Abstract: SA-PO1191
Urinary Leak Mimicking Acute Rejection in the Early Post-Kidney Transplant Period
Session Information
- Transplantation: Clinical - Complications, Pediatrics, and Multi-Organ Considerations
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 2002 Transplantation: Clinical
Author
- Jayaprakash Narayanan, Miruthu Varshini, Saint Clare's Health System, Denville, New Jersey, United States
Introduction
Acute kidney injury after renal transplantation is commonly attributed to rejection, calcineurin inhibitor toxicity, delayed graft function, or infection. Urinary leak is an uncommon surgical complication that may mimic rejection. We report early post-transplant AKI caused by peri-anastomotic urinoma presenting as graft dysfunction.
Case Description
A 32-year-old man with ESRD secondary to IgA nephropathy underwent living donor renal transplantation with an initially uncomplicated postoperative course. Creatinine improved from 1.8 mg/dL on postoperative day (POD) 1 to 1.0 mg/dL by POD 8.
He presented on POD 15 with creatinine rising to 1.8 mg/dL without oliguria, graft tenderness, or hemodynamic instability. Urine culture grew Klebsiella pneumoniae (>10^5 CFU/mL), and imipenem-cilastatin was initiated. Tacrolimus levels remained therapeutic.
Despite antibiotics, creatinine increased to 2.2 mg/dL by POD 17. Doppler ultrasonography demonstrated preserved graft perfusion with peri-vesical fluid collection near the ureteroneocystostomy. Pelvic MRI demonstrated a 6.9 × 4.0 cm peri-anastomotic collection causing mild hydronephrosis with extrinsic compression of the pelviureteric junction concerning for urinoma.
Percutaneous drainage yielded 90 mL of serous fluid with fluid creatinine higher than serum creatinine, confirming urinoma. Renal function improved following drainage, with creatinine decreasing to 1.1 mg/dL, avoiding unnecessary allograft biopsy or escalation of immunosuppression.
Discussion
Urinary leak is an important cause of early post-transplant AKI and commonly occurs at the ureteroneocystostomy site. Presentation may be subtle despite graft dysfunction. This case highlights the challenge of differentiating urinary leak from acute rejection in patients with preserved urine output. MRI characterized the peri-anastomotic collection, while fluid creatinine confirmed the diagnosis. Prompt drainage improved graft function and avoided unnecessary intervention.