Non-immunologic allograft loss in pediatric kidney transplant recipients

Approach to acute kidney injury following paediatric kidney transplant

PURPOSE OF REVIEW

In a child with evidence of acute kidney injury (AKI) following renal transplantation, it is important to quickly and accurately diagnose the cause to enable timely initiation of therapeutic interventions. The following article will discuss the differential diagnosis of acute graft dysfunction in paediatric kidney transplant recipients. This review will systematically guide the clinician through the common and less common causes and provide updates on current treatments.

RECENT FINDINGS

In patients with signs of graft dysfunction, rejection is an important cause to consider. Diagnosis of rejection relies on biopsy findings, an invasive and costly technique. Over the past 5 years, there has been a focus on noninvasive methods of diagnosing rejection, including serum and urinary biomarkers.

SUMMARY

This review discusses the differential diagnosis of acute graft dysfunction following transplant, with a focus on acute rejection, urinary tract infections and common viral causes, prerenal and postrenal causes, nephrotoxic medications, specifically calcineurin inhibitor toxicity, thrombotic microangiopathy and recurrence of the underlying disease. Each condition is discussed in detail, with a focus on clinical clues to the cause, incidence in the paediatric population, workup and treatment.

Language barriers and kidney transplantation in children

BACKGROUND

Understanding disparities in pediatric kidney transplants is important to provide equitable care. We compared transplant outcomes between English-speaking (ES) and interpreter-needing (IN) pediatric kidney transplant recipients.

METHODS

Through retrospective review, primary kidney transplant recipients, 0-21 years transplanted between 2005 and 2019, were divided into ES and IN cohorts. Continuous and categorical variables were compared using Wilcoxon rank-sum, Welch two-sample t-test, and chi-squared analyses. Patient survival, graft survival, and rejection-free survival were evaluated using Kaplan-Meier methods and Cox regression. Days hospitalized were evaluated using negative binomial regression.

RESULTS

Our sample included 211 ES and 37 IN transplant recipients. Compared with the ES, the IN cohort was older at transplant (14.56 vs. 11.03 years; p < 0.01), had more time between kidney failure and transplant (0.9 vs. 0.3 years; p < 0.01), and more often received deceased over living donor transplants (78.4% vs. 30.4%; p < 0.01). Multivariate Cox proportional-hazard models evaluating adjusted 5-year patient survival demonstrated decreased 5-year post-transplant survival in the IN cohort (aHR = 10.10, 95% CI: 1.5, 66.8; p = 0.02). We did not identify differences in 5-year death-censored graft survival (aHR = 0.57; 95% CI: 0.14, 2.4; p = 0.4) nor rejection-free survival (aHR = 0.8; 95% CI: 0.4, 1.5; p = 0.5). We found significantly fewer hospitalization events in the IN cohort during the first year post-transplant (aRR: 0.62; 95% CI: 0.4, 0.9; p = 0.01) but no difference 5-year post-transplant. The IN cohort had more missed outpatient appointments (10.4% vs. 2.8%; p = 0.03) and undetectable serum immunosuppressant levels (mean: 3.8% vs. 1.3%; p = 0.02) 5 years post-transplant.

CONCLUSIONS

Pediatric kidney transplant recipients requiring interpreter services for healthcare delivery demonstrate fewer post-transplant interactions with their healthcare team (fewer hospitalizations and more no-show visits) and lower 5-year patient survival compared with recipients not requiring interpreters. A higher resolution version of the Graphical abstract is available as Supplementary information.

How to Deal With Kidney Retransplantation-Second, Third, Fourth, and Beyond

Kidney transplantation is the best health option for patients with end-stage kidney disease. Ideally, a kidney transplant would last for the lifetime of each recipient. However, depending on the age of the recipient and details of the kidney transplant, there may be a need for a second, third, fourth, or even more kidney transplants. In this overview, the outcome of multiple kidney transplants for an individual is presented. Key issues include surgical approach and immunologic concerns. Included in the surgical approach is an analysis of transplant nephrectomy, with indications, timing, and immunologic impact. Allograft thrombosis, whether related to donor or recipient factors merits investigation to prevent it from happening again. Other posttransplant events such as rejection, viral illness (polyomavirus hominis type I), recurrent disease (focal segmental glomerulosclerosis), and posttransplant lymphoproliferative disease may lead to the need for retransplantation. The pediatric recipient is especially likely to need a subsequent kidney transplant. Finally, noncompliance/nonadherence can affect both adults and children. Innovative approaches may reduce the need for retransplantation in the future.

Changes in blood glucose level after renal transplantation in pediatrics: A study of risk factors of new-onset diabetes after transplantation

BACKGROUND

New-onset diabetes after transplantation refers to the development of diabetes after solid organ transplantation without a history of diabetes and is related to poor graft function and lower survival rate. In the kidney transplant population, NODAT occurs in 24% of adults and 9% of children. The real incidence and risk factors in the pediatric population is unknown, which we aimed to determine in this study.

METHODS

A retrospective study was conducted in patients who underwent kidney transplantation in the Pediatric Nephrology Service of the "Federico Gómez" Children's Hospital of Mexico.

RESULTS

The study included 127 children divided into groups 1 and 2 (without [n = 110 patients, 86.5%] and with NODAT [n = 17 patients, 13.4%], respectively), with median ages of 14 years (interquartile range [IQR], 9-16 years) and 15 years (IQR, 13-16 years; p = .3), respectively. Cox proportional hazards analysis revealed an association between changes from baseline to 24-h postoperative blood glucose level as a risk factor of the development of NODAT. This implies that each unit increase in blood glucose level in the first hours after transplantation also increases the risk of developing diabetes (95% confidence interval, 1.011-1.021; p = <.001).

CONCLUSIONS

Post-kidney transplant patients require immediate follow-up, and attention should be paid to changes in blood glucose level in the first 24 h after transplantation, as any alteration may be an early sign of development of NODAT, especially in patients with a family history of diabetes mellitus.

Emerging monitoring technologies in kidney transplantation

Non-invasive technologies to monitor kidney allograft health utilizing high-throughput assays of blood and urine specimens are emerging out of the research realm and slowly becoming part of everyday clinical practice. HLA epitope analysis and eplet mismatch score determination promise a more refined approach to the pre-transplant recipient-donor HLA matching that may lead to reduced rejection risk. High-resolution HLA typing and multiplex single antigen bead assays are identifying potential new offending HLA antibody subtypes. There is increasing recognition of the deleterious role non-HLA antibodies play in post-transplant outcomes. Donor-derived cell-free DNA detected by next-generation sequencing is a promising biomarker for kidney transplant rejection. Multi-omics techniques are shedding light on discrete genomic, transcriptomic, proteomic, and metabolomic signatures that correlate with and predict allograft outcomes. Over the next decade, a comprehensive approach to optimize kidney matching and monitor transplant recipients for acute and chronic graft dysfunction will likely involve a combination of those emerging technologies summarized in this review.