Influence of donor and recipient gender as well as selected factors on the five-year survival of kidney graft

Immunologic Outcomes in Cross-Sex Solid Organ Transplants: A Systematic Review and Meta-Analysis to Inform Vascularized Composite Allotransplantation

BACKGROUND

Of nearly 90 hand and 50 face transplant recipients, only five have received a cross-sex vascularized composite allotransplantation (CS-VCA). CS-VCA has the potential to expand the donor pool and has been proven anatomically feasible and ethically acceptable in previous studies. However, there is a lack of immunologic data. This study evaluated the immunologic feasibility of CS-VCA through analysis of the solid organ transplant literature, given the paucity of CS-VCA data. The authors hypothesize that rates of acute rejection (AR) and graft survival (GS) in CS versus same-sex (SS) solid organ transplantation are similar.

METHODS

A systematic review and meta-analysis were performed. Studies comparing GS or AR episodes in CS and SS adult kidney (KT) and liver transplant (LT) populations were included. Odds ratios were calculated for overall GS and AR for all SS and CS transplant combinations [male-to-female (MTF), female-to-male, and overall].

RESULTS

A total of 693 articles were initially identified with 25 included in the meta-analysis. No significant difference in GS was noted between SS-KT versus CS-KT [OR, 1.04 (95% CI, 1.00 to 1.07); P = 0.07), SS-KT versus MTF-KT [OR, 0.97 (95% CI, 0.90 to 1.04); P = 0.41), and SS-LT versus MTF-LT [OR, 0.95 (95% CI, 0.91 to 1.00); P = 0.05). No significant difference in AR was noted between SS-KT versus MTF-KT [OR, 0.99 (95% CI, 0.96 to 1.02); P = 0.57), SS-LT versus CS-LT [OR, 0.78 (95% CI, 0.53 to 1.16); P = 0.22], or SS-LT versus female-to-male LT [OR, 1.03 (95% CI, 0.95 to 1.12); P = 0.47]. For the remaining pairings, GS was significantly increased and AR was significantly decreased in the SS transplants.

CONCLUSIONS

Published data suggest immunologic feasibility of CS-KT and CS-LT with the potential for generalization to the VCA population.

CLINICAL RELEVANCE STATEMENT

In theory, CS-VCA could expand the potential donor pool, ultimately leading to decreased wait times for recipients and improve the likelihood of establishing a immunologically favorable donor-recipient match.

Impact of Sex Disparities on Outcomes of Living-Donor Kidney Transplant in Egypt: Data of 979 Patients

OBJECTIVES

Renal transplant is the criterion standard for treatment of end-stage renal disease. The effects of disparities between men and women on renal transplant outcomes have been evaluated in many studies but with debatable results. It has been suggested that female kidney donors have poor outcomes after transplant compared with male kidney donors, especially when implanted in a male recipient. The aim of the study was to evaluate the effects of sex on living-donor kidney transplant outcome.

MATERIALS AND METHODS

The data of 979 patients who underwent living-donor kidney transplant from January 2000 to December 2010 at a single center were reviewed retrospectively. The patients were divided into 4 groups according to recipient and donor sex: male donor-to-male recipient (n = 307), male donor-to-female recipient (n = 132), female donor-to-male recipient (n = 411), and female donor-to-female recipient (n = 129). We compared the demographic characteristics, posttransplant rejection and complications, and graft and patient survival rates among the groups.

RESULTS

Male recipients were older than female recipients, whereas male donors were younger than female donors (P < .001). No statistically significant differences were shown regarding recipient body mass index, ischemia time and time to diuresis, and acute and chronic rejection rates between the groups. Graft (P = .947) and patient (P = .421) survival rates were comparable between groups.

CONCLUSIONS

Donor and recipient sex had no significant effect on outcomes of living-donor renal allograft recipients.

Cross-sex transplantation alters gene expression and enhances inflammatory response in the transplanted kidneys

Kidney transplantation (KTX) is a life-saving procedure for patients with end-stage renal disease. Expression levels of many genes in the kidney vary between males and females, which may play an essential role in the sex differences in graft function. However, whether these differences are affected after cross-sex-KTX is unknown. In the present study, we assessed postoperative changes in genotype, function, and inflammatory responses of the grafts in same-sex- and cross-sex-KTX. Single kidney transplants were performed between same and different sex C57BL/6 mice paired into four combination groups: female donor/female recipient (F/F); male donor/male recipient (M/M); female donor/male recipient (F/M); and male donor/female recipient (M/F). The remnant native kidney was removed 4 days posttransplant. Expression levels of genes related to the contractility of the afferent arteriole and tubular sodium reabsorption were assessed. Same-sex-KTX did not significantly alter the magnitude or sex difference pattern of gene expression in male or female grafts. Cross-sex-KTX showed an attenuated sex difference in gene expressions. The measurements of endothelin 1, endothelin ET_A receptor, Na⁺-K^--2Cl cotransporter 2 (NKCC2), and epithelial Na⁺ channels (ENaC) subunits exhibited decreases in M/F compared with M/M and increases in F/M compared with F/F. There were no significant differences in hemodynamics or sodium excretion in response to acute volume expansion for any sex combinations. Cross-sex-KTX stimulated more robust inflammatory responses than same-sex-KTX. IL-6 and KC mRNA levels elevated 5- to 20-fold in cross-sex-KTX compared with same-sex-KTX. In conclusion, cross-sex-KTX alters gene expression levels and induces inflammatory responses, which might play an important role in long-term graft function.

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.

Gender in the allocation of organs in kidney transplants: meta-analysis

OBJECTIVE

To analyze whether gender influence survival results of kidney transplant grafts and patients.

METHODS

Systematic review with meta-analysis of cohort studies available on Medline (PubMed), LILACS, CENTRAL, and Embase databases, including manual searching and in the grey literature. The selection of studies and the collection of data were conducted twice by independent reviewers, and disagreements were settled by a third reviewer. Graft and patient survival rates were evaluated as effectiveness measurements. Meta-analysis was conducted with the Review Manager^® 5.2 software, through the application of a random effects model. Recipient, donor, and donor-recipient gender comparisons were evaluated.

RESULTS

: Twenty-nine studies involving 765,753 patients were included. Regarding graft survival, those from male donors were observed to have longer survival rates as compared to the ones from female donors, only regarding a 10-year follow-up period. Comparison between recipient genders was not found to have significant differences on any evaluated follow-up periods. In the evaluation between donor-recipient genders, male donor-male recipient transplants were favored in a statistically significant way. No statistically significant differences were observed in regards to patient survival for gender comparisons in all follow-up periods evaluated.

CONCLUSIONS

The quantitative analysis of the studies suggests that donor or recipient genders, when evaluated isolatedly, do not influence patient or graft survival rates. However, the combination between donor-recipient genders may be a determining factor for graft survival.

Mortality predictors in renal transplant recipients with severe sepsis and septic shock

Introduction

The growing number of renal transplant recipients in a sustained immunosuppressive state is a factor that can contribute to increased incidence of sepsis. However, relatively little is known about sepsis in this population. The aim of this single-center study was to evaluate the factors associated with hospital mortality in renal transplant patients admitted to the intensive care unit (ICU) with severe sepsis and septic shock.

Methods

Patient demographics and transplant-related and ICU stay data were retrospectively collected. Multiple logistic regression was conducted to identify the independent risk factors associated with hospital mortality.

Results

A total of 190 patients were enrolled, 64.2% of whom received kidneys from deceased donors. The mean patient age was 51±13 years (males, 115 [60.5%]), and the median APACHE II was 20 (16–23). The majority of patients developed sepsis late after the renal transplantation (2.1 [0.6–2.3] years). The lung was the most common infection site (59.5%). Upon ICU admission, 16.4% of the patients had ≤1 systemic inflammatory response syndrome criteria. Among the patients, 61.5% presented with ≥2 organ failures at admission, and 27.9% experienced septic shock within the first 24 hours of ICU admission. The overall hospital mortality rate was 38.4%. In the multivariate analysis, the independent determinants of hospital mortality were male gender (OR = 5.9; 95% CI, 1.7–19.6; p = 0.004), delta SOFA 24 h (OR = 1.7; 95% CI, 1.2–2.3; p = 0.001), mechanical ventilation (OR = 30; 95% CI, 8.8–102.2; p<0.0001), hematologic dysfunction (OR = 6.8; 95% CI, 2.0–22.6; p = 0.002), admission from the ward (OR = 3.4; 95% CI, 1.2–9.7; p = 0.02) and acute kidney injury stage 3 (OR = 5.7; 95% CI,1.9–16.6; p = 0.002).

Conclusions

Hospital mortality in renal transplant patients with severe sepsis and septic shock was associated with male gender, admission from the wards, worse SOFA scores on the first day and the presence of hematologic dysfunction, mechanical ventilation or advanced graft dysfunction.