HLA-identical renal transplant recipients: immunosuppression, long-term complications, and survival

Immunosuppression of HLA identical living-donor kidney transplant recipients: A systematic review

BACKGROUND

Kidney transplant (KT) recipients of HLA identical siblings (HLAid) have lower immunological risk, but there are no specific recommendations for immunosuppression. Our aim was to analyze evidence about results from HLAid living-donor recipients under different immunosuppression in the current era of immunological risk assessment.

METHODS

Systematic review of studies describing associations between outcomes of HLAid living-donor KT recipients according to their immunological risk and applied immunosuppression.

RESULTS

From 1351 studies, 16 (5636 KT recipients) were included in the analysis. All studies were retrospective, ten comparing immunosuppression strategies, and six immunological risk strata. Of those ten, six studies were published in 1990 or earlier and only three included tacrolimus. The evidence is poor, and the inclusion of calcineurin inhibitors does not demonstrate better results. Furthermore, only few studies describe different immunosuppression regimens according to the patient immunological risk and, in general, they do not include the assessment with new solid phase assays.

CONCLUSIONS

There are no studies analyzing the association of outcomes of HLAid KT recipients with current immunological risk tools. In the absence of evidence, no decision or proposal of immunosuppression adapted to modern immunological risk assessment can be made currently by the Descartes Working Group.

Mycophenolate Monotherapy in HLA-Matched Kidney Transplant Recipients: A Case Series of 20 Patients

The ideal minimizing strategy for maintenance immunosuppression in HLA-matched kidney transplant recipients (KTR) is unknown. We hypothesized that mycophenolate (MPA) monotherapy is a safe and effective approach for maintenance therapy in this group of KTR.

Methods

Data were abstracted for 6-antigen HLA-matched KTR between 1994 and 2013. Twenty recipients receiving MPA monotherapy secondary to infection, cancer, calcineurin inhibitor (CNI) side effects, or immunosuppression minimization strategies were evaluated in this case series.

Results

MPA monotherapy had a low incidence of death-censored graft failure (3.19/100 person-y), rejection (0/100 person-y), hospitalization (1.62/100 person-y), malignancy (3.61/100 person-y), and infection (1.75/100 person-y). Further, 12-month mean or median serum creatinine (1.29 mg/dL), estimated glomerular filtration rate (64.3 mL/min/1.73 m2), urine protein creatinine ratio (143.2 mg/g), hemoglobin (13.9 g/dL), platelets (237.8 K/uL), and white blood cell count (9.04 K/uL) were favorable. There was a successful conversion rate of 90% (18 of 20) with 2 patients converting back to CNI-based regimens secondary to recurrence of membranous nephropathy and post-transplant lymphoproliferative disorder.

Conclusions

Our findings indicate that MPA monotherapy may be a promising immunosuppression minimization strategy for HLA-matched KTR.

Immunosuppression and Graft Rejection in Living-related HLA-identical Renal Transplantation: The RADOVFULL Study

BACKGROUND

We aimed to describe the immunosuppressive regimens and graft rejection rates in living-related HLA-identical (LR HLAid) renal transplantation.

METHODS

We performed a retrospective multicenter analysis of the French national database for LR HLAid renal transplantations performed between 2002 and 2012. Univariate and multivariate analysis were performed to determine risk factors for graft rejection in LR HLAid recipients.

RESULTS

A total of 27 218 renal transplantations were performed, of whom 163 had a LR HLAid donor. About immunosuppressive treatment, <60% of the cohort had induction therapy with polyclonal or monoclonal antibodies, 28% did not receive calcineurin inhibitors, and 36% did not receive steroids in maintenance. Biopsy-proven acute rejection was diagnosed in 21 patients (12.9%). Rejection occurred on an average of 24 months after transplantation, in 28.5% of the cases after minimization of immunosuppression. Factors associated with rejection were age of recipient (OR, 0.91 [0.84-0.96]; P = 0.003), the body mass index of donors (odds ratio [OR], 1.22 [1.04-1.46]; P = 0.01), and minimization of immunosuppression (OR, 26.2 [5.48-166.6]; P < 0.001). Overall and graft survival rates were not statistically different according to rejection at 1, 5, and 10 years posttransplantation.

CONCLUSIONS

Minimization of immunosuppression should be done with caution in LR HLAid renal transplantations.

HLA-identical sibling renal transplantation: influence of donor and recipient gender mismatch on long-term outcomes

BACKGROUND

Long-term function of living-related kidney allograft depends on multiple variables. The aim of the present study was to assess the influence of donor and recipient gender mismatch on the short and long-term outcomes in human leukocyte antigen (HLA)-identical sibling renal transplants (SRTs) receiving induction therapy and different immunosuppressive regimens.

MATERIAL AND METHODS

Twenty-nine recipients who were grafted from their HLA-identical siblings between 1994 and 2008 were divided into 2 groups (same and mismatched) according to gender of donor and recipient. The analyzed variables were age, gender, cholesterol, triglyceride, proteinuria, estimated glomerular filtration rate, weight, body mass index, and serum creatinine at 6, 12, 24, 36, 48, and 60 months, and median follow-up. Univariate and multivariate logistic regression models (when appropriate) were used to evaluate the effects of variables on allograft survival.

RESULTS

The number of male donors (P = .001) and recipient age (P = .019) was significantly higher in the same gender group than in mismatched gender group; there were no relationships between remainder analyzed parameters. Multivariate regression analysis revealed that after median follow-up period of 84 months (range, 60-232) the most important potential factors to significantly influence long-term outcomes were male donor (P = .002), recipient age (P < .001), and donor age (P = .021).

CONCLUSION

Our study demonstrated that male donor, and donor and recipient age affected long-term survival of HLA-identical SRTs, supported with antibody induction therapy and lifetime immunosuppression.

Calcineurin inhibitors in HLA-identical living related donor kidney transplantation

BACKGROUND

Given the nephrotoxicity of calcineurin inhibitors (CNIs), we asked whether their addition improved living related donor (LRD) human leukocyte antigen (HLA) identical kidney transplant recipient outcomes.

METHODS

We performed a comprehensive literature review and a single-center study comparing patient survival (PS) and graft survival (GS) of LRD HLA-identical kidney transplants for three different immunosuppression eras: Era 1 (up to 1984): anti-lymphocyte globulin (ALG) induction and maintenance immunosuppression with prednisone and azathioprine (AZA) (n = 114); Era 2a (1984-99): CNI added; evolution from ALG to thymoglobulin; AZA to mycophenolate (n = 262). Era 2b (1999-2011): rapid discontinuation of prednisone (thymoglobulin induction, CNI and mycophenolate) in recipients having first or second transplant and not previously on prednisone (n = 77).

RESULTS

Demographics differed by era: recipient (P < 0.0001) and donor age (P < 0.0001) increased and the proportion of Caucasian donors (P = 0.02) and recipients (P = 0.003) decreased with each advancing era. There was no significant difference in PS (P = 0.6); cause of death (P = 0.5); death-censored GS (P = 0.8) or graft loss from acute rejection by era. Graft loss from chronic allograft nephropathy (P = 0.02) and hypertension (P = 0.005) were greater in the CNI eras. There were no significant differences in the 1/creatinine slopes between eras for the first (P = 0.6), second (P = 0.9) or >2 years post-transplant (P = 0.4). Literature review revealed no clear benefits for CNI in these human leukocyte antigen (HLA) identical LRD graft recipients.

CONCLUSIONS

This study confirmed that there are no benefits of CNIs for HLA-identical LRD recipients. Moreover, we did find evidence of potential harm. Thus, monotherapy or early discontinuation of CNI should be given consideration in these patients.

Long-term mycophenolate monotherapy in human leukocyte antigen (HLA)-identical living-donor kidney transplantation

Although recipients of a first HLA-identical living-donor kidney transplant seem to need less immunosuppression, there are no guideline recommendations for these patients, and few prospective trials are available.

METHODS

We analyzed all PRA-negative patients who received a first kidney transplant from an HLA-identical living donor. The patients received no antibody induction. An intraoperative bolus of 500 mg of methylprednisolone was administered. Then, steroid therapy was withdrawn within one week. Tacrolimus and mycophenolate treatment were started 3 days before transplantation with tacrolimus target levels of 4 to 8 ng/mL. In the absence of rejection, tacrolimus was withdrawn between 3 and 12 months post-transplant to reach mycophenolate mofetil monotherapy of 2 g/day or equivalent.

RESULTS

Six patients were treated with the above protocol. At last follow-up, graft and patient survival were 100%. MDRD glomerular filtration rates were 54, 60, and 62 mL/min at 3 months, 12 months and last follow-up, respectively. None of the patients developed PRA post-transplant. One episode of acute rejection Banff IA occurred 9 years after transplantation due to non-adherence with good outcome after treatment. The mean number of concomitant drugs given with mycophenolate was 2.6. Four patients needed antihypertensive drugs.

CONCLUSION

Steroid-free de novo treatment and calcineurin-inhibitor weaning with mycophenolate monotherapy is feasible in first HLA-identical kidney transplantation from a living sibling.

Successful tapering of immunosuppression to low-dose monotherapy steroids after living-related human leukocyte antigen-identical renal transplantation

BACKGROUND

Living-related (LR) human leukocyte antigen (HLA)-identical renal transplant (RTx) recipients often receive standard immunosuppression, despite the absence of mismatched major HLA-antigens and the known complications of long-term use of immunosuppression. No data are available on the need for immunosuppression for these specific patients. We wondered whether their immunosuppressive load could be radically reduced.

METHOD

Between November 1982 and November 2005, 83 LR HLA-identical RTx were performed in our center. Their unadjusted graft survival was 74% at 10 years. In 29 patients (median time after transplantation 5.6 [range 1.0-21.4] years) with stable uncompromised renal function, we tapered their immunosuppression from triple or dual therapy to prednisolone 5 mg/day. Follow up on prednisolone monotherapy was at least 24 months.

RESULTS

In 27 of 29 patients reduction of immunosuppression to prednisolone monotherapy was uneventful. One patient, using dual therapy, developed JC-virus nephropathy resulting in graft loss. One refused further discontinuation of his medication. Four (15%) of the 27 patients on monotherapy developed biopsy-proven recurrence of their original disease. Only one of them showed a transient decline in renal function. One additional patient developed minor proteinuria and a rise in serum creatinine level, as a result of chronic urinary tract infections. The remaining 23 of 27 patients (85%) had an uneventful follow up during 24 months prednisolone monotherapy.

CONCLUSION

We conclude that HLA-identical LR RTx recipients who are at least 1 year after transplantation might be treated with low-dose steroid monotherapy. Close surveillance of patients for recurrence of their original disease is recommended to allow for potential early therapeutic intervention.

A prospective trial of a steroid-free/calcineurin inhibitor minimization regimen in human leukocyte antigen (HLA)-identical live donor renal transplantation

BACKGROUND

Few prospective trials in human leukocyte antigen (HLA) identical living donor (LD) renal transplantation exist. This prospective study evaluated a corticosteroid (CS)-free, calcineurin inhibitor (CNI) minimization immunosuppressive regimen in HLA-identical LD renal transplant recipients.

METHODS

Twenty HLA-identical LD recipients were prospectively enrolled. Immunosuppression included mycophenolate mofetil (MMF) (2 g/day), tacrolimus (target trough 4-8 ng/mL), sirolimus (target trough 6-10 ng/mL), and no pre- or postoperative steroids. In the absence of prior rejection, tacrolimus was discontinued at posttransplant day 120 and sirolimus at 1 year, leaving patients on MMF monotherapy.

RESULTS

Tacrolimus was successfully withdrawn in 94% of patients (16/17). One hundred percent (15/15) of patients who reached 1-year posttransplant had sirolimus discontinued. Ninety-four percent (17/18) of patients remain off CSs. Mean serum creatinine at 6, 12, and 24 months were 1.38+/-0.32, 1.35+/-0.37, and 1.25+/-0.29 mg/dL; corresponding mean calculated creatinine clearance estimates were 70+/-18, 73+/-17, and 72+/-15 mL/min. Acute cellular rejection, chronic allograft nephropathy, and CNI toxicity were not observed. Death-censored graft survival was 100% at last follow-up.

CONCLUSIONS

A CS-free, CNI minimization immunosuppressive regimen with weaning to MMF monotherapy provides excellent renal function, graft survival, and patient survival in HLA-identical LD renal transplant recipients.