OPTN/SRTR 2016 Annual Data Report: Introduction

Varicella-zoster virus post-exposure management and prophylaxis: A review

Varicella-zoster virus causes both varicella (chickenpox) and herpes zoster (shingles). Although varicella incidence has dramatically declined since introduction of the live-attenuated varicella vaccine, vaccination rates are suboptimal, and outbreaks still occur. Additionally, herpes zoster incidence continues to rise. Severe or fatal complications may result from varicella transmission to at-risk individuals who are exposed to either varicella or herpes zoster. An increasing number of children and adults are receiving immunosuppressive therapies and are at high risk for severe varicella and other complications if exposed to the virus. Clinical management of individuals exposed to varicella-zoster virus should take into consideration the type of exposure, evidence of immunity, and host-immune status with regard to ability to receive varicella vaccination safely. Post-exposure varicella vaccination may prevent infection or mitigate disease severity in persons eligible for vaccination. Post-exposure prophylaxis with varicella zoster immune globulin is indicated for populations ineligible for vaccination, including immunocompromised children and adults, pregnant women, newborns of mothers with varicella shortly before or after delivery, and premature infants. Appropriate post-exposure management of individuals exposed to either varicella or herpes zoster-including assessment of immune status and rapid provision of optimal prophylaxis-can help avoid potentially devastating complications of varicella-zoster virus infection.

Expanding deceased donor kidney transplantation: medical risk, infectious risk, hepatitis C virus, and HIV

PURPOSE OF REVIEW

Due to the organ shortage, which prevents over 90 000 individuals in the United States from receiving life-saving transplants, the transplant community has begun to critically reevaluate whether organ sources that were previously considered too risky provide a survival benefit to waitlist candidates.

RECENT FINDINGS

Organs that many providers were previously unwilling to use for transplantation, including kidneys with a high Kidney Donor Profile Index or from increased risk donors who have risk factors for window period hepatitis C virus (HCV) and HIV infection, have been shown to provide a survival benefit to transplant waitlist candidates compared with remaining on dialysis. The development of direct-acting antivirals to cure HCV infection has enabled prospective trials on the transplantation of organs from HCV-infected donors into HCV-negative recipients, with promising preliminary results. Changes in legislation through the HIV Organ Policy Equity Act have legalized transplantations from HIV-positive deceased donors to HIV-positive recipients for the first time in the United States.

SUMMARY

Critical reexamination of deceased donor organs that were previously discarded has resulted in greater utilization of these organs, an increased number of deceased donor transplants, and the provision of life-saving treatment to more transplant waitlist candidates.

Prospective Validation of Prediction Model for Kidney Discard

BACKGROUND

Many kidneys are discarded every year, with 3631 kidneys discarded in 2016 alone. Identifying kidneys at high risk of discard could facilitate "rescue" allocation to centers more likely to transplant them. The Probability of Delay or Discard (PODD) model was developed to identify marginal kidneys at risk of discard or delayed allocation beyond 36 hours of cold ischemia time. However, PODD has not been prospectively validated, and patterns of discard may have changed after policy changes such as the introduction of Kidney Donor Profile Index and implementation of the Kidney Allocation System (KAS).

METHODS

We prospectively validated the PODD model using Scientific Registry of Transplant Recipients data in the KAS era (January 1, 2015, to March 1, 2018). C statistic was calculated to assess accuracy in predicting kidney discard. We assessed clustering in centers' utilization of kidneys with PODD >0.6 ("high-PODD") using Gini coefficients. Using match run data from January 1, 2015, to December 31, 2016, we examined distribution of these high-PODD kidneys offered to centers that never accepted a high-PODD kidney.

RESULTS

The PODD model predicted discard accurately under KAS (C-statistic, 0.87). Compared with utilization of low-PODD kidneys (Gini coefficient = 0.41), utilization of high-PODD kidneys was clustered more tightly among a few centers (Gini coefficient, 0.84 with >60% of centers never transplanted a high-PODD kidneys). In total, 11684 offers (35.0% of all high-PODD offers) were made to centers that never accepted a high-PODD kidney.

CONCLUSIONS

Prioritizing allocation of high-PODD kidneys to centers that are more likely to transplant them might help reduce kidney discard.

Seeking new answers to old questions about public reporting of transplant program performance in the United States

The Scientific Registry of Transplant Recipients (SRTR) is mandated by the National Organ Transplant Act, the Final Rule, and the SRTR contract with the Health Resources and Services Administration to report program-specific information on the performance of transplant programs. Following a consensus conference in 2012, SRTR developed a new version of the public website to improve public reporting of often complex metrics, including changing from a 3-tier to a 5-tier summary metric for first-year posttransplant survival. After its release in December 2016, the new presentation was moved to a "beta" website to allow collection of additional feedback. SRTR made further improvements and released a new beta website in May 2018. In response to feedback, SRTR added 5-tier summaries for standardized waitlist mortality and deceased donor transplant rate ratios, along with an indicator of which metric most affects survival after listing. Presentation of results was made more understandable with input from patients and families from surveys and focus groups. Room for improvement remains, including continuing to make the data more useful to patients, deciding what additional data elements should be collected to improve risk adjustment, and developing new metrics that better reflect outcomes most relevant to patients.

Approach to Transplant Infectious Diseases in the Emergency Department

The emergency department (ED) is an increasingly important site of care for patients who have undergone solid organ transplantation or hematopoietic cell transplantation. It is paramount for emergency physicians to recognize infections early on, obtain appropriate diagnostic testing, initiate empirical antimicrobial therapy, and consider specialty consultation and inpatient admission when caring for these patients. This review provides emergency physicians with an approach to the assessment of transplant patients' underlying risk for infection, formulation of a broad differential diagnosis, and initial management of transplant infectious disease emergencies in the ED.