Living Donor Kidney Transplant Recipients Research Articles

Association of PIRCHE-II score with anti-donor T-cell response and risk of de novo donor-specific antibody production in kidney transplant recipients

BackgroundDe novo donor-specific antibodies (dnDSAs) affect long-term outcomes of kidney transplantation (KT). A higher Predicted Indirectly ReCognizable Human Leukocyte Antigen (HLA) Epitopes (PIRCHE-II) score correlates with various clinical outcomes, including dnDSA formation. However, a detailed analysis of the relationship between the PIRCHE-II score and anti-donor T-cell response is lacking. Therefore, this study investigated the relationship between PIRCHE-II scores associated with dnDSA formation and mixed lymphocyte reaction results of anti-donor T-cell response. MethodsData of 105 adult living-donor KT recipients were retrospectively assessed. ResultsOf the 105 patients, 13.3 % developed dnDSAs during the observation period. The PIRCHE-II score at the HLA-DQ locus (PIRCHE-DQ) was significantly higher in patients with dnDSA formation than in those without. The incidence of dnDSA formation was significantly higher in the PIRCHE-DQ ≥ 77 group than in the PIRCHE-DQ < 77 group. The proportion of patients with increased anti-donor T-cell response was significantly higher in the PIRCHE-DQ ≥ 77 group than in the PIRCHE-DQ < 77 group before KT and at 4 and 5 years after KT. ConclusionsPIRCHE-DQ may predict dnDSA formation and anti-donor T-cell response. Reducing the immunosuppressive drug dose in cases of high PIRCHE-DQ might not be prudent.

Isoniazid Prophylaxis Based on Tuberculosis Risk Factors in Living Kidney Transplantation Recipients: A Retrospective Cohort Study

BackgroundTuberculosis (TB) is a major and severe opportunistic infection among solid organ transplant recipients. Chemoprophylaxis is advised for those with latent tuberculosis infection (LTBI). However, the effectiveness of an isoniazid (INH) prophylactic approach based on TB risk factors remains uncertain. MethodsThis study included all living-donor kidney transplant recipients (KTRs) between January 2016 and December 2022. The recipients were categorized into three groups: the risk group with isoniazid (R-INH), the risk group without isoniazid (R-NINH), and the non-risk group (NR), based on the presence of TB risk factors and INH usage. The R-INH group received a 6-month INH prophylactic regimen to prevent post-transplant TB infection. The incidence of active TB among the groups was assessed. ResultsA total of 1348 patients were divided into R-INH (n=108), R-NINH (n=371), and NR (n=869). Forty-seven patients (3.49%) developed TB with an incidence rate of 16.0 per 1000 person-years. Compared to NR, the TB incidence in R-INH was not statistically different (HR, 0.55, 95% CI, 0.07-4.21, P = 0.564), whereas it was significantly higher in R-NINH (HR, 5.04, 95% CI, 2.64-9.62, P < 0.001). The median time from transplantation to TB was 19 months (IQR: 6-39), and 18 patients (38.3%) were diagnosed within one year of transplantation. Ninety-four patients (87.0%) completed INH prophylaxis, with adverse events including two cases of hepatotoxicity (1.85%) and one case of peripheral neuritis (0.93%). ConclusionsA 6-month INH regimen based on TB risk factors is effective and well tolerated for preventing post-transplant TB in KTRs

Basiliximab induction alone vs a dual ATG-basiliximab approach in first live-donor non-sensitized kidney transplant recipients with low HLA matching.

Individualizing induction therapy based on immunological risk is crucial for optimizing outcomes in kidney transplantation. A retrospective analysis included 157 first live-donor non-sensitized kidney transplant recipients (KTRs). Within this cohort, 96 individuals exhibited low human leukocyte antigen (HLA) matching (5-6 HLA mismatches). The low HLA match subgroup was categorized into 52 KTRs receiving basiliximab alone and 44 recipients treated with a combined single ATG dose of 1.5mg/kg and basiliximab. The primary endpoint was early acute cellular rejection (ACR) within 6months post-transplant while secondary outcomes encompassed infection rates, renal allograft function, length of stay (LOS) and readmissions post-transplant. The incidence of early ACR was decreased for low HLA match KTRs, who received ATG-basiliximab, when compared with low HLA-matched KTRs who received basiliximab alone (9.1% vs 23.9%, P=.067). Age was a predictor for rejection, and subgroup analysis showed consistent rejection reduction across age groups. No significant differences were observed in admission for transplant LOS or in peri-operative complications, nor in infections rate including BK and cytomegalovirus viremia, allograft function and number of readmissions post-transplant up to 6months post-transplant. In non-sensitized first live-donor KTRs with low HLA matching, a dual ATG-basiliximab induction approach significantly reduced early ACR without compromising safety.

Perioperative glucose monitoring with continuous glucose monitors identifies risk factors for post-transplant diabetes mellitus in kidney transplant recipients

Post-transplantation diabetes mellitus (PTDM) negatively affects graft and patient survival after kidney transplantation (KT). This prospective study used continuous glucose monitoring (CGM) to evaluate perioperative blood glucose dynamics, identify PTDM risk factors, and compare predictive accuracy with capillary blood glucose monitoring (CBGM) in 60 non-diabetic living-donor KT recipients. Patients underwent 2-week pre- and postoperative CGM, including routine CBGM during their in-hospital stays. PTDM-related risk factors and glucose profiles were analyzed with postoperative CGM and CBG. PTDM developed in 14 (23.3%) patients and was associated with older age, male sex, higher baseline HbA1c, high-density lipoprotein cholesterol, and 3-month cumulative tacrolimus exposure levels. Male sex and postoperative time above the range (TAR) of 180 mg/dL by CGM were PTDM-related risk factors in the multivariate analysis. For predictive power, the CGM model with postoperative glucose profiles exhibited higher accuracy compared with the CBGM model (areas under the curves of 0.916, and 0.865, respectively). Therefore, we found that male patients with a higher postoperative TAR of 180 mg/dL have an increased risk of PTDM. Postoperative CGM provides detailed glucose dynamics and demonstrates superior predictive potential for PTDM than CBGM.

Impact of Dialysis Time on Long-term Outcomes in HLA-identical Living Donor Kidney Transplant Recipients.

Dialysis vintage is associated with worse outcomes after kidney transplantation. The reasons behind this observation include immunological and nonimmunological risk factors. To mitigate the influence of immunological factors, we examined the association between time on dialysis and clinical outcomes in a cohort of HLA-identical kidney transplant recipients. This retrospective study included 13 321 kidney transplant recipients between 1999 and 2016, of whom 589 were HLA identical followed for at least 5 y. Patient and graft survivals were compared according to dialysis time (<12 or >12 mo) using the log-rank test and Cox regression analysis. We compared surgical complications, cytomegalovirus infection, acute rejection, disease recurrence, and the trajectories of estimated glomerular filtration rate (eGFR). Median time on dialysis was 15 mo; 9.2% of patients received preemptive transplants, and 55.3% of patients were on dialysis for >12 mo. After a median follow-up time of 154 mo, there were no differences in unadjusted and adjusted patient and graft survivals (1, 5, 10, and 15 y) between the 2 groups. There were no differences in the incidence of surgical complications (6.2% versus 3.1%), acute rejection (6.1% versus 7.7%), cytomegalovirus infection (7.6% versus 4.0%), and disease recurrence (4.2% versus 4.0%), respectively. There were no differences in mean eGFR during 5 y or in the proportion of patients with an eGFR <30 mL/min at 5 y (9.9% versus 9.2%). In this low immunological risk cohort of HLA-identical kidney transplant recipients, we did not observe any association between dialysis vintage on patient survival and graft survival.

P.134: Assessment of tacrolimus-based vs. cyclosporine-based maintenance immunosuppressive regimens among living donor kidney transplant recipients with low immunological risk: Single centre experience.

P.134: Assessment of tacrolimus-based vs. cyclosporine-based maintenance immunosuppressive regimens among living donor kidney transplant recipients with low immunological risk: Single centre experience.

P.248: Characteristics and outcomes of living donor kidney transplant recipients at King Faisal Hospital Rwanda.

P.248: Characteristics and outcomes of living donor kidney transplant recipients at King Faisal Hospital Rwanda.

265.2: Assessing the potency of autologous MSCs by correlating serum IDO levels and regulatory T cell in living-donor kidney transplant recipients.

265.2: Assessing the potency of autologous MSCs by correlating serum IDO levels and regulatory T cell in living-donor kidney transplant recipients.

Kidney Transplant Outcomes in Amyloidosis: US National Database Study.

We aimed to assess contemporary transplant outcomes among kidney recipients with amyloidosis, as the treatment and prognosis of amyloidosis have shown improvement over time. Using the US Organ Procurement and Transplantation Network database, we initially evaluated the changes in patient and graft survival among kidney recipients with amyloidosis from 2002 to 2021. We then compared transplant outcomes between recipients with amyloidosis versus those with diabetic and nondiabetic causes of kidney failure, creating 1:4 matches with highly similar characteristics separately for deceased donor kidney transplant (DDKT) and living donor kidney transplant (LDKT) during the last decade (2012-2021). We identified 643 kidney recipients with amyloidosis during 2002-2021. Patient and death-censored graft survival improved over time. In the matching analysis for 207 DDKT and 166 LDKT recipients with amyloidosis during 2012-2021, patient survival was not significantly different between amyloidosis and diabetes groups in both DDKT (log-rank, P = 0.057) and LDKT (P = 0.99). Compared with the nondiabetes group, patient survival in the amyloidosis group was not significantly different for DDKTs (P = 0.56) but was significantly lower for LDKTs (P = 0.04). Death-censored graft failure risk was not significantly different between amyloidosis and diabetes or nondiabetes groups for both DDKTs (P = 0.78 and 0.75) and LDKTs (P = 0.40 and 0.24). In this well-matched cohort study, we found no significant differences in patient and graft survival between kidney recipients with amyloidosis and those with diabetes. Similarly, these outcomes were not significantly different between those with amyloidosis versus nondiabetic causes, except for patient survival of LDKT recipients.

Robot-assisted kidney transplantation: a propensity score-matched cohort analysis of early experience.

Kidney transplantation is the preferred treatment for patients with end-stage kidney disease. Since the introduction of robot-assisted kidney transplantation (RAKT), several centers have applied this technique as an alternative to open kidney transplantation (OKT). The objective of this study is to analyze our early experience, focusing on surgical technique and learning curve, and postoperative outcomes of RAKT. We retrospectively reviewed 782 living donor kidney transplantation recipients between January 2018 and January 2024. A propensity score-matched cohort of 50 RAKT and 150 OKT patients was evaluated for intraoperative and postoperative variables. Shewhart control charts and CUSUM analysis were used to evaluate technical outcomes and learning curves of RAKT. Postoperative eGFR values, complications, and biopsy results were compared for overall graft function and safety. RAKT patients were associated with significantly longer overall operative, rewarming, and anastomosis times. Although overall postoperative eGFR trends showed comparable graft function between RAKT and OKT recipients (51.35±2.64 vs. 54.01±1.45; P=0.315), RAKT patients with extremely long rewarming times exhibited aggravated chronic scores at 1 year protocol biopsies (Δ Chronicity Index = 4.45±1.92, P<0.001). CUSUM analysis of rewarming time revealed that proficiency in RAKT is achieved after approximately 15 cases. Despite longer anastomosis and ischemic times, even during the early stages of RAKT adoption, the RAKT group did not differ significantly in graft function or postoperative complications from the OKT group.

The Prevalence and Outcomes of BK Polyoma Virus Nephropathy in Living Donor Kidney Transplant Recipients

The Prevalence and Outcomes of BK Polyoma Virus Nephropathy in Living Donor Kidney Transplant Recipients

Prognostic role of nutritional and inflammatory indicators for patient survival and death with functional graft in living kidney transplant recipients.

The clinical importance of nutrition and inflammation in patients with end-stage renal disease is well established. In this study, we investigated the role of nutritional and inflammatory indicators in the patient outcomes of living donor kidney transplant recipients. We included 204 consecutive patients who underwent kidney transplantation at our institute between 2003 and 2022. We retrospectively reviewed medical charts to obtain clinical information. Six nutritional indicators and two inflammatory indicators were assessed. Patient outcomes were investigated, and predictive factors were explored. The median patient age and follow-up period were 48years and 99months, respectively. The cohort included patients with preoperative malnutrition and microinflammation. No significant differences in graft survival were identified according to nutritional and inflammatory indicators, whereas the survival index, controlled nutritional status, and C-reactive protein levels were associated with patient survival. The survival index was an independent indicator of survival and death in patients with functioning grafts (P = 0.047 and P = 0.013, respectively). Furthermore, the C-reactive protein level could distinguish between low and high mortality risks in patients with good nutrition (P = 0.019). Our findings suggest that nutrition and inflammation indicators play important roles in predicting outcomes in living donor kidney transplantation recipients. Further research is warranted to establish optimal management strategies.

Impact of Norepinephrine and Dopamine Infusion on Renal Arterial Resistive Index during Pre-Emptive Living Donor Kidney Transplantation: Propensity Score Matching Analysis.

Background: Living donor kidney transplantation (LDKT) is a crucial treatment for end-stage renal disease, with pre-emptive LDKT (transplantation before dialysis initiation) offering significant benefits in graft function and patient survival. The selection of a vasopressor during LDKT, particularly between norepinephrine and dopamine, and its impact on renal arterial hemodynamics measured using the renal arterial resistive index (RARI) is poorly understood. Methods: This retrospective observational cohort study enrolled 347 eligible pre-emptive LDKT recipients from the Seoul St. Mary's Hospital between January 2019 and June 2023. Utilizing propensity score matching (PSM), the patients were categorized into dopamine and norepinephrine groups to compare the effects of these vasopressors on the intraoperative RARI, postoperative estimated glomerular filtration rate (eGFR), and hourly urine output. The RARI was measured via the Doppler ultrasonography of the renal hilum and parenchyma post-graft vascular and ureteral anastomoses. Results: The preoperative differences in the recipients' and donors' characteristics were mitigated following PSM. The dopamine group exhibited higher intraoperative RARI values at the renal hilum (0.77 ± 0.11 vs. 0.66 ± 0.13, p < 0.001) and parenchyma (0.71 ± 0.1 vs. 0.6 ± 0.1, p < 0.001) compared to those of the norepinephrine group. However, these differences were not statistically significant on postoperative day 7. The norepinephrine infusion adjusted for the propensity scores was associated with significantly lower odds of an RARI > 0.8 (hilum: OR = 0.214, 95% CI = 0.12-0.382, p < 0.001; parenchyma: OR = 0.1, 95% CI = 0.029-0.348, p < 0.001). The early postoperative outcomes showed a higher eGFR (day 1: 30.0 ± 13.3 vs. 25.1 ± 17.4 mL/min/1.73 m2, p = 0.004) and hourly urine output (day 1: 41.8 ± 16.9 vs. 36.5 ± 14.4 mL/kg/h, p = 0.002) in the norepinephrine group. Furthermore, the long-term outcomes were comparable between the groups. Conclusions: Norepinephrine infusion during pre-emptive LDKT is associated with more favorable intraoperative renal arterial hemodynamics, as evidenced by a lower RARI and improved early postoperative renal function compared to those of dopamine. These findings suggest a potential preferential role for norepinephrine in optimizing perioperative management and early graft functions in LDKT recipients. Given the retrospective nature of this study, further prospective studies are needed to confirm these observations. Additionally, the study limitations include the potential for unmeasured confounding factors and the inability to determine causality due to its observational design.

Late Treatment With Autologous Expanded Regulatory T-cell Therapy After Alemtuzumab Induction Is Safe and Facilitates Immunosuppression Minimization in Living Donor Renal Transplantation.

The TWO Study (Transplantation Without Overimmunosuppression) aimed to investigate a novel approach to regulatory T-cell (Treg) therapy in renal transplant patients, using a delayed infusion protocol at 6 mo posttransplant to promote a Treg-skewed lymphocyte repopulation after alemtuzumab induction. We hypothesized that this would allow safe weaning of immunosuppression to tacrolimus alone. The COVID-19 pandemic led to the suspension of alemtuzumab use, and therefore, we report the unique cohort of 7 patients who underwent the original randomized controlled trial protocol. This study presents a unique insight into Treg therapy combined with alemtuzumab and is therefore an important proof of concept for studies in other diseases that are considering lymphodepletion. Living donor kidney transplant recipients were randomized to receive autologous polyclonal Treg at week 26 posttransplantation, coupled with weaning doses of tacrolimus, (Treg therapy arm) or standard immunosuppression alone (tacrolimus and mycophenolate mofetil). Primary outcomes were patient survival and rejection-free survival. Successful cell manufacturing and cryopreservation until the 6-mo infusion were achieved. Patient and transplant survival was 100%. Acute rejection-free survival was 100% in the Treg-treated group at 18 mo after transplantation. Although alemtuzumab caused a profound depletion of all lymphocytes, including Treg, after cell therapy infusion, there was a transient increase in peripheral Treg numbers. The study establishes that delayed autologous Treg therapy is both feasible and safe, even 12 mo after cell production. The findings present a new treatment protocol for Treg therapy, potentially expanding its applications to other indications.

#2207 CD3(+) T cell depletion does not predict short term outcomes in kidney transplant patients

Abstract Background and Aims Anti-thymocyte globulin (ATG) is the most frequently agent used for immunosuppression induction therapy after kidney transplantation. The efficacy of the ATG treatment is monitored by peripheral blood CD3(+) T cell counts. ATG dosing can be tailored to reach and keep the target commonly accepted as below 50/μL within the week of transplant. In this study, we investigated the significance of reaching CD3(+) T cell target regarding short term adverse outcomes of biopsy-proved rejection, BK viremia and infection related hospitalization in living donor kidney transplant recipients. Method This retrospective observational study was conducted on adult patients who received living donor kidney transplants from January 1, 2015 to October 1, 2022. Demographic, clinical and laboratory information were collected using electronical medical records. The average CD3(+) T cell counts of postoperative first 3 days were calculated. Patients with CD3(+) T cell counts ≤ 50/μL were classified as “Optimally Treated”, while the patients with CD3(+) T cell counts &amp;gt;50/μL were classified as “Suboptimally Treated”. The incidence of biopsy-proven rejection, BK viremia and infection related hospitalization in 6 months following the transplant surgery were compared in these two groups. Results Sixty one patients were included in the study. Twenty eight were women and the average age was 39 ± 12.7 years. Average HLA mismatch count was 3.6 ± 1.7. Ten patients were desensitized before kidney transplant. Average ATG dose was 6.8 ± 2.3 mg/kg. Mean average CD3(+) T cell count of postoperative first 3 days were 93.9 ± 87.8/μL. During 6 months of follow up, 34.4% (n = 21) had at least one biopsy proved rejection episode, 21.3% (n = 13) had at least one infection related hospitalization and 11.4% (n = 7) had BK viremia. According to average CD3(+) T cell counts of postoperative first 3 days, 16 patients were in “Optimally Treated” group, whereas 45 patients were in “Suboptimally Treated” group. The patients in both groups had similar mean age, gender distribution, HLA mismatch, pretransplant desensitization status and total ATG doses. In 6 months of follow-up, the patients in “Optimally Treated” and “Suboptimally Treated” groups had no statistically difference in incidence of biopsy-proved rejection, BK viremia and infection related hospitalization. Conclusion In our study, we could not find any evidence to confirm the significance of reaching CD3(+) T cell target of 50/μL in first 3 days after transplant surgery regarding short term adverse outcomes of biopsy-proved rejection, BK viremia and infection related hospitalization. The value of CD3(+) T cell monitoring to adjust ATG therapy after kidney transplant surgery is questionable. Thus, in the light of our findings, we do not support the use of CD3(+) T cell counts in optimization of induction therapy with ATG after renal transplantation.

#3045 Understanding BK polyomavirus: surveillance and clearance in kidney transplant recipients

Abstract Background and Aims BK virus allograft nephropathy (BKVN) can develop graft loss. The aim of this study was to describe BK viraemia and BKVN related factors, our experience in treatment and the impact in graft survival. Method We introduce a retrospective cohort of 78 kidney transplant recipients (KTRs) with BKV viraemia between January 2013 from January 2020 and with follow-up until December 31, 2022 in our center. Results Thirty-four (43%) were living donor KTRs, 30 (38.5%) DBD, 11 (14.1%) DCD III, and 2 (4.3%) DCD II. Twenty-seven (34.6%) of recipients were sensitized. Immunosuppressive induction was based on Anti-CD25 in 33 (42.3%), and antilymphocytes antibodies in 44 (56.4%). Basal treatment was TAC+MPA+PDN in 44 (56.4%) and TAC+iMTOR+PDN in 31 (39.7%). Median FK levels were 7.9 (ng/ml) in the first replication. Median BK load at first replication was 3636 [1030-97151]cp/ml. Median time to replication from transplant was 6 months, and from highest load 9 months. Immunosuppression adjustment after replication was switch to imTOR+FK 25 (32.1%), low FK 17 (21.8%), imTOR 4 (5.1%). Only surveillance was chosen in 27 (35.9%). Others therapies were Leflunomide 4 (5.1%), IVIG 6 (7.7%) or both 3 (3.8%). Photopheresis was used in 2 cases. Viraemia was cleared in 17/24 (70.8%) of the cases in which conversion to mTOR was performed as an immunosuppression adjustment strategy, versus 9 (56.3%) in which it was decided to lower FK and in 3 (75%) with low MMF. Ten cases in which surveillance was carried out became negative for viremia, possibly because they were patients with a lower replicative load. BKN occurred in 28/78 (36%) cases, interstitial fibrosis (ci&amp;gt;2) was found in 14/28 (48.27%). Graft rejection after BKN was developed in 11/28 (37.9%). Graft loss occurred in 26/78 (33.3%) of cohort and in 19 (65%)of patients with BKN, reaching a significant value. Viraemia clearance was reached in 41 (60.3%) in mean time of 10 months [4-27]. Mean time since BKVN until graft loss was 22.3 months [10.2-34.2]. Exitus occurred in 7/78 (9%) of replication cases and in 3/28 (10.7%)of BKN patients. Maximum BK load Exp β; [1-1], p 0.033, first replication load &amp;gt;10.000 (cp/ml) and deceased donor status (Exp β; 6,9 [2.43-19.57] and 2.98 [1.10-8.07] p 0.031, were related to BKVN in bivariate analysis. No significant differences were found between therapy in BKVN and graft loss, maybe due to low BKVN cases. Conclusion In our cohort, maximum BK load, first replication load &amp;gt;10,000 (cp/ml), and deceased donor status appear to be related to nephropathy. No significant differences were found between induction, basal or adjuvant therapy and graft loss. The current challenge is to stop replication before fibrosis, without increasing the risk of rejection.

An ethical analysis of conditional and partially directed live kidney donation among strangers—The Israeli experience

Living donor kidney transplantation (LDKT) is one of the most effective treatment options for people with end-stage renal disease. Traditionally, LDKT can be either “directed” or “nondirected,” based on whether the recipient is specified by the donor. Recently, there has been an increase in conditional and semidirected live kidney donation among strangers, where the donor specifies the characteristics of the recipient whom they wish to donate to. This practice has both gained popularity and sparked controversy in the state of Israel through the nonprofit organization Matnat Chaim. We analyze the ethical implications of this practice by applying traditional principles of medical ethics to conditional LDKT. Although semidirected and conditional LDKT presents some ethical challenges, overall, its practice effectively aligns with core ethical principles. The donors' right to make stipulations respects the donor’s autonomy, the practice avoids harm and benefits both donor and recipient, and justice and utility are upheld as the practice specifically benefits marginalized patients and optimizes resource utilization. Finally, we present data from our institution demonstrating how conditional LDKT increased transplantation for all ethnic groups; Jewish recipients of LDKT increased by 151.32% (P = .034) Arab recipients of LDKT increased by 111.11% (P = .036).

Effects of Antithymocyte Globulin, Basiliximab, and Induction-Free Treatment in Living Donor Kidney Transplant Recipients on Tacrolimus-Based Immunosuppression.

Induction treatment in renal transplant is associated with better graft survival. However, intensified immunosuppression is known to cause unwanted side effects such as infection and malignancy. Furthermore, the effects of the routine use of immunosuppressants in low-risk kidney transplant recipients are still not clear. In this study, we assessed the first-year safety and efficacy of induction treatment. We examined first living donor kidney transplant patients who were on tacrolimus based immunosuppression therapy. We formed 3 groups according to the induction status: antithymocyte globulin induction, basiliximab induction, and no induction. We collected outcome data on delayed graft function, graft loss, creatinine levels, estimated glomerular filtration rates, acute rejection episodes, hospitalization episodes, and infection episodes, including cytomegalovirus infection and bacterial infections. We examined a total of 126 patients (age 35 ± 12 years; 65% male). Of them, 25 received antithymocyte globulin, 52 received basiliximab, and 49 did notreceive any induction treatment. We did not observe any statistically significant difference among the 3 groups in terms of acute rejection episodes, delayed graft function, and first-year graft loss. The estimated glomerular filtration rates were similar among the groups. Overall bacterial infectious complications and cytomegalovirus infection showed similar prevalence among all groups. Hospitalization was less common in the induction-free group. In low-risk patients, induction-free regimens could be associated with a better safety profile without compromising graft survival. Therefore, induction treatment may be disregarded in first living donor transplant patients who receive tacrolimusbased triple immunosuppression treatment.

Nocardiosis in kidney transplant recipients: A tertiary care center experience

IntroductionKidney transplant recipients are at increased risk of opportunistic infections, including Nocardia. The incidence of nocardiosis in kidney transplant recipients is 0.4–1.3%. The data regarding its epidemiology and outcomes is limited. MethodsThis was a 10-year retrospective observational study from January 2012 to December 2021 at a tertiary care center in northern India, in which all kidney transplant recipients with Nocardia infection were included and followed. Results12 (1.1%) patients had a Nocardia infection among the 1108 kidney transplant recipients. All were living donor kidney transplant recipients, and the mean age at diagnosis was 48.67 ± 12.60 years. Nocardia infection occurred at a median of 26 months (range 4–235) post-transplantation, with 4 (33.1%) of the cases occurring within a year of transplant. Breakthrough infection occurred in 7 (58.3%) patients on cotrimoxazole prophylaxis. 41.7% (n = 5) cases had an episode of rejection in the preceding year of Nocardia diagnosis. Concurrent cytomegalovirus (CMV) infection was present in one (8.3%) case. The lung was the most frequently involved organ. Microscopy was positive in all the cases; while culture was positive in 10 cases, and antimicrobial susceptibility testing (AST) were performed for these isolates. The majority (60%) of isolates were resistant to cotrimoxazole. All tested isolates remained susceptible to Amikacin, Imipenem, and Linezolid. No patients experienced Nocardia recurrence after completion of antibiotic therapy. The mortality at 12 months was 66.7% (n = 4), and only one death was Nocardia-related. ConclusionNocardia may cause a late-manifesting infection beyond the traditional window. The cotrimoxazole prophylaxis may not be sufficient for Nocardia prevention.

Immunosuppression withdrawal in living-donor renal transplant recipients following induction with antithymocyte globulin and rituximab: Results of a prospective clinical trial

Durable tolerance in kidney transplant recipients remains an important but elusive goal. We hypothesized that adding B cell depletion to T cell depletion would generate an immune milieu postreconstitution dominated by immature transitional B cells, favoring tolerance. The Immune Tolerance Network ITN039ST Research Study of ATG and Rituximab in Renal Transplantation was a prospective multicenter pilot study of live donor kidney transplant recipients who received induction with rabbit antithymocyte globulin and rituximab and initiated immunosuppression (IS) withdrawal (ISW) at 26 weeks. The primary endpoint was freedom from rejection at 52 weeks post-ISW. Six of the 10 subjects successfully completed ISW. Of these 6 subjects, 4 restarted immunosuppressive medications due to acute rejection or recurrent disease, 1 remains IS-free for over 9 years, and 1 was lost to follow-up after being IS-free for 42 weeks. There were no cases of patient or graft loss. CD19+ B cell frequencies returned to predepletion levels by 26 weeks posttransplant; immunoglobulin D+CD27--naïve B cells predominated. In contrast, memory cells dominated the repopulation of the T cell compartment. A regimen of combined B and T cell depletion did not generate the tolerogenic B cell profile observed in preclinical studies and did not lead to durable tolerance in the majority of kidney transplant recipients.