Development of a checklist framework for kidney transplantation.

Background: Kidney transplantation is the therapy of choice for end-stage kidney disease, and a fast-growing transplant procedure worldwide. Diverse clinical practices for recipients and donors' selection and management between transplant centers hinder the creation and dissemination of an anesthesia-surgical checklist. Methods: Components of the anesthesia-surgical checklist were selected after a review of the English literature using PubMed search for donor, recipient and graft protocols and outcomes of existing practices in the field of kidney transplantation. Key elements of the most relevant articles were combined with our own center's experience and formulated into the proposed checklist. The checklist is intended to be used perioperatively, once patient receives an offer. Results: The perioperative checklist centers primarily on the following donor and recipient's factors: (i) Review of the pretransplant candidate workup; (ii) Assessment of donor/graft status; (iii) Hypothermic machine perfusion parameters; (iv) Operating room management; (v) Sign out. The proposed kidney transplant checklist was designed to ensure consistency and completeness of diverse tasks and facilitates team communication and coordination. Conclusion: We present a novel standardized combined anesthesia-surgical checklist framework for kidney transplant aimed at increasing perioperative safety and streamline the perioperative care of recipients. Future validation studies will determine its clinical feasibility and post-implementation efficacy.

Competing Risks Analysis of Kidney Transplant Waitlist Outcomes: Two Important Statistical Perspectives.

Modern competing risks analysis has 2 primary goals in clinical epidemiology as follows: (i) to maximize the clinician's knowledge of etiologic associations existing between potential predictor variables and various cause-specific outcomes via cause-specific hazard models, and (ii) to maximize the clinician's knowledge of noteworthy differences existing in cause-specific patient risk via cause-specific subdistribution hazard models (cumulative incidence functions [CIFs]). A perfect application exists in analyzing the following 4 distinct outcomes after listing for a deceased donor kidney transplant (DDKT): (i) receiving a DDKT, (ii) receiving a living donor kidney transplant (LDKT), (iii) waitlist removal due to patient mortality or a deteriorating medical condition, and (iv) waitlist removal due to other reasons. It is important to realize that obtaining a complete understanding of subdistribution hazard ratios (HRs) is simply not possible without first having knowledge of the multivariable relationships existing between the potential predictor variables and the cause-specific hazards (perspective #1), because the cause-specific hazards form the "building blocks" of CIFs. In addition, though we believe that a worthy and practical alternative to estimating the median waiting-time-to DDKT is to ask, "what is the conditional probability of the patient receiving a DDKT, given that he or she would not previously experience one of the competing events (known as the cause-specific conditional failure probability)," only an appropriate estimator of this conditional type of cumulative incidence should be used (perspective #2). One suggested estimator, the well-known "one minus Kaplan-Meier" approach (censoring competing events), simply does not represent any probability in the presence of competing risks and will almost always produce biased estimates (thus, it should never be used).

Nocardiosis in Solid Organ Transplant Recipients: 10-Year Single Center Experience and Review of Literature.

Solid organ transplant recipients (SOTRs) are at an increased risk of nocardiosis, a rare but life-threatening opportunistic infection. Universal PCP prophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX) is used at our center, which is active in vitro against most species of the Nocardia genus and may have a role in preventing early infections. This is a single-center retrospective cohort study of nocardiosis in adult SOTRs at a large transplant center between January 2012 and June 2022, with comprehensive review of literature. Out of 6179 consecutive cases, 13 (0.2%) were diagnosed with nocardiosis. The patients were predominantly male (76.9%) and kidney transplant recipients (62%). Infection was diagnosed at median of 8.8 months (range, 3.7-98) after transplant. Patients were followed for a median of 457 days (range 8-3367). Overall mortality within one year after diagnosis was 46% (6/13), of which 17% (1/6) of deaths was attributable to Nocardia infection. No recurrence was reported. Nocardia infections were noted in a small proportion of our SOTRs and carried significant morbidity and mortality. TMP-SMX prophylaxis may be protective in some cases given low incidence of cases.

Optimizing the kidney donor pool: transplanting donor kidneys after partial nephrectomy of masses or cysts.

Background: A limiting factor in expanding the kidney donor pool is donor kidneys with renal tumors or cysts. Partial nephrectomy (PN) to remove these lesions prior to transplantation may help optimize organ usage without recurrence of malignancy or increased risk of complications. Methods: We retrospectively analyzed all recipients of a living or deceased donor graft between February 2009 and October 2022 in which a PN was performed prior to transplant due to the presence of one or more concerning growths. Donor and recipient demographics, perioperative data, donor allograft pathology, and recipient outcomes were obtained. Results: Thirty-six recipients received a graft in which a PN was performed to remove suspicious masses or cysts prior to transplant. Majority of pathologies turned out to be a simple renal cyst (65%), followed by renal cell carcinoma (15%), benign multilocular cystic renal neoplasm (7.5%), angiomyolipoma (5%), benign renal tissue (5%), and papillary adenoma (2.5%). No renal malignancy recurrences were observed during the study period (median follow-up: 67.2 months). Fourteen complications occurred among 11 patients (30.6% overall) during the first 6mo post-transplant. Mean eGFR (± standard error) at 36 months post-transplant was 51.9 ± 4.2 ml/min/1.73 m2 (N = 23). Three death-censored graft losses and four deaths with a functioning graft and were observed. Conclusion: PN of renal grafts with suspicious looking masses or cysts is a safe option to optimize organ usage and decrease the kidney non-use rate, with no observed recurrence of malignancy or increased risk of complications.

Surgical modifications to the conventional kidney transplant technique - the miami transplant institute approach: a retrospective cohort study.

BACKGROUND: At our center, surgical modifications to the conventional kidney transplant technique were developed with two goals in mind: to minimize the risk of developing post-transplant urologic/vascular/other surgical complications, and to simultaneously eliminate the need for initial ureteral stent placement and surgical drainage. METHODS: Here, we describe these modifications along with(what we believe are) their advantages over the conventional technique: creating an abdominal flap for easier abdominal closure(reflecting the parietal peritoneum from the abdominal wall), mobilizing the bladder before transplant(creating more space for bladder dissection, allowing it to move upward during abdominal wall closure), minimizing the dissection of iliac vessels to only anterior lymphatic tissue(attempting to minimize the incidence of fluid collections), using plastic arterial vascular bulldog clamps(causing less trauma to the iliac artery), performing vascular anastomosis of the renal artery first(making it easier for the surgeon to perform this anastomoses), creating longer ureteral spatulation, and inclusion of bladder mucosa along with some detrusor muscle layer in performing the ureteral anastomosis(attempting to minimize the incidence of urologic complications). Of note, no initial ureteral stent placement or surgical drainage was used. We report our experience during the first 12mo post-transplant of a single transplant surgeon who used each of these modifications among 707 consecutive recipients of kidney-alone transplants at our center since 2014. RESULTS: During the first 12mo post-transplant, 2.3%(16/707) of patients developed a urologic complication; only 1.0%(7/707) required surgical repair of their original ureteroneocystostomy. Additionally, 2.7%(19/707) developed a vascular complication; 8.8%(62/707) developed some other type of surgical complication(wound complication, lymphocele development, or development of a peri-renal hematoma or peri-renal collection). These overall results were clearly advantageous when compared with other studies. CONCLUSION: We believe that this modified kidney transplant technique clearly helped in reducing post-transplant risks of developing urologic/vascular/other surgical complications. Importantly, these results were achieved without initial ureteral stent placement or surgical drainage.

Renal cell carcinoma with an "uncoiling" tumor thrombus: intraoperative shift from level III to level IV.

BACKGROUND: The gold standard treatment for renal cell carcinoma (RCC) with tumor thrombus (TT) is complete surgical excision. The surgery is complex and challenging to the surgeon, especially with large tumor thrombus extending into the inferior vena cava (IVC) and right atrium. Traditionally, these difficult cases required the use of cardiopulmonary bypass (CPB) with or without deep hypothermic cardiac arrest, but in recent years, different surgical techniques derived from the field of liver transplantation have been used in efforts to avoid CPB. CASE PRESENTATION: We present a case of RCC with TT level IIIc (extending above major hepatic veins) that "uncoiled" intraoperatively into the right atrium after division of the IVC ligament, transforming into a level IV TT. Despite the new TT extension, the surgery was successfully completed exclusively through an abdominal approach without CPB and while using intraoperative transesophageal echocardiography (TEE) monitoring and a cardiothoracic team standby. CONCLUSIONS: This case highlights the need for a multidisciplinary approach and the utility of intraoperative continous TEE monitoring which helped to visualize the change of the TT venous extension, allowing the surgical teamto modify their surgical approach as needed avoiding a catastrophic event.

Determinants of hyperparathyroidism in children after kidney transplantation.

INTRODUCTION: Hyperparathyroidism (HPT) can contribute to metabolic bone disease following kidney transplantation. We evaluated post-transplant trends in intact parathyroid hormone (iPTH) and determined predictors of HPT in pediatric kidney transplant (KTx) recipients. METHODS: In this single-center study, retrospective data were collected on 88 children from 2013 to 2019. Data collected included dialysis vintage, biochemical parameters, post-transplant trends in iPTH, 25(OH)Vitamin D levels and estimated glomerular filtration rate (eGFR ml/min/1.73 m2 ). Pre-transplant treatment for HPT was quantified with a Treatment Burden score (TB, score range: 0-100). After log-transforming skewed variables (iPTH and eGFR), multivariable linear regression was performed to determine predictors of log {iPTH} at 6 and 36 months (mo) post-transplant. RESULTS: Median age was 12.8 (range: 1.9-20.5) years, and dialysis vintage was 11.2 (range: 0.0-112.9) months. The majority were of Hispanic and African Ancestry (77.3%). Median post-transplant iPTH was 69.5 (range: 1.8-306.8) pg/ml at 6 mo with a gradual downward trend to 59.0 (range: 28.0-445.0) pg/ml at 36 mo. Significant multivariable predictors of higher log {iPTH} post-transplant included longer dialysis vintage, higher TB, and lower log{eGFR} at 6 mo, and higher TB, lower log{eGFR}, and deceased donor transplant at 36 mo. CONCLUSIONS: Recognition of risk factors for HPT and monitoring iPTH post-transplant may facilitate timely interventions to mitigate cardiovascular and bone disease in pediatric KTx recipients. KEY MESSAGE: Describe serial trends in intact PTH after kidney transplantation. Pre- and post-transplant factors that contribute to persistence or re-occurrence of hyperparathyroidism after kidney transplantation in children include longer dialysis vintage, high pre-transplant treatment burden and decreased post-transplant GFR. Recognition of these factors, and monitoring intact PTH after kidney transplantation, could facilitate timely interventions to mitigate cardiovascular and bone disease in children.

Transplantation: platform to study recurrence of disease.

Beyond the direct benefit that a transplanted organ provides to an individual recipient, the study of the transplant process has the potential to create a better understanding of the pathogenesis, etiology, progression and possible therapy for recurrence of disease after transplantation while at the same time providing insight into the original disease. Specific examples of this include: 1) recurrence of focal segmental glomerulosclerosis (FSGS) after kidney transplantation, 2) recurrent autoimmunity after pancreas transplantation, and 3) recurrence of disease after orthotopic liver transplantation (OLT) for cirrhosis related to progressive steatosis secondary to jejuno-ileal bypass (JIB) surgery. Our team has been studying these phenomena and their immunologic underpinnings, and we suggest that expanding the concept to other pathologic processes and/or transplanted organs that harbor the risk for recurrent disease may provide novel insight into the pathogenesis of a host of other disease processes that lead to organ failure.

Venous vascular reconstruction of a robotically procured right kidney with two renal veins transplanted into a pediatric recipient.

BACKGROUND: Right versus left kidney donor nephrectomy remains a controversial topic in renal transplantation given the increased incidence of right kidney vascular anomalies and associated venous thrombosis. We present the case of a 3-year-old pediatric recipient with urethral atresia and end-stage kidney disease who received a robotically procured living donor right pelvic kidney with two short same-size renal veins and a short ureter. METHODS: We utilized a completely deceased iliac vein system (common iliac vein with both external and internal veins) to extend the two renal veins. Due to the distance between both renal veins, the external iliac vein was anastomosed to the upper hilum renal vein, and the internal iliac vein was anastomosed to the lower hilum renal vein. The donor's short ureter was anastomosed to the recipient's ureter end-to-side. RESULTS: The patient had immediate graft function and there were no post-operative complications. Renal ultrasound was unremarkable at 48 hours post-transplant. Serum creatinine was 0.5 mg/dL at 3 months post-transplant. CONCLUSION: We demonstrate the successful transplantation of a robotically procured right pelvic donor kidney with two short renal veins using a deceased donor iliac vein system for venous reconstruction without increasing technical complications. This technique of venous reconstruction can be used in right kidneys with similar anatomical variations without affecting graft function.

Liver Inclusion Appears to Be Protective Against Graft Loss-Due-to Chronic But Not Acute Rejection Following Intestinal Transplantation.

In intestinal transplantation, while other centers have shown that liver-including allografts have significantly more favorable graft survival and graft loss-due-to chronic rejection (CHR) rates, our center has consistently shown that modified multivisceral (MMV) and full multivisceral (MV) allografts have significantly more favorable acute cellular rejection (ACR) and severe ACR rates compared with isolated intestine (I) and liver-intestine (LI) allografts. In the attempt to resolve this apparent discrepancy, we performed stepwise Cox multivariable analyses of the hazard rates of developing graft loss-due-to acute rejection (AR) vs. CHR among 350 consecutive intestinal transplants at our center with long-term follow-up (median: 13.5 years post-transplant). Observed percentages developing graft loss-due-to AR and CHR were 14.3% (50/350) and 6.6% (23/350), respectively. Only one baseline variable was selected into the Cox model indicating a significantly lower hazard rate of developing graft loss-due-to AR: Transplant Type MMV or MV (p < 0.000001). Conversely, two baseline variables were selected into the Cox model indicating a significantly lower hazard rate of developing graft loss-due-to CHR: Received Donor Liver (LI or MV) (p = 0.002) and Received Induction (p = 0.007). In summary, while MMV/MV transplants (who receive extensive native lymphoid tissue removal) offered protection against graft loss-due-to AR, liver-containing grafts appeared to offer protection against graft loss-due-to CHR, supporting the results of other studies.

Long-term effects of average calcineurin inhibitor trough levels (over time) on renal function in a prospectively followed cohort of 150 kidney transplant recipients.

More favorable clinical outcomes with medium-term follow-up have been reported among kidney transplant recipients receiving maintenance therapy consisting of "reduced-tacrolimus (TAC) dosing," mycophenolate mofetil (MMF), and low-dose corticosteroids. However, it is not clear whether long-term maintenance therapy with reduced-calcineurin inhibitor (CNI) dosing still leads to reduced renal function. A prospectively followed cohort of 150 kidney transplant recipients randomized to receive TAC/sirolimus (SRL) versus TAC/MMF versus cyclosporine microemulsion (CSA)/SRL, plus low-dose maintenance corticosteroids, now has 20 years of post-transplant follow-up. Average CNI trough levels over time among patients who were still alive with functioning grafts at 60, 120, and 180 months post-transplant were determined and ranked from smallest-to-largest for both TAC and CSA. Stepwise linear regression was used to determine whether these ranked average trough levels were associated with the patient's estimated glomerular filtration rate (eGFR) at those times, particularly after controlling for other significant multivariable predictors. Experiencing biopsy-proven acute rejection (BPAR) and older donor age were the two most significant multivariable predictors of poorer eGFR at 60, 120, and 180 months post-transplant (p < 000001 and 0.000003 for older donor age at 60 and 120 months; p = 0.00008 and <0.000001 for previous BPAR at 60 and 120 months). Assignment to CSA also implied a significantly poorer eGFR (but with less magnitudes of effect) in multivariable analysis at 60 and 120 months (p = 0.01 and 0.002). Higher ranked average CNI trough levels had no association with eGFR at any timepoint in either univariable or multivariable analysis (p > 0.70). Long-term maintenance therapy with reduced-CNI dosing does not appear to cause reduced renal function.

The podocyte: glomerular sentinel at the crossroads of innate and adaptive immunity.

Focal segmental glomerulosclerosis (FSGS) is a common glomerular disorder that manifests clinically with the nephrotic syndrome and has a propensity to recur following kidney transplantation. The pathophysiology and therapies available to treat FSGS currently remain elusive. Since the podocyte appears to be the target of apparent circulating factor(s) that lead to recurrence of proteinuria following kidney transplantation, this article is focused on the podocyte. In the context of kidney transplantation, the performance of pre- and post-reperfusion biopsies, and the establishment of in vitro podocyte liquid biopsies/assays allow for the development of clinically relevant studies of podocyte biology. This has given insight into new pathways, involving novel targets in innate and adaptive immunity, such as SMPDL3b, cGAS-STING, and B7-1. Elegant experimental studies suggest that the successful clinical use of rituximab and abatacept, two immunomodulating agents, in our case series, may be due to direct effects on the podocyte, in addition to, or perhaps distinct from their immunosuppressive functions. Thus, tissue biomarker-directed therapy may provide a rational approach to validate the mechanism of disease and allow for the development of new therapeutics for FSGS. This report highlights recent progress in the field and emphasizes the importance of kidney transplantation and recurrent FSGS (rFSGS) as a platform for the study of primary FSGS.

Effects of recipient education disparity on living donor kidney transplant outcomes across different ethnic groups: a retrospective study in the United States.

Background: Previous studies have shown that education level is associated with the prognosis of cadaveric kidney transplant recipients. However, it is unclear whether education affects the prognosis of living kidney transplant (LDKT) recipients. In addition, it remains to be determined whether the uneven distribution of educational levels consistently affects the prognosis of LDKT recipients across ethnic groups (White, Black, Hispanic and Asian). Methods: After establishing inclusion and exclusion criteria, we conducted a retrospective study of LDKT recipients who received their first single LDKT between 2005 and 2020. The LDKT recipients were divided into lower- and higher-education groups according to categorize the educational level of recipients, and transplant outcomes, including graft survival, patient survival, and death-censored graft survival (DCGS), were analyzed and compared. Results: Graft survival, DCGS and patient mortality were significantly better in the higher-education group compared with those in the lower-education group (P<0.001), with the risk of graft failure, death censored graft failure (DCGF) and patient mortality increasing by 11%, 15% and 7% in the lower-education group, respectively. Furthermore, compared with the higher-education group, the risk of graft failure in Black recipients increased by 18% [adjusted hazard ratio (aHR), 1.18; 95% confidence interval (CI): 1.07 to 1.30], and the risk of patient mortality among White recipients decreased by 7% (aHR, 0.93; 95% CI: 0.87 to 0.99). However, there were no significant differences in graft failure and patient mortality among Hispanic and Asian recipients, respectively. Conclusions: This study revealed that LDKT recipients with a higher education level had better transplant outcomes. However, these transplant outcome differences were mainly found in White and Black recipients. These data confirm the significant effect of different levels of education on the prognosis of LDKT recipients.

A Pilot Single-Blinded, Randomized, Controlled Trial Comparing BNT162b2 vs. JNJ-78436735 Vaccine as the Third Dose After Two Doses of BNT162b2 Vaccine in Solid Organ Transplant Recipients.

Solid Organ Transplant (SOT) recipients are at significant higher risk for COVID-19 and due to immunosuppressive medication, the immunogenicity after vaccination is suboptimal. In the previous studies, booster method showed significant benefit in this population. In the current study, we compared using a mix-and-match method vs. same vaccine as a third dose in SOT recipients. This was a patient-blinded, single center, randomized controlled trial comparing BNT162b2 vs. JNJ-78436735 vaccine as the third dose after two doses of BNT162b2 vaccine. We included adult SOT recipients with functional graft who had received two doses of BNT162b2 vaccine. Participants were randomly assigned to receive either BNT162b2 or JNJ-78436735 in one-to-one ratio. Primary outcome was SARS-CoV-2 IgG positivity at 1 month after the third dose. Sixty SOT recipients, including 36 kidney, 12 liver, 2 lung, 3 heart, and 5 combined transplants, were enrolled, and 57 recipients were analyzed per protocol. There were no statistically significant differences between the two vaccine protocols for IgG positivity (83.3% vs. 85.2% for BNT162b2 and JNJ-78436735, respectively, p = 0.85, Odds Ratio 0.95, 95% Confidence Interval 0.23-4.00). Comparison of the geometric mean titer demonstrated a higher trend with BNT162b2 (p = 0.09). In this pilot randomized controlled trial comparing mix and match method vs. uniform vaccination in SOT recipients, both vaccines were safely used. Since this was a small sample sized study, there was no statistically significant difference in immunogenicity; though, the mix and match method showed relatively lower geometric mean titer, as compared to uniform vaccine. Further studies need to be conducted to determine duration of this immunogenicity. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT05047640?term=20210641&draw=2&rank=1, identifier 20210641.

The surgical evolution of radical nephrectomy and tumor thrombectomy: a narrative review.

Background and Objective: Renal cell carcinoma (RCC) accounts for 2-3% of all malignant disease in adults. RCC propagates into the renal vein and inferior vena cava (IVC) in up to 25% of patients with RCC. Despite advances in medical management such as immunotherapy, surgical resection remains the gold standard treatment of RCC with venous tumor thrombus (TT) extension. Surgical innovation has revolutionized the management of RCC with TT, reducing morbidity and mortality through advanced surgical techniques and minimally invasive approaches. The aim of this review is to summarize the evolving developments in the surgical treatment of RCC with venous TT. Methods: We performed an advanced search on PubMed between the inception of the database and April 2022 to summarize the evolution of the surgical management of RCC with venous TT, focusing on the reports of key historical, current, and recent studies. Key Content and Findings: Implementation of entirely intraabdominal liver transplant-based approaches have allowed for successful surgical excision of higher-level tumor thrombi, obviating the need for sternotomy or cardiopulmonary bypass (CPB). Recent advances in robotic surgery provide a promising approach for minimally invasive management of RCC with venous TT extension. Conclusions: Surgical innovation has revolutionized the management of RCC with TT, reducing morbidity and mortality through minimally invasive techniques with preserved oncologic effectiveness.

The importance of avoiding time-dependent bias when testing the prognostic value of an intervening event - Two acute cellular rejection examples in intestinal transplantation.

In testing the prognostic value of the occurrence of an intervening event (clinical event that occurs posttransplant), 3 proper statistical methodologies for testing its prognostic value exist (time-dependent covariate, landmark, and semi-Markov modeling methods). However, time-dependent bias has appeared in many clinical reports, whereby the intervening event is statistically treated as a baseline variable (as if it occurred at transplant). Using a single-center cohort of 445 intestinal transplant cases to test the prognostic value of first acute cellular rejection (ACR) and severe (grade of) ACR on the hazard rate of developing graft loss, we demonstrate how the inclusion of such time-dependent bias can lead to severe underestimation of the true hazard ratio (HR). The (statistically more powerful) time-dependent covariate method in Cox's multivariable model yielded significantly unfavorable effects of first ACR (P < .0001; HR = 2.492) and severe ACR (P < .0001; HR = 4.531). In contrast, when using the time-dependent biased approach, multivariable analysis yielded an incorrect conclusion for the prognostic value of first ACR (P = .31, HR = 0.877, 35.2% of 2.492) and a much smaller estimated effect of severe ACR (P = .0008; HR = 1.589; 35.1% of 4.531). In conclusion, this study demonstrates the importance of avoiding time-dependent bias when testing the prognostic value of an intervening event.