Safety And Efficacy of Drug Eluting Stents for Treatment of Transplant Renal Artery Stenosis
OBJECTIVE:Transplant renal artery stenosis (TRAS) after renal transplantation is a common cause of graft dysfunction and failure. Endovascular intervention in the form of percutaneous transluminal angioplasty (PTA) and stenting has rapidly become the dominant treatment modality for the TRAS. There is a paucity of clinical data on use of drug-eluting stent (DES) for TRAS. We investigated the outcomes of patients with clinically significant TRAS undergoing DES placement. METHODS:A retrospective review of patients with clinically significant TRAS undergoing PTA with DES placement from June 2014 to April 2021 was conducted. Patients treated for TRAS exhibited uncontrolled hypertension and/or unexplained allograft dysfunction. Patient demographics, procedural details, and follow-up outcomes were collected. Primary endpoints were the in-stent primary patency and graft survival. Secondary endpoints were freedom from reintervention, primary-assisted patency and access-related complications. RESULTS:Thirteen TRAS in twelve patients with graft function alteration were treated with DES. The median age was 57 years (interquartile range (IQR), 48-63 years), and nine (70%) patients were male (Table). The median follow-up was 9 months (IQR, 4-52 months). The most common comorbidity was hypertension (100%), coronary artery disease (83%) and diabetes. The median time from deceased donor transplant to intervention was 5.8 months (IQR, 3.5-6.7 months). TRAS was most commonly found at the juxta-ostial segment (77%). The procedure was performed with carbon dioxide angiography with minimal amount of iodinated contrast (median, 3 mL) under local anesthesia in nine (69%) and general anesthesia in four (31%) patients. The median stent diameter was 4.5 mm (IQR, 4-5 mm), and the median stent length was 15 mm (IQR, 15-18 mm). No intraoperative complications occurred. The rates of stenosis-free primary patency of the DES and graft survival were 76% and 100%, respectively. All three reinterventions for restenosis resulted from the kinking of the transplant renal artery proximal to the DES, which were treated by extending the stent more proximally 1-2 mm into the external iliac artery. There were no access-related complications. The median time to reintervention was 0.9 months (range, 0.23-2 months). Freedom from reintervention and primary-assisted patency were 76% and 100%, respectively. CONCLUSIONS:Our study demonstrates that DES is a safe and effective treatment modality in patients with TRAS at short to mid-term follow-up. As all reinterventions after DES were performed due to kinking of the transplant renal artery proximal to the stent, bridging of the DES 1-2 mm into the external iliac artery is recommended.
Intraoperative Verapamil Fails to Reduce Delayed Graft Function in Donation After Circulatory Death Renal Allografts
Background/UNASSIGNED:The shortage of transplantable organs has led to increased utilization of kidneys that may be particularly vulnerable to ischemia-reperfusion injury (IRI) and delayed graft function (DGF). Kidneys from donation after circulatory death (DCD) donors have additional IRI from donor procurement that results in increased risk of DGF. Verapamil may reduce IRI in kidney allografts when given at the time of organ reperfusion. This study sought to determine if intraoperative administration of verapamil (Ver) could reduce the risk of DGF in DCD kidney transplants. Methods/UNASSIGNED:A single-center retrospective matched cohort study was performed of 93 Ver (-) kidney transplant recipients compared with 93 Ver (+) kidney transplant recipients, matched by donor age, Kidney Donor Profile Index, and DCD status. Covariates that could impact DGF risk were evaluated by univariate and multivariate logistic regression analyses. Results/UNASSIGNED:The Ver (-) and Ver (+) matched cohorts did not have any significant differences in the demographic covariates. There was no difference in DGF rate between the Ver cohorts in either the overall study population or within the DCD subgroup. There was a trend toward reduced DGF in the Ver (+) cohort for cold ischemia time (CIT) â‰¤24â€‰h, but this failed to achieve statistical significance. On multivariate analysis, only CIT was found to be independently associated with DGF. Conclusions/UNASSIGNED:Intraoperative verapamil failed to reduce DGF risk in DCD kidney allografts. Limitations to this study include nonrandomization for the intraoperative administration of verapamil and the mean CIT >24â€‰h in the study population. Only CIT was an independent prognosticator for DGF on multivariate analysis in a cohort matched for DCD status, consistent with prior studies.
Safety And Efficacy Of Drug-eluting Stents For Treatment Of Transplant Renal Artery Stenosis [Meeting Abstract]
INTRODUCTION AND OBJECTIVES: There is a paucity of clinical data on use of drug-eluting stent (DES) for transplant renal artery stenosis (TRAS). Therefore, we investigated outcomes of patients with clinically significant TRAS undergoing DES placement.
METHOD(S): A retrospective review of patients with clinically significant TRAS undergoing percutaneous balloon angioplasty with DES from 2014 to 2021 was conducted. Patient demographics, procedural details, and follow-up outcomes were collected. Primary endpoints were the in-stent primary patency and graft survival. Secondary endpoints were freedom from reintervention and primary-assisted patency RESULTS: Thirteen TRAS in twelve patients with graft function alteration were treated with DES. The median age was 57 years (interquartile range (IQR), 48-63), and nine (75%) were male. The median follow-up was 9 months (IQR, 4-52). The median time from transplant to intervention was 5.8 months. TRAS was most commonly found at the proximal portion (92%). The procedure was performed with carbon dioxide angiography with minimal amount of contrast (median, 3 mL) under local and general anesthesia in nine (69%) and four (21%) TRAS, respectively. The rates of stenosis-free primary patency of the DES and graft survival were 75% and 100%, respectively. Three reinterventions for restenosis resulted from the kinking of the transplant renal artery proximal to the DES, which were treated by extending the stent more proximally into the origin of the transplant renal artery. The median time to reintervention was 0.9 months (range, 0.23-2 months). Freedom from reintervention and primary-assisted patency were 75% and 100%, respectively.
CONCLUSION(S): Despite the lack of evidence in literature, these data demonstrate that DES is safe and effective in treating patients with TRAS at short to midterm. As all reinterventions after DES were performed due to kinking of the transplant renal artery proximal to the stent, bridging of the DES into the external iliac artery is recommended.
Donor-Derived Mucormycosis: A Rare but Devastating Complication after Kidney Transplantation [Meeting Abstract]
Introduction: Mucormycosis can have devastating sequelae after solid-organ transplantation. Case Report:A 23-year-old male with ESRD from lupus underwent pediatric en bloc kidney transplant. The donor was a 2-year old with COD drowning, terminal Cr 3.2 mg/dL, CIT 30 hours. US obtained POD#1 and #3 confirmed patent vasculature. On POD#4, he began to produce urine (~300cc/day). On POD#8, stat US for abdominal pain showed no blood flow in either allograft. The patient was taken immediately to the OR. Intra-operatively, the kidneys were necrotic with thrombosis of the donor IVC and aorta (Figure 1). Meropenem, vancomycin, and micafungin were given for potential donor-derived infection. Notably, the arterial thrombus extended down the recipient EIA. A thrombectomy was performed, and the thrombus was sent for culture and pathology. The next night, he reported thigh pain and was sent for stat CTA. He arrested shortly after the CT scan.and expired. The next day we learned the pediatric liver recipient had thrombosed the hepatic artery and portal vein on POD#5 with subsequent graft failure and death. Explant pathology and autopsy demonstrated diffuse, angioinvasive mucormycosis. We subsequently confirmed mucormycosis in the explanted pediatric en bloc kidneys and the arterial thrombus (Figure 2). Our patient's autopsy was notable for massive bilateral main pulmonary artery emboli.
Conclusion(s): Mucormycosis can be a rare donor-derived infection that is associated with high mortality. Treatment includes prompt diagnosis, antifungal therapy, and surgical debridement
Caregiver exposure to hepatitis C virus following transplantation with hepatitis C viremic donor organs: A case series
INTRODUCTION/BACKGROUND:Direct acting antiviral (DAA) therapeutics have ushered in an era in which transplanting organs from donors infected with hepatitis C virus (HCV+) into recipients without (HCV-) is an increasingly common practice. Rare but potentially life-threatening events have been reported in recipients of HCV+ organs. METHODS:Since 2018 at our institution, 182 HCV- patients have received HCV+ donor organs. Here, we retrospectively reviewed cases in which recipients' family member caregivers reported sustaining needlestick exposures at home following discharge of the transplant recipient from the hospital. RESULTS:Caregiver needlestick exposures were passively reported in three cases of HCV+ into HCV- transplants (1.64% of such cases at our center). In all instances, the exposed individuals were aiding in diabetic management and the exposure occurred via lancets or insulin needles. In one case, the recipient viral load was undetectable at the time of the exposure but in the other two, recipients were viremic, putting their family members at risk to contract HCV infection. Surveillance for the exposed individuals was undertaken and no transmissions occurred. DISCUSSION/CONCLUSIONS:For centers performing HCV+ into HCV- transplants, it is important that informed consent includes discussion of potential secondary risks to family members and caregivers. Further, protocols for post-exposure surveillance and for the acquisition of DAA treatment in the event of a secondary transmission should be in place. This article is protected by copyright. All rights reserved.
Clinical and Financial Implications of 2 Treatment Strategies for Donor-derived Hepatitis C Infections
Transplanting hepatitis C viremic donor organs into hepatitis C virus (HCV)-negative recipients is becoming increasingly common; however, practices for posttransplant direct-acting antiviral (DAA) treatment vary widely. Protracted insurance authorization processes for DAA therapy often lead to treatment delays.
Rare presentation of inflammatory myofibroblastic tumor in a failed renal allograft
Inflammatory myofibroblastic tumors (IMT) are rare, mesenchymal tumors that can occur in any anatomic location. IMTs have a variable clinical course but usually require wide surgical excision to prevent local recurrence. There have been limited case reports of IMT occurring in solid organ transplant recipients. Herein we report on a case of IMT presenting in a failed renal allograft. A 53-year-old male awaiting re-transplant presented with pain and a palpable mass in his allograft. Imaging demonstrated an infiltrative soft tissue mass encasing the renal hilum. Percutaneous biopsy demonstrated a myofibroblastic proliferation with myxoid background and no high-grade features. The tumor cells were diffusely positive for anaplastic lymphoma kinase-1 (ALK-1) and had a Ki-67 proliferation index of 10%. These findings were consistent with a diagnosis of IMT. A transplant nephrectomy was performed with wide margins to achieve an R0 resection. Pathology on the resection specimen confirmed an IMT that measured 6.5 cm x 6.3 cm. The patient has no evidence of local recurrence at 6-months follow-up and has been relisted for a second kidney transplant.
Development of COVID-19 Infection in Transplant Recipients After SARS-CoV-2 Vaccination [Comment]
Impact of the 2014 kidney allocation system changes on trends in A2/A2B into B kidney transplantation and organ procurement organization reporting of donor subtyping
The current kidney allocation system (KAS) preferentially allocates kidneys from blood type A2 or A2B (A/A2B) donors to blood type B candidates. We used national data to evaluate center-level performance of A2/A2B to B transplants, and organ procurement organization (OPO) reporting of type A or AB donor subtyping, in 5-year time periods prior to (2009-2014) and following (2015-2019) KAS implementation. The number of centers performing A2/A2B to B transplants increased from 17 pre-KAS to 76 post-KAS, though this still represents only a minority of centers (7.3% pre-KAS and 32.6% post-KAS). For high-performing centers, the median net increase in A2/A2B to B transplants was 19 cases (range -2-72) per center in the 5 years post-KAS. The median net increase in total B recipient transplants was 21 cases (range -17-119) per center. Despite requirements for performance of subtyping, in 2019 subtyping was reported on only 56.4% of A/AB donors. This translates into potential missed opportunities for B recipients, and even post-KAS up to 2322 A2/A2B donor kidneys may have been allocated for transplantation as A/AB. Further progress must be made both at center and OPO levels to broaden implementation of A2/A2B to B transplants for the benefit of underserved recipients.
Best practice recommendations for the use of hepatitis C viremic donor organs for hepatitis C virus naÃ¯ve recipients
The combination of the transplant organ deficit, the increase in HCV nucleic acid positive donors (HCV NAT+), and the development of direct-acting antiviral agents (DAAs) has resulted in a rapid increase in HCV NAT+ organ transplants into HCV naÃ¯ve recipients. Early clinical experience with HCV NAT+ donor organs has shown promising outcomes; however, best practices are lacking to guide transplant programs during all phases of patient care. Transplant programs developing protocols for the utilization of HCV NAT+ organs will need a multidisciplinary team to address all aspects of pre-transplant and post-transplant patient care. Reports of fibrosing cholestatic hepatitis in HCV NAT+ organ transplant recipients receiving delayed DAA initiation highlight the need for the transplant community to develop safe and effective protocols. A failure to do so will inevitably lead to the erosion of public trust from cases of missed or inadequately treated donor-derived HCV infections. Herein, we provide best practice guidelines for the utilization of HCV NAT+ organs into HCV-negative recipients based on literature review and expert opinion from the faculty of the ASTS Standards and Quality Committee.