Donor-recipient gender and size mismatch affects graft success after kidney transplantation

Donor and recipient risk factors for the development of primary graft dysfunction following lung transplantation

Primary Graft Dysfunction (PGD) is a major cause of both short-term and long-term morbidity and mortality following lung transplantation. Various donor, recipient, and technical risk factors have been previously identified as being associated with the development of PGD. Here, we present a comprehensive review of the current literature as it pertains to PGD following lung transplantation, as well as discussing current strategies to mitigate PGD and future directions. We will pay special attention to recent advances in lung transplantation such as ex-vivo lung perfusion, thoracoabdominal normothermic regional perfusion, and up-to-date literature published in the interim since the 2016 ISHLT consensus statement on PGD and the COVID-19 pandemic.

Multiview Clustering to Identify Novel Kidney Donor Phenotypes for Assessing Graft Survival in Older Transplant Recipients

Key Points

An unsupervised machine learning clustering algorithm identified distinct deceased kidney donor phenotypes among older recipients. Recipients of certain donor phenotypes were at a relatively higher risk of all-cause graft loss even after accounting for recipient factors. The use of unsupervised clustering to support kidney allocation systems may be an important area for future study.

Background

Older transplant recipients are at a relatively increased risk of graft failure after transplantation, and some of this risk may relate to donor characteristics. Unsupervised clustering using machine learning may be a novel approach to identify donor phenotypes that may then be used to evaluate outcomes for older recipients. Using a cohort of older recipients, the purpose of this study was to (1 ) use unsupervised clustering to identify donor phenotypes and (2 ) determine the risk of death/graft failure for recipients of each donor phenotype.

Methods

We analyzed a nationally representative cohort of kidney transplant recipients aged 65 years or older captured using the Scientific Registry of Transplant Recipients between 2000 and 2017. Unsupervised clustering was used to generate phenotypes using donor characteristics inclusive of variables in the kidney donor risk index (KDRI). Cluster assignment was internally validated. Outcomes included all-cause graft failure (including mortality) and delayed graft function. Differences in the distribution of KDRI scores were also compared across the clusters. All-cause graft failure was compared for recipients of donor kidneys from each cluster using a multivariable Cox survival analysis.

Results

Overall, 23,558 donors were separated into five clusters. The area under the curve for internal validation of cluster assignment was 0.89. Recipients of donor kidneys from two clusters were found to be at high risk of all-cause graft failure relative to the lowest risk cluster (adjusted hazards ratio, 1.86; 95% confidence interval, 1.69 to 2.05 and 1.73; 95% confidence interval, 1.61 to 1.87). Only one of these high-risk clusters had high proportions of donors with established risk factors (i.e. , hypertension, diabetes). KDRI scores were similar for the highest and lowest risk clusters (1.40 [1.18–1.67] and 1.37 [1.15–1.65], respectively).

Conclusions

Unsupervised clustering can identify novel donor phenotypes comprising established donor characteristics that, in turn, may be associated with different risks of graft loss for older transplant recipients.

Novel Histopathologic and Ultrastructural Findings in Renal Allografts From Patients With Size and Age Mismatches: A Case Series

While reports on the long-term pathology in mismatched allografts have been focused on the donor and recipient body surface area, evidence is emerging to support donor-recipient age difference as an additional prognostic factor. Most reports are based on pediatric recipients receiving older/bigger allografts. Here, we describe three cases with age mismatch including two cases of adult patients receiving pediatric allografts and a third case of a younger patient receiving an allograft from an older donor exhibiting findings not described in extant literature. Each of these cases exhibits unique changes seen in mismatched donor-recipient size/age post-transplant pathology. These non-rejection changes should be suspected in cases of donor-recipient size/age mismatch. In cases of allograft function decline, a full biopsy workup, including electron microscopy, should be considered.

Prediction of early graft function after living donor kidney transplantation by quantifying the "nephron mass" using CT-volumetric software

Early renal function after living-donor kidney transplantation (LDKT) depends on the "nephron mass" in the renal graft. In this study, as a possible donor-recipient size mismatch parameter that directly reflects the "nephron mass," the cortex to recipient weight ratio (CRWR) was calculated by CT-volumetric software, and its ability to predict early graft function was examined. One hundred patients who underwent LDKT were enrolled. Patients were classified into a developmental cohort (n = 79) and a validation cohort (n = 21). Using the developmental cohort, the correlation coefficients between size mismatch parameters, including CRWR, and the posttransplantation estimated glomerular filtration rate (eGFR) were calculated. Multiple regression analysis was conducted to define a formula to predict eGFR 1-month posttransplantation. Using the validation cohort, the validity of the formula was examined. The correlation coefficient was the highest for CRWR (1-month r = 0.66, p < 0.001). By multiple regression analysis, eGFR at 1-month was predicted using the linear model: 0.23 × donor preoperative eGFR + 17.03 × CRWR + 8.96 × preemptive transplantation + 5.10 (adjusted coefficient of determination = 0.54). In most patients in the validation cohort, the observed eGFR was within a 10 ml/min/1.73 m2 margin of the predicted eGFR. CRWR was the strongest parameter to predict early graft function. Predicting renal function using this formula could be useful in clinical application to select proper donors and to avoid unnecessary postoperative medical interventions.

Combined Donor-Recipient Obesity and the Risk of Graft Loss After Kidney Transplantation

Background: As the prevalence of obesity increases globally, appreciating the effect of donor and recipient (DR) obesity on graft outcomes is of increasing importance.

Methods: In a cohort of adult, kidney transplant recipients (2000–2017) identified using the SRTR, we used Cox proportional hazards models to examine the association between DR obesity pairing (body mass index (BMI) &gt;30 kg/m2), and death-censored graft loss (DCGL) or all-cause graft loss, and logistic regression to examine risk of delayed graft function (DGF) and ≤30 days graft loss. We also explored the association of DR weight mismatch (&gt;30 kg, 10-30 kg (D&gt;R; D&lt;R) and &lt;10 kg (D = R)) with each outcome, stratifying by DR obesity pairing.

Results: Relative to non-obese DR, obese DR were highest risk for all outcomes (DCGL: HR 1.26, 95% CI 1.22–1.32; all-cause graft loss: HR 1.09, 95% CI 1.06–1.12; DGF: OR 1.98, 95% CI 1.89–2.08; early graft loss: OR 1.34, 95% CI 1.19–1.51). Donor obesity modified the risk of recipient obesity and DCGL [p = 0.001] and all-cause graft loss [p &lt; 0.001] but not DGF or early graft loss. The known association of DR weight mismatch with DCGL was attenuated when either the donor or recipient was obese.

Conclusion: DR obesity status impacts early and late post-transplant outcomes.

The Role of Donor Sex in Females Undergoing Repeat Kidney Transplant: Does Prior Donor Sex Matter?

Female recipients of male donor kidneys are at increased risk for graft failure because of the HY antigen effect. However, whether prior transplant with a male donor impacts subsequent transplant outcomes is unknown. Therefore, the purpose of this study was to determine whether prior male-current male donor sex is associated with an increased risk of graft failure in female recipients.

Methods

We performed a cohort study of adult female recipients undergoing a second kidney transplant (2000-2017), identified using the Scientific Registry of Transplant Recipients. Using multivariable Cox models, we analyzed the risk of death-censored graft loss (DCGL) if the second transplant was from a male versus female kidney donor, conditional on donor sex at the time of the first transplant. In a secondary analysis, we stratified results by recipient age (>50 or ≤50 y) at the time of retransplant.

Results

Of 5594 repeat kidney transplants, 1397 (25.0%) developed DCGL. Overall, there was no association between first and second donor sex pairing and DCGL. A prior and current female donor (FD₁FD₂) posed a higher risk for DCGL in recipients aged >50 y at second transplant (hazard ratio,≤0.67, confidence interval 0.46-0.98, for all other donor combinations), but posed a lower risk if aged ≤50 y at retransplant (hazard ratio, ≥1.37, confidence interval 1.04-1.80, for all other donor combinations).

Conclusions

Overall, past-current donor sex pairing was not associated with DCGL in female recipients undergoing second kidney transplant; however, the risk with a past and current female donor was increased in older, and decreased in younger, female recipients at retransplant.

Barriers to the donation of living kidneys for kidney transplantation

Since the waiting time for deceased donor kidney transplantation continues to increase, living donor kidney transplantation is an important treatment for end stage kidney disease patients. Barriers to living kidney donation have been rarely investigated despite a growing interest in the utilization of living donor transplantation and the satisfaction of donor safety. Here, we retrospectively analyzed 1658 potential donors and 1273 potential recipients who visited the Seoul National University Hospital for living kidney transplantation between 2010 and 2017 to study the causes of donation discontinuation. Among 1658 potential donors, 902 (54.4%) failed to donate kidneys. The average number of potential donors that received work-up was 1.30 ± 0.66 per recipient. Among living donor kidney transplant patients, 75.1% received kidneys after work-up of the first donor and 24.9% needed work-up of two or more donors. Donor-related factors (49.2%) were the most common causes of donation discontinuation, followed by immunologic or size mismatches between donors and recipients (25.4%) and recipient-related factors (16.2%). Interestingly, withdrawal of donation consent along with refusal by recipients or family were the commonest causes, suggesting the importance of non-biomedical aspects. The elucidation of the barriers to living kidney donation could ensure more efficient and safer living kidney donation.

Race, Education, and Gender Disparities in Transplantation of Kidneys From Hepatitis C Viremic Donors

BACKGROUND

Transplantation of kidneys from hepatitis C virus (HCV)-viremic donors into HCV-negative patients followed by direct-acting antiviral therapy was an important breakthrough to increase the number of life-saving kidney transplants. Data suggest that these transplants offer several benefits; however, it is unknown whether adoption of this practice has been shared equitably, especially among disadvantaged groups.

METHODS

We evaluated United Network for Organ Sharing data on HCV-seronegative adult deceased-donor kidney transplant recipients from January 1, 2017, to June 12, 2020. We compared recipients of a kidney from an HCV antibody- (Ab-)/nucleic acid test- (NAT-), HCV Ab+/NAT-, and HCV NAT+ donor. The primary covariates were as follows: (1) race/ethnicity; (2) female sex; and (3) highest level of education. Models included variables associated with being offered an HCV NAT+ kidney. We fit mixed-effects multinomial logistic regression models with the center as a random effect to account for patient clustering.

RESULTS

Of 48 255 adult kidney-alone deceased-donor kidney transplant HCV-seronegative recipients, 1641 (3.4%) donors were HCV NAT+-, increasing from 0.3% (January 2017-June 2017) to 6.9% (January 2020-June 2020). In multivariable models, racial/ethnic minorities, women, and those with less education were significantly less likely to receive a kidney from an HCV NAT+ donor relative to an HCV Ab-/NAT- and HCV Ab+/NAT- donor. The disparities were most pronounced among Hispanic and Asian patients with less educational attainment (grade school, high school, or some college/tech school).

CONCLUSIONS

Despite an increase in transplants from HCV NAT+ donors, we found substantial racial/ethnic disparities in transplantation of these kidneys. These data highlight how the benefits of a scientific breakthrough are often made less available to disadvantaged patients.

Donor-Recipient Matching in Kidney Transplant: We're Not There Yet

BACKGROUND

Strategic organ allocation is expected to prolong patient and graft survival after transplant. This study explored differences in graft survival when kidneys are allocated based on strategic donor-recipient (D-R) pairing vs with the existing Kidney Allocation System (KAS).

METHODS

Using the Scientific Registry of Transplant Recipients from 2000 to 2014, we used a multivariable Cox model to assess the hazard ratios (HRs) for death or graft failure among 3 hypothetical donor kidneys transplanted into 3 hypothetical recipients, relative to an ideally matched D-R pair. Median predicted survival for each of the 9 possible D-R pairing combinations was determined, and outcomes for strategic D-R pairing were compared with those obtained using the KAS for allocation.

RESULTS

A total of 31,607 patients (29.7%) died or developed graft loss over the study period. Strategic allocation of kidneys resulted in HRs for graft loss of 1.74 (95% confidence interval [CI], 1.41-2.14), 1.82 (95% CI, 1.46-2.26), and 1.74 (95% CI 1.38-2.19) for recipients 1, 2 and 3 respectively, whereas by following the KAS, HRs were 1.93 (95%, CI 1.63-2.28), 2.06 (95% CI, 1.74-2.44), and 1.93 (95% CI, 1.58-2.37); corresponding to 3.84, 11.39, and 7.40 months longer predicted patient or graft survival for recipients 1, 2 and 3 with strategic D-R pairing compared with the KAS.

CONCLUSIONS

Allocation of kidneys by strategic D-R pairing may improve graft survival relative to allocation using the KAS.

The differential impact of size mismatch in live versus deceased donor kidney transplant

BACKGROUND

The impact of weight mismatch between donors and recipients (D-R) undergoing living-donor kidney transplant (LDKT) versus weight-matched deceased donor kidney transplant (DDKT) is not established.

AIM

To determine whether absolute weight mismatch between D-R affects graft survival following LDKT and how this relates to graft outcomes with DDKT when D-R are weight matched.

MATERIALS & METHODS

We used multivariable Cox proportional hazards models and the Scientific Registry of Transplant Recipients to determine the association of weight-mismatched D-R (>50 kg, 30-50 kg or 10-30 kg ((D < R); (D > R) and <10 kg (D = R)) with death-censored graft failure in US LDKT recipients from 2006 to 2017. We also explored outcomes relative to weight-matched DDKT and finally, the impact of combined D-R weight-sex mismatch.

RESULTS

In LDKT, the risk of graft loss was highest in the setting of D < R (HR 1.28, 95% CI 1.05-1.56 for >50 kg difference relative to D = R); however, this was still lower risk than weight-matched DDKT. D-R sex and combined weight-sex mismatch were only important for male recipients (HR 1.47, 95% CI 1.27-1.71 for a male recipient >30 kg larger than their female donor, relative to weight-matched male donor-male recipient). This remained superior to weight-sex-matched DDKT however.

CONCLUSION

D-R weight-sex mismatch is important in LDKT; however, graft survival remains superior to proceeding with matched DDKT. Optimizing D-R matching in LDKT could be facilitated through a national kidney-paired donation registry. LDKT weight-sex mismatch should not be deferred in favor of DDKT.

Risk factors for delayed graft function and their impact on graft outcomes in live donor kidney transplantation

BACKGROUND

Delayed graft function (DGF) is a manifestation of acute kidney injury uniquely framed within the transplant process and a predictor of poor long-term graft function1. It is less common in the setting of living donor (LD) kidney transplantation. However, the detrimental impact of DGF on graft survival is more pronounced in LD2.

PURPOSE

To study the effects of DGF in the setting of LD kidney transplantation.

METHODS

We performed a retrospective analysis of LD kidney transplantations performed between 2010 and 2018 in the UNOS/OPTN database for DGF and its effect on graft survival.

RESULTS

A total of 42,736 LD recipients were identified, of whom 1115 (2.6%) developed DGF. Recipient dialysis status, male gender, diabetes, end-stage renal disease, donor age, right donor nephrectomy, panel reactive antibodies, HLA mismatch, and cold ischemia time were independent predictors of DGF. Three-year graft survival in patients with and without DGF was 89% and 95%, respectively. DGF was the greatest predictor of graft failure at three years (hazard ratio = 1.766, 95% CI: 1.514-2.059, P = 0.001) and was associated with higher rates of rejection (9% vs. 6.28%, P = 0.0003). Among patients with DGF, the graft survival rates with and without rejection were not different.

CONCLUSION

DGF is a major determinant of poor graft functional outcomes, independent of rejection.

Analysis of Factors Influencing Kidney Function of Recipients After Renal Transplantation in Southwestern China: A Retrospective Study

Background: Factors influencing the kidney function of patients after renal transplantation include both recipient-related factors and donor-related factors. To gain a better understanding of these factors and to improve clinical decision-making, we performed a retrospective study of southwestern Chinese people receiving kidney transplantation.

Methods: In this retrospective analysis, a total of 2,462 recipients receiving allogeneic kidney transplantation in West China Hospital of Sichuan University from December 13, 2008 to January 10, 2018 were included. Data on recipient and donor characteristics were extracted from the Transplant Center Database and stratified by discrete time points after kidney transplantation. Univariate and multivariate logistic regression analyses were carried out on the study variables, and kidney function of postoperative patients was monitored using cystatin C (CysC) as the outcome indicator.

Results: From the univariate analysis, several factors showed statistically significant short-term impact on kidney function based on CysC after kidney transplantation, including age, ethnicity, body mass index (BMI), and HLA A-B-DR-DQ loci mismatch. Gender of recipients and gender-consistency between donors and recipients revealed both short-term and long-term influence. Younger donors had significantly better medium-and-long-term influence on kidney function. From the multivariate logistic regression analysis, recipient gender, ethnicity, BMI, and donor age were independent factors affecting postoperative CysC recovery at discrete time points.

Conclusion: Several factors of recipients related to renal function after kidney transplantation, such as gender, ethnicity, BMI and donor's age should be paid more attention to. Moreover, female and non-Han recipients decreased the risk of poor outcome during postoperative kidney function recovery while large BMI of recipients and higher donor age increased the risk. It is useful to predict the postoperative renal function earlier according to corresponding factors, and improve the patient's quality of life.

Donor-recipient Sex Differences Do Not Affect Survival Outcomes After Kidney Transplantation: A Population Cohort Study

BACKGROUND

Donor factors can influence decision making for organ utilization for potential kidney transplant candidates. Prior studies exploring the effect of donor-recipient sex matching on kidney transplant outcomes have reported heterogenous and conflicting results. The aim of this contemporary population-cohort analysis was to explore the effect of donor-recipient sex matching on kidney transplant outcomes in the United Kingdom.

METHODS

In this retrospective, observational study, we analyzed all patients receiving kidney-alone transplants between 2003 and 2018 using UK Transplant Registry data. Stratified by recipient sex, outcomes were compared between male and female donors with univariable/multivariable analyses.

RESULTS

Data were analyzed for 25 140 recipients. Of these, 13 414 (53.4%) of kidneys were from male donors and 15 690 (62.4%) of recipients were male. The odds of initial graft dysfunction (delayed graft function/primary nonfunction) were significantly lower for female donor kidneys transplanted into both male (adjusted odds ratio = 0.89, 95% confidence interval [CI] = 0.80-0.98, P = 0.019) and female (adjusted odds ratio = 0.81, 95% CI = 0.71-0.93, P = 0.003) recipients. Male recipients of female donor kidneys had creatinine levels at 1 year that were 6.3% higher (95% CI = 4.8%-7.7%, P < 0.001) than male recipients of male donor kidneys, with a similar sex difference of 4.1% (95% CI = 2.1%-6.1%, P < 0.001) observed within female recipients. However, neither patient nor graft survival was found to differ significantly by donor sex on either univariable or multivariable analysis.

CONCLUSIONS

Our data provide contemporary data on sex mismatch for recipient counseling and reassurance with regards to equivalent long-term clinical outcomes based upon donor sex.

Kidney Transplantation and "Sex Mismatch": A 10-Year Single-Center Analysis

Background

The effect of a relative disproportion in the size of a transplanted kidney (KT) on graft function and survival is well documented. However, the importance of the H-Y antigen (male donor and female recipient) has not been unambiguously confirmed.

Material/Methods

Our retrospective analysis consists of 230 deceased donor/recipient pairs. The aim of the study was to determine the effect of sex mismatch between donors and recipients on the function of the graft and the graft and patient survival.

Results

In the group of male donors, a statistically significantly lower value of the eGFR (estimated glomerular filtration rate) was recorded for female recipients in the fifth year after the KT (=0.0047). The male donor/female recipient group was an independent risk factor for: eGFR (<60 ml/min (CKD-EPI, Chronic Kidney Disease Epidemiology Collaboration) in the third year after KT [HR 0.1618; (P=0.0004)], acute rejection in the first year after KT [HR 1.8992; (P=0.0387)], and the 5-year graft survival was significantly worse in this group. By adjusting the results for age and induction, this group was at significantly higher risk for decreased graft function (eGFR <30 ml/min) if the age of the donor was ≤50 years old and the recipient was >45 years old in the fifth year [HR 11.1676; (P=0.0139)], the age of the donor was ≤50 years old/recipient was ≤45 years old in the third year [HR 1.2500; (P=0.0050)], and also in the fifth year after KT [HR 8.1993; (P=0.0183)].

Conclusions

Based on our analysis, the differences in the incidence of acute rejection episodes as well as in graft survival among the different groups of patients were confirmed. The group with the highest risk, in cases of an acute rejection episode, is a male donor/female recipient.

Improving HLA matching in living donor kidney transplantation using kidney paired exchange program

BACKGROUND

The inclusion of compatible pairs within kidney paired exchange programs has been described as a way to enhance these programs. Improved immunological matching for the recipient in compatible pair has been described to be a possible benefit.

METHODS

The main purpose of our study was to determine if the introduction of compatible pairs in the Portuguese kidney paired exchange program would result in a better match for these patients, but also to assess if this strategy would increase the number of incompatible pairs with a possible match. We included 17 compatible pairs in kidney paired exchange pool of 35 pairs and performed an in-silico simulation determining HLA eplet mismatch load between the co-registered and matched pairs using HLA MatchMaker, version 3.0.

RESULTS

Our study showed that the inclusion of fully HLA-A, -B, -DR mismatched compatible pairs within the national Portuguese KEP increased matched rate within ICP (0.71%) and improved HLA eplet matching within compatible pairs. 16 of 17 (94.12%) of the CP obtained one or more transplants possibilities and 13 (81.25%) would have been transplanted with significantly lower HLA class I and class II total and antibody-verified eplet mismatch load (83.9 ± 16.9 vs. 59.8 ± 12.2, P = .002 and 30.1 ± 5.5 vs. 21.2 ± 3.0, P = .003, respectively).

CONCLUSIONS

This strategy is a viable alternative for compatible pairs seeking a better matched kidney and Portuguese KEP program should allow them this possibility.

Impact of Kidney Donor Profile Index Scores on Post-Transplant Clinical Outcomes Between Elderly and Young Recipients, A Multicenter Cohort Study

We investigated if clinical outcomes after kidney transplantation (KT) from deceased donors (DDs) with high Kidney Donor Profile Index (KDPI) can be different according to the age of KT recipients (KTRs). Six-hundred fifty-seven KTRs from 526 DDs were included from four transplant centers. We divided KTRs into elderly-KTR and young-KTR groups based on age 60 and each group was subdivided into high- or low-KDPI subgroup based on KDPI score of 65%. We compared short-term and long-term clinical outcomes among those four subgroups (low KDPI-young KTR, low KDPI-elderly-KTR, high KDPI-young-KTR, high KDPI-elderly-KTR). In short-term outcomes including acute rejection, BK virus and CMV infection, there was no significant difference among the four subgroups. In the long-term outcomes, the development of cardiovascular disease was higher in the high KDPI-elderly-KTR group than the other groups. In comparison of allograft survival rate, the high KDPI-young KTR subgroup showed highest risk for allograft failure and there was significant interaction between high-KDPI donors and young-KTR on allograft survival rate (P = 0.002). However, there was no significant difference in comparison of the patient survival rate. In conclusion, clinical impact of high-KDPI in DDs on post-transplant allograft survival may be less significant in elderly-KTR than in young-KTR.

The impact of gender matching between donor and recipient on the outcome of kidney transplant patients: A retrospective study

The influence of donor and recipient gender on patients postkidney transplant (KT) is still controversial, and literature data do not present unanimous conclusions. We were concerned with the gender impact on the outcome of kidney transplantation at the level of acute rejection (AR), graft function represented by serum creatinine level, delayed graft function (DGF), graft survival, and infection rate. The impact of gender matching between donors and recipients was studied in 299 KT recipients performed in the Transplantation Unit, Middle East Institute of Health, Bsalim, Lebanon, between November 1998 and September 2014. The patients were divided into the following groups: Group I (131 patients, male donor to male recipient), Group II (55 patients, male donor to female recipient), Group III (88 patients, female donor to male recipient), and Group IV (25 patients, female donor to female recipient). AR and DGF were not statistically different among the four groups. Moreover, all groups showed excellent graft survival with no statistical difference. Interestingly, human leukocyte antigen AB-DR matching (P < 0.001) and sensitization were statistically different among the four groups (P = 0.05). The number of patients with infections was statistically significantly lower in Group I (35.4%) and Group III (37.5%) (P = 0.35). Most importantly, graft function, represented by serum creatinine, showed a statistically significant difference among the four groups (P <0.004), with Group II (male to female) and Group IV (female to female) showing the best improvement in five-year survival. However, Group III (female to male) had the worst posttransplant graft function. These results revealed that gender impacts graft function, and Group II, male donor to female recipient, had the best 5-year graft function. This emphasizes that gender should be regarded as a determinant for the success of kidney transplantation.

Impact of adjusted kidney volume measured in the bench surgery on one-year renal function in kidney transplantation

BACKGROUND

Kidney transplantation is the treatment of choice in patient with end stage chronic kidney disease, offering the best long term survival and greater Quality of Life in this group of patients. Graft volume was correlated with improved renal function in living donor transplantations. The primary aim of this study was to correlate renal volume adjusted to body surface area with renal function one year (estimated glomerular filtration rate; eGFR) after kidney transplantation.

METHODS

This single-center, prospective cohort study included 256 patients who underwent kidney transplantation from January 2011 through December 2015 at Hospital das Clínicas de Botucatu-UNESP. We evaluated three kidney measurements during the bench surgery; the final graft volume was calculated using the ellipsoid formula and adjusted to body surface area.

RESULTS

In the living donors there was positive correlation between adjusted graft volume and eGFR (r = 0.311, p = 0.008). Multivariate analysis revealed that low rejection rate and increased adjusted graft volume were independent factors correlated with eGFR. In deceased donors, there was no correlation between adjusted kidney volume and eGFR (r = 0.08, p = 0.279) in univariate analysis, but a multivariate analysis indicated that lower kidney donor profile index (KDPI), absence of rejection and high adjusted kidney volume were independent factors for better eGFR.

CONCLUSION

Adjusted kidney volume was positively correlated with a satisfactory eGFR at one year after living donor and deceased donor transplantations.

Effect of recipient-donor sex and weight mismatch on graft survival after deceased donor renal transplantation

This study evaluated the combined effect of recipient-to-donor weight and sex mismatch after deceased-donor renal transplantation in a German transplant cohort and the evolution of recipient-to-donor weight difference over a 13-year observation period. The association of absolute weight and sex difference with graft failure was explored in an outpatient cohort of deceased-donor transplant recipients who underwent kidney transplantation between 2000 and 2012. Graft failure was defined as repeated need for dialysis or death with a functioning graft. Recipient and donor sex pairings were classified as sex concordant (MDMR/FDFR) or discordant (MDFR/FDMR). These classes were further stratified into four groups according to recipient-to-donor weight mismatch ≥10 kg (recipient > donor) or <10 kg (recipient < donor). Multivariable Cox proportional hazards models were applied to evaluate the time to graft loss adjusting for donor, immunologic, surgical, organizational, and recipient predictors. Sex-concordant transplant pairings <10 kg weight difference served as the reference group. Among 826 transplant recipients, 154 developed graft failure (18.6%). Median graft survival time was 3.9 years; first quartile (0.2–1.2), second quartile (1.2–2.9), third quartile (2.9–5.8), and fourth quartile (5.8–12.4). After multivariable adjustment, the highest relative hazard for graft failure was observed for sex-discordant transplant pairings with a ≥10 kg weight difference between recipient and donor (compared to the reference group MDMR/FDFR with weight difference <10 kg, MDMR/FDFR with weight difference ≥10 kg, hazard ratio 1.86, 95% confidence interval 1.07–3.32—p = 0.029; MDFR/FDMR with weight difference <10 kg, hazard ratio 1.14, 95% confidence interval 0.78–1.68—p = 0.507, and MDFR/FDMR with weight difference ≥10 kg, hazard ratio 2.00, 95% confidence interval 1.15–3.48—p = 0.014). A recipient-to-donor weight mismatch of ≥10 kg was associated with an increased risk of graft loss or recipient death with a functioning graft. Concurrent sex discordance seemed to enhance this effect as indicated by an increase in the hazard ratio. We detected no significant tendency for increasing recipient-to-donor weight differences from 2000 to 2012.

Gender Differences in Kidney Transplantation – 10-Year Retrospective Study

Background: Chronic kidney disease represents a world-wide health problem affecting approximately 195 million women around the world. Risk of development of chronic kidney disease is greater in women; therefore, the World Kidney Day 2018 was dedicated to kidney disease, treatment options, and its specifics in female patients.

Materials and Methods: We retrospectively analysed a cohort of 1,457 patients after kidney transplantation from all transplant centres in Slovakia over a period of ten years from 2005 – 2015.The parameters taken into account were cause of end-stage renal disease (ESRD), outcome of transplantation in a context of differences between the genders.

Results: During the ten-year period there were 557 transplanted women vs. 900 men. Among female recipient the dominant cause of ESRD was tubulointerstitial nephritis (males 22.3% vs. females 32.1%, p < 0.0001), other causes of ESRD where females were significantly more represented than men included polycystic kidney disease (males 11.6% vs. females 17.6%, p = 0.0013) and systemic lupus erythematosus (males 0.2% vs. females 2.3 %, p = 0.0001). There was no significant difference in 12-month, 5-year, and 10-year both graft and patient survival rates between men and women. Female recipients wait for kidney transplantation significantly longer in spite of comparable time spent on dialysis (males 32.9 months vs. females 39.4 months, p < 0.0001).

Conclusion: Despite comparable patient and graft survival rates in male and female recipients in our study there are other studies showing that gender as well as gender mismatch significantly influence the outcomes of transplantation.

Nonimmunologic Donor-Recipient Pairing, HLA Matching, and Graft Loss in Deceased Donor Kidney Transplantation

Background

In kidney transplantation, nonimmunologic donor-recipient (D-R) pairing is generally not given the same consideration as immunologic matching. The aim of this study was to determine how nonimmunologic D-R pairing relates to independent donor and recipient factors, and to immunologic HLA match for predicting graft loss.

Methods

Seven D-R pairings (race, sex, age, weight, height, cytomegalovirus serostatus, and HLA match) were assessed for their association with the composite outcome of death or kidney graft loss using a Cox regression-based forward stepwise selection model. The best model for predicting graft loss (including nonimmunologic D-R pairings, independent D-R factors, and/or HLA match status) was determined using the Akaike Information Criterion.

Results

Twenty three thousand two hundred sixty two (29.9%) people in the derivation data set and 9892 (29.7%) in the validation data set developed the composite outcome of death or graft loss. A model that included both independent and D-R pairing variables best predicted graft loss. The c-indices for the derivation and validation models were 0.626 and 0.629, respectively. Size mismatch (MM) between donor and recipient (>30 kg [D < R} and >15 cm [D < R]) was associated with poor patient and graft survival even with 0 HLA MM, and conversely, an optimal D-R size pairing mitigated the risk of graft loss seen with 6 HLA MM.

Conclusions

D-R pairing is valuable in predicting patient and graft outcomes after kidney transplant. D-R size matching could offset the benefit and harm seen with 0 and 6 HLA MM, respectively. This is a novel finding.

Characterization of Potentially Unsafe Ambulatory Antibiotic Use and Associated Outcomes in an Adult Kidney Transplant Population

BACKGROUND

Antibiotics are frequently prescribed to kidney transplant (KTX) recipients in the outpatient setting, but there are limited data assessing the safety and outcomes associated with this practice.

OBJECTIVE

The primary objective of this study was to describe ambulatory antibiotic prescribing in a large cohort of adult KTX recipients. The secondary objective was to assess the outcomes associated with potentially unsafe antibiotic use in this population.

METHODS

National Veterans Health Administration data compiled between 2001 and 2010 were used to conduct a pharmacovigilance assessment of antibiotic prescribing, excluding intravenous agents, antifungals, antivirals, and prophylactic regimens. Multivariable Cox proportional hazard regression was used to determine the impact of safe and potentially unsafe antibiotic use on time to event for graft loss.

RESULTS

Among 5130 KTX recipients and 30 127 patient-years of follow-up, 14 259 antibiotic courses were prescribed at a rate of 0.47 courses per patient-year. Transplant or nephrology providers prescribed 24.8% of courses. Overall, 608 courses (4.3%) in 311 patients (6.1%) were considered potentially unsafe for dosages in disagreement with recommended adjustments for renal function, interaction with immunosuppressive regimens, and other pertinent safety concerns. After adjusting for baseline characteristics, unsafe antibiotic use was associated with a 40% higher risk of graft loss (adjusted hazard ratio = 1.40; 95% CI = 1.03-1.89; P = 0.030) compared with safe use.

CONCLUSIONS AND RELEVANCE

Although unsafe antibiotic prescribing was uncommon, it was associated with increased risk of graft loss. Prospective research is needed to elucidate whether the driver of poor outcomes is the safety of the antibiotic prescription or fragmented care.

The impact of donor and recipient weight incompatibility on renal transplant outcomes

BACKGROUND

Donor/recipient size mismatching and correlation to allograft outcome remains poorly defined. This study assessed the impact of donor body weight (DBW) to recipient body weight (RBW) ratio on allograft function and survival.

METHODS

A total of 898 deceased donor renal transplant recipients were included in the study. Patients were divided into quartiles depending on the ratio of DBW/RBW: Q1 (≤ 0.88), Q2 (0.89-1.00), Q3 (1.01-1.22) and Q4 (> 1.22). Donor and recipient characteristics were obtained from the national kidney transplant service database. Serum creatinine and estimated glomerular filtration rate (eGFR) at 1 and 5 years after transplant were compared.

RESULTS

Q4 patients had a higher eGFR 1 year post-transplant (median 59.5 ml/min, IQR 46.8-76.2) compared to Q1-Q3 which had median eGFRs of 54.3, 54.8 and 55.3 ml/min, respectively (p < 0.001). At 5 years post-transplant, there were modest differences in the eGFR across the four quartiles, Q1-4 with median eGFRs of 56.9, 61.1, 61.2 and 58.6 ml/min, respectively (p = 0.02). However, there were no significant differences in 1- and 5-year allograft survival between groups.

CONCLUSIONS

In the setting of deceased donor renal transplantation, mismatching of donor to recipient weight had no impact on 5-year allograft survival, but a low DBW/RBW ratio is modestly associated with lower eGFR.

Role of Kidneys in Sex Differences in Angiotensin II-Induced Hypertension

The significance of kidneys in regulation of sodium and water balance and hemodynamics has been demonstrated both in patients and animal models. In the present study, we tested our hypothesis that kidneys play an essential role in control of sex differences in angiotensin II (Ang II)-dependent hypertension. Kidney transplantations (KTXs) were performed between male (M) and female (F) C57BL/6 mice (donor→recipient: F→F, M→M, F→M, and M→F). Radiotelemetry transmitters were implanted for measurement of mean arterial pressure during the infusion of Ang II (600 ng·kg^-1·min^-1). Gene expressions and inflammatory responses in the transplanted grafts were assessed. We found that same-sex-KTX mice still exhibited sex differences in Ang II-dependent hypertension (31.3±0.8 mm Hg in M→M versus 12.2±0.6 mm Hg in F→F), which were reduced between males and females when they received kidneys of the opposite sex (32.9±1 mm Hg in M→F versus 22.3±0.7 mm Hg in F→M). The sex differences in gene expressions, including AT₁R (angiotensin II receptor, type 1), AT₁R/AT₂R, ET-1 (endothelin-1), ETA (endothelin receptor type A), NHE3 (sodium-hydrogen exchanger 3), α-ENaC (α-epithelial sodium channel), and γ-ENaC, were unaltered in same-sex KTXs and much lessened in cross-sex KTXs. In addition, the cross-sex KTXs exhibited more robust inflammatory responses reflected by higher expression of IL-6 (interleukin 6), TNFα (tumor necrosis factor α), and KC (keratinocyte-derived chemokine) than same-sex KTX. Our results indicate that kidneys play an essential role in sex differences of Ang II-dependent hypertension. KTX of male kidneys to females augmented the blood pressure response, whereas KTX of female kidneys to males attenuated the blood pressure response. The host's extrarenal systems modulate expressions of many genes and inflammatory response, which may also contribute to the sex differences in blood pressure regulation.

Impact and Application of Donor/Recipient Body Surface Area on Kidney Transplantation from Pediatric Donor to Adult Recipient

BACKGROUND

Insufficient nephron dosing is closely associated with poor graft function and graft loss. Donor/recipient body surface area (D/R BSA) has been proven to be one of the useful predictors for sufficient nephron dosing. However, little is known regarding the impact and application of D/R BSA on kidney transplantation from pediatric donor to adult recipient.

METHODS

We retrospectively analyzed 26 cases of kidney transplantations from pediatric donors to adult recipients, which were performed in our center from 2010 through 2014. Patients were divided into 2 groups based on D/R BSA: group A, <0.8; and group B, ≥0.8. All recipients received a single kidney. Demographics of donors and recipients, early postoperative complications, estimated glomerular filtration rate (eGFR), and short-term (≤1 y) graft survival were compared between groups to evaluate the impact of D/R BSA on kidney transplantations from pediatric donors.

RESULTS

All demographics and early postoperative complications of group A were similar to those of group B (P > .05). eGFR in group A and group B at 1, 3, 6, and 12 months after transplantation were: 63.2 ± 5.0 vs 74.0 ± 7.6 (P = .008), 66.2 ± 4.9 vs 75.8 ± 5.9 (P = .004), 69.0 ± 4.8 vs 79.0 ± 6.3 (P = .004), and 69.4 ± 7.9 vs 79.2 ± 8.4 (P = .033). Short-term graft survival of group A was inferior to that of group B (62.5% vs 94.4%; P = .042).

CONCLUSIONS

We conclude that recipients with high D/R BSA are more likely to have better graft function. It is possible to make optimal allocation of pediatric donor kidneys on the basis of D/R BSA ≥0.8.

Donor-Recipient Weight and Sex Mismatch and the Risk of Graft Loss in Renal Transplantation

BACKGROUND AND OBJECTIVES

Relatively smaller kidney donor to recipient size is proposed to result in higher graft loss due to nephron underdosing and hyperfiltration injury, but the potentially additive effect of sex and weight mismatch has not been explored in detail. The purpose of this study was to determine if concurrent donor and recipient absolute weight and sex mismatch was associated with graft loss in a cohort of deceased donor kidney transplant recipients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The association of kidney donor and recipient absolute weight and sex difference with death-censored graft loss was explored using a cohort of United States deceased donor recipients between 2000 and 2014 through the Scientific Registry of Transplants Recipients. Donor-recipient sex pairings (male donor-male recipient; female donor-female recipient; male donor-female recipient; female donor-male recipient) were further stratified by donor and recipient absolute weight difference (>30 or 10-30 kg [donorrecipient] or <10 kg [donor=recipient]) resulting in 20 weight and sex pairings. Time to death-censored graft loss for each pairing was evaluated using multivariable Cox proportional hazards models adjusting for donor, immunologic, surgical, and recipient predictors of graft loss compared with the reference group of male donor-male recipients with no weight mismatch (<10 kg difference).

RESULTS

Of 115,124 kidney transplant recipients, 21,261 developed death-censored graft failure (median graft survival time was 3.8 years; quartile 1 to 3, 0.0 to 14.8 years). After multivariable adjustment, the highest relative hazards for graft failure were observed for female recipients of male donor kidneys and male recipients of female donor kidneys in situations where the recipient was >30 kg larger than donor (hazard ratio, 1.50; 95% confidence interval, 1.32 to 1.70; hazard ratio, 1.35; 95% confidence interval, 1.25 to 1.45, respectively).

CONCLUSIONS

A concurrent mismatch in donor-recipient weight (donor Collapse

Key Words

• United States
• female
• graft failure
• graft survival
• kidney
• kidney transplantation
• male
• nephrons
• proportional hazards models
• registries
• sex characteristics
• sex mismatch
• size mismatch
• tissue donors
• transplant recipients

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MESH Headings

• Adult
• Body Weight
• Cohort Studies
• Female
• Graft Survival
• Humans
• Kidney Transplantation/statistics & numerical data
• Male
• Middle Aged
• Proportional Hazards Models
• Registries
• Risk Factors
• Sex Factors
• Tissue Donors
• Transplant Recipients
• United States

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Affiliation(s)

Amanda J. Miller Department of Medicine, Division of Nephrology, and
Bryce A. Kiberd Department of Medicine, Division of Nephrology, and
Ian P. Alwayn Department of General Surgery, Nova Scotia Health Authority, Halifax, Nova Scotia, Canada; and
Ayo Odutayo Centre for Statistics in Medicine, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
Karthik K. Tennankore Department of Medicine, Division of Nephrology, and

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[The effect of gender on the results of related kidney transplantation]

AIM

To define the effect of donor and recipient gender on the results of kidney transplantation from living related donor.

MATERIAL AND METHODS

Group of 271 patients who underwent kidney transplantation from living related donor was analyzed. There were 115 women and 156 men. Age varied from 1 to 63 years (mean 21.30±12.32). There were 127 children aged 1-18 years (mean 11.28±4.63) and 144 adults aged 19-63 years (mean 29.81±11.24). Donors included 162 women and 109 men. Overall survival was calculated using Kaplan-Mayer. Mortality and incidence of transplants failure were determined using Fisher's exact test.

RESULTS

All patients were divided into 2 groups depending on recipients' gender and then into 4 subgroups depending on gender of donors and recipients. Comparative statistical analysis showed that transplants survival was higher in women vs. men (T=2.7, p=0.007). Survival of patients was similar in both groups. Moreover it was the best in subgroup of recipients-women with kidneys from donors-men. Difference was statistically significant (T=2.16, p=0.03). There was no significant difference in all other cases.

CONCLUSION

The results of kidney transplantation are better in recipients-women than in men.

Organ transplantation and gender differences: a paradigmatic example of intertwining between biological and sociocultural determinants

Organ transplantation, e.g., of the heart, liver, or kidney, is nowadays a routine strategy to counteract several lethal human pathologies. From literature data and from data obtained in Italy, a striking scenario appears well evident: women are more often donors than recipients. On the other hand, recipients of organs are mainly males, probably reflecting a gender bias in the incidence of transplant-related pathologies. The impact of sex mismatch on transplant outcome remains debated, even though donor-recipient sex mismatch, due to biological matters, appears undesirable in female recipients. In our opinion, the analysis of how sex and gender can interact and affect grafting success could represent a mandatory task for the management of organ transplantation.

Improved renal ischemia tolerance in females influences kidney transplantation outcomes

Experimentally, females show an improved ability to recover from ischemia-reperfusion injury (IRI) compared with males; however, this sex-dependent response is less established in humans. Here, we developed a series of murine renal ischemia and transplant models to investigate sex-specific effects on recovery after IRI. We found that IRI tolerance is profoundly increased in female mice compared with that observed in male mice and discovered an intermediate phenotype after neutering of either sex. Transplantation of adult kidneys from either sex into a recipient of the opposite sex followed by ischemia at a remote time resulted in ischemia recovery that reflected the sex of the recipient, not the donor, revealing that the host sex determines recovery. Likewise, renal IRI was exacerbated in female estrogen receptor α-KO mice, while female mice receiving supplemental estrogen before ischemia were protected. We examined data from the United Network for Organ Sharing (UNOS) to determine whether there is an association between sex and delayed graft function (DGF) in patients who received deceased donor renal transplants. A multivariable logistic regression analysis determined that there was a greater association with DGF in male recipients than in female recipients. Together, our results demonstrate that sex affects renal IRI tolerance in mice and humans and indicate that estrogen administration has potential as a therapeutic intervention to clinically improve ischemia tolerance.

Donor kidney glomerular filtration rate and donor/recipient body surface area ratio influence graft function in living related kidney transplantation

OBJECTIVE

This study seeks to account for the possibility that single kidney glomerular filtration rate (SKGFR) and donor/recipient (D/R) body surface area (BSA) ratio could act as cofactors for evaluating potential living related donors.

METHODS

The study population included 204 cases of LKRs with a functional graft that were regularly followed up for more than 2 years. Based on SKGFR and D/R BSA ratio, the recipients were divided into six groups: group A (SKGFR < 40 mL/min, D/R BSA ratio ≤ 0.8), group B (SKGFR < 40 mL/min, 0.8 < D/R BSA ratio < 1.2), group C (SKGFR < 40 mL/min, D/R BSA ratio ≥ 1.2), group D (SKGFR ≥ 40 mL/min, D/R BSA ratio ≤ 0.8), group E (SKGFR ≥ 40 mL/min, 0.8 < D/R BSA ratio < 1.2), and group F (SKGFR ≥ 40 mL/min, D/R BSA ratio ≥ 1.2). The database included donor, recipient, and transplant variables. Renal function of the recipients was recorded at 1 week, 2 weeks, 1 month, 3 months, 6 months, 12 months, and 24 months post-transplantation, respectively.

RESULTS

The declining rate of SCr and graft eGFR in stable periods post-transplantation in group A were always worse than the other five groups, and the difference was statistically significant (p < 0.05). The declining rate of SCr and graft eGFR in stable periods post-transplantation in groups C and F were always better than the other four groups, and the difference was statistically significant (p < 0.05).

CONCLUSIONS

Both SKGFR and D/R BSA ratio should be considered for choosing potential living related donors. Donors with SKGFR < 40 mL/min and D/R BSA ratio ≤ 0.8 should be carefully selected. Satisfactory graft function in donors with SKGFR < 40 ml could be achieved if their D/R BSA ratio is >0.8.

Gender differences in renal transplant graft survival

BACKGROUND/PURPOSE

A long-term retrospective study was conducted to assess the risk factors of renal transplant graft failure focusing on the effects of gender of both the donor and the recipient.

METHODS

Medical records of primary renal transplantation performed in a single transplant hospital were reviewed. Cases of ABO incompatibility, positive cross-matches, or multiple organ transplants were excluded. A total of 766 patient records were reviewed, and variables were analyzed with Kaplan-Meier survival curves and Cox regression to determine the independent factors associated with graft survival.

RESULTS

The overall 5-year graft and patient survival rates were 84.7% and 92.2%, respectively. Univariate analysis showed significantly poorer prognosis in male patients and in those with acute rejection, delayed function, or more mismatches in human lymphocyte antigens. Multivariate analysis with step-wise regression identified three independent prognostic factors for poor graft survival (male gender, acute rejection, and delayed function). The 5-year graft survival rates for female and male patients were 87.9% and 81.3%, respectively. The risk ratio of graft failure for male renal transplant recipients was 1.3732, when compared with that for female patients. The risk ratios for those with acute rejection and delayed function were 1.8330 and 1.5422, respectively.

CONCLUSION

Male gender, in addition to acute rejection and delayed function, was found to be an independent prognostic factor for poor renal transplant survival in this long-term retrospective study.

Donor and recipient size mismatch in adolescents undergoing living-donor renal transplantation affect long-term graft survival

BACKGROUND

Controversies exist in the adult literature regarding the use of kidneys from small donors into larger recipients. Little is known regarding this issue in pediatric kidney transplantation. To assess the impact of donor/recipient size mismatch on long-term renal graft survival in pediatric patients undergoing living-donor renal transplantation.

METHODS

We reviewed the United Network for Organ Sharing database from 1987 to 2010 for adolescent (11-18 years old) patients who underwent primary living-donor renal transplantation. According to donor/recipient body surface area (BSA) ratio, patients were stratified into two categories: BSA ratio <0.9 and ≥0.9. Graft survival rates were compared between these two groups using Kaplan-Meier survival curves and Cox proportional hazards models.

RESULTS

Of the 1880 patients identified, 116 (6.2%) had a donor/recipient BSA ratio <0.9 and 1764 (93.8%) had a donor/recipient BSA ratio ≥0.9 group. BSA ratio <0.9 conferred an increased risk of graft loss (adjusted hazard ratio, 1.61; 95% confidence interval, 1.13-2.27; P=0.008). Patients with a donor/recipient BSA ratio ≥0.9 group had a significantly longer graft survival compared with those with a donor/recipient BSA ratio <0.9 after adjustment for donor age and gender, recipient age, gender, ethnicity, cause of renal failure, as well as clinical factors, such as cold and warm ischemia time and HLA mismatch.

CONCLUSION

We conclude that low donor/recipient BSA ratio was associated with an increased risk of graft loss. Appropriate size matching conferred better long-term graft survival in adolescents receiving live-donor kidney transplants.

The effect of donor-recipient gender mismatch on short- and long-term graft survival in kidney transplantation: a systematic review and meta-analysis

BACKGROUND

There is no limitation of gender matching in renal transplantation. This study was intended to evaluate its effect on short- and long-term graft survival.

METHODS

PubMed, the Web of Knowledge, Medline, the Cochrane Library, and two additional Chinese databases were searched. The data were then abstracted and meta-analyzed.

RESULTS

14 studies involving 445 279 patients were included. Each study reported data on the four gender matches (male donor-male recipient, MDMR; male donor-female recipient, MDFR; female donor-male recipient, FDMR; female donor-female recipient, FDFR). The pooled risk ratios (RRs) for 0.5-, 1-, 2-, 3-, 5-, and 10-yr graft survival rates showed that the FDMR group had the worst outcomes, and when recipients were female, short-term graft survival was worse, but long-term graft survival was better. The differences between groups changed with time.

CONCLUSIONS

FDMR patients showed poor graft survival. The female recipients had worse short-term graft survival but the best long-term graft survival. This study introduces an important consideration into donor-recipient matching in renal transplantation.

Influence of donor-recipient gender mismatch on graft function and survival following lung transplantation

OBJECTIVES

In current practice, donors and recipients are not matched for gender in lung transplantation. However, some data have suggested a possible effect of gender combinations on lung transplant outcomes. We examined whether donor-recipient (D/R) gender mismatch is related to adverse outcomes after lung transplantation in terms of early and long-term graft function and survival.

METHODS

We reviewed 256 donors and lung transplant recipients over a 14-year period. Patients were distributed into four groups: Group A (D/R: female/female), Group B (D/R: male/male), Group C (D/R: female/male), Group D (D/R: male/female). Donor and recipient variables were compared among groups, including early graft function, 30-day mortality, freedom from bronchiolitis obliterans syndrome (BOS), and long-term survival.

RESULTS

Group A: 57 (22%), Group B: 99 (39%), Group C: 62 (24%), Group D: 38 (15%) transplants (P = 0.001). Donor age was 29 ± 14, 27 ± 12, 33 ± 13 and 23 ± 12 years for Groups A, B, C and D, respectively (P = 0.004). Recipient age was 31 ± 15, 44 ± 17, 42 ± 16 and 30 ± 16 years for Groups A, B, C and D, respectively (P = 0.000). PaO2/FiO2 (mmHg) 24 h post-transplant was: Group A: 276 ± 144, Group B: 297 ± 131, Group C: 344 ± 133 and Group D: 238 ± 138 (P = 0.015). Primary graft dysfunction developed in 23, 14, 17 and 21% of recipients from Groups A, B, C and D, respectively (P = 0.45). Operative mortality was 4.4, 6.5, 5.2 and 2%, for recipients from Groups A, B, C and D, respectively (P = 0.66). Freedom from BOS was 73, 59 and 36% for gender-matched transplants vs 76, 67 and 40% for gender-mismatched transplants at 3, 5 and 10 years, respectively (P = 0.618), without differences among groups. A non-significant survival benefit was observed for female recipients, irrespective of the donor gender.

CONCLUSIONS

Donor-recipient gender mismatch does not have a negative impact on early graft function and mortality following lung transplantation. There is a trend towards a survival benefit for female recipients, irrespective of the donor gender.

Gender disparity of living donor renal transplantation in East China

Gender disparity among living kidney donors is common world wide, which demonstrates different social and economic problems in different countries. However, few data are available for China. Therefore, we retrospectively analyzed all 139 living donor renal transplants performed in our center between 2003 and 2010. The annual number of living donor renal transplants increased from six to 26 cases per year during the observation period. Among them, 69.2% of all kidney donors were females, whereas 79.5% of the recipients were male. The average age of recipients was 34.1 ± 7.6 yr and 94% (110/117) were younger than 44 yr. In contrast, 53% (62/117) of all donors were "middle-aged" (45-59 yr) with an average donor age of 47.8 ± 9.2 yr. The first-degree relatives accounted for the majority of the donor pool, as the most common donor-recipient combination consisted of mother to son. In conclusion, there was a male and young preponderance among recipients, and a female and middle-aged one among donors of living kidney transplants in our transplant center, which might be related to socio-cultural as well as economic factors.