, ureteral J stent was found to be severely encrusted. The stent was removed with subsequent passage of several small stones. Analysis showed 100% brushite stones. A CT stone protocol revealed transplanted kidney with multiple calculi within the collecting system with evidence of obstruction. It was treated with stenting, lithotripsy, and percutaneous nephrostomy placement. Intact parathyroid hormone (iPTH) was 455 pg/ml with serum ionized calcium 6.1 mg/dl and phosphorus of 2.2 mg/dl. Renal function remained stable with serum creatinine of 1.3 mg/dl to 1.4 mg/dl. Patient underwent near-total parathyroidectomy after a nuclear scan showed enlarged parathyroid glands. Histopathology reported hyperplastic glands. One year post parathyroidectomy, there has been no new stone formation with normalization of calcium and iPTH.
Discussion
The most striking aspect of our case was asymptomatic de-novo nephrolithiasis, which presented within 6 weeks after transplantation. It emphasizes the need to remain vigilant of this possible complication during the early post-transplant period in patients with persistent hypercalcemia and HPT. Close monitoring of calcium, phosphorus, and iPTH levels along with necessary imaging can lead to timely diagnosis of this potentially allograft threatening complication. Parathyroidectomy can be performed with excellent outcomes.