Kidney Transplant Outcomes Associated With the Use of Increased Risk Donors in Children

Sarah J. Kizilbash; Michelle N. Rheault; Qi Wang; David M. Vock; Srinath Chinnakotla; Tim Pruett; Blanche M. Chavers

Disclosures

American Journal of Transplantation. 2019;19(6):1684-1692. 

In This Article

Abstract and Introduction

Abstract

Increased risk donors (IRDs) may inadvertently transmit blood-borne viruses to organ recipients through transplant. Rates of IRD kidney transplants in children and the associated outcomes are unknown. We used the Scientific Registry of Transplant Recipients to identify pediatric deceased donor kidney transplants that were performed in the United States between January 1, 2005 and December 31, 2015. We used the Cox regression analysis to compare patient and graft survival between IRD and non-IRD recipients, and a sequential Cox approach to evaluate survival benefit after IRD transplants compared with remaining on the waitlist and never accepting an IRD kidney. We studied 328 recipients with and 4850 without IRD transplants. The annual IRD transplant rates ranged from 3.4% to 13.2%. IRDs were more likely to be male (P = .04), black (P < .001), and die from head trauma (P = .006). IRD recipients had higher mean cPRA (0.085 vs 0.065, P = .02). After multivariate adjustment, patient survival after IRD transplants was significantly higher compared with remaining on the waitlist (adjusted hazard ratio [aHR]: 0.48, 95% CI: 0.26-0.88, P = .018); however, patient (aHR: 0.93, 95% CI: 0.54-1.59, P = .79) and graft survival (aHR: 0.89, 95% CI: 0.70-1.13, P = .32) were similar between IRD and non-IRD recipients. We recommend that IRDs be considered for transplant in children.

Introduction

Kidney transplant is the treatment of choice for end-stage renal disease (ESRD); however, access to transplant is limited by a severe organ shortage. In 2016, 95 000 patients were active on the waitlist for a kidney transplant; however, only 13 501 patients received a deceased donor kidney.[1] In the same year, 917 new pediatric candidates were added to the waitlist but only 583 received a deceased donor transplant.[1] Children on dialysis have six times higher mortality rates compared with children with a functioning graft, highlighting the importance of kidney transplant in this population.[2] The gap between the organ supply and demand is enormous and underscores the necessity to expand the existing deceased donor pool. A recent decline in living donation for pediatric recipients further emphasizes the urgency to increase the deceased donor availability.[1]

In 1994, the Centers for Disease Control and Prevention (CDC) defined increased-risk donors (IRDs) in an effort to minimize transplant associated viral infection transmission. The definition of CDC IRDs was updated in 2013.[3] Under the new definition, 20% of all deceased donors fall under the category of IRDs.[4] These donors are at risk of transmitting newly acquired HIV, hepatitis B, and/or hepatitis C infection(s) to recipients through transplant because of the inability of enzyme-linked-immunosorbent assay (ELISA) and viral nucleic acid (NAT) test to detect window period (interval between infection and detection) infections.[3] IRDs carry a low (<1%) but non-zero risk of infection transmission.[5,6]

Despite the severe organ shortage, 20% of kidneys are discarded annually.[7] Discarded kidneys frequently come from expanded criteria donors or donation after cardiac death. However, IRD kidneys are also discarded at 1.5 times the rate of standard criteria donors.[8] Barring the infection risk, IRD kidneys are high-quality kidneys.[9] Adult studies comparing IRDs with standard criteria donors have demonstrated comparable short-term patient and graft survival without a significant increase in infection transmission.[10,11] There are no studies investigating the outcomes of CDC IRD kidney transplant in children.

In order to ameliorate the organ shortage, it is important that we characterize the utilization of suboptimal donors such as IRDs. This is particularly relevant to pediatric patients because IRDs are more likely to be allocated to younger recipients, under the new kidney allocation system.[12] Furthermore, the IRD number is expected to increase due to the growing epidemic of intravenous drug abuse.[13] Hence, discarding IRD organs indiscriminately or avoiding their use in children would adversely affect the already limited organ supply.

The primary objective of this study was to investigate the outcomes of IRD kidney transplant in children. We compared overall patient and graft survival between IRD and non-IRD recipients. We also evaluated patient survival after IRD transplants compared with remaining on the waitlist and never accepting an IRD kidney (but possibly accepting a non-IRD kidney). We hypothesized that IRD transplant recipients would have superior patient and graft survival due to the higher quality of these organs. To our knowledge, this is the largest and first national study to examine the use of CDC IRDs in pediatric kidney transplant recipients.

Comments

3090D553-9492-4563-8681-AD288FA52ACE

processing....