Ethical tensions in solid organ transplantation： The price of success

Solid organ transplantation has rapidly developed into the therapy a choice for end-stage organ failure. The expansion of its use has resulted is a large deficiency in organ supply. To address this, the field of organ transplantation has attempted to develop new strategies that would increase the availability of organs for transplant. Some of these strategies include expansion of the donor pool by increasing the number of living donors or using deceased donor organs that may be marginal or "expanded". The intent is to bring life-saving therapy to individuals in need; however, much of this expansion has been brought forward without clear prospective guidelines. This article focuses on the current disparity between organ supply and demand, and how this has impacted the use of living donors and development of the "expanded donor" concept.     

Acute myeloid leukemia following solid organ transplantation: entity or novelty?

Due to the rarity of the disease, the characteristics of acute myeloid leukemia following solid organ transplantation (post‐transplant AML; PT‐AML) are unclear; furthermore, it is not known for certain whether PT‐AML is a separate entity or not. We provide a systematic review of all previously reported cases of PT‐AML in the English literature (n = 51). 45% of cases occurred after renal transplantation, and 72% were males. The median age at diagnosis of AML was 50 yr, with a median transplant‐to‐AML interval of 3.8 yr and a rapid decline in incidence after 5 yr. 26% of patients were asymptomatic at the time of presentation, and 42% were pancytopenic. M0/M1/M2, M3, M4/M5, and M6/M7 subtypes comprised 17%, 25%, 39%, and 19% of all cases, respectively. 36% of patients had unfavorable cytogenetic risk disease. The median overall survival was only 3 months. We observed several transplant‐specific features: (i) The transplant‐to‐AML interval follows two very different patterns between renal vs. liver transplant patients. (ii) All 4 cases of donor cell leukemia occurred after liver transplant. (iii) Unfavorable risk disease was marginally significantly more common among renal compared with liver transplant patients (P = 0.057). Our results suggest that PT‐AML is a separate entity with distinct characteristics, which need to be investigated further in future research. Heavy post‐transplant immunosuppression likely plays a key role in the pathogenesis of PT‐AML.     

The rectal remnant after total colectomy for colitis – intra-operative,post-operative and longer-term considerations

Objectives: Acute severe colitis requires surgery in around 30% of the cases. Total colectomy with ileostomy is the standard procedure with distinct advantages to a laparoscopic approach. Less agreement exists regarding the formation or configuration of the retained rectal stump and its short-term and long-term management. In this review, aspects of management of the rectal remnant, including perioperative considerations, potential complications, medical treatment, surveillance and implications for proctectomy and reconstructive surgery are explored.

Methods: A thorough literature review exploring the PubMed and EMBASE databases was undertaken to clarify the evidence base surrounding areas of controversy in the surgical approach to acute severe colitis. In particular, focus was given to evidence surrounding management of the rectal remnant.

Results: There is a paucity of high quality evidence for optimal management of the rectal stump following colectomy, and randomised trials are lacking. Establishment of laparoscopic colectomy has been associated with distinct advantages as well as the emergence of unique considerations, including those specific to rectal remnant management.

Conclusions: Early surgical involvement and a multidisciplinary approach to the management of acute severe colitis are advocated. Laparoscopic subtotal colectomy and ileostomy should be the operation of choice, with division of the rectum at the pelvic brim leaving a closed intraperitoneal remnant. If the rectum is severely inflamed, a mucus fistula may be useful, and an indwelling rectal catheter is probably advantageous to reduce the complications associated with stump dehiscence. Patients electing not to proceed to proctectomy should undergo surveillance for dysplasia of the rectum.     

Infections and solid organ transplant rejection: a cause-and-effect relationship?

Although evidence is far from being conclusive, several studies have suggested that infections could trigger rejection in different transplant settings. In this review we examine the evidence linking cytomegalovirus (CMV), adenovirus, enterovirus, parvovirus, and herpes simplex virus infections to the vasculopathy leading to cardiac allograft rejection, the association between CMV and chronic kidney, lung, and liver graft rejection, and the association of human herpesvirus 6 reactivation with CMV-related disease in kidney and liver transplant recipients. We also review the numerous antiviral prophylactic or pre-emptive treatments in use to control CMV infection, and suggest that they do not limit immune reactions leading to graft rejection or lower the risk of developing post-transplantation atherosclerosis in allograft recipients. Finally, we emphasise the need for prospective, international studies to clarify the role of infections in transplant rejection, to look at virus-to-virus interactions, and to establish specific therapeutic strategies. Such strategies must not rely exclusively on expensive antiviral agents but also on vaccination or other, innovative approaches, such as the use of agents able to inhibit the activity of natural killer cells, which might have an important role in acute allograft rejection.     

Epstein–Barr viral load in whole blood of adults with posttransplant lymphoproliferative disorder after solid organ transplantation does not correlate with clinical course

Posttransplant lymphoproliferative disease (PTLD) is closely linked to primary Epstein–Barr virus (EBV) infection. A defect of EBV specific cellular immunity is postulated to play a pivotal role in the etiology of PTLD, but there is some debate as to whether EBV load in the peripheral blood of transplant patients predicts onset of PTLD or relapse after treatment. The current prospective, single-center study was undertaken to investigate the impact of therapy on EBV load in adult patients with PTLD. Fifteen patients with PTLD after solid organ transplantation were included and of these, seven had EBV-associated PTLD. All 15 patients received Rituximab as primary therapy. In cases of treatment failure or relapse after Rituximab treatment, patients received polychemotherapy according to the cyclophosphamide, vincristine, doxorubicin, and prednisone regimen. At onset of PTLD, the median EBV load in the peripheral blood of patients was higher in EBV-associated PTLD than PTLD with no associated EBV infection. After Rituximab therapy, four of seven patients with EBV-associated PTLD achieved long-lasting complete remissions. However, in two of these patients, EBV load increased to reach levels as high as those recorded at onset of PTLD. Another patient showed a dramatic decline of EBV load after the first dose of Rituximab while suffering from progressive disease. The other patient relapsed after Rituximab monotherapy, but his viral load stayed low. In total, discordance in EBV load and clinical course was observed in five of the seven patients with EBV-associated PTLD. We conclude that in adult patients with PTLD, EBV load does not correlate with treatment response and is not suitable as a predictive marker for PTLD relapse.     

Cytomegalovirus infection after liver transplantation： Current concepts and challenges

Cytomegalovirus （CMV） is a common viral pathogen that influences the outcome of liver transplantation. In addition to the direct effects of CMV syndrome and tissue-invasive diseases, CMV is associated with an increased predisposition to acute and chronic allograft rejection, accelerated hepatitis C recurrence, and other opportunistic infections, as well as reduced overall patient and allograft survival. Risk factors for CMV disease are often interrelated, and include CMV D＋/R- serostatus, acute rejection, female gender, age, use of high-dose mycophenolate mofetil and prednisone, and the overall state of immunity. In addition to the role of CMV-specific CD4＋ and CD8＋ T lymphocytes, there are data to suggest that functionality of the innate immune system contributes to CMV disease pathogenesis. In one study, liver transplant recipients with a specific polymorphism in innate immune molecules known as Toll-like receptors were more likely to develop higher levels of CMV replication and clinical disease. Because of the direct and indirect adverse effects of CMV disease, its prevention, whether through antiviral prophylaxis or preemptive therapy, is an essential component in improving the outcome of liver transplantation. In the majority of transplant centers, antiviral prophylaxis is the preferred strategy over preemptive therapy for the prevention of CMV disease in CMV-seronegative recipients of liver allografts from CMV-seropositive donors （D＋/R-）. However, the major drawback of antiviral prophylaxis is the occurrence of delayed-onset primary CMV disease. In several prospective and retrospective studies, the incidence of delayed-onset primary CMV disease ranged from 16% to 47% of CMV D＋/R- liver transplant recipients.Current data suggests that delayed-onset CMV disease is associated with increased mortality after liver transplantation. Therefore, optimized strategies for prevention and novel drugs with unique modes of action are needed. Currently, a randomized controlled clinical trial is being perf     

Foscarnet – an alternative for cytomegalovirus prophylaxis after allogeneic stem cell transplantation?

 Cytomegalovirus (CMV) disease is a serious complication after allogeneic hematopoietic stem cell transplantation (HSCT) and is associated with high morbidity and mortality. Early detection of the disease by antigenemia testing and polymerase chain reaction (PCR) along with pre-emptive antiviral therapy has been shown to be very effective in decreasing the incidence of CMV. We performed an uncontrolled observational study in 21 patients after HSCT (14 related, 7 unrelated donors) to evaluate the efficacy and toxicity of foscarnet administered as prophylaxis for CMV reactivation. Ten patients received bone marrow, and eleven patients received peripheral blood stem cells. All patients received foscarnet prophylaxis to study side effects, incidence of CMV reactivation, CMV disease, and transplant-related mortality. Foscarnet (90 mg/kg) was given every 12 h, day +11 to day +16. Thereafter, foscarnet (90 mg/kg) was given once per day, three times per week until day +60. The incidence of CMV reactivation detected by antigenemia (pp65 antigen) or PCR was 23.8% (5 of 21 patients). Two patients developed CMV disease and one patient died of CMV-pneumonia. Seventeen patients (81%) reported severe side effects, such as gastrointestinal disturbance, headache, and urethritis. In eight patients (38%), the dose of foscarnet had to be reduced and, in six patients (28.5%), foscarnet application was discontinued because of side effects. Compared with other groups, we believe that the potential benefit of foscarnet administration in this early setting is outweighed by the risks of severe toxicity. Received: 24 June 1999 / Accepted: 25 February 2000     

Acute kidney injury after allogeneic hematopoietic stem cell transplantation – Predictors and survival impact: A single center retrospective study

Introduction and objectivesAcute kidney injury (AKI) is a frequent complication of hematopoietic stem cell transplantation (HSCT) and appears to be linked to increased morbidity and mortality. The aim of this study was to evaluate the incidence, etiology, predictors and survival impact of early AKI in the post-allogeneic HSCT setting.Patients and methodsWe performed a retrospective single center study that included 155 allogeneic transplant procedures from June 2017 through September 2019.ResultsAKI was observed in 50 patients (32%). In multivariate analysis, age (OR 31.55, 95% CI [3.42; 290.80], p = 0.002), evidence of disease at the time of transplant (OR 2.54, 95% CI [1.12; 5.75], p = 0.025), cytomegalovirus reactivation (OR 5.77, 95% CI [2.43; 13.72], p < 0.001) and hospital stay >35 days (OR 2.66, 95% CI [1.08; 6.52], p = 0.033) were independent predictors for AKI. Increasing age (HR 1.02, 95% CI [1.00; 1.04], p = 0.029), increasing length of hospital stay (HR 1.02, 95% CI [1.01; 1.03], p = 0.002), matched unrelated reduced intensity conditioning HSCT (HR 1.91, 95% CI [1.10; 3.33], p = 0.022), occurrence of grade III/IV acute graft-versus-host disease (HR 2.41, 95% CI [1.15; 5.03], p = 0.019) and need for mechanical ventilation (HR 3.49, 95% CI [1.54; 7.92], p = 0.003) predicted an inferior survival in multivariate analysis. Early AKI from any etiology was not related to worse survival.ConclusionPatients submitted to HSCT are at an increased risk for AKI, which etiology is often multifactorial. Due to AKI incidence, specialized nephrologist consultation as part of the multidisciplinary team might be of benefit.     

Μanagement of patients with hepatitis B and C before and after liver and kidney transplantation

New nucleos(t)ide analogues(NAs) with high genetic barrier to hepatitis B virus(HBV) resistance(such as entecavir, tenofovir) have improved the prognosis of patients with HBV decompensated cirrhosis and have prevented HBV recurrence after liver transplantation(LT). NAs are considered the most proper approach for HBV infection in patients under renal replacement therapy but their doses should be adjusted according to the patient's creatinine clearance. In addition, physi-cians should be aware of the potential nephrotoxicity. However, patients with chronic hepatitis C and decom-pensated cirrhosis can receive only one therapeutic option before LT, as well as for Hepatitis C virus(HCV) recurrence after LT, which is the combination of sub-cutaneous Peg-IFN and ribavirin. Generally, therapy for HCV after renal transplantation should be avoided. Although the optimal antiviral therapy for HCV infec-tion has not been established, attention has turned to a new, oral direct acting antiviral treatment which marks a promising strategy in prognosis and in amelioration of these diseases.     

How and when should we monitor chimerism after allogeneic stem cell transplantation?

Summary:Chimerism analysis has become an important tool for the peri-transplant surveillance of engraftment. It offers the possibility to realize impending graft rejection and can serve as an indicator for the recurrence of the underlying malignant or nonmalignant disease. Most recently, these investigations have become the basis for treatment intervention, for example, to avoid graft rejection, to maintain engraftment and to treat imminent relapse by pre-emptive immunotherapy. This invited review focuses on the clinical implications of characterization of hematopoietic chimerism in stem cell transplantation.     

Prolonged QT and cardiac arrest after heart transplantation: inherited or acquired?

The long QT syndrome is an inherited arrhythmogenic disease characterized by prolongation of QT interval, syncope, and sudden cardiac death because of ventricular tachycardia, mainly in the form of Torsades de Pointes. We present an unusual case of prolonged QT interval and cardiac arrest caused by Torsades de Pointes in the early phase after orthotopic heart transplant.     

Kidney dysfunction after hematopoietic cell transplantation—Etiology,management, and perspectives

Kidney dysfunction is a common complication of hematopoietic cell transplantation (HCT) with proven negative impact on early and long-term mortality. Causes of this complication are diverse, usually overlapping, and poorly understood. Therefore, management implicates multidirectional investigations and simultaneous treatment of suspected causes. The etiology is frequently unconfirmed due to a lack of specific markers and prevalence of contraindications to renal biopsy among HCT recipients. Herein, we provide a summary of etiology and propose an algorithm for evaluation of kidney injury after HCT. We also map out the most urgent areas for research that aim to identify patients at risk of severe renal injury and develop nephroprotective strategies.     

Postoperative complications as a predictor for survival after liver transplantation – proposition of a prognostic score

Background

Liver transplantation is major surgery with a high risk of complications. Existing scoring systems for evaluating complications after surgery are not specific for liver transplantation. Nor are they designed to evaluate the relation to recipient survival or graft loss. We wished to uncover the relation between postoperative complications and one-year risk of death or retransplantation, and to develop a prognostic score for complications based on our findings.