Disorders of potassium homeostasis after kidney transplantation

Disturbances of potassium balance are often encountered when managing kidney transplant recipients (KTR). Both hyperkalemia and hypokalemia may present either as medical emergencies or chronic outpatient abnormalities. Despite the high incidence of hyperkalemia and its potential life-threatening implications, consensus on its management in KTR is lacking. Hypokalemia in KTR is also well-described, although it is given less attention by clinicians compared to hyperkalemia. This article discusses the etiology, pathophysiology and management of both types of potassium disorders in KTR. Once any emergent situation has been corrected, treatment approaches include correcting insulin deficiency if present, adjusting non-immunosuppressive and immunosuppressive medications, eliminating or supplementing potassium as needed, and dietary counselling. Although commonly of multifactorial etiology, ascertaining the specific cause in a particular patient will help guide successful management. Monitoring KTR through regular laboratory testing is essential to detect serious disturbances in potassium balance since patients are often asymptomatic.

Matched pair analysis of the effect of longer hypothermic machine perfusion time on kidney transplant outcomes

BACKGROUND

Hypothermic machine perfusion (HMP) has demonstrated benefits in terms of early kidney transplant function compared to static cold storage. While longer preservation times have shown detrimental effects, a previous paired study indicated that longer pump times (the second kidney in a pair) might lead to improved outcomes.

AIM

To revisit the prior paired study's somewhat unexpected results by reviewing our program's experience.

METHODS

A total of 61 pairs of transplant recipients who received kidneys from the same donor (2012-2021) were analyzed. Patients were divided into two groups depending on whether they were transplanted first (K1) or second (K2). Therefore, the patients in each pair had identical donor characteristics, except for time on the pump. Statistical analyses included Kaplan-Meyer analysis and paired tests, including McNemar's test, student's paired t-test, or Wilcoxon's test, as appropriate.

RESULTS

The two groups of recipients had similar demographics (age, body mass index, diabetes, time on dialysis, sensitization and retransplants). Cold ischemic times for K1 and K2 were 8.9 (95%CI: 7.9, 9.8) and 14.7 hours (13.7, 15.8) (P < 0.0001), respectively. Overall, K2 had a higher rate of freedom from biopsy-proven acute rejection at 1 year (P = 0.015). Delayed graft function was less common in K2, 12/61 (20%) than in K1, 20/61 (33%) (P = 0.046). Finally, K2 showed a higher graft survival than K1 (P = 0.023).

CONCLUSION

Our results agree with a previous study that suggested possible advantages to longer pump times. Both studies should encourage further research into HMP's potential anti-inflammatory effect.

Donor hepatectomy time and liver transplantation outcomes: An opportunity that cannot be dismissed

The probability of developing primary dysfunction (PD) is a function of the probability of ischemia/reperfusion (I/R) injury. The probability of I/R injury in turn, is a function of several donor and transplantation process variables, among which is ischemia time. Custodio et al studied the duration of a special type of warm ischemia and showed, contrary to what is known, that a longer duration is not statistically different from a shorter one in PD development. This finding opens the door to the unforeseen opportunity of training fellows in performing hepatectomies, since the duration will not jeopardize liver transplant outcomes, albeit with some precautions.

SIMAP500: A novel risk score to identify recipients at higher risk of hepatocellular carcinoma recurrence following liver transplantation

BACKGROUND

Recurrence of hepatocellular carcinoma (HCC) following liver transplantation (LT) has a devastating influence on recipients’ survival; however, the risk of recurrence is not routinely stratified. Risk stratification is vital with a long LT waiting time, as that could influence the recurrence despite strict listing criteria.

AIM

This study aims to identify predictors of recurrence and develop a novel risk prediction score to forecast HCC recurrence following LT.

METHODS

A retrospective review of LT for HCC recipients at University Hospitals Birmingham between July 2011 and February 2020. Univariate and multivariate analyses were performed to identify recurrence predictors, based on which the novel SIMAP500 (satellite nodules, increase in size, microvascular invasion, AFP > 500, poor differentiation) risk score was proposed.

RESULTS

234 LTs for HCC were performed with a median follow-up of 5.3 years. Recurrence developed in 25 patients (10.7%). On univariate analyses, RETREAT score > 3, α-fetoprotein (AFP) at listing 100-500 and > 500, bridging, increased tumour size between imaging at the listing time and explant histology, increase in the size of viable tumour between listing and explant, presence of satellite nodules, micro- and macrovascular invasion on explant and poor differentiation of tumours were significantly associated with recurrence, based on which, the SIMAP500 risk score is proposed. The SIMAP500 demonstrated an excellent predictive ability (c-index = 0.803) and outperformed the RETREAT score (c-index = 0.73). SIMAP500 is indicative of the time to disease recurrence.

CONCLUSION

SIMAP500 risk score identifies the LT recipients at risk of HCC recurrence. Risk stratification allows patient-centric post-transplant surveillance programs. Further validation of the score is recommended.

Statin, aspirin and metformin use and risk of hepatocellular carcinoma related outcomes following liver transplantation: A retrospective study

BACKGROUND

Liver transplantation (LT) is a potentially curative therapy for patients with hepatocellular carcinoma (HCC). HCC-recurrence following LT is associated with reduced survival. There is increasing interest in chemoprophylaxis to improve HCC-related outcomes post-LT.

AIM

To investigate whether there is any benefit for the use of drugs with proposed chemoprophylactic properties against HCC, and patient outcomes following LT.

METHODS

This was a retrospective study of adult patients who received Deceased Donor LT for HCC from 2005-2022, from a single Australian centre. Drug use was defined as statin, aspirin or metformin therapy for ≥ 29 days, within 24 months post-LT. A cox proportional-hazards model with time-dependent covariates was used for survival analysis. Outcome measures were the composite-endpoint of HCC-recurrence and all-cause mortality, HCC-recurrence and HCC-related mortality. Sensitivity analysis was performed to account for immortality time bias and statin dosing.

RESULTS

Three hundred and five patients were included in this study, with 253 (82.95%) males with a median age of 58.90 years. Aetiologies of liver disease were 150 (49.18%) hepatitis C, 73 (23.93%) hepatitis B (HBV) and 33 (10.82%) non-alcoholic fatty liver disease (NAFLD). 56 (18.36%) took statins, 51 (16.72%) aspirin and 50 (16.39%) metformin. During a median follow-up time of 59.90 months, 34 (11.15%) developed HCC-recurrence, 48 (15.74%) died, 17 (5.57%) from HCC-related mortality. Statin, aspirin or metformin use was not associated with statistically significant differences in the composite endpoint of HCC-recurrence or all-cause mortality [hazard ratio (HR): 1.16, 95%CI: 0.58-2.30; HR: 1.21, 95%CI: 0.28-5.27; HR: 0.61, 95%CI: 0.27-1.36], HCC-recurrence (HR: 0.52, 95%CI: 0.20-1.35; HR: 0.51, 95%CI: 0.14-1.93; HR 1.00, 95%CI: 0.37-2.72), or HCC-related mortality (HR: 0.32, 95%CI: 0.033-3.09; HR: 0.71, 95%CI: 0.14-3.73; HR: 1.57, 95%CI: 0.61-4.04) respectively. Statin dosing was not associated with statistically significant differences in HCC-related outcomes.

CONCLUSION

Statin, metformin or aspirin use was not associated with improved HCC-related outcomes post-LT, in a largely historical cohort of Australian patients with a low proportion of NAFLD. Further prospective, multicentre studies are required to clarify any potential benefit of these drugs to improve HCC-related outcomes.

Impact of Medicaid expansion on kidney transplantation in the State Oklahoma

BACKGROUND

There is no data evaluating the impact of Medicaid expansion on kidney transplants (KT) in Oklahoma.

AIM

To investigate the impact of Medicaid expansion on KT patients in Oklahoma.

METHODS

The UNOS database was utilized to evaluate data pertaining to adult KT recipients in Oklahoma in the pre-and post-Medicaid eras. Bivariate analysis, Kaplan Meier analysis was used to estimate, and cox proportional models were utilized.

RESULTS

There were 2758 pre- and 141 recipients in the post-Medicaid expansion era. Post-expansion patients were more often non-United States citizens (2.3% vs 5.7%), American Indian, Alaskan, or Pacific Islander (7.8% vs 9.2%), Hispanic (7.4% vs 12.8%), or Asian (2.5% vs 8.5%) (P < 0.0001). Waitlist time was shorter in the post-expansion era (410 vs 253 d) (P = 0.0011). Living donor rates, pre-emptive transplants, re-do transplants, delayed graft function rates, kidney donor profile index values, panel reactive antibodies levels, and insurance types were similar. Patients with public insurance were more frail. Despite increased early (< 6 months) rejection rates, 1-year patient and graft survival were similar. In Cox proportional hazards model, male sex, American Indian, Alaskan or Pacific Islander race, public insurance, and frailty category were independent risk factors for death at 1 year. Medicaid expansion was not associated with graft failure or patient survival (adjusted hazard ratio: 1.07; 95%CI: 0.26-4.41).

CONCLUSION

Medicaid expansion in Oklahoma is associated with increased KT access for non-White/non-Black and non-United States citizen patients with shorter wait times. 1-year graft and patient survival rates were similar before and after expansion. Medicaid expansion itself was not independently associated with graft or patient survival outcomes. Ongoing research is necessary to determine the long-term effects of Medicaid expansion.

Impact of bisphosphonate treatment on bone mineral density after kidney transplant

BACKGROUND

Mineral bone disease is associated with chronic kidney disease and persists after kidney transplantation. Immunosuppressive treatment contributes to the pathogenesis of this disease. Bisphosphonate treatments have shown positive but indefinite results.

AIM

To evaluate the effectiveness and safety of bisphosphonate treatment on post kidney transplantation bone mineral density (BMD).

METHODS

We included kidney transplant recipients (KTRs) whose BMD was measured after the operation but before the initiation of treatment and their BMD was measured at least one year later. We also evaluated the BMD of KTRs using two valid measurements after transplantation who received no treatment (control group).

RESULTS

Out of 254 KTRs, 62 (39 men) were included in the study. Bisphosphonates were initiated in 35 KTRs in total (20 men), 1.1 ± 2.4 years after operation and for a period of 3.9 ± 2.3 years while 27 (19 men) received no treatment. BMD improved significantly in KTRs who received bisphosphonate treatments (from -2.29 ± 1.07 to -1.66 ± 1.09, P < 0.0001). The control group showed a non-significant decrease in BMD after 4.2 ± 1.4 years of follow-up after surgery. Kidney function was not affected by bisphosphonate treatment. In KTRs with established osteoporosis, active treatment had a similar and significant effect on those with osteopenia or normal bone mass.

CONCLUSION

In this retrospective study of KTRs receiving bisphosphonate treatment, we showed that active treatment is effective in preventing bone loss irrespective of baseline BMD.

Kidney transplantation outcomes: Is it possible to improve when good results are falling down?

Famure et al describe that close to 50% of their patients needed early or very early hospital readmissions after their kidney transplantation. As they taught us the variables related to those outcomes, we describe eight teaching capsules that may go beyond what they describe in their article. First two capsules talk about the ideal donors and recipients we should choose for avoiding the risk of an early readmission. The third and fourth capsules tell us about the reality of cadaveric donors and recipients with comorbidities, and the way transplant physicians should choose them to maximize survival. Fifth capsule shows that any mistake can result in an early readmission, and thus, in poorer outcomes. Sixth capsule talks about economic losses of early readmissions, cost-effectiveness of transplantation, and how to improve outcomes and reduce costs by managing a risky patient-portfolio. Seventh capsule argues about knowing your risk behavior to better manage your portfolio; and Eighth capsule about the importance of the center experience in transplanting complex patients. We finish with some lessons of the importance of the transplantation process and the collaboration with other disciplines in order to prevent the conditions that lead to early readmissions.

Challenges related to clinical decision-making in hepatocellular carcinoma recurrence post-liver transplantation: Is there a hope?

Hepatocellular carcinoma (HCC) is a common liver malignancy and represents a serious cause of cancer-related mortality and morbidity. One of the favourable curative surgical therapeutic options for HCC is liver transplantation (LT) in selected patients fulfilling the known standard Milan/University of California San Francisco criteria which have shown better outcomes and longer-term survival. Despite careful adherence to the strict HCC selection criteria for LT in different transplant centres, the recurrence rate still occurs which could negatively affect HCC patients’ survival. Hence HCC recurrence post-LT could predict patients’ survival and prognosis, depending on the exact timing of recurrence after LT (early or late), and whether intra/extrahepatic HCC recurrence. Several factors may aid in such a complication, particularly tumour-related criteria including larger sizes, higher grades or poor tumour differentiation, microvascular invasion, and elevated serum alpha-fetoprotein. Therefore, managing such cases is challenging, different therapeutic options have been proposed, including curative surgical and ablative treatments that have shown better outcomes, compared to the palliative locoregional and systemic therapies, which may be helpful in those with unresectable tumour burden. To handle all these issues in our review.

Recipient functional status impacts on short and long-term intestinal transplant outcomes in United States adults

BACKGROUND

Recipient functional status prior to transplantation has been found to impact post-transplant outcomes in heart, liver and kidney transplants. However, information on how functional status, before and after transplant impacts post-transplant survival outcomes is lacking.

AIM

To investigate the impact of recipient functional status on short and long term intestinal transplant outcomes in United States adults.

METHODS

We conducted a retrospective cohort study on 1254 adults who underwent first-time intestinal transplantation from 2005 to 2022. The primary outcome was mortality. Using the Karnofsky Performance Status, functional impairment was categorized as severe, moderate and normal. Analyses were conducted using Kaplan-Meier curves and multivariable Cox regression.

RESULTS

The median age was 41 years, majority (53.4%) were women. Severe impairment was present in 28.3% of recipients. The median survival time was 906.6 days. The median survival time was 1331 and 560 days for patients with normal and severe functional impairment respectively. Recipients with severe impairment had a 56% higher risk of mortality at one year [Hazard ratio (HR) = 1.56; 95%CI: 1.23–1.98; P < 0.001] and 58% at five years (HR = 1.58; 95%CI: 1.24–2.00; P < 0.001) compared to patients with no functional impairment. Recipients with worse functional status after transplant also had poor survival outcomes.

CONCLUSION

Pre- and post-transplant recipient functional status is an important prognostic indicator for short- and long-term intestinal transplant outcomes.

Management of cytomegalovirus infection after liver transplantation

Cytomegalovirus (CMV) infection is one of the primary causes of morbidity and mortality following liver transplantation (LT). Based on current worldwide guidelines, the most effective strategies for avoiding post-transplant CMV infection are antiviral prophylaxis and pre-emptive treatment. CMV- IgG serology is the established technique for pretransplant screening of both donors and recipients. The clinical presentation of CMV infection and disease exhibits variability, prompting clinicians to consistently consider this possibility, particularly within the first year post-transplantation or subsequent to heightened immunosuppression. At annual symposia to discuss CMV prevention and how treatment outcomes can be improved, evidence on the incorporation of immune functional tests into clinical practice is presented, and the results of studies with new antiviral treatments are evaluated. Although there are ongoing studies on the use of letermovir and maribavir in solid organ transplantation, a consensus reflected in the guidelines has not been formed. Determining the most appropriate strategy at the individual level appears to be the key to enhancing outcomes. Although prevention strategies reduce the risk of CMV disease, the disease can still occur in up to 50% of high-risk patients. A balance between the risk of infection and disease development and the use of immunosuppressants must be considered when talking about the proper management of CMV in solid organ transplant recipients. The objective of this study was to establish a comprehensive framework for the management of CMV in patients who have had LT.

Tuberculosis in kidney transplant candidates and recipients

Tuberculosis (TB) is the leading cause of infectious mortality and morbidity in the world, second only to coronavirus disease 2019. Patients with chronic kidney disease and kidney transplant recipients are at a higher risk of developing TB than the general population. Active TB is difficult to diagnose in this population due to close mimics. All transplant candidates should be screened for latent TB infection and given TB prophylaxis. Patients who develop active TB pre- or post-transplantation should receive multidrug combination therapy of antitubercular therapy for the recommended duration with optimal dose modification as per glomerular filtration rate.

Exercise as a modality to improve heart transplantation-related functional impairments: An article review

Heart transplantation (HT), the treatment choice of advanced heart failure patients, is proven effective in increasing the survival and functional status of the recipients. However, compared to normal controls, functional status is lower in HT recipients. Exercise given in cardiac rehabilitation has been shown to improve exercise capacity as measured with peak oxygen uptake (VO2 peak) and muscle strength after completion of the program and cessation of exercise results in loss of exercise benefits. Several factors related to cardiac denervation and the use of immunosuppressive agents in HT recipients result in functional impairments including cardiovascular, pulmonary, exercise capacity, psychological, and quality of life (QoL) problems. High-intensity interval training (HIIT) is the most common type of exercise used in HT recipients and given as a hospital-based program. Improvement of functional impairments was found to have occurred due to primarily musculoskeletal adaptations through improvement of muscle structure and aerobic capacity and cardiovascular adaptations. In general, exercise given after transplantation improved VO2 peak significantly and improvement was better in the HIIT group compared to moderate intensity continuous training or no-exercise groups. Improvement of QoL was ascribed to improvement of exercise capacity, symptoms, pulmonary function, physical capacity improvement, anxiety, and depression.

Evolution of heart transplant donor characteristics in the 21st century: A United States single center’s experience

Despite a record setting number of heart transplants performed annually, the national donor shortage continues to plague transplant teams across the United States. Here we describe the barriers to adaptation of numerous “non-traditional” orthotopic heart transplant donor characteristics including donors with hepatitis C virus, those meeting criteria for donation after cardiac death, donors with coronavirus disease 19 infection, donors with the human immunodeficiency virus, and grafts with left ventricular systolic dysfunction. Our center’s objective was to increase our transplant volume by expanding our donor pool from “traditional” donors to these “non-traditional” donors. We detail how medical advances such as certain laboratory studies, pharmacologic interventions, and organ care systems have allowed our center to expand the donor pool thereby increasing transplantation volume without adverse effects on outcomes.

Impact of hepatitis B immunoglobulin mode of administration on treatment experiences of patients after liver transplantation: Results from an online survey

BACKGROUND

Hepatitis B immunoglobulin (HBIG) in combination with a potent nucleos(t)ide analog is considered the standard of care for prophylaxis against hepatitis B virus (HBV) reinfection after liver transplantation for HBV-associated disease.

AIM

To evaluate patients’ satisfaction, preferences, and requirements for subcutaneous (SC), intramuscular (IM), and intravenous (IV) HBIG treatments.

METHODS

A self-completion, cross-sectional, online, 22-question survey was conducted to examine perceptions and satisfaction with current HBIG treatment in adults receiving HBIG treatment following liver transplantation for HBV-associated disease in France, Italy, and Turkey. Hypothetical HBIG products with different administration modes were evaluated using target product profile assessment and a conjoint (trade-off) exercise.

RESULTS

Ninety patients were enrolled; 32%, 17%, and 51% were SC, IM, and IV HBIG users, respectively. Mean duration of treatment was 36.2 months. SC HBIG had the least negative impact on emotional well-being and social life and was perceived as the most convenient, easiest to administer, least painful, and had the highest self-rating of treatment compliance. More IM HBIG users than SC or IV HBIG users reported that administration frequency was excessive (67%, 28%, and 28%, respectively). In the target product profile assessment, 76% of patients were likely to use hypothetical SC HBIG. In the conjoint exercise, administration route, frequency, and duration were key drivers of treatment preferences.

CONCLUSION

Ease, frequency, duration, and side effects of HBIG treatment administration were key drivers of treatment preferences, and SC HBIG appeared advantageous over IM and IV HBIG for administration ease, convenience, and pain. A hypothetical SC HBIG product elicited a favorable response. Patient demographics, personal preferences, and satisfaction with HBIG treatment modalities may influence long-term treatment compliance.

Genitourinary tumors and liver transplantation: A comprehensive review

Liver transplantation is as a crucial therapeutic option for patients with end-stage liver disease, but the persistent organ shortage emphasizes a need to explore unconventional donor sources, including individuals with a history of malignancies. This review investigates the viability of liver donation from individuals with current or past genitourinary malignancies, focusing on renal, prostate and urinary bladder cancers. The rising incidence of urogenital malignancies among potential donors is thought to result from increasing donor age. Analysis of transmission risks reveals low rates of donor-derived cancer transmission, particularly for early-stage renal and prostate cancers. Recipients with a history of genitourinary malignancy pose complex challenges regarding post-transplant immunosuppression and cancer recurrence. Nonetheless, the evidence suggests acceptable outcomes can be achieved with careful patient selection and tailored management strategies. Recommendations for pre-transplant evaluation and post-transplant surveillance are discussed, highlighting the need for individualized approaches in this patient population. Further prospective studies are warranted to refine guidelines and optimize outcomes in liver transplantation for patients with genitourinary malignancies.

Does the use of double hormone replacement therapy for trauma patient organ donors improve organ recovery for transplant

BACKGROUND

With an ongoing demand for transplantable organs, optimization of donor management protocols, specifically in trauma populations, is important for obtaining a high yield of viable organs per patient. Endocrine management of brain-dead potential organ donors (BPODs) is controversial, leading to heterogeneous clinical management approaches. Previous studies have shown that when levothyroxine was combined with other treatments, including steroids, vasopressin, and insulin, BPODs had better organ recovery and survival outcomes were increased for transplant recipients.

AIM

To determine if levothyroxine use in combination with steroids in BPODs increased the number of organs donated in trauma patients.

METHODS

A retrospective review of adult BPODs from a single level 1 trauma center over ten years was performed. Exclusion criteria included patients who were not solid organ donors, patients who were not declared brain dead (donation after circulatory death), and patients who did not receive steroids in their hospital course. Levothyroxine and steroid administration, the number of organs donated, the types of organs donated, and demographic information were recorded. Univariate analyses were performed with P < 0.05 considered to be statistically significant.

RESULTS

A total of 88 patients met inclusion criteria, 69 (78%) of whom received levothyroxine and steroids (ST/LT group) vs 19 (22%) receiving steroids without levothyroxine (ST group). No differences were observed between the groups for gender, race, pertinent injury factors, age, or other hormone therapies used (P > 0.05). In the ST/LT group, 68.1% (n = 47) donated a high yield (3-5) of organ types per donor compared to 42.1% (n = 8) in the ST group (P = 0.038). There was no difference in the total number of organ types donated between the groups (P = 0.068).

CONCLUSION

This study suggests that combining levothyroxine and steroid administration increases high-yield organ donation per donor in BPODs in the trauma patient population. Limitations to this study include the retrospective design and the relatively small number of organ donors who met inclusion criteria. This study is unique in that it mitigates steroid administration as a confounding variable and focuses specifically on the adjunctive use of levothyroxine.

Frequency of and reasons behind non-listing in adult patients referred for liver transplantation: Results from a retrospective study

BACKGROUND

Few studies have evaluated the frequency of and the reasons behind the refusal of listing liver transplantation candidates.

AIM

To assess the ineligibility rate for liver transplantation and its motivations.

METHODS

A single-center retrospective study was conducted on adult patients which entailed a formal multidisciplinary assessment for liver transplantation eligibility. The predictors for listing were evaluated using multivariable logistic regression.

RESULTS

In our center, 314 patients underwent multidisciplinary work-up before liver transplantation enlisting over a three-year period. The most frequent reasons for transplant evaluation were decompensated cirrhosis (51.6%) and hepatocellular carcinoma (35.7%). The non-listing rate was 53.8% and the transplant rate was 34.4% for the whole cohort. Two hundred and five motivations for ineligibility were collected. The most common contraindications were psychological (9.3%), cardiovascular (6.8%), and surgical (5.9%). Inappropriate or premature referral accounted for 76 (37.1%) cases. On multivariable analysis, a referral from another hospital (OR: 2.113; 95%CI: 1.259-3.548) served as an independent predictor of non-listing.

CONCLUSION

A non-listing decision occurred in half of our cohort and was based on an inappropriate or premature referral in one case out of three. The referral from another hospital was taken as a strong predictor of non-listing.

Transarterial embolization is an acceptable bridging therapy to hepatocellular carcinoma prior to liver transplantation

BACKGROUND

Hepatocellular carcinoma (HCC) is an aggressive malignant neoplasm that requires liver transplantation (LT). Despite patients with HCC being prioritized by most organ allocation systems worldwide, they still have to wait for long periods. Locoregional therapies (LRTs) are employed as bridging therapies in patients with HCC awaiting LT. Although largely used in the past, transarterial embolization (TAE) has been replaced by transarterial chemoembolization (TACE). However, the superiority of TACE over TAE has not been consistently shown in the literature.

AIM

To compare the outcomes of TACE and TAE in patients with HCC awaiting LT.

METHODS

All consecutive patients with HCC awaiting LT between 2011 and 2020 at a single center were included. All patients underwent LRT with either TACE or TAE. Some patients also underwent percutaneous ethanol injection (PEI), concomitantly or in different treatment sessions. The choice of LRT for each HCC nodule was determined by a multidisciplinary consensus. The primary outcome was waitlist dropout due to tumor progression, and the secondary outcome was the occurrence of adverse events. In the subset of patients who underwent LT, complete pathological response and post-transplant recurrence-free survival were also assessed.

RESULTS

Twelve (18.5%) patients in the TACE group (only TACE and TACE + PEI; n = 65) and 3 (7.9%) patients in the TAE group (only TAE and TAE + PEI; n = 38) dropped out of the waitlist due to tumor progression (P log-rank test = 0.29). Adverse events occurred in 8 (12.3%) and 2 (5.3%) patients in the TACE and TAE groups, respectively (P = 0.316). Forty-eight (73.8%) of the 65 patients in the TACE group and 29 (76.3%) of the 38 patients in the TAE group underwent LT (P = 0.818). Among these patients, complete pathological response was detected in 7 (14.6%) and 9 (31%) patients in the TACE and TAE groups, respectively (P = 0.145). Post-LT, HCC recurred in 9 (18.8%) and 4 (13.8%) patients in the TACE and TAE groups, respectively (P = 0.756). Posttransplant recurrence-free survival was similar between the groups (P log-rank test = 0.71).

CONCLUSION

Dropout rates and posttransplant recurrence-free survival of TAE were similar to those of TACE in patients with HCC. Our study reinforces the hypothesis that TACE is not superior to TAE as a bridging therapy to LT in patients with HCC.

Controversies regarding transplantation of mesenchymal stem cells

Mesenchymal stem cells (MSCs) have tantalized regenerative medicine with their therapeutic potential, yet a cloud of controversies looms over their clinical transplantation. This comprehensive review navigates the intricate landscape of MSC controversies, drawing upon 15 years of clinical experience and research. We delve into the fundamental properties of MSCs, exploring their unique immunomodulatory capabilities and surface markers. The heart of our inquiry lies in the controversial applications of MSC transplantation, including the perennial debate between autologous and allogeneic sources, concerns about efficacy, and lingering safety apprehensions. Moreover, we unravel the enigmatic mechanisms surrounding MSC transplantation, such as homing, integration, and the delicate balance between differentiation and paracrine effects. We also assess the current status of clinical trials and the ever-evolving regulatory landscape. As we peer into the future, we examine emerging trends, envisioning personalized medicine and innovative delivery methods. Our review provides a balanced and informed perspective on the controversies, offering readers a clear understanding of the complexities, challenges, and potential solutions in MSC transplantation.

Safety and efficacy of Kaffes intraductal self-expanding metal stents in the management of post-liver transplant anastomotic strictures

BACKGROUND

Endoscopic management is the first-line therapy for post-liver-transplant anastomotic strictures. Although the optimal duration of treatment with plastic stents has been reported to be 8-12 months, data on safety and duration for metal stents in this setting is scarce. Due to limited access to endoscopic retrograde cholangiopancreatography (ERCP) during the coronavirus disease 2019 pandemic in our centre, there was a change in practice towards increased usage and length-of-stay of the Kaffes biliary intraductal self-expanding stent in patients with suitable anatomy. This was mainly due to the theoretical benefit of Kaffes stents allowing for longer indwelling periods compared to the traditional plastic stents.

AIM

To compare the safety and efficacy profile of different stenting durations using Kaffes stents.

METHODS

Adult liver transplant recipients aged 18 years and above who underwent ERCP were retrospectively identified during a 10-year period through a database query. Unplanned admissions post-Kaffes stent insertion were identified manually through electronic and scanned medical records. The main outcome was the incidence of complications when stents were left indwelling for 3 months vs 6 months. Stent efficacy was calculated via rates of stricture recurrence between patients that had stenting courses for ≤ 120 d or > 120 d.

RESULTS

During the study period, a total of 66 ERCPs with Kaffes insertion were performed in 54 patients throughout their stenting course. In 33 ERCPs, the stent was removed or exchanged on a 3-month interval. No pancreatitis, perforations or deaths occurred. Minor post-ERCP complications were similar between the 3-month (abdominal pain and intraductal migration) and 6-month (abdominal pain, septic shower and embedded stent) groups - 6.1% vs 9.1% respectively, P = 0.40. All strictures resolved at the end of the stenting course, but the stenting course was variable from 3 to 22 months. The recurrence rate for stenting courses lasting for up to 120 d was 71.4% and 21.4% for stenting courses of 121 d or over (P = 0.03). There were 28 patients that were treated with a single ERCP with Kaffes, 21 with removal after 120 d and 7 within 120 d. There was a significant improvement in stricture recurrence when the Kaffes was removed after 120 d when a single ERCP was used for the entire stenting course (71.0% vs 10.0%, P = 0.01).

CONCLUSION

Utilising a single Kaffes intraductal fully-covered metal stent for at least 4 months is safe and efficacious for the management of post-transplant anastomotic strictures.

Impact of payment source, referral site, and place of residence on outcomes after allogeneic transplantation in Mexico

BACKGROUND

The impact of social determinants of health in allogeneic transplant recipients in low- and middle-income countries is poorly described. This observational study analyzes the impact of place of residence, referring institution, and transplant cost coverage (out-of-pocket vs government-funded vs private insurance) on outcomes after allogeneic hematopoietic stem cell transplantation (alloHSCT) in two of Mexico's largest public and private institutions.

AIM

To evaluate the impact of social determinants of health and their relationship with outcomes among allogeneic transplant recipients in Mexico.

METHODS

In this retrospective cohort study, we included adolescents and adults ≥ 16 years who received a matched sibling or haploidentical transplant from 2015-2022. Participants were selected without regard to their diagnosis and were sourced from both a private clinic and a public University Hospital in Mexico. Three payment groups were compared: Out-of-pocket (OOP), private insurance, and a federal Universal healthcare program "Seguro Popular". Outcomes were compared between referred and institution-diagnosed patients, and between residents of Nuevo Leon and out-of-state. Primary outcomes included overall survival (OS), categorized by residence, referral, and payment source. Secondary outcomes encompassed early mortality, event-free-survival, graft-versus-host-relapse-free survival, and non-relapse-mortality (NRM). Statistical analyses employed appropriate tests, Kaplan-Meier method, and Cox proportional hazard regression modeling. Statistical software included SPSS and R with tidycmprsk library.

RESULTS

Our primary outcome was overall survival. We included 287 patients, n = 164 who lived out of state (57.1%), and n = 129 referred from another institution (44.9%). The most frequent payment source was OOP (n = 139, 48.4%), followed by private insurance (n = 75, 26.1%) and universal coverage (n = 73, 25.4%). No differences in OS, event-free-survival, NRM, or graft-versus-host-relapse-free survival were observed for patients diagnosed locally vs in another institution, nor patients who lived in-state vs out-of-state. Patients who covered transplant costs through private insurance had the best outcomes with improved OS (median not reached) and 2-year cumulative incidence of NRM of 14% than patients who covered costs OOP (Median OS and 2-year NRM of 32%) or through a universal healthcare program active during the study period (OS and 2-year NRM of 19%) (P = 0.024 and P = 0.002, respectively). In a multivariate analysis, payment source and disease risk index were the only factors associated with overall survival.

CONCLUSION

In this Latin-American multicenter study, the site of residence or referral for alloHSCT did not impact outcomes. However, access to healthcare coverage for alloHSCT was associated with improved OS and reduced NRM.

Expanding the liver donor pool worldwide with hepatitis C infected livers, is it the time?

Liver transplantation (LT) provides a life-saving option for cirrhotic patients with complications and hepatocellular carcinoma. Despite the increasing number of liver transplants performed each year, the number of LT candidates on the waitlist remains unchanged due to an imbalance between donor organ supply and the demand which increases the waitlist time and mortality. Living donor liver transplant had a great role in increasing the donor pool and shortened waitlist time for LT candidates. Nevertheless, further strategies can be implemented to increase the pool of potential donors in deceased donor LT, such as reducing the rate of organ discards. Utilizing hepatitis C virus (HCV) seropositive liver grafts is one of the expanded donor organ criteria. A yearly increase of hundreds of transplants is anticipated as a result of maximizing the utilization of HCV-positive organs for HCV-negative recipients. Direct-acting antiviral therapy's efficacy has revolutionized the treatment of HCV infection and the use of HCV-seropositive donors in transplantation. The American Society of Transplantation advises against performing transplants from HCV-infected liver donors (D+) into HCV-negative recipient (R-) unless under Institutional Review Board-approved study rules and with full informed consent of the knowledge gaps associated with such transplants. Proper selection of patients to be transplanted with HCV-infected grafts and confirming their access to direct-acting antivirals if needed is important. National and international consensuses are needed to regulate this process to ensure the maximum benefit and the least adverse events.

Hyperacute experimental model of rat lung transplantation using a coronary shunt cannula

BACKGROUND

Lung transplantation is a well-established treatment of end-stage lung disease. A rodent model is an inexpensive way to collect biological data from a living model after lung transplantation. However, mastering the surgical technique takes time owing to the small organ size.

AIM

To conduct rat lung transplantation using a shunt cannula (SC) or modified cannula (MC) and assess their efficacy.

METHODS

Rat lung transplantation was performed in 11 animals in the SC group and 12 in the MC group. We devised a method of rat lung transplantation using a coronary SC for coronary artery bypass surgery as an anastomosis of pulmonary arteriovenous vessels and bronchioles. The same surgeon performed all surgical procedures in the donor and recipient rats without using a magnifying glass. The success rate of lung transplantation, operating time, and PaO2 values were compared after 2-h reperfusion after transplantation.

RESULTS

Ten and 12 lungs were successfully transplanted in the SC and MC groups, respectively. In the SC group, one animal had cardiac arrest within 1 h after reperfusion owing to bleeding during pulmonary vein anastomosis. The operating time for the removal of the heart-lung block from the donor and preparation of the left lung graft was 26.8 ± 2.3 and 25.7 ± 1.3 min in the SC and MC groups, respectively (P = 0.21). The time required for left lung transplantation in the recipients was 37.5 ± 2.8 min and 35.9 ± 1.4 min in the SC and MC groups, respectively (P = 0.12). PaO2 values at 2 h after reperfusion were 456.2 ± 25.5 and 461.2 ± 21.5 mmHg in the SC and MC groups, respectively (P = 0.63), without difference between the groups.

CONCLUSION

A hyperacute rat lung transplantation model using a coronary SC was created using a simple technique. The MC was inexpensive, easy to prepare, and simple to operate.

Incidence, risk factors and clinical outcome of multidrug-resistant organisms after heart transplantation

BACKGROUND

Transplant recipients commonly harbor multidrug-resistant organisms (MDROs), as a result of frequent hospital admissions and increased exposure to antimicrobials and invasive procedures.

AIM

To investigate the impact of patient demographic and clinical characteristics on MDRO acquisition, as well as the impact of MDRO acquisition on intensive care unit (ICU) and hospital length of stay, and on ICU mortality and 1-year mortality post heart transplantation.

METHODS

This retrospective cohort study analyzed 98 consecutive heart transplant patients over a ten-year period (2013-2022) in a single transplantation center. Data was collected regarding MDROs commonly encountered in critical care.

RESULTS

Among the 98 transplanted patients (70% male), about a third (32%) acquired or already harbored MDROs upon transplantation (MDRO group), while two thirds did not (MDRO-free group). The prevalent MDROs were Acinetobacter baumannii (14%), Pseudomonas aeruginosa (12%) and Klebsiella pneumoniae (11%). Compared to MDRO-free patients, the MDRO group was characterized by higher body mass index (P = 0.002), higher rates of renal failure (P = 0.017), primary graft dysfunction (10% vs 4.5%, P = 0.001), surgical re-exploration (34% vs 14%, P = 0.017), mechanical circulatory support (47% vs 26% P = 0.037) and renal replacement therapy (28% vs 9%, P = 0.014), as well as longer extracorporeal circulation time (median 210 vs 161 min, P = 0.003). The median length of stay was longer in the MDRO group, namely ICU stay was 16 vs 9 d in the MDRO-free group (P = 0.001), and hospital stay was 38 vs 28 d (P = 0.006), while 1-year mortality was higher (28% vs 7.6%, log-rank-χ 2: 7.34).

CONCLUSION

Following heart transplantation, a predominance of Gram-negative MDROs was noted. MDRO acquisition was associated with higher complication rates, prolonged ICU and total hospital stay, and higher post-transplantation mortality.