Design and Methods of the Korean Organ Transplantation Registry

International Travel for Organ Transplantation: A Survey of Professional Experiences and Attitudes Toward Data Collection and Reporting

Background

Lack of data regarding international travel for organ transplantation (ITOT) hampers efforts to evaluate, understand, and respond to trends in ITOT activities, such as those suggestive of organ trafficking or "transplant tourism." This study aimed to assess transplant professionals' experience of ITOT and their attitudes toward reporting ITOT data to a global registry.

Methods

An international cross-sectional anonymous survey of transplant professionals was conducted online (from October to December 2022). The English language questionnaire assessed professional experiences in providing care to individuals who had traveled to or from a country for living donation or transplantation, and attitudes toward reporting of ITOT data. Data were analyzed with descriptive statistics.

Results

Two hundred thirty-nine individuals from 68 countries completed the entire questionnaire, of whom 79% had provided care for ≥1 patient who had traveled internationally for donation or transplantation. Of these, 60.8% of individuals (n = 115) had cared for ≥1 person who engaged in ITOT between 2019 and 2022, with the most recent case experiences involving 89 countries and 157 unique routes of international travel. Predominant concerns regarding reporting of ITOT data to a global registry related to prevention of harm and protection of patient privacy; most (52.7%; n = 126) respondents expressed a preference for anonymous reporting of ITOT data.

Conclusions

ITOT is a global phenomenon and transplant professionals' experience with ITOT cases is more common than anticipated. Systems for the collection of ITOT activity data should be carefully designed to address potential ethical concerns of transplant professionals which may influence reporting practices.

Outcomes and Risk Factors for Liver Transplantation Using Graft-to-Recipient Weight Ratio Less Than 0.8 Graft From Living Donors: Multicentric Cohort Study

OBJECTIVE

To compare graft survival after living donor liver transplantation (LDLT) in patients receiving graft-to-recipient weight ratio (GRWR) <0.8 versus GRWR≥0.8 grafts and identify risk factors for graft loss using GRWR<0.8 grafts.

BACKGROUND

Favorable outcomes after LDLT using GRWR<0.8 grafts were recently reported; however, these results have not been validated using multicenter data.

METHODS

This multicentric cohort study included 3450 LDLT patients. Graft survival was compared between 1:3 propensity score-matched groups and evaluated using various Cox models in the entire population. Risk factors for graft loss with GRWR<0.8 versus GRWR≥0.8 grafts were explored within various subgroups using interaction analyses, and outcomes were stratified according to the number of risk factors.

RESULTS

In total, 368 patients (10.7%) received GRWR<0.8 grafts (GRWR<0.8 group), whereas 3082 (89.3%) received GRWR≥0.8 grafts (GRWR≥0.8 group). The 5-year graft survival rate was significantly lower with GRWR<0.8 grafts than with GRWR≥0.8 grafts (85.2% vs 90.1%, P =0.013). Adjusted hazard ratio for graft loss using GRWR<0.8 grafts in the entire population was 1.66 (95% CI: 1.17-2.35, P =0.004). Risk factors exhibiting significant interactions with GRWR<0.8 for graft survival were age ≥60 years, Model for End-stage Liver Disease score ≥15, and male donor. When ≥2 risk factors were present, GRWR<0.8 grafts showed a higher risk of graft loss compared with GRWR≥0.8 graft in LDLT (hazard ratio 2.98, 95% CI: 1.79-4.88, P <0.001).

CONCLUSIONS

GRWR<0.8 graft showed inferior graft survival than controls (85.2% vs 90.1%), especially when ≥2 risk factors for graft loss (among age 60 years or above, Model for End-stage Liver Disease score ≥15, or male donor) were present.

Impact of Everolimus Initiation and Corticosteroid Weaning During Acute Phase After Heart Transplantation on Clinical Outcome: Data from the Korean Organ Transplant Registry (KOTRY)

The effect of changes in immunosuppressive therapy during the acute phase post-heart transplantation (HTx) on clinical outcomes remains unclear. This study aimed to investigate the effects of changes in immunosuppressive therapy by corticosteroid (CS) weaning and everolimus (EVR) initiation during the first year post-HTx on clinical outcomes. We analyzed 622 recipients registered in the Korean Organ Transplant Registry (KOTRY) between January 2014 and December 2021. The median age at HTx was 56 years (interquartile range [IQR], 45-62), and the median follow-up time was 3.9 years (IQR 2.0-5.1). The early EVR initiation within the first year post-HTx and maintenance during the follow-up is associated with reduced the risk of primary composite outcome (all-cause mortality or re-transplantation) (HR, 0.24; 95% CI 0.09-0.68; p < 0.001) and cardiac allograft vasculopathy (CAV) (HR, 0.39; 95% CI 0.19-0.79; p = 0.009) compared with EVR-free or EVR intermittent treatment regimen, regardless of CS weaning. However, the early EVR initiation tends to increase the risk of acute allograft rejection compared with EVR-free or EVR intermittent treatment.

The effect of donor against recipient one-way HLA mismatch on liver transplantation outcomes from a multicenter registry analysis

Donor against recipient one-way Human leukocyte antigen (HLA) mismatch (D → R one-way HLA MM) seemed strongly associated with graft-versus-host disease (GVHD). The aim of this study is to investigate the relevance of D → R one-way HLA MM in outcome of liver transplantation (LT). We retrospectively analyzed 2670 patients in Korean Organ Transplantation Registry database between April 2014 and December 2020. The patients were categorized into two groups whether D → R one-way HLA MM or not and evaluated the outcomes of LT between the two groups. 18 patients were found to be D → R one-way HLA MM. The incidence of GVHD (0.3% vs. 22.2%, p < 0.001) and mortality rate (11.6% vs. 38.9%, p = 0.003) was much higher in D → R one-way HLA MM group. D → R one-way HLA MM at 3 loci was seemed to be strongly associated with the incidence of GVHD (OR 163.3, p < 0.001), and found to be the strongest risk factor for patient death (HR 12.75, p < 0.001). Patients with D → R one-way HLA MM at 3 loci showed significantly lower overall survival (p < 0.001) but there were no significant differences in rejection-free survival and death-censored graft survival. D → R one-way HLA MM at 3 loci not only affects the overall survival of LT patients but also the incidence of GVHD.

Clinical implications of changes in metabolic syndrome status after kidney transplantation: a nationwide prospective cohort study

BACKGROUND

Metabolic syndrome (MetS) is prevalent in patients with end-stage kidney disease, and kidney transplantation is expected to modify the metabolic status. However, whether changes in metabolic status at the time of transplantation affect recipient outcomes remains unclear.

METHODS

We analyzed 4187 recipients registered in a nationwide prospective cohort from 2014 to 2020. MetS was defined as the presence of three or more components of the metabolic syndrome. Patients were classified based on the pre- and post-transplant MetS status: MetS-free, MetS-developed, MetS-recovered and MetS-persistent. Study outcomes were occurrence of death-censored graft loss and a composite of cardiovascular events and death.

RESULTS

Among recipients without pre-transplant MetS, 19.6% (419/2135) developed post-transplant MetS, and MetS disappeared in 38.7% (794/2052) of the recipients with pre-transplant MetS. Among the four groups, the MetS-developed group showed the worst graft survival rate, and the MetS-persistent group had a poorer composite event-free survival rate. Compared with the MetS-free group, the MetS-developed group was associated with an increased risk of graft loss [adjusted hazard ratio (aHR) 2.35; 95% confidence interval (CI) 1.17-4.98] and the risk of graft loss increased with increasing numbers of dysfunctional MetS components. MetS-persistent was associated with increased risks of cardiovascular events and death (aHR 2.46; 95% CI 1.12-5.63), but changes in the number of dysfunctional MetS components was not.

CONCLUSION

Kidney transplantation significantly alters the metabolic status. Newly developed MetS after transplantation was associated with an increased risk of graft loss, whereas persistent MetS exposure before and after transplantation was associated with increased risks cardiovascular events and patient survival.

International Liver Transplantation Society Global Census: First Look at Pediatric Liver Transplantation Activity Around the World

BACKGROUND

Over 16 000 children under the age of 15 died worldwide in 2017 because of liver disease. Pediatric liver transplantation (PLT) is currently the standard of care for these patients. The aim of this study is to describe global PLT activity and identify variations between regions.

METHODS

A survey was conducted from May 2018 to August 2019 to determine the current state of PLT. Transplant centers were categorized into quintile categories according to the year they performed their first PLT. Countries were classified according to gross national income per capita.

RESULTS

One hundred eight programs from 38 countries were included (68% response rate). 10 619 PLTs were performed within the last 5 y. High-income countries performed 4992 (46.4%) PLT, followed by upper-middle- (4704 [44·3%]) and lower-middle (993 [9·4%])-income countries. The most frequently used type of grafts worldwide are living donor grafts. A higher proportion of lower-middle-income countries (68·7%) performed ≥25 living donor liver transplants over the last 5 y compared to high-income countries (36%; P = 0.019). A greater proportion of programs from high-income countries have performed ≥25 whole liver transplants (52.4% versus 6.2%; P = 0.001) and ≥25 split/reduced liver transplants (53.2% versus 6.2%; P < 0.001) compared to lower-middle-income countries.

CONCLUSIONS

This study represents, to our knowledge, the most geographically comprehensive report on PLT activity and a first step toward global collaboration and data sharing for the greater good of children with liver disease; it is imperative that these centers share the lead in PLT.

Evaluating anti-thymocyte globulin induction doses for better allograft and patient survival in Asian kidney transplant recipients

Anti-thymocyte globulin (ATG) is currently the most widely prescribed induction regimen for preventing acute rejection after solid organ transplantation. However, the optimal dose of ATG induction regimen in Asian kidney recipients is unclear. Using the Korean Organ Transplantation Registry, we performed a retrospective cohort study of 4579 adult patients who received renal transplantation in South Korea and divided them into three groups according to the induction regimen: basiliximab group (n = 3655), low-dose ATG group (≤ 4.5 mg/kg; n = 467), and high-dose ATG group (> 4.5 mg/kg; n = 457). We applied the Toolkit for Weighting and Analysis of Nonequivalent Groups (TWANG) package to generate high-quality propensity score weights for intergroup comparisons. During four-year follow-ups, the high-dose ATG group had the highest biopsy-proven acute rejection rate (basiliximab 20.8% vs. low-dose ATG 22.4% vs. high-dose ATG 25.6%; P < 0.001). However, the rates of overall graft failure (4.0% vs. 5.0% vs. 2.6%; P < 0.001) and mortality (1.7% vs. 2.8% vs. 1.0%; P < 0.001) were the lowest in the high-dose ATG group. Our results show that high-dose ATG induction (> 4.5 mg/kg) was superior to basiliximab and low-dose ATG induction in terms of graft and patient survival in Asian patients undergoing kidney transplant.

Physical Performance Decline During the Early Posttransplantation Period Affects Survival After Living Donor Liver Transplantation

BACKGROUND

Patient physical performance has been emphasized in liver transplant recipients; however, evidence for living donor liver transplantation (LDLT) patients is lacking. This study investigated the impact of physical performance decline during the early posttransplantation period on survival and risk factors for this decline in LDLT recipients.

METHODS

From national registry data, 2703 LDLT patients were divided into 2 groups based on the change in their Karnofsky performance status (KPS) between 1 and 6 mo posttransplantation: declined KPS (n = 188) and control (n = 2515). Multivariable analyses were conducted to control for confounders, including posttransplantation complications.

RESULTS

Estimated 5-y patient survival rates were 91.6% in the declined KPS group and 96.3% in the control group, favoring the latter ( P = 0.003). The survival hazard of KPS decline was significant in a baseline covariates-adjusted Cox model (hazard ratio [HR], 2.60; 95% confidence interval [CI], 1.37-4.95) and an adjusted model accounting for posttransplantation complications (HR, 3.38; 95% CI, 1.70-6.72). In subgroup analyses, KPS decline independently reduced survival in patients without complications (HR, 3.95; 95% CI, 1.67-9.34), and the trend was similar in patients with complications, although significance was marginal (HR, 3.02; 95% CI, 0.98-9.27). We found that only posttransplantation complications, such as rejection, infection, bile duct complication, and vascular complication, were significant risk factors for KPS decline after LDLT.

CONCLUSIONS

Physical performance decline during the early posttransplantation period independently reduced survival rates, and posttransplantation complications were the only significant risk factors for physical performance decline in LDLT recipients.

Keratoplasty Registries: Lessons Learned

ABSTRACT

Clinical registries have been developed for decades in the field of ophthalmology, and they are especially well-suited to the study of keratoplasty practices. A comprehensive donor/recipient registry system can provide insight into donor, recipient, and surgical factors associated with immediate and long-term outcomes and adverse reactions. Furthermore, linkage with demographic databases can elucidate relationships with social determinants of health and potentially shape public policy. The vast sample size and multicenter nature of registries enable researchers to conduct sophisticated multivariate or multilayered analyses. In this review, we aim to emphasize the importance of registry data for keratoplasty practice and 1) summarize the structure of current keratoplasty registries; 2) examine the features and scientific contributions of the registries from Australia, the United Kingdom, Singapore, the Netherlands, Sweden, Eye Bank Association of America, and European Cornea and Cell Transplant registries; 3) compare registry-based studies with large single-site clinical studies; 4) compare registry-based studies with randomized control studies; and 5) make recommendations for future development of keratoplasty registries. Keratoplasty registries have increased our knowledge of corneal transplant practices and their outcomes. Future keratoplasty registry-based studies may be further strengthened by record linkage, data sharing, and international collaboration.

Impact of predicted heart mass-based size matching on survival after heart transplantation in Korea: Analysis of the Korean Organ Transplant Registry

BACKGROUND

Previous studies regarding donor-recipient size and sex matching in heart transplantation (HTx) mainly included Caucasians with only a small portion of Asians. Even predicted heart mass (PHM) has not yet been elucidated in Asians. We evaluated the association between donor-recipient sex and size matching, including mismatching by PHM, and post-heart transplant survival in Korea.

METHODS

We enrolled 660 adult HTx recipients between January 2014 and December 2020 using the Korean Organ Transplant Registry data. Recipients were categorized based on donor-recipient PHM, body weight, and sex matching. The primary outcome was 1-year mortality and retransplantation after HTx and survival analyses were performed using Kaplan-Meier method and Cox proportional hazard models.

RESULTS

Among 660 patients, 74 (11.2%), 404 (61.2%), and 182 (27.6%) received undersized (<-15%), matched (-15% to 20%), and oversized (>20%) hearts by PHM, respectively. Size mismatching by PHM was present in a large number of sex-mismatched patients with 85.1% of male donor-female recipients being classified as oversized by PHM and 62.2% of female donor-male recipients being classified as undersized by PHM. Recipients of undersized or oversized hearts by PHM showed an increased 1-year mortality compared with recipients of matched-size hearts (14.8% versus 9.7%; log-rank p = 0.038). The increased mortality persisted after adjusting for other factors affecting mortality (hazard ratio = 1.60, 95% confidence interval: 1.01-2.56). These associations were not shown in obese recipients (body mass index ≥25 kg/m²). Heart size mismatching by body weight (log-rank p = 0.332) or sex mismatching (all, log-rank p > 0.05) did not predict 1-year mortality after HTx.

CONCLUSION

Heart size matching by PHM, not by body weight or sex, was associated with increased 1-year mortality after HTx in Korea.

Impact of donor hypertension on graft survival and function in living and deceased donor kidney transplantation: a nationwide prospective cohort study

OBJECTIVES

Hypertensive living donors are potential candidates to expand the kidney donor pool. However, the impact of donor hypertension on graft survival and function remains to be clarified.

METHODS

We analyzed 3907 kidney transplant recipients registered in a nationwide prospective cohort from 2014 to 2018. Patients were divided by donor types and the presence of donor hypertension. The primary and secondary outcome was the occurrence of death-censored graft failure and renal allograft function, respectively.

RESULTS

The prevalence of hypertension was 9.4% (258/2740) and 19.9% (232/1167) in living and deceased donors, respectively. During a median follow-up of 21.8 months, death-censored graft survival rate was significantly worse in recipients of hypertensive living donors than in those of normotensive living donors ( P  = 0.008). In multivariable analysis, recipients of hypertensive living donors had a significantly increased risk of graft loss (adjusted hazard ratio 2.91; P  = 0.009). The risk of allograft loss was not different between recipients of hypertensive living and normotensive deceased donors. Propensity score-matched analyses had consistent worse graft survival rate in recipients of hypertensive living donors compared to those of normotensive living donors ( P  = 0.027), while it was not different between recipients of hypertensive living and normotensive deceased donors. Hypertension in living donors had a significant negative impact on one-year graft function (adjusted unstandardized β -3.64; P  = 0.011).

CONCLUSIONS

Hypertensive living donor recipients have significantly higher risks of renal allograft loss than normotensive living donor recipients, and showed similar outcomes compared to recipients of normotensive deceased donors.

Effect of pretransplant dialysis vintage on clinical outcomes in deceased donor kidney transplant

The waiting time for deceased donor kidney transplants (DDKT) is increasing. We evaluated DDKT prognosis according to the pretransplant dialysis vintage. A total of 4117 first-time kidney transplant recipients were enrolled from a prospective nationwide cohort in Korea. DDKT recipients were divided into tertiles according to pretransplant dialysis duration. Graft failure, mortality, and composite were compared between DDKT and living donor kidney transplant (LDKT) recipients. Pretransplant dialysis vintage was longer annually in DDKT recipients. In the subdistribution of the hazard model for the competing risk, the first tertile did not show an increased risk of graft failure compared with LDKT recipients; however, the second and third tertile groups had an increased risk of graft failure compared to LDKT recipients (adjusted hazard ratio [aHR] 3.59; 95% confidence interval [CI] 1.69-7.63; P < 0.001; aHR 2.37; 95% CI 1.06-5.33; P = 0.037). All DDKT groups showed a significantly higher risk of patient death than LDKT, with the highest risk in the third tertile group (aHR 11.12; 95% CI 4.94-25.00; P < 0.001). A longer pretransplant dialysis period was associated with a higher risk of the composite of patient death and graft failure in DDKT recipients. DDKT after a short period of dialysis had non-inferior results on graft survival compared with LDKT.

An ex-ante cost-utility analysis of the deemed consent legislation compared to expressed consent for kidney transplantations in Nova Scotia

Background

This study was an ex-ante cost-utility analysis of deemed consent legislation for deceased organ donation in Nova Scotia, a province in Canada. The legislation became effective in January 2021. The study's objective was to assess the conditions necessary for the legislation change’s cost-effectiveness compared to expressed consent, focusing on kidney transplantation (KT).

Method

We performed a cost-utility analysis using a Markov model with a lifetime horizon. The study was from a Canadian payer perspective. The target population was patients with end-stage kidney disease (ESKD) in Atlantic Canada waitlisted for KT. The intervention was the deemed consent and accompanying health system transformations. Expressed consent (before the change) was the comparator. We simulated the minimum required increase in deceased donor KT per year for the cost-effectiveness of the deemed consent. We also evaluated how changes in dialysis and maintenance immunosuppressant drug costs and living donor KT per year impacted cost-effectiveness in sensitivity analyses.

Results

The expected lifetime cost of an ESKD patient ranged from $177,663 to $553,897. In the deemed consent environment, the expected lifetime cost per patient depended on the percentage increases in the proportion of ESKD patients on the waitlist getting a KT in a year. The incremental cost-utility ratio (ICUR) increased with deceased donor KT per year. Cost-effectiveness of deemed consent compared to expressed consent required a minimum of a 1% increase in deceased donor KT per year. A 1% increase was associated with an ICUR of $32,629 per QALY (95% CI: − $64,279, $232,488) with a 81% probability of being cost-effective if the willingness-to-pay (WTP) was $61,466. Increases in dialysis and post-KT maintenance immunosuppressant drug costs above a threshold impacted value for money. The threshold for immunosuppressant drug costs also depended on the percent increases in deceased donor KT probability and the WTP threshold.

Conclusions

The deemed consent legislation in NS for deceased organ donation and the accompanying health system transformations are cost-effective to the extent that they are anticipated to contribute to more deceased donor KTs than before, and even a small increase in the proportion of waitlist patients receiving a deceased donor KT than before the change represents value for money.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12962-022-00390-z.

The Korean Organ Transplantation Registry (KOTRY): an overview and summary of the kidney-transplant cohort

Background

As the need for a nationwide organ-transplant registry emerged, a prospective registry, the Korean Organ Transplantation Registry (KOTRY), was initiated in 2014. Here, we present baseline characteristics and outcomes of the kidney-transplant cohort for 2014 through 2019.

Methods

The KOTRY consists of five organ-transplant cohorts (kidney, liver, lung, heart, and pancreas). Data and samples were prospectively collected from transplant recipients and donors at baseline and follow-up visits; and epidemiological trends, allograft outcomes, and patient outcomes, such as posttransplant complications, comorbidities, and mortality, were analyzed.

Results

From 2014 to 2019, there were a total of 6,129 registered kidney transplants (64.8% with living donors and 35.2% with deceased donors) with a mean recipient age of 49.4 ± 11.5 years, and 59.7% were male. ABO-incompatible transplants totaled 17.4% of all transplants, and 15.0% of transplants were preemptive. The overall 1- and 5-year patient survival rates were 98.4% and 95.8%, respectively, and the 1- and 5-year graft survival rates were 97.1% and 90.5%, respectively. During a mean follow-up of 3.8 years, biopsy-proven acute rejection episodes occurred in 17.0% of cases. The mean age of donors was 47.3 ± 12.9 years, and 52.6% were male. Among living donors, the largest category of donors was spouses, while, among deceased donors, 31.2% were expanded-criteria donors. The mean serum creatinine concentrations of living donors were 0.78 ± 0.62 mg/dL and 1.09 ± 0.24 mg/dL at baseline and 1 year after kidney transplantation, respectively.

Conclusion

The KOTRY, a systematic Korean transplant cohort, can serve as a valuable epidemiological database of Korean kidney transplants.

Non-Renal Risk Factors for Chronic Kidney Disease in Liver Recipients with Functionally Intact Kidneys at 1 Month

Chronic kidney disease (CKD) is a critical complication of liver transplants, of which non-renal risk factors are not fully understood yet. This study aimed to reveal pre- and post-transplant risk factors for CKD (<60 mL/min/1.73 m2), examining liver recipients with functionally intact kidneys one month after grafting using nationwide cohort data. Baseline risk factors were analyzed with multivariable Cox regression analyses and post-transplant risk factors were investigated with the time-dependent Cox model and matched analyses of time-conditional propensity scores. Of the 2274 recipients with a one-month eGFR ≥ 60 mL/min/1.73 m2, 494 (22.3%) developed CKD during a mean follow-up of 36.6 ± 14.4 months. Age, female sex, lower body mass index, pre-transplant diabetes mellitus, and lower performance status emerged as baseline risk factors for CKD. Time-dependent Cox analyses revealed that recurrent hepatocellular carcinoma (HR = 1.93, 95% CI 1.06−3.53) and infection (HR = 1.44, 95% CI 1.12−1.60) were significant post-transplant risk factors for CKD. Patients who experienced one of those factors showed a significantly higher risk of subsequent CKD compared with the matched controls who lacked these features (p = 0.013 for recurrent hepatocellular carcinoma, and p = 0.003 for infection, respectively). This study clarifies pre- and post-transplant non-renal risk factors, which lead to renal impairment after LT independently from patients’ renal functional reserve.

Comparison of early and late Pneumocystis jirovecii Pneumonia in kidney transplant patients: the Korean Organ Transplantation Registry (KOTRY) Study

Late Pneumocystis jirovecii pneumonia (PJP) is not rare in the era of universal prophylaxis after kidney transplantation. We aimed to determine the nationwide status of PJP prophylaxis in Korea and compare the incidence, risk factors, and outcomes of early and late PJP using data from the Korean Organ Transplantation Registry (KOTRY), a nationwide Korean transplant cohort. We conducted a retrospective analysis using data of 4,839 kidney transplant patients from KOTRY between 2014 and 2018, excluding patients who received multi-organ transplantation or were under 18 years old. Cox regression analysis was performed to determine risk factors for early and late PJP. A total of 50 patients developed PJP. The number of patients who developed PJP was same between onset before 6 months and onsets after 6 months. There were no differences in the rate, duration, or dose of PJP prophylaxis between early and late PJP. Desensitization, higher tacrolimus dose at discharge, and acute rejection were associated with early PJP. In late PJP, old age as well as acute rejection were significant risk factors. In conclusion late PJP is as common and risky as early PJP and requires individualized risk-based prophylaxis, such as prolonged prophylaxis for old patients with a history of rejection.

Renal safety of tenofovir disoproxil fumarate and entecavir in liver transplant patients: a nationwide Korean registry study

BACKGROUND AND AIMS

Tenofovir disoproxil fumarate (TDF) and entecavir (ETV) have been recommended after liver transplantation to prevent recurrence of hepatitis B virus infection. Despite its proven efficacy, the renal safety of TDF has not been established in liver transplant recipients. We aimed to compare the effects of TDF and ETV on renal function in liver transplant recipients and to evaluate risk factors for renal dysfunction after liver transplantation.

METHODS

This is a retrospective, observational multicenter study of data from the Korean Organ Transplantation Registry. We included adults who underwent liver transplantation for hepatitis B virus-related complications from April 2014 to December 2017 and received TDF or ETV post-transplantation. Renal dysfunction was defined as an estimated glomerular filtration rate decline by at least 20% from baseline (1 month post-transplantation). Median duration of follow-up was 29 months (interquartile range 19-42).

RESULTS

A total of 804 liver transplant patients were included. The cumulative probability of renal dysfunction was significantly higher in the TDF group than in the ETV group. Multivariable analysis confirmed that TDF was independently associated with an increased risk of renal dysfunction (hazard ratio = 1.47, 95% confidence interval 1.12-1.92; p = 0.005). Independent risk factors for renal dysfunction included older age, worse baseline renal function, and low body mass index. Overall survival rate was significantly lower in patients with renal dysfunction than in those without.

CONCLUSIONS

In this nationwide study, the use of TDF was associated with an increased risk of renal dysfunction, when compared with ETV.

Dominant predictors of early post-transplant outcomes based on the Korean Organ Transplantation Registry (KOTRY)

Data for Asian kidney transplants are very limited. We investigated the relative importance of prognostic markers in Asian kidney transplants by using Korean Organ Transplantation Registry (KOTRY) cohort. Prediction models were developed by data-driven variable selection approach. The relative importance of the selected predictors was measured by dominance analysis. A total of 4854 kidney transplant donor-recipient pairs were analyzed. Overall patient survival rates were 99.8%, 98.8%, and 91.8% at 1, 3, and 5 years, respectively. Death-censored graft survival rates were 98.4%, 97.0%, and 95.8% at 1, 3, and 5 years. Biopsy-proven acute rejection free survival rates were 90.1%, 87.4%, and 87.03% at 1, 3, and 5 years. The top 3 dominant predictors for recipient mortality within 1 year were recipient cardiovascular disease history, deceased donor, and recipient age. The dominant predictors for death-censored graft loss within 1 year were acute rejection, deceased donor, and desensitization. The dominant predictors to acute rejection within 1 year were donor age, HLA mismatched numbers, and desensitization. We presented clinical characteristics of patients enrolled in KOTRY during the last 5 years and investigated dominant predictors for early post-transplant outcomes, which would be useful for clinical decision-making based on quantitative measures.

Safety of Tacrolimus Monotherapy within 12 Months after Liver Transplantation in the Era of Reduced Tacrolimus and Mycophenolate Mofetil: National Registry Study

Tacrolimus monotherapy is accepted as a feasible option during early post-liver transplantation as per current international consensus guidelines. However, its effects in the recent era of reduced tacrolimus (TAC) and mycophenolate mofetil (MMF) remain unclear. Liver recipients who either received TAC monotherapy from the treatment onset or switched from TAC/MMF to TAC-mono within 12 months (TAC-mono group; n = 991) were chronologically matched to patients who continued to receive TAC/MMF (TAC/MMF group; n = 991) at the corresponding time points on time-conditional propensity scores. Outcomes within 12 months after matched time points were compared. Biopsy-proven rejection (TAC/MMF: 3.5% vs. TAC-mono: 2.6%; p = 0.381) and graft failure (0.2% vs. 0.7%; p = 0.082) were similar in both groups. However, the decline in eGFR was 3.1 mL/min/1.73 m² (95% CI: 0.8–5.3) greater at six months (p = 0.008) and 2.4 mL/min/1.73 m² (95% CI: −0.05–4.9) greater at 12 months (p = 0.048) after the matched time points in TAC-mono group than that in TAC/MMF group. TAC trough levels were also higher in the TAC-mono group throughout the study period. TAC-mono within 12 months after liver transplantation is immunologically safe. However, it can increase the required TAC dose and the decline in renal function than that in TAC/MMF combination therapy.

Personalized Prediction of Kidney Function Decline and Network Analysis of the Risk Factors after Kidney Transplantation Using Nationwide Cohort Data

We developed a machine-learning-based model that could predict a decrease in one-year graft function after kidney transplantation, and investigated the risk factors of the decreased function. A total of 4317 cases were included from the Korean Organ Transplant Registry (2014−2019). An XGBoost model was trained to predict the recipient’s one-year estimated glomerular filtration rate (eGFR) below 45 mL/min/1.73 m2 using 112 pre- and peri-transplantation variables. The network of model factors was drawn using inter-factor partial correlations and the statistical significance of each factor. The model with seven features achieved an area under the curve of 0.82, sensitivity of 0.73, and specificity of 0.79. The model prediction was associated with five-year graft and rejection-free survival. Post-transplantation hospitalization >25 days and eGFR ≥ 88.0 were the prominent risk and preventive factors, respectively. Donor age and post-transplantation eGFR < 59.8 were connected to multiple risk factors on the network. Therefore, careful donor−recipient matching in older donors, and avoiding pre-transplantation risk factors, would reduce the risk of graft dysfunction. The model might improve long-term graft outcomes by supporting early detection of graft dysfunction, and proactive risk factor control.

Risk Due to ABO Incompatibility and Donor-Recipient Weight Mismatch in Living Donor Kidney Transplantation: A National Cohort Study

The effect of donor-recipient weight mismatch is not well established in ABO-incompatible living donor kidney transplantation (LDKT). A total of 2584 LDKT patients in the Korean Organ Transplantation Registry were classified into four groups according to the presence or absence of ABO incompatibility and donor-recipient weight mismatch (donor-to-recipient weight ratio (DRWR) < 0.8). In a multivariable Cox analysis, the combination of ABO incompatibility and DRWR incompatibility (n = 124) was an independent risk factor for graft survival (HR = 2.73, 95% CI = 1.11-6.70) and patient survival (HR = 3.55, 95% CI = 1.39-9.04), whereas neither factor alone was a significant risk factor for either outcome. The combination of ABO incompatibility and DRWR incompatibility was not an independent risk factor for biopsy-proven graft rejection (HR = 1.27, 95% CI = 0.88-1.82); however, it was an independent risk factor for pneumonia (HR = 2.94, 95% CI = 1.64-5.57). The mortality rate due to infection was higher among patients with both ABO incompatibility and DRWR incompatibility than among patients with neither factor or with either factor alone. The combination of ABO incompatibility and DRWR incompatibility was an independent risk factor for graft and patient survival after LDKT, whereas neither factor alone significantly affected graft or patient survival. Thus, donor-recipient weight matching should be cautiously considered in LDKT with ABO incompatibility.

[Organ donations in Algeria: restrictions and perspectives]

Le but de cet article est de mettre en exergue la nécessité et l´obligation d´associer au don d´organes provenant des vivants, celui issu des personnes décédées, une source de greffon dont l´apport est inégalable, un plaidoyer avec un triple objectif: 1) analyser l´apport du don issu des vivants, en termes de chiffre, à travers deux éléments: le degré d´implication de nos compétences médico-chirurgicales et nos dispositions réglementaires qui lui sont relatives. 2) Montrer que, ce don issu des vivants, même optimisé, restera toujours en deçà des besoins de nos malades et il n´apporte qu´une partie de la solution. 3) L´autre partie se trouve dans les services de réanimation, le donneur décédé, une source de don qui ne peut être substituée par celle des vivants et qui concerne nos malades ne disposant d'aucun donneur vivant et surtout ceux en attente d´un organe vital: cœur, poumon, foie, ou un rein pour ceux n'ayant plus la possibilité de faire la dialyse. Des patients condamnés à mourir s´ils ne sont pas transplantés dans les semaines à venir. A cet égard, seuls le professionnalisme et l´entière disponibilité du personnel dédié à cette activité, sont capables de nous débarrasser des préjugés qui accablent, à ce jour, injustement et systématiquement l´implication de notre société vis-à-vis de ce type de don, salvateur. Les pays ayant su promouvoir et se servir de cette source de don, un programme national lui a été priorisé et déployé en réseaux. Un programme aux résultats sûrs, fondé sur des normes universelles d´éthique de recrutement, de formation et organisationnelles. Pour les autorités sanitaires de ces mêmes pays, il est irrationnel et déraisonnable que ces greffons soient partageables avec les malades des autres pays: tant que cette source de don demeure l´unique à permettre la seule modalité thérapeutique salvatrice pour ce type de malades graves et tant que ce type de greffons resteront insuffisants pour satisfaire les besoins de tous leurs patients.

Declining trend of preemptive kidney transplantation and impact of pretransplant dialysis: a Korean nationwide prospective cohort study

We evaluated the temporal trend of preemptive kidney transplantation (KT) and the effect of pretransplant dialysis duration on post-transplant outcomes. This was a nationwide cohort study of the first-time 3392 living donor KT (LDKT) recipients (2014-2019). The annual changes in proportion of preemptive KT, factors associated with preemptive KT, and post-transplant outcomes were analyzed. Preemptive KT was performed in 816 (24.1%) patients. Annual trend analysis revealed gradual decrease in preemptive KT over time (P = 0.042). Among the underlying causes of preemptive KT, the proportion of diabetes increased and that of glomerulonephritis decreased during the study period. Glomerulonephritis as the primary renal disease was a predictor of preemptive KT. Patients with pretransplant dialysis >6 months showed increased graft failure risk than preemptive KT in the subdistribution of hazard model for competing risk (adjusted hazard ratio [aHR], 2.53; 95% confidence interval [CI], 1.09-5.87; P = 0.031) and in propensity score-matched analysis (aHR, 2.45; 95% CI, 1.02-5.92; P = 0.034); however, pretransplant dialysis ≤6 months showed comparable graft survival with preemptive KT in both analyses. Preemptive KT declined over successive years, associated with an increase in diabetes and a decrease in glomerulonephritis as underlying causes of KT. Short period of dialysis less than 6 months does not affect graft survival compared with preemptive KT; however, longer dialysis decreases graft survival.

Synergistic impact of pre-sensitization and delayed graft function on allograft rejection in deceased donor kidney transplantation

The aim of this study is to investigate whether or not delayed graft function (DGF) and pre-transplant sensitization have synergistic adverse effects on allograft outcome after deceased donor kidney transplantation (DDKT) using the Korean Organ Transplantation Registry (KOTRY) database, the nationwide prospective cohort. The study included 1359 cases between May 2014 and June 2019. The cases were divided into 4 subgroups according to pre-sensitization and the development of DGF post-transplant [non-pre-sensitized-DGF(−) (n = 1097), non-pre-sensitized-DGF(+) (n = 127), pre-sensitized-DGF(−) (n = 116), and pre-sensitized-DGF(+) (n = 19)]. We compared the incidence of biopsy-proven allograft rejection (BPAR), time-related change in allograft function, allograft or patient survival, and post-transplant complications across 4 subgroups. The incidence of acute antibody-mediated rejection (ABMR) was significantly higher in the pre-sensitized-DGF(+) subgroup than in other 3 subgroups. In addition, multivariable cox regression analysis demonstrated that pre-sensitization combined with DGF is an independent risk factor for the development of acute ABMR (hazard ratio 4.855, 95% confidence interval 1.499–15.727). Moreover, DGF and pre-sensitization showed significant interaction (p-value for interaction = 0.008). Pre-sensitization combined with DGF did not show significant impact on allograft function, and allograft or patient survival. In conclusion, the combination of pre-sensitization and DGF showed significant synergistic interaction on the development of allograft rejection after DDKT.

Outflow vein venoplasty of left lateral section graft for living donor liver transplantation in infant recipients

The orifice size of the LHV trunk in LLS grafts is often too small for direct anastomosis. Several methods were developed to enlarge the graft and recipient hepatic vein orifices. This study described our surgical techniques to secure hepatic vein reconstruction in infant recipients and analyzed the patency outcomes. Twelve infants undergoing pediatric LDLT were selected during 2-year study period between January 2018 and December 2019. Surgical techniques and vascular complications of graft hepatic vein outflow were analyzed. The mean recipient age was 12.5 ± 4.5 months; mean body weight was 9.4 ± 1.0 Kg; and mean graft-recipient weight ratio was 2.8 ± 0.6%. Primary diseases were biliary atresia in six patients, metabolic diseases in two, hepatoblastoma in two, and acute liver failure in two. Eight LLS grafts were recovered through an open method, and four LLS grafts were recovered through a laparoscopic method. A small superficial LHV branch was present in five of 12 LLS grafts, which was opened to widen the graft hepatic vein orifice. Incision-and-patch venoplasty was performed in 10, unification venoplasty in 1 and no venoplasty in 1. All four LLS grafts recovered through a laparoscopic approach required circumferential vein patch because of very short hepatic vein stump. No patient experienced graft hepatic vein-associated vascular complications during the follow-up period of 19.3 ± 9.3 months. Our surgical techniques with incision-and-patch venoplasty for LLS grafts is beneficial to reduce the risk of hepatic vein outflow obstruction in recipients receiving LLS grafts.

Outcomes after liver transplantation in Korea: Incidence and risk factors from Korean transplantation registry

BACKGROUND/AIMS

To analyze the incidence and risk factors of outcomes after liver transplantation (LT) in the Korean population.

METHODS

This study analyzed data from the liver cohort of Korean Organ Transplantation Registry (KOTRY) who had LT between May 2014 and December 2017. Study measures included the incidence of post-LT outcomes in recipients of living donor LT (LDLT) and deceased donor LT (DDLT). Cox multivariate proportional hazards model was used to determine the potential risk factors predicting the outcomes.

RESULTS

A total of 2,563 adult recipients with LT (LDLT, n=1,956; DDLT, n=607) were included, with mean±standard deviation age of 53.9±8.9 years, and 72.2% were male. The post-LT outcomes observed in each LDLT and DDLT recipients were death (4.0% and 14.7%), graft loss (5.0% and 16.1%), rejection (7.0% and 12.0%), renal failure (2.7% and 13.8%), new onset of diabetes (12.5% and 15.4%), and hepatocellular carcinoma (HCC) recurrence (both 6.7%). In both LDLT and DDLT recipients, the most common post-LT complications were renal dysfunction (33.6% and 51.4%), infection (26.7% and 48.4%), and surgical complication (22.5% and 23.9%). Incidence of these outcomes were generally higher among recipients of DDLT than LDLT. Multivariate analysis indicated recipient age and DDLT as significant risk factors associated with death and graft loss. DDLT and ABO incompatible transplant were prognostic factors for rejection, and HCC beyond Milan criteria at pre-transplant was a strong predictor of HCC recurrence.

CONCLUSION

This study is a good indicator of the post-LT prognosis in the Korean population and suggests a significant burden of post-LT complications.

Impact of preoperative renal replacement therapy on the clinical outcome of heart transplant patients

Renal dysfunction is considered as a relative contraindication for heart transplantation (HTx). However, in the real world setting, many patients with advanced heart failure (HF) experience worsening of renal function and some even require renal replacement therapy (RRT) by the time they undergo HTx. We aimed to investigate the prognosis and clinical outcomes of HTx patients who required RRT during the perioperative period. The Korean Organ Transplant Registry (KOTRY) is a nationwide organ transplant registry in Korea. A total of 501 HTx patients had been prospectively enrolled in the KOTRY registry during 2014–2018. Among the 501 patients, 13 underwent combined heart and kidney transplantation (HKTx). The 488 patients who underwent isolated HTx were grouped according to their pre- and postoperative RRT status. The primary outcome was progression to dialysis-dependent end-stage renal disease (ESRD) after HTx. The secondary outcome was all-cause mortality after HTx. The median follow-up was 22 months (9–39 months). Patients who needed preoperative RRT but were free from postoperative RRT showed comparable overall survival and renal outcome to patients who were free from both pre- and postoperative RRT. In multivariable analysis, preoperative RRT was not associated with progression to ESRD or all-cause mortality after HTx; however, postoperative RRT was a significant predictor for both progression to ESRD and all-cause mortality after HTx. Preoperative creatinine or estimated glomerular filtration rate (eGFR) were not predictive of progression to ESRD after HTx. The present analysis suggests that preoperative RRT requirement does not indicate irreversible renal dysfunction in patients waiting for HTx. However, postoperative RRT was associated with progression to ESRD and mortality after HTx.

Changes in renal function and predictors affecting renal outcome of living kidney donors: a nationwide prospective cohort study

AIM

The safety of donors is an important issue in living donor kidney transplantation. We investigated serial changes in renal function and predictors affecting the renal outcome of living kidney donors.

METHODS

We obtained the data of 456 kidney donors registered to the Korean Organ Transplantation Registry from 2014 to 2016. The estimated glomerular filtration rate (eGFR) changes according to the development of incident chronic kidney disease (CKD) and factors related to CKD were analysed. CKD was defined as an eGFR <60 ml/min/1.73 m² or the presence of proteinuria or albuminuria. The change in eGFR over time was analysed using a linear mixed model.

RESULTS

At 2 years after kidney donation, 21.7% of the donors (99/456) developed CKD. Annual eGFR changes after nephrectomy were 2.2 ml/min/1.73 m² /year in donors without CKD, and - 0.4 ml/min/1.73 m² /year in donors with CKD. Higher systolic blood pressure was associated with higher risk of CKD (odds ratio [OR] 1.322 per 10 mmHg increment, 95% confidence interval [CI] 1.036-1.686, p = .025). Higher pre-donation eGFR (OR 0.906 per 1 ml/min/1.73 m² increment, 95% CI 0.876-0.936, p < .001) and higher ratio of eGFR at discharge to pre-donation (OR 0.603 per 0.1 increment, 95% CI 0.426-0.849, p = .004) were related to lower risk of CKD.

CONCLUSION

Kidney donors without incident CKD at 2 years after donation showed gradual increases in eGFR, whereas donors with CKD had relatively constant eGFR. A low ratio of eGFR at discharge after nephrectomy to baseline was a risk factor of CKD.

Outcomes of ABO-incompatible kidney transplantation in older patients: a national cohort study

BACKGROUND

Outcomes of ABO-incompatible living donor kidney transplantation (ABOi LDKT) in older individuals have not been established.

METHODS

This multicentric observational study, using data from the Korean Organ Transplantation Registry database, included 634 older patients (≥60 years) undergoing kidney transplantation. We compared clinical outcomes of ABOi LDKT (n = 80) with those of ABO-compatible LDKT (ABOc LDKT, n = 222) and deceased donor kidney transplantation (DDKT, n = 332) in older patients.

RESULTS

Death-censored graft survival was similar between the three groups (P = 0.141). Patient survival after ABOi LDKT was similar to that after ABOc LDKT (P = 0.489) but higher than that after DDKT (P = 0.038). In multivariable analysis, ABOi LDKT was not risk factor (hazard ratio [HR] 1.73, 95% confidence interval [CI] 0.29-10.38, P = 0.548), while DDKT was significant risk factor (HR 3.49, 95% CI 1.01-12.23, P = 0.049) for patient survival. Although ABOi LDKT showed higher biopsy-proven acute rejection than ABOc LDKT, the difference was not significant after adjustment with covariates. However, ABOi LDKT was significant risk factor for infection (HR 1.66, 95% CI 1.12-2.45, P = 0.012).

CONCLUSIONS

In older patients, ABOi LDKT was not inferior to ABOc LDKT and was superior to DDKT for patient survival. ABOi LDKT can be recommended for older patients, rather than waiting for DDKT.

Epidemiology, risk factors, and clinical impact of early post-transplant infection in older kidney transplant recipients: the Korean organ transplantation registry study

Background

As in younger recipients, post-transplant infection is a frequent and devastating complication after kidney transplantation (KT) in older recipients. However, few studies have analyzed characteristics of post-transplant infection in older kidney recipients. In this study of a nation-wide cohort of older kidney recipients, we investigated the current epidemiology, risk factors, and clinical impacts of early post-transplant infection, which was defined as infectious complications requiring hospitalization within the first 6 months after KT.

Methods

Three thousand seven hundred thirty-eight kidney recipients registered in the Korean Organ Transplantation Registry between 2014 and 2017 were enrolled. Recipients were divided into two groups, younger (n = 3081) and older (n = 657), with a cutoff age of 60 years. We observed characteristics of early post-transplant infection, and investigated risk factors for the development of infection. We also analyzed the association of early post-transplant infection with clinical outcomes including cardiac events, rejection, graft loss, and all-cause mortality.

Results

The incidence of early post-transplant infection was more frequent in older recipients (16.9% in younger group and 22.7% in older group). Bacteria were the most common causative pathogens of early post-transplant infection, and the most frequent site of infection was the urinary tract in both older and younger recipients. Older recipients experienced more mycobacterial infections, co-infections, and multiple site infections compared with younger recipients. In older recipients, female sex (HR 1.398, 95% CI 1.199–1.631), older donor age (HR 1.010, 95% CI 1.004–1.016), longer hospitalization after KT (HR 1.010, 95% CI 1.006–1.014), and experience of acute rejection (HR 2.907, 95% CI 2.471–3.419) were independent risk factors for the development of early post-transplant infection. Experiencing infection significantly increases the incidence of rejection, graft loss, and all-cause mortality.

Conclusion

Our results illustrate current trends, risk factors, and clinical impacts of early post-transplant infection after KT in older recipients. Considering the poor outcomes associated with early post-transplant infection, careful screening of recipients at high risk for infection and monitoring of recipients who experience infection are advised. In addition, since older recipients exhibit different clinical characteristics than younger recipients, further studies are needed to establish effective strategies for treating older recipients.

Supplementary Information

Supplementary information accompanies this paper at 10.1186/s12877-020-01859-3.

New-onset diabetes after adult liver transplantation in the Korean Organ Transplantation Registry (KOTRY) study

BACKGROUND

New-onset diabetes after transplantation (NODAT) is a serious complication following liver transplantation (LT). The present study aimed to investigate the incidence of and risk factors for NODAT using the Korean Organ Transplantation Registry (KOTRY) database.

METHODS

Patients with history of pediatric transplantation (age ≤18 years), re-transplantation, multi-organ transplantation, or pre-existing diabetes mellitus were excluded. A total of 1,919 non-diabetic adult patients who underwent a primary LT between May 2014 and December 2017 were included. Risk factors were identified using Cox regression analysis.

RESULTS

NODAT occurred in 19.7% (n=377) of adult liver transplant recipients. Multivariate analysis showed steroid use, increased age, and high body mass index (BMI) in recipients, and implantation of a left-side liver graft was closely associated with NODAT in adult LT. In living donor liver transplant (LDLT) patients (n=1,473), open donor hepatectomy in the living donors, steroid use, small for size liver graft (graft to recipient weight ratio ≤0.8), increased age, and high BMI in the recipient were predictive factors for NODAT. The use of antimetabolite and basiliximab induction reduced the incidence of NODAT in adult LT and in adult LDLT.

CONCLUSIONS

Basiliximab induction, early steroid withdrawal, and antimetabolite therapy may prevent NODAT after adult LT. High BMI or advanced age in liver recipients, open donor hepatectomy in living donors, and small size liver graft can predict the occurrence of NODAT after adult LT or LDLT.

A Systematic Review of Opt-out Versus Opt-in Consent on Deceased Organ Donation and Transplantation (2006-2016)

BACKGROUND

Significant numbers of patients in the USA and UK die while waiting for solid organ transplant. Only 1-2% of deaths are eligible as donors with a fraction of the deceased donating organs. The form of consent to donation may affect the organs available. Forms of consent include: opt-in, mandated choice, opt-out, and organ conscription. Opt-in and opt-out are commonly practiced. A systematic review was conducted to determine the effect of opt-in versus opt-out consent on the deceased donation rate (DDR) and deceased transplantation rate (DTR).

METHODS

Literature searches of PubMed and EMBASE between 2006 and 2016 were performed. Research studies were selected based on certain inclusion criteria which include USA, UK, and Spain; compare opt-in versus opt-out; primary data analysis; and reported DDR or DTR. Modeled effect on US transplant activity was conducted using public data from Organ Procurement and Transplantation Network and Centers for Disease Control WONDER from 2006 to 2015.

RESULTS

A total of 2400 studies were screened and six studies were included. Four studies reported opt-out consent increases DDR by 21-76% over 5-14 years. These studies compared 13-25 opt-out countries versus 9-23 opt-in countries. Three studies reported opt-out consent increases DTR by 38-83% over 11-13 years. These studies compared 22-25 opt-out versus 22-28 opt-in countries. Modeled opt-out activity on the USA resulted in 4753-17,201 additional transplants annually.

CONCLUSION

Opt-out consent increases DDR and DTR and may be useful in decreasing deaths on the waiting list in the USA and other countries.

REGISTRATION NUMBER

PROSPERO CRD42019098759.

Development of the Asian Transplant Registry Under the Asian Society of Transplantation

INTRODUCTION

In the Asian region, no international organ transplantation registry exists. Individual centers maintain their own database, or some countries developed a national registration system. To promote collaboration among Asian transplantation societies, the Asian Society of Transplantation (AST) has developed an international transplantation registry for the Asian countries that has been named as the Asian Society Transplant Registry (ASTREG).

METHODS

In 2017, the AST council formed a registry committee to develop 2 kinds of databases: ASTREG-N (nationwide level), which collects yearly aggregated data of participating countries, and ASTREG-H (hospital level), which collects the data of transplant recipients and donors from individual centers.

RESULTS

ASTREG-N collects each country's aggregate data of solid-organ transplantation, such as the total number of transplantations and deceased donors. ASTREG-H collects 5 transplant domains, namely recipient baseline characteristics, immunosuppression, post-transplant event, annual post-transplant evaluation, and donor traits. For the ASTREG-H project, South Korea, Philippines, Mongolia, and Myanmar are the current participants. A web-based secure data entry platform with real-time data visualization and automated data verification systems is currently available. Any participating centers can run this platform as their own data collection system.

CONCLUSION

The ASTREG is a collaborative project that will be the representative solid-organ transplantation database in the Asian region. It can aid in the harmonization of transplantation data in the Asian region.

Effect of simultaneous presence of anti-blood group A/B and -HLA antibodies on clinical outcomes in kidney transplantation across positive crossmatch: a nationwide cohort study

ABO-incompatible (ABOi) and positive crossmatch (XM) kidney transplantation (KT) have been considered immunologically challenging. The present study analyzed the clinical outcomes in XM positive KT based on ABO incompatibility. We used data from the Korea Organ Transplantation Registry, a nationwide database, and a single-center registry. A total of 263 patients with positive XM were divided into an ABO compatible (ABOc) & XM positive (ABOc/XM+, n = 176) group and an ABOi & XM positive (ABOi/XM+, n = 87) group. The overall rejection rate one year after KT was significantly higher in the ABOi/XM+ group than in the ABOc/XM+ group (P < 0.01). A total of four mortalities occurred, all in the ABOi/XM+ patients (P < 0.01). There were no differences in surgical complications or the occurrence of infection-related complications, including BK virus nephropathy. Multivariate analysis indicated that female vs. male (odds ratio (OR), 2.27; P = 0.03), DSA class I (MFI/1000) (OR, 1.10; P = 0.03), DSA class II (MFI/1000) (OR, 1.10; P < 0.01), and ABOi & XM+ status (OR, 2.38; P < 0.01) were significant risk factors for acute rejection during the year after transplantation. Overall graft survival was inferior in ABOi/XM+ patients than in ABOc/XM+ patients (P = 0.02). ABO incompatibility in XM-positive KT patients was found to be a significant risk factor for the development of rejection within one year after transplantation as well as for long-term graft survival. The anti-blood group A, B and anti-HLA antibodies may show synergistic activity.