Current Opinion in Organ Transplantation最新文献

Purpose of review: This review will focus on the epidemiological data, risk factors, and management of stroke before and after kidney transplant. Stroke is highly prevalent in waitlisted patients as well as kidney transplant recipients and is associated with impaired transplant outcomes. Multiple traditional, nontraditional, and transplanted risk factors increase the risk of stroke.

Recent findings: Although the risk of stroke is reduced after kidney transplantation compared with remaining on dialysis, the morbidity and mortality from stroke after transplantation remain significant.

Summary: Early screening for risk factors before and after a kidney transplant and following the Kidney Disease Improving Global Outcomes (KDIGO) management guidelines could minimize the incidence of stroke and transplant outcomes.

Purpose of the review: This review describes the sex disparity in liver transplantation (LT) and explains its underlying causes.

Recent findings: There is a small but persistent sex disparity in transplant rate and waitlist mortality that disappears once women are listed as Status 1. Allocation systems that could replace the Model for End Stage Liver Disease (MELD)-Na with scores less reliant on serum creatine and muscle mass have the potential to alleviate part of the sex disparity. Women perform worse on frailty assessments and are more likely to have nonalcoholic steatohepatitis (NASH). A diagnosis of NASH is compounding risk factor for frailty.

Summary: Women remain disadvantaged in their access to LT despite multiple evolutions of the allocation system. An allocation system that relies less heavily on serum creatinine could partially alleviate the sex disparity. As NASH becomes more prevalent and frailty becomes more important in listing decisions, we may also need to carefully consider differences in the manifestations of frailty between the genders.

Purpose of review: Kidney transplantation in low-weight recipients (<15 kg) is a challenging surgery with special characteristics. We proposed to perform a systematic review to determine the postoperative complication rate and the type of complications after kidney transplantation in low-weight recipients (<15 kg). The secondary objectives were to determine graft survival, functional outcomes, and patient survival after kidney transplantation in low-weight recipients.

Methods: A systematic review was performed according to preferred reporting items for systematic reviews and meta-analyses. Medline and Embase databases were searched to identify all studies reporting outcomes on kidney transplantation in low-weight recipients (<15 kg).

Results: A total of 1254 patients in 23 studies were included. The median postoperative complications rate was 20.0%, while 87.5% of those were major complications (Clavien ≥3). Further, urological and vascular complications rates were 6.3% (2.0-11.9) and 5.0% (3.0-10.0), whereas the rate of venous thrombosis ranged from 0 to 5.6%. Median 10-year graft and patient survival were 76 and 91.0%.

Summary: Kidney transplantation in low-weight recipients is a challenging procedure complicated by a high rate of morbidity. Finally, pediatric kidney transplantation should be performed in centers with expertise and multidisciplinary pediatric teams.

Purpose of review: As policies governing liver transplantation (LT) continue to change and influence clinical practice, it is important to monitor trends in equitable access and outcomes amongst patients. The purpose of this review is to closely examine recent advances and findings in health equity research in LT over the last 2 years; specifically evaluating inequities at the different stages of LT (referral, evaluation, listing, waitlist outcomes and post-LT outcomes).

Recent findings: Advancements in geospatial analysis have enabled investigators to identify and begin to study the role of community level factors (such as neighborhood poverty, increased community capital/urbanicity score) in driving LT disparities. There has also been a shift in investigating center specific characteristics that contributes to disparities in waitlist access. Modification to the current model for end stage liver disease (MELD) score policy accounting for height differences is also crucial to eradicating the disparity in LT amongst sexes. Lastly, Black pediatric patients have been shown to have higher rates of death and worse posttransplant outcome after transitioning to adult healthcare.

Summary: Although, there have been some advances in methodology and policies, inequities in waitlist access, waitlist outcomes and posttransplant outcomes continue to be pervasive in the field of LT. Future directions include expansion of social determinants of health measures, inclusion of multicenter designs, MELD score modification and investigation into drivers of worse posttransplant outcomes in Black patients.

Purpose of review: To summarize the current state of liver transplantation (LT) for unresectable colorectal liver metastases (uCRLM), and to address future directions.

Recent findings: The Norwegian secondary cancer (SECA) I and SECA II studies demonstrated that after LT the 5-year survival of a highly selected group of patients with uCRLM could be as high as 60% and 83%, respectively. After long-term follow-up, the 5- and 10-year survival was shown to be 43% and 26%, respectively. Furthermore, data has accumulated in other countries and a North American study reported a 1.5-year survival of 100%. In addition, steady growth has been demonstrated in the US, with 46 patients transplanted to date and 19 centers enrolling patients for this indication. Lastly, although recurrence is almost universal in patients with a high tumor burden, it has not been an accurate surrogate for survival, reflecting the relatively indolent nature of recurrence after LT.

Summary: Growing evidence has shown that excellent survival and even cure can be achieved in highly selected patients with uCRLM, with survival rates far superior than in patients treated with chemotherapy. The next step is to create national registries to standardize selection criteria and establish the optimal approach and best practices for incorporating LT for uCRLM into the treatment armamentarium.

Purpose of review: Pregnancy in solid organ transplantation (SOT) is a very complex part of transplant medicine wherein there is scarce information available in the literature. Solid organ transplant recipients often have comorbidities, such as hypertension and diabetes, which add additional risk to a pregnancy.

Recent findings: We present this review article on the various aspects of different types of immunosuppressant medications used in pregnancy with added inputs on contraception and fertility after transplant. We described the antepartum and postpartum considerations and discussed the adverse effects of the immunosuppressive medications. Maternal and fetal complications of each SOT have been also discussed in this article.

Summary: This article will serve as the primary review articles for the use of immunosuppressive medications during pregnancy with consideration during pregnancy after SOT.

Purpose of review: With the inherent therapeutic limitations of gut transplantation, the concept of surgical gut rehabilitation was introduced to restore nutritional autonomy in pediatric patients. With favorable outcomes in these young patients, there has been increasing interest in the applicability of gut rehabilitative surgery to a growing population of adults with gut failure due to various etiologies. We aim to review the current status of surgical gut rehabilitation for adult gut failure patients in the era of multidisciplinary gut rehabilitation and transplantation.

Recent findings: Indications for surgical gut rehabilitation have been gradually expanding, with gut failure after bariatric surgery recently added. Serial transverse enteroplasty (STEP) has been used with favorable outcomes in adult patients, including those with intrinsic intestinal disease. Autologous gut reconstruction (AGR) is the most frequently used surgical rehabilitative method; its outcome is further improved with conjunctive use of bowel lengthening and enterocyte growth factor as a part of comprehensive gut rehabilitation.

Summary: Accumulated experiences have validated the efficacy of gut rehabilitation for survival, nutritional autonomy, and quality of life in adults with gut failure of various etiology. Further progress is expected with growing experience around the world.

Purpose of review: The COVID-19 pandemic revolutionized the field of lung transplantation, as lung transplant is now an acceptable life-saving therapy for select patients with COVID-19-associated acute respiratory distress syndrome (ARDS), while prior to the pandemic, few transplants were performed for ARDS. This review article details the establishment of lung transplantation as a viable therapy for COVID-19-related respiratory failure, how to evaluate COVID-19 patients for lung transplant, and specific technical considerations for the operation.

Recent findings: Lung transplantation is a life-altering treatment for two distinct cohorts of COVID-19 patients: those with irrecoverable COVID-19-associated ARDS and those who recover from the initial COVID-19 insult but are left with chronic, debilitating post-COVID fibrosis. Both cohorts require stringent selection criteria and extensive evaluation to be listed for lung transplantation. As the first COVID-19 lung transplantation was recently performed, long-term outcomes are lacking; however, short-term outcome data of COVID-19-related lung transplants are promising.

Summary: Given the challenges and complexities associated with COVID-19-related lung transplantation, strict patient selection and evaluation are required with an experienced multidisciplinary team at a high-volume/resource center. With promising short-term outcome data, ongoing studies are needed to assess long-term outcomes of COVID-19-related lung transplants.

Purpose of review: Optimizing deceased donor organ utilization is gaining recognition as a topical and important issue, both in the United Kingdom (UK) and globally. This review discusses pertinent issues in the field of organ utilization, with specific reference to UK data and recent developments within the UK.

Recent findings: A multifaceted approach is likely required in order to improve organ utilization. Having a solid evidence-base upon which transplant clinicians and patients on national waiting lists can base decisions regarding organ utilization is imperative in order to bridge gaps in knowledge regarding the optimal use of each donated organ. A better understanding of the risks and benefits of the uses of higher risk organs, along with innovations such as novel machine perfusion technologies, can help clinician decision-making and may ultimately reduce the unnecessary discard of precious deceased donor organs.

Summary: The issues facing the UK with regards to organ utilization are likely to be similar to those in many other developed countries. Discussions around these issues within organ donation and transplantation communities may help facilitate shared learning, lead to improvements in the usage of scarce deceased donor organs, and enable better outcomes for patients waiting for transplants.

Purpose of review: Lung transplant is a life-saving intervention for many with end-stage lung disease. As usable donor lungs are a limited resource and the risk of death on the waitlist is not uniform among candidates, organ allocation must consider many variables in order to be equitable.

Recent findings: The lung allocation score (LAS) system, implemented in 2005, accounted for disease severity, risk of death without transplant, and 1-year survival estimates; however, recipient size, allosensitization, and blood type, biologic features that influence donor pool for a given recipient, do not impact allocation priority. Additionally, social determinants such as geography, socioeconomic status, race, and ethnicity can impact the likelihood of receiving a transplant. This has resulted in certain groups being transplanted at lower rates and at higher risk of dying on the waitlist. In order to address these disparities, lung organ allocation in the United States transitioned to a continuous distribution system using the composite allocation score (CAS) on 9 March 2023.

Summary: In this article, we will review some of the data demonstrating the impact that biologic and social determinants have had on lung allocation in order to provide background as to why these have been incorporated into the CAS.