Kidney Allograft Torsion in a Multiorgan Transplant Recipient with ADPKD: A Rare but Twisting Diagnosis

Introduction: Kidney allograft torsion (KAT) is a rare cause of acute graft dysfunction, most commonly reported in intraperitoneal transplants. It typically results from rotation of the allograft around its vascular pedicle, leading to ischemia or graft loss if not recognized. Pediatric patients and those with mobile grafts or large peritoneal spaces are at increased risk. Case Description: A 24-year-old man with ESRD from autosomal dominant polycystic kidney disease (ADPKD) and non-ischemic cardiomyopathy (NICMP) underwent simultaneous orthotopic heart and intraperitoneal kidney transplantation after bilateral nephrectomies. His post-transplant course was complicated by delayed graft function (nadir creatinine 1.7 mg/dL), followed by AKI due to polyomavirus nephropathy (peak creatinine 7.5 mg/dL). The biopsy was complicated by a perinephric hematoma requiring embolization. After conversion from tacrolimus to cyclosporine, kidney function improved and BK viremia decreased. Two weeks later, imaging revealed a 180-degree anterior-posterior flip of the kidney allograft, consistent with torsion. Remarkably, Doppler ultrasound and MRA demonstrated preserved perfusion, and no surgical intervention was required. Discussion: KAT is rare in adults but should be suspected in cases of unexplained AKI, especially in intraperitoneal grafts. Risk factors include lack of adhesions, long pedicles, large peritoneal spaces, and pediatric anatomy. In this case, prior ADPKD with abdominal distension may have created a capacious peritoneal cavity, increasing graft mobility. Additionally, perinephric hematoma post-biopsy may have contributed by destabilizing local tissue planes. While some cases require surgical detorsion or nephropexy, noninvasive vascular imaging can guide management. Conservative monitoring may suffice in hemodynamically stable patients with maintained allograft perfusion.