Application of Combined Donor-Derived Cell-Free DNA and Transcriptome in Diagnosis of Kidney Transplant Rejection.

BACKGROUND: Transcriptomic kidney profile testing and donor-derived cell-free DNA (dd-cfDNA) testing are new methods shown to provide early markers of graft inflammation during the post-transplant period. This study focused on utilizing clinical data to evaluate the application of these tests in detecting transplant rejection by comparing tests results to biopsy reports. MATERIAL AND METHODS: We conducted a retrospective analysis of a prospectively collected database of all adult kidney transplant patients at SUNY Upstate Medical Hospital from 1 January 2014 to 1 December 2022. Inclusion criteria were patients with concurrent transcriptomic kidney profile test and kidney biopsy results. RESULTS: Biopsies identified 33 kidney transplant rejections. For diagnosis of kidney rejection, transcriptomic kidney profile testing had a 52.83% positive predictive value and 92.77% negative predicative value, while dd-cfDNA testing had a 54.83% positive predictive value and 86.45% negative predictive value. Transcriptomic kidney profile testing showed an 82.35% sensitivity and 75.49% specificity, while dd-cfDNA testing showed a 56.66% sensitivity and 85.56% specificity. Positive transcriptomic kidney profile and dd-cfDNA tests detected 51.51% of rejections. Combined negative tests were observed in 70.21% of biopsies without rejection. CONCLUSIONS: Despite certain discrepancies and limitations, we believe transcriptomic profile testing and dd-cfDNA testing are useful for detecting early-stage rejections and can guide patient care. Additionally, dd-cfDNA testing avoids invasive screening biopsies. Following negative test results, the probability patients are not having rejection is 86.45%. The transcriptomic profile test's high sensitivity and specificity allow possible detection of transplant rejections that may have otherwise not been identified by biopsy.

Belatacept based immunosuppression: What and when to combine?

INTRODUCTION: This study examines the effect of belatacept based salvage regimens on kidney transplant outcomes. METHODS: This single-center retrospective study included all adult kidney transplant recipients between 2011 and 2022 who were converted to belatacept salvage therapy during their follow up. eGFR, graft survival, incidence of infections and neoplasia, histology and DSA data were collected through systematic review of the medical record. RESULTS: Patients were divided into 3 groups based on salvage regimen: Mycophenolate mofetil/belatacept (MMF/Bela) (n = 28), low-dose Calcineurin inhibitors/belatacept (CNI/Bela) (n = 22), and low-dose Calcineurin inhibitors/ Mycophenolate mofetil /belatacept (CNI/MMF/Bela) (n = 13). Patients with antibody-mediated rejection were more likely to receive CNIs in addition to belatacept (low-dose CNI/MMF/Bela 54%, low-dose CNI/Bela 45%, MMF/Bela 3.6%, p < 0.001). DSA decreased in all groups after transition to belatacept by 15.67% (p = 0.15). No difference in Glomerular filtration rate (eGFR) over time was observed between the groups, and eGFR remained stable over the first year after transition to belatacept. The incidence of death and allograft failure was similar between the groups (low- dose CNI/MMF/Bela n = 3, low-dose CNI/Bela n = 7, MMF/Bela n = 4; p = 0.41). Patients in the low-dose CNI/Bela cohort who were transitioned to belatacept within 6 months from transplant showed a decline in eGFR over the first year after transition, while the other treatment cohorts demonstrated stable or slight increase in eGFR. CONCLUSIONS: The present study demonstrates comparable transplant outcomes in terms of eGFR, graft survival, incidence of infections and neoplasia, rejection rate and donor specific antibody (DSA) in three belatacept-based maintenance immunosuppression regimens supporting the safety and efficacy of these therapeutic options.

Immunosuppression regimen modification during COVID-19 infection in kidney transplant recipients.

BACKGROUND: COVID-19 pandemic had tremendously affected all the aspects of human life during the past 3 years. In this study, we focused on kidney transplant patients' course from the COVID-19 diagnosis, immunosuppressive medication modification, hospitalization, and COVID-19 complications and how the COVID-19 infection affected the kidney and patients' quality of life during the hospitalization and after the discharge. MATERIAL AND METHOD: A retrospective analysis of a prospectively collected database of all kidney transplants adult patients who had a positive COVID-19 PCR from 1 January 2020 to 30 December 2022, and had a history of kidney transplant at the SUNY Upstate Medical Hospital was done to identify the cases. RESULTS: 188 patients met the inclusion criteria and were included in the study. Based on the immunosuppressive regimen modification during COVID-19 infection, patients divided into two groups; in 143 (76%) patients, the immunosuppressive medication was reduced, and in 45 (24%) of patients, the immunosuppressive regimen continued as before during the COVID-19 infection. The mean time from the transplant to the diagnosis of COVID-19 was 67 months in the group we reduced the IM regimen, and 77 months in the group without changes in IM regimen. The mean recipients' age was 50.7 ± 12.9 years in the group we reduced the IM regimen, and 51.8 ± 16.4 years in the group without changes in IM regimen (P = 0.64). The vaccination rate against COVID-19 with at least 2 doses of either the CDC recommended Moderna or Pfizer vaccines was 80.2% in the group we reduced the IM regimen, and 84.8% in the group without changes in IM regimen (P = 0.55). The hospitalization rate due to COVID-19 related symptoms was 22.4% % in the group we reduced the IM regimen, and 35.5% in the group without changes in IM regimen (P = 0.12). However, the ICU admission rate was higher in the group we reduced the IM regimen, but the difference was not significant (26.5% Vs.6.25%, P = 0.12). 6 episodes of biopsy-proven rejection in the group with IM reduction was observed, which were 3 episodes of acute antibody-mediated rejections (ABMR) and 3 episodes of acute T-Cell-mediated rejections (TCMR), and 3 episodes in the group without any change in IM regimen, which were 2 episodes of ABMR and 1 episode of TCMR (P = 0.51). No significant difference was mentioned in the eGFR and serum creatinine after the comparison between the groups after 12 months of follow up. 124 patients responded to the post-COVID-19 questionnaires and were included in the data analysis. The response rate was 66%. Fatigue and exertion were the most reported symptom with a 43.9% prevalence. CONCLUSIONS: We found that immunosuppressive regimen minimization did not impact the kidney function in the long-term and it might be a helpful strategy to minimize the effect of COVID-19 infection on patients' condition during the hospital stay. With all the treatments, vaccinations, and precautions, still some patients did not achieve the complete recovery compared to their pre-COVID-19 health status. Fatigue was the main reported symptom amongst all the reported symptoms.

Early conversion to belatacept-based immunosuppression regimen promotes improved long-term renal graft function in kidney transplant recipients.

BACKGROUND: Belatacept has been demonstrated as an effective alternative immunosuppressant in kidney transplant recipients. This study focuses on outcomes of early and late conversion to Belatacept-based immunosuppression after kidney transplant. MATERIALS AND METHODS: This retrospective analysis of a prospectively collected database included all adult kidney transplants patients at SUNY Upstate Medical Hospital from 1 January 2014 to 30 December 2022. Early conversion was defined as all conversions done at <6 months after kidney transplantation, and late conversion to belatacept was defined as conversion at >6 months after kidney transplantation. RESULTS: Out of 61 patients included in this study, 33 patients (54%) were in the early conversion group, and 28 patients (46%) were in the late conversion group. The mean eGFR in the early conversion group was 26.73 ± 16.26 ml/min/1.73 m2 before conversion to belatacept, which improved to 45.3 ± 21.01 ml/min/1.73 m2 at one-year post-conversion (p = 0.0006). Furthermore, eGFR changes in the late conversion group were insignificant, with 46.30 ± 15.65 ml/min/1.73 m2 before conversion to belatacept, and 44.76 ± 22.91 ml/min/1.73 m2 after one year of follow-up (p = 0.72). All four biopsy-proven allograft rejections in the early conversion group were acute T-cell-mediated rejections (ATMR). In the late conversion group, out of three biopsy-proven rejections, one was chronic antibody-mediated rejection (CAMR), one was ATMR, and one was mixed ATMR/CAMR. All four patients with ATMR rejection received mycophenolic acid (MPA) as part of their immunosuppressive regimen, and none received tacrolimus. The one-year post-conversion allograft survival rate in early and late conversion groups was 100%. However, the one-year post-conversion patient survival rate was 90.9% in the early conversion group and 100% in the late conversion group (P = 0.11). CONCLUSIONS: Early post-transplant conversion to belatacept can improve the eGFR more meaningful when compared to late conversion. Patients who receive belatacept and MPA rather than tacrolimus may have increased rates of T-cell-mediated rejection.

Conversion to Belatacept in kidney transplant recipients with chronic antibody-mediated rejection (CAMR).

BACKGROUND: The costimulatory inhibitor Belatacept (Bela) has been shown to be an effective alternative in several clinical situations, including chronic antibody-mediated rejection, calcineurin toxicity, and de novo alloantibody formation. To further explore the usefulness of Belatacept under various clinical scenarios, we performed a retrospective analysis of a prospective database of all recipients who had a BPAR diagnosis of CAMR and were converted to a Belatacept maintenance immunosuppression regimen after kidney transplantation. MATERIAL AND METHOD: We conducted a retrospective analysis of a prospectively collected database of all kidney transplants adult patients at SUNY Upstate Medical Hospital from 1 January 2013 to 31 December 2021. Our inclusion criteria were the patients who have been diagnosed with CAMR according to their renal biopsy based on the 2013 Banff criteria. The primary objective was to compare the kidney viability and function using GFR between the two interest groups and finally compare the outcomes. RESULTS: A total of 48 patients met our inclusion criteria based on the kidney biopsy result, which showed chronic antibody-mediated graft rejection (CAMR). Nineteen patients (39.6%) were converted to the Belatacept, and we continued the previous immunosuppression regimen in 29 patients (60.4%). The mean time from the transplant date to the diagnosis of CAMR was 1385 days in the Belatacept group and 914 days for the non-Belatacept group (P = 0.15). The mean GFR comparison at each time point between the groups did not show a significant difference, and Belatacept did not show superiority compared to the standard immunosuppression regimen in terms of kidney function preservation. 1 (5.2%) patient from the Belatacept group and 1 (3.4%) patient from the non-Belatacept group had a biopsy-proven acute rejection (BPAR) after CAMR confirmation, and it was comparable (P = 0.76). De novo synthesis of the DSA rate was 12.5% in the Belatacept group and 15% In the non-Belatacept group, which was comparable. (P = 0.90). The patient survival rate was 100% in both groups. CONCLUSIONS: We conclude that compared to the standard Tacrolimus/MMF/Prednisone regimen, Belatacept did not significantly benefit in preserving the GFR in long-term follow-ups and stabilizing the DSA production, which is one of the main factors resulting in chronic graft failure.