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BK Polyomavirus in Pediatric Renal Transplantation-What We Know and What We Do Not. Biomedicines 2024; 12:1093. [PMID: 38791055 PMCID: PMC11118040 DOI: 10.3390/biomedicines12051093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 05/08/2024] [Accepted: 05/13/2024] [Indexed: 05/26/2024] Open
Abstract
BK polyomavirus (BKPyV) is still a real threat in the management of kidney transplantation. Immunosuppressive treatment disrupts the equilibrium between virus replication and immune response, and uncontrolled BKPyV replication leads to nephropathy (BKPyV nephropathy). The first evidence of BKPyV reactivation in transplant recipients is the detection of viral shedding in urine, which appears in 20% to 60% of patients, followed by BKPyV viremia in 10-20% of kidney transplant recipients. BKPyV nephropathy eventually occurs in 1-10% of this population, mainly within the first 2 years post-transplantation, causing graft loss in about half of those patients. Few data exist regarding the pediatric population and we focus on them. In this paper, we review the existing diagnostic methods and summarize the evidence on the role of BKPyV humoral and cellular immunity in modulating the clinical course of BKPyV infection and as potential predictors of the outcome. We look at the known risk factors for BKPyV nephropathy in the immunosuppressed patient. Finally, we propose a sensible clinical attitude in order to screen and manage BKPyV infection in kidney transplant children.
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In Vitro Profiling of Commonly Used Post-transplant Immunosuppressants Reveals Distinct Impact on Antiviral T-cell Immunity Towards CMV. Transpl Int 2024; 37:12720. [PMID: 38655204 PMCID: PMC11035762 DOI: 10.3389/ti.2024.12720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/27/2024] [Indexed: 04/26/2024]
Abstract
Infectious complications, including widespread human cytomegalovirus (CMV) disease, frequently occur after hematopoietic stem cell and solid organ transplantation due to immunosuppressive treatment causing impairment of T-cell immunity. Therefore, in-depth analysis of the impact of immunosuppressants on antiviral T cells is needed. We analyzed the impact of mTOR inhibitors sirolimus (SIR/S) and everolimus (EVR/E), calcineurin inhibitor tacrolimus (TAC/T), purine synthesis inhibitor mycophenolic acid (MPA/M), glucocorticoid prednisolone (PRE/P) and common double (T+S/E/M/P) and triple (T+S/E/M+P) combinations on antiviral T-cell functionality. T-cell activation and effector molecule production upon antigenic stimulation was impaired in presence of T+P and triple combinations. SIR, EVR and MPA exclusively inhibited T-cell proliferation, TAC inhibited activation and cytokine production and PRE inhibited various aspects of T-cell functionality including cytotoxicity. This was reflected in an in vitro infection model, where elimination of CMV-infected human fibroblasts by CMV-specific T cells was reduced in presence of PRE and all triple combinations. CMV-specific memory T cells were inhibited by TAC and PRE, which was also reflected with double (T+P) and triple combinations. EBV- and SARS-CoV-2-specific T cells were similarly affected. These results highlight the need to optimize immune monitoring to identify patients who may benefit from individually tailored immunosuppression.
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Cellular Immunobiology and Molecular Mechanisms in Alloimmunity-Pathways of Immunosuppression. Transplantation 2024; 108:148-160. [PMID: 37309030 DOI: 10.1097/tp.0000000000004646] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Current maintenance immunosuppression commonly comprises a synergistic combination of tacrolimus as calcineurin inhibitor (CNI), mycophenolic acid, and glucocorticoids. Therapy is often individualized by steroid withdrawal or addition of belatacept or inhibitors of the mechanistic target of rapamycin. This review provides a comprehensive overview of their mode of action, focusing on the cellular immune system. The main pharmacological action of CNIs is suppression of the interleukin-2 pathway that leads to inhibition of T cell activation. Mycophenolic acid inhibits the purine pathway and subsequently diminishes T and B cell proliferation but also exerts a variety of effects on almost all immune cells, including inhibition of plasma cell activity. Glucocorticoids exert complex regulation via genomic and nongenomic mechanisms, acting mainly by downregulating proinflammatory cytokine signatures and cell signaling. Belatacept is potent in inhibiting B/T cell interaction, preventing formation of antibodies; however, it lacks the potency of CNIs in preventing T cell-mediated rejections. Mechanistic target of rapamycin inhibitors have strong antiproliferative activity on all cell types interfering with multiple metabolic pathways, partly explaining poor tolerability, whereas their superior effector T cell function might explain their benefits in the case of viral infections. Over the past decades, clinical and experimental studies provided a good overview on the underlying mechanisms of immunosuppressants. However, more data are needed to delineate the interaction between innate and adaptive immunity to better achieve tolerance and control of rejection. A better and more comprehensive understanding of the mechanistic reasons for failure of immunosuppressants, including individual risk/benefit assessments, may permit improved patient stratification.
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mTOR inhibitors in a patient with lupus nephritis; why not? Nefrologia 2023; 43 Suppl 2:101-103. [PMID: 36564228 DOI: 10.1016/j.nefroe.2022.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 03/03/2022] [Indexed: 06/17/2023] Open
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Difficult-to-Treat Rejections in Kidney Transplant Recipients: Our Experience with Everolimus-Based Quadruple Maintenance Therapy. J Clin Med 2023; 12:6667. [PMID: 37892805 PMCID: PMC10607360 DOI: 10.3390/jcm12206667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 10/15/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023] Open
Abstract
All chronic and treatment-resistant acute rejections are "difficult-to-treat" and lead to progressive loss of graft function in kidney transplant recipients (KTR), as no effective treatment exists for such rejections to date. We review our experience with a novel strategy to treat such rejections by adding everolimus as a "rescue" to conventional triple maintenance therapy with prednisolone, mycophenolate mofetil and calcineurin inhibitor. We retrospectively analysed data in 28 KTR who received everolimus-based quadruple therapy at our institution for biopsy-proven chronic active T cell-mediated or antibody-mediated rejection (n = 19) or treatment-resistant acute rejections (n = 9) between 2011-2017. The primary outcome was 5-year death-censored graft survival. Main secondary outcomes were response to treatment defined by stable or improved graft function, 5-year patient survival and discontinuation rate of treatment. The Kaplan-Meier estimate for 5-year death-censored graft survival was 79% in all patients, 90% for patients with chronic active T cell-mediated rejections, 78% for chronic active antibody-mediated rejection and 67% for acute rejections. Response to treatment was achieved in 43% and 5-year patient survival was 94%. Treatment was stopped in 12 (43%) patients due to adverse events. Everolimus-based maintenance quadruple therapy, despite high rate of everolimus discontinuation due to adverse events, may be a valid approach in a subset of kidney transplant recipients with such difficult-to-treat rejections, which otherwise would lead to a high rate of graft loss.
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A comprehensive update of the metabolic and toxicological considerations for immunosuppressive drugs used during pancreas transplantation. Expert Opin Drug Metab Toxicol 2023; 19:405-427. [PMID: 37542452 DOI: 10.1080/17425255.2023.2243808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 07/24/2023] [Accepted: 07/28/2023] [Indexed: 08/07/2023]
Abstract
INTRODUCTION Despite significant advancements in immunosuppressive regimens and surgical techniques, the prevalence of adverse events related to immunosuppression remains a major challenge affecting the long-term survival rates of pancreas and kidney allografts. AREAS COVERED This article presents a comprehensive review of the literature and knowledge (Jan/2012-Feb/2023) concerning glucose metabolism disorders and nephrotoxicity associated with tacrolimus and mammalian target of rapamycin inhibitors (mTORi). Novel signaling pathways potentially implicated in these adverse events are discussed. Furthermore, we extensively examine the findings from clinical trials evaluating the efficacy and safety of tacrolimus, mTORi, and steroid minimization. EXPERT OPINION Tacrolimus-based regimens continue to be the standard treatment following pancreas transplants. However, prolonged use of tacrolimus and mTORi may lead to hyperglycemia and nephrotoxicity. Understanding and interpreting experimental data, particularly concerning novel signaling pathways beyond calcineurin-NFAT and mTOR pathways, can offer valuable insights for therapeutic interventions to mitigate hyperglycemia and nephrotoxicity. Additionally, critically analyzing clinical trial results can identify opportunities for personalized safety-based approaches to minimize side effects. It is imperative to conduct randomized-controlled studies to assess the impact of mTORi use and steroid-free protocols on pancreatic allograft survival. Such studies will aid in tailoring treatment strategies for improved transplant outcomes.
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Single-Cell, High-Content Microscopy Analysis of BK Polyomavirus Infection. Microbiol Spectr 2023; 11:e0087323. [PMID: 37154756 PMCID: PMC10269497 DOI: 10.1128/spectrum.00873-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 04/08/2023] [Indexed: 05/10/2023] Open
Abstract
By adulthood, the majority of the population is persistently infected with BK polyomavirus (BKPyV). Only a subset of the population, generally transplant recipients on immunosuppressive drugs, will experience disease from BKPyV, but those who do have few treatment options and, frequently, poor outcomes, because to date there are no effective antivirals to treat or approved vaccines to prevent BKPyV. Most studies of BKPyV have been performed on bulk populations of cells, and the dynamics of infection at single-cell resolution have not been explored. As a result, much of our knowledge is based upon the assumption that all cells within a greater population are behaving the same way with respect to infection. The present study examines BKPyV infection on a single-cell level using high-content microscopy to measure and analyze the viral protein large T antigen (TAg), promyelocytic leukemia protein (PML), DNA, and nuclear morphological features. We observed significant heterogeneity among infected cells, within and across time points. We found that the levels of TAg within individual cells did not necessarily increase with time and that cells with the same TAg levels varied in other ways. Overall, high-content, single-cell microscopy is a novel approach to studying BKPyV that enables experimental insight into the heterogenous nature of the infection. IMPORTANCE BK polyomavirus (BKPyV) is a human pathogen that infects nearly everyone by adulthood and persists throughout a person's life. Only people with significant immune suppression develop disease from the virus, however. Until recently the only practical means of studying many viral infections was to infect a group of cells in the laboratory and measure the outcomes in that group. However, interpreting these bulk population experiments requires the assumption that infection influences all cells within a group similarly. This assumption has not held for multiple viruses tested so far. Our study establishes a novel single-cell microscopy assay for BKPyV infection. Using this assay, we discovered differences among individual infected cells that have not been apparent in bulk population studies. The knowledge gained in this study and the potential for future use demonstrate the power of this assay as a tool for understanding the biology of BKPyV.
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Infections after organ transplantation and immune response. Transpl Immunol 2023; 77:101798. [PMID: 36731780 DOI: 10.1016/j.trim.2023.101798] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 01/08/2023] [Accepted: 01/26/2023] [Indexed: 01/31/2023]
Abstract
Organ transplantation has provided another chance of survival for end-stage organ failure patients. Yet, transplant rejection is still a main challenging factor. Immunosuppressive drugs have been used to avoid rejection and suppress the immune response against allografts. Thus, immunosuppressants increase the risk of infection in immunocompromised organ transplant recipients. The infection risk reflects the relationship between the nature and severity of immunosuppression and infectious diseases. Furthermore, immunosuppressants show an immunological impact on the genetics of innate and adaptive immune responses. This effect usually reactivates the post-transplant infection in the donor and recipient tissues since T-cell activation has a substantial role in allograft rejection. Meanwhile, different infections have been found to activate the T-cells into CD4+ helper T-cell subset and CD8+ cytotoxic T-lymphocyte that affect the infection and the allograft. Therefore, the best management and preventive strategies of immunosuppression, antimicrobial prophylaxis, and intensive medical care are required for successful organ transplantation. This review addresses the activation of immune responses against different infections in immunocompromised individuals after organ transplantation.
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Characteristics, risk factors and outcome of BKV nephropathy in kidney transplant recipients: a case-control study. BMC Infect Dis 2023; 23:74. [PMID: 36747162 PMCID: PMC9903532 DOI: 10.1186/s12879-023-08043-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 01/30/2023] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Following kidney transplantation, BK virus associated nephropathy (BKVN) occurs in 1 to 10% of kidney transplant recipients (KTR) and represents a major cause of graft loss. We aim at identifying factors associated with biopsy proven BKVN among KTR. METHODS We conducted a retrospective case-control study including all KTR with a biopsy-proven diagnosis of BKVN between 2005 and 2019. Clinical characteristics and outcome were described. For each case, one control KTR without BKV infection was identified and matched by age, transplant date, and donor status. Factors associated with BKVN diagnosis were identified using exact conditional logistic regression. Comparative survival was described using Kaplan-Meier estimator. RESULTS Sixty-four cases of BKVN were identified among 1737 new kidney transplantation (3.7% prevalence). Clinical characteristics did not differ between groups, except for a higher c-PRA among cases. BKVN occurred in a median time of 11 (5-14.5) months after KT, and was associated with a significantly impaired graft function at diagnosis. Following BKVN, 61 (95%) of the patients had immunosuppression reduction, which led to BKV DNAemia resolution in 49% of cases. In multivariate analysis, factors associated with BKVN diagnosis were lymphopenia < 500/mm3 and a prednisone dose > 7.5 mg/day. Median duration of follow-up was 40 months for both groups. BKVN was associated with a significantly increased risk of graft rejection (P = 0.02) and return to dialysis (P = 0.01). CONCLUSIONS BKVN remains a severe complication in KTR and is associated with an increased risk for acute rejection and return to dialysis. Lymphopenia below 500/mm3 and corticosteroid maintenance therapy are significantly associated with biopsy-proven BKVN diagnosis.
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Conversion to mTOR-Inhibitors Plus IV Immunoglobulins in Kidney-Transplant Recipients with BKV Infection: A Retrospective Comparative Study. J Clin Med 2022; 11:jcm11247292. [PMID: 36555909 PMCID: PMC9785214 DOI: 10.3390/jcm11247292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/02/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022] Open
Abstract
BK virus-associated nephropathy (PvAN) increases the risk of graft failure justifying treatment. Conversion to mammalian target of rapamycin inhibitors (mTORi) and Human polyclonal immunoglobulins (IVIg) could prevent the risk of PvAN. Our retrospective study assessed the efficacy of mTORi associated with IVIg therapy (mTORi±IVIg group) versus standard immunosuppression reduction to clear BKV DNAemia. Among forty-three kidney-transplanted patients with positive BKV DNAemia, we included twenty-six patients in the mTORi±IVIg group and reduced immunosuppression therapy for seventeen patients. We focused on BKV DNAemia clearance on the first-year. Renal function, rejection rate, evolution to PvAN, and complications of immunosuppression were assessed. BKV DNAemia decreased faster and significantly in the control group as compared to the mTORi±IVIg group (p < 0.001). Viral clearance was significantly higher in the control group compared to the mTORi±IVIg group (88% vs. 58%; p = 0.033). Death-censored graft loss, rejection rates and kidney-graft function at 12 months did not significantly differ. Multivariate analyses significantly associated BKV DNAemia clearance with reducing immunosuppression (OR = 0.11 (0.06−0.9), p = 0.045), female kidney donor (OR = 0.10 (0.01−0.59/)], p = 0.018) and time to first DNAemia, (OR = 0.88 (0.76−0.96), p = 0.019). In our study, the standard treatment for BKV DNAemia had better outcomes than an mTORi±IVIg conversion.
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Belatacept-Based Maintenance Immunosuppression Controls the Post-Transplant Humoral Immune Response in Highly Sensitized Nonhuman Primates. KIDNEY360 2022; 3:2116-2130. [PMID: 36591367 PMCID: PMC9802566 DOI: 10.34067/kid.0001732022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 09/12/2022] [Indexed: 11/06/2022]
Abstract
Preexisting donor-specific antibodies (DSA) to MHC antigens increase the risk of antibody-mediated rejection (AMR) in sensitized transplant recipients and reduces graft survival. Pretransplant desensitization with costimulation blockade and proteasome inhibition has facilitated transplantation in our preclinical nonhuman primate (NHP) model. However, long-term graft survival is limited by rebound of DSA after transplantation. In this study, we performed kidney transplants between highly sensitized, maximally MHC-mismatched NHPs (n=14). At kidney transplantation, primates received T cell depletion with rhesus-specific anti-thymocyte globulin (rhATG; n=10) or monoclonal anti-CD4 and anti-CD8 antibodies (n=4). Maintenance immunosuppression consisted of belatacept and tacrolimus (n=5) or belatacept and rapamycin (n=9) with steroids. Rebound of DSA post-kidney transplantation was significantly reduced compared with maintenance immunosuppression with tacrolimus, mycophenolate, and steroids. Protocol lymph node biopsy specimens showed a decrease in germinal center activity, with low frequencies of T follicular helper cells and class-switched B cells after kidney transplantation. Combined belatacept and rapamycin was superior in controlling viral reactivation, enabling weaning of ganciclovir prophylaxis. Tacrolimus was associated with increased morbidity that included cytomegalovirus and parvovirus viremia and post-transplant lymphoproliferative disorder. All primates in the tacrolimus/belatacept group failed discontinuation of antiviral therapy. Overall, belatacept-based immunosuppression increased AMR-free graft survival by controlling post-transplant humoral responses in highly sensitized NHP recipients and should be further investigated in a human clinical trial.
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CC Genotype of GNAS c.393C>T (rs7121) Polymorphism Has a Protective Effect against Development of BK Viremia and BKV-Associated Nephropathy after Renal Transplant. Pathogens 2022; 11:pathogens11101138. [PMID: 36297195 PMCID: PMC9609707 DOI: 10.3390/pathogens11101138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/23/2022] [Accepted: 09/28/2022] [Indexed: 11/07/2022] Open
Abstract
The GNAS gene encodes the alpha-subunit of the stimulatory G-protein (Gαs) in humans and mice. The single-nucleotide polymorphism of GNAS, c.393C>T, is associated with an elevated production of Gαs and an increased formation of cyclic adenosine monophosphate (cAMP). In the present study, we analyzed the effect of this GNAS polymorphism on a renal allograft outcome. We screened a cohort of 436 renal allograft recipients, who were retrospectively followed up for up to 5 years after transplant. GNAS genotypes were determined with polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) assays. The 393T allele was detected in 319 (73%) recipients (113 recipients with TT and 206 with CT genotype) and the CC genotype in 117 (27%). The CC genotype was associated with a significantly lower frequency of BK viremia (CC, 17 recipients (15%); T 84 (26%)); p = 0.01; TT, 27 vs. CC, 17, p = 0.07; TT, 27 vs. CT, 57, p = 0. 46; CT, 57 vs. CC, 17, p = 0.01) and BKV-associated nephropathy (CC, 3 recipients (3%); T, 27 (8%); p = 0.03; TT,10 vs. CC, 3, p = 0.04; TT, 10 vs. CT,17, p = 0.85; CT, 17 vs. CC,3, p = 0.04) after transplant. BKV-associated nephropathy-free survival was significantly better among CC genotype carriers than among T allele carriers (p = 0.043; TT vs. CC, p = 0.03; CT vs. CC, p = 0.04; TT vs. CT, p = 0.83). Multivariate analysis indicated an independent protective effect of the CC genotype against the development of both BK viremia (relative risk. 0.54; p = 0.04) and BKV-associated nephropathy after renal transplant (relative risk. 0.27; p = 0.036). The GNAS 393 CC genotype seems to protect renal allograft recipients against the development of BK viremia and BKV-associated nephropathy.
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Dynamic risk prediction of BK polyomavirus reactivation after renal transplantation. Front Immunol 2022; 13:971531. [PMID: 36059544 PMCID: PMC9428263 DOI: 10.3389/fimmu.2022.971531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 07/28/2022] [Indexed: 11/29/2022] Open
Abstract
Purpose To construct a dynamic prediction model for BK polyomavirus (BKV) reactivation during the early period after renal transplantation and to provide a statistical basis for the identification of and intervention for high-risk populations. Methods A retrospective study of 312 first renal allograft recipients was conducted between January 2015 and March 2022. The covariates were screened using univariable time-dependent Cox regression, and those with P<0.1 were included in the dynamic and static analyses. We constructed a prediction model for BKV reactivation from 2.5 to 8.5 months after renal transplantation using dynamic Cox regression based on the landmarking method and evaluated its performance using the area under the curve (AUC) value and Brier score. Monte-Carlo cross-validation was done to avoid overfitting. The above evaluation and validation process were repeated in the static model (Cox regression model) to compare the performance. Two patients were presented to illustrate the application of the dynamic model. Results We constructed a dynamic prediction model with 18 covariates that could predict the probability of BKV reactivation from 2.5 to 8.5 months after renal transplantation. Elder age, basiliximab combined with cyclophosphamide for immune induction, acute graft rejection, higher body mass index, estimated glomerular filtration rate, urinary protein level, urinary leukocyte level, and blood neutrophil count were positively correlated with BKV reactivation, whereas male sex, higher serum albumin level, and platelet count served as protective factors. The AUC value and Brier score of the static model were 0.64 and 0.14, respectively, whereas those of the dynamic model were 0.79 ± 0.05 and 0.08 ± 0.01, respectively. In the cross-validation, the AUC values of the static and dynamic models decreased to 0.63 and 0.70 ± 0.03, respectively, whereas the Brier score changed to 0.11 and 0.09 ± 0.01, respectively. Conclusion Dynamic Cox regression based on the landmarking method is effective in the assessment of the risk of BKV reactivation in the early period after renal transplantation and serves as a guide for clinical intervention.
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A methodologic survey on use of the GRADE approach in evidence syntheses published in high-impact factor urology and nephrology journals. BMC Med Res Methodol 2022; 22:220. [PMID: 35948868 PMCID: PMC9367121 DOI: 10.1186/s12874-022-01701-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 07/29/2022] [Indexed: 11/23/2022] Open
Abstract
Background To identify and describe the use of the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach for rating the certainty of systematic reviews (SRs) evidence published in urology and nephrology journals. Methods SRs that were published in the top ten "urology and nephrology" journals with the highest impact factor according to the 2020 Journal Citation Reports (covering 2016–2020) were systematically searched and evaluated using the GRADE approach. Results A total of 445 SRs were researched. Sixty SRs of randomized control trials (RCTs) and/or non-randomized studies (NRSs) were evaluated using the GRADE approach. Forty-nine SRs (11%) rated the outcome-specific certainty of evidence (n = 29 in 2019–2020). We identified 811 certainty of evidence outcome ratings (n = 544 RCT ratings) as follows: very low (33.0%); low (32.1%); moderate (24.5%); and high (10.4%). Very low and high certainty of evidence ratings accounted for 55.0% and 0.4% of ratings in SRs of NRSs compared to 23.0% and 15.3% in SRs of RCTs. The certainty of evidence for RCTs and NRSs was downgraded most often for risk of bias and imprecision. Conclusions We recommend increased emphasis on acceptance of the GRADE approach, as well as optimal use of the GRADE approach, in the synthesis of urinary tract evidence. Supplementary Information The online version contains supplementary material available at 10.1186/s12874-022-01701-x.
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In Vitro Study Evaluating the Effect of Different Immunosuppressive Agents on Human Polyomavirus BK Replication. Transplant Proc 2022; 54:2035-2041. [PMID: 35659782 DOI: 10.1016/j.transproceed.2022.04.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 04/08/2022] [Indexed: 01/31/2023]
Abstract
BACKGROUND Human polyomavirus BK (BKPyV) is the etiologic agent of polyomavirus-associated nephropathy, a leading cause of kidney transplant dysfunction. Because of the lack of antiviral therapies, immunosuppression minimization is the recommended treatment. This strategy offers suboptimal outcomes and entails a significant risk of rejection. Our aim was to evaluate the effect of different immunosuppressive drugs (leflunomide, tacrolimus, mycophenolic acid, sirolimus, and everolimus) and their combinations in an in vitro model of BKPyV infection. METHODS Human renal tubular epithelial cells were infected with BKPyV and treated with leflunomide, tacrolimus, mycophenolic acid, sirolimus, and everolimus, administered alone or in some combination thereof. Viral replication was assessed every 24 hours (up to 72 hours) by BKPyV-specific quantitative real-time polymerized chain reaction for the VIRAL PROTEIN 1 sequence in cell supernatants and by western blot analysis targeting the viral protein 1 and the glyceraldehyde 3-phosphate dehydrogenase on total protein lysates. Results were described as viral copies/mL and compared between treatments at any prespecified time point of the study. RESULTS The highest inhibitory effects were observed using leflunomide or everolimus plus mycophenolic acid (mean BKPyV replication log reduction 0.28). The antiviral effect of everolimus persisted when it was used in combination with tacrolimus (mean BKPyV replication log reduction 0.27). CONCLUSIONS Our experience confirms that everolimus has anti-BKPyV properties and prompts future research to investigate possible mechanisms of action. It also provides a rational basis for targeted clinical trials evaluating alternative immunosuppressive modification strategies.
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Analysis of risk factors for impaired wound healing after kidney transplantation. Int Wound J 2022; 20:140-144. [PMID: 35644604 PMCID: PMC9797925 DOI: 10.1111/iwj.13848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Revised: 05/08/2022] [Accepted: 05/09/2022] [Indexed: 01/07/2023] Open
Abstract
To analyse risk factors for impaired wound healing after kidney transplantation to guide clinical decision-making. A retrospective analysis was performed on patients who received kidney transplantation from January 1, 2019, to May 1, 2021, at Kidney Transplantation Center in Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine. A case-control study was used to identify a cohort of patients with similar baseline characteristics according to 1:4 ratio. Patients were divided into two groups according to whether there was impaired wound healing after surgery. The basic data and clinical examinations between the two groups were compared, and the risk factors for impaired wound healing after kidney transplantation were analysed using univariate and multivariate analyses. According to the data type, independent samples t-test or Chi-squared test was used for comparison between groups. Furthermore, multivariate logistic regression analysis was used to analyse different risk factors and calculate the odds ratio (OR) and 95% confidence interval (CI) of each factor. A total of 18 patients showed impaired wound healing after kidney transplantation. And we conducted 72 statically matched controls. Age, diabetes, transplant types, body mass index (BMI), albumin, haemoglobin, and wound infection were statistically different between the two groups. The factors with statistically significant differences in univariate analysis were included in multivariate logistic regression analysis. The results showed that BMI > 25, fasting blood glucose level, albumin level, and prealbumin level were independent risk factors for impaired wound healing after kidney transplantation. Risk factors for impaired wound healing after kidney transplantation can be detected after surgery. Strengthening postoperative monitoring and early intervention of recipients with such factors may effectively prevent impaired wound healing after kidney transplantation.
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Incidence of cytomegalovirus infection in seropositive kidney transplant recipients treated with everolimus: A randomized, open-label, multicenter phase 4 trial. Am J Transplant 2022; 22:1430-1441. [PMID: 34990047 DOI: 10.1111/ajt.16946] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 12/02/2021] [Accepted: 12/28/2021] [Indexed: 01/25/2023]
Abstract
Cytomegalovirus (CMV) persists as the most frequent opportunistic infection among solid organ transplant recipients. This multicenter trial aimed to test whether treatment with everolimus (EVR) could decrease the incidence of CMV DNAemia and disease. We randomized 186 CMV seropositive kidney transplant recipients in a 1:1 ratio to receive EVR or mycophenolic acid (MPA) in association with basiliximab, cyclosporin, and steroids and 87 in each group were analyzed. No universal prophylaxis was administered to either group. The composite primary endpoint was the presence of CMV DNAemia, CMV treatment, graft loss, death, and discontinuation of the study at 6 months posttransplant. In the modified intent-to-treat analysis, 42 (48.3%) and 70 (80.5%) patients in the EVR and MPA groups reached the primary endpoint (OR = 0.21, 95% CI: 0.11-0.43, p < .0001). Fewer patients of the EVR group received treatment for CMV (21.8% vs. 47.1%, p = .0007). EVR was discontinued in 31 (35.6%) patients. Among the 56 patients with ongoing EVR treatment, only 7.4% received treatment for CMV. In conclusion, EVR prevents CMV DNAemia requiring treatment in seropositive recipients as long as it is tolerated and maintained.
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mTOR inhibitors in a patient with lupus nephritis; why not? Nefrologia 2022. [DOI: 10.1016/j.nefro.2022.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Bacterial and Viral Infection and Sepsis in Kidney Transplanted Patients. Biomedicines 2022; 10:biomedicines10030701. [PMID: 35327510 PMCID: PMC8944970 DOI: 10.3390/biomedicines10030701] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 02/05/2023] Open
Abstract
Kidney transplanted patients are a unique population with intrinsic susceptibility to viral and bacterial infections, mainly (but not exclusively) due to continuous immunosuppression. In this setting, infectious episodes remain among the most important causes of death, with different risks according to the degree of immunosuppression, time after transplantation, type of infection, and patient conditions. Prevention, early diagnosis, and appropriate therapy are the goals of infective management, taking into account that some specific characteristics of transplanted patients may cause a delay (the absence of fever or inflammatory symptoms, the negativity of serological tests commonly adopted for the general population, or the atypical anatomical presentation depending on the surgical site and graft implantation). This review considers the recent available findings of the most common viral and bacterial infection in kidney transplanted patients and explores risk factors and outcomes in septic evolution.
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Abstract
Infections remain a common complication of solid-organ transplantation. Most infections in the first month after transplant are typically health care-associated infections, whereas late infections, beyond 6-12 months, are community-acquired infections. Opportunistic infections most frequently present in the first 12 months post-transplant and can be modulated on prior exposures and use of prophylaxis. In this review, we summarize the current epidemiology of postkidney transplant infections with a focus on key viral (BK polyomavirus, cytomegalovirus, Epstein-Barr virus, and norovirus), bacterial (urinary tract infections and Clostridioides difficile colitis), and fungal infections. Current guidelines for safe living post-transplant are also summarized. Literature supporting prophylaxis and vaccination is also provided.
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Immunosuppression in the Age of Precision Medicine. Semin Nephrol 2022; 42:86-98. [DOI: 10.1016/j.semnephrol.2022.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Immunosuppressive Drugs. ENCYCLOPEDIA OF INFECTION AND IMMUNITY 2022. [PMCID: PMC8987166 DOI: 10.1016/b978-0-12-818731-9.00068-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Immunosuppressant is a class of medicines that inhibit or decrease the intensity of the immune response in the body. Most of these medications are used to allow the body less likely to resist a transplanted organ. In solid organ transplantation, immunosuppressive agents are needed for the activation of early-stage immunosuppression, the management of late-stage immunosuppression or for the maintenance of organ rejection. The emergence of novel agents and improvements in immunosuppression regimens after transplantation are significant factors leading to this progress. However, these drugs also increase the risk of infection, cancers and specific adverse side effects specific to each agent in patients particularly in pregnant women and fertility issues. Corona virus disease being hot topic of debate is has given positive outcome to immunosuppressive drugs however need more attention in future. Transplant centers across the world utilize multiple immunosuppression protocols; nevertheless, each patient can require an individually formulated immunosuppression regimen to manage the advantages and possible damage of treatment thus eliminating the likelihood of their primary disease recurrence.
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Abstract
Polyomavirus BK virus (BKPyV) infection is an important complication of kidney transplantation and allograft failure. The prevalence of viremia is 10%-15%, compared with BK-associated nephropathy (BKPyVAN) at 3%-5%. Given that there are no effective antiviral prophylaxis or treatment strategies for BKPyVAN, active screening to detect BKPyV viremia is recommended, particularly during the early posttransplant period. Immunosuppression reduction to allow viral clearance may avoid progression to severe and irreversible allograft damage. The frequency and duration of screening are highly variable between transplant centers because the evidence is reliant largely on observational data. While the primary treatment goals center on achieving viral clearance through immunosuppression reduction, prevention of subsequent acute rejection, premature graft loss, and return to dialysis remain as major challenges. Treatment strategies for BKPyV infection should be individualized to the recipient's underlying immunological risk and severity of the allograft infection. Efficacy data for adjuvant therapies including intravenous immunoglobulin and cidofovir are sparse. Future well-powered and high-quality randomized controlled trials are needed to inform evidence-based clinical practice for the management of BKPy infection.
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American Society for Transplantation and Cellular Therapy Series: #4 - Cytomegalovirus treatment and management of resistant or refractory infections after hematopoietic cell transplantation. Transplant Cell Ther 2021; 27:957-967. [PMID: 34560310 DOI: 10.1016/j.jtct.2021.09.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 09/15/2021] [Indexed: 11/29/2022]
Abstract
The Practice Guidelines Committee of the American Society of Transplantation and Cellular Therapy (ASTCT) partnered with its Transpl. Infect. Dis. Special Interest Group (TID-SIG) to update its 2009 compendium-style infectious disease guidelines for hematopoietic cell transplantation (HCT). A new approach was employed with the goal of better serving clinical providers by publishing each standalone topic in the infectious diseases series as a concise format of frequently asked questions (FAQ), tables, and figures. Adult and pediatric infectious diseases and HCT content experts developed and answered FAQs. Topics were finalized with harmonized recommendations that were made by assigning an A through E strength of recommendation paired with a level of supporting evidence graded I through III. The fourth topic in the series focuses on the management and treatment of cytomegalovirus (CMV) resistant and refractory infections. The diagnosis, definitions of resistant and refractory CMV, risk factors, virological genotypes and treatment algorithms are reviewed.
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Adverse Effects of Immunosuppression: Infections. Handb Exp Pharmacol 2021; 272:287-314. [PMID: 34671868 DOI: 10.1007/164_2021_550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Immunosuppressive therapies are currently indicated for a wide range of diseases. As new agents emerge and indications evolve the landscape grows increasingly complex. Therapies can target pathologic immune system over-activation in rheumatologic or autoimmune disease, or conditioning and graft versus host disease (GVHD) prophylactic regimens may eliminate or inhibit host immune function to improve graft survival and risk of complication in solid organ transplantation (SOT) or hematopoietic stem cell transplantation (HSCT). With immunosuppressive therapy, infections occur. Complex disease states, host factors, and concomitant therapies contribute to a "net state" of immunosuppression that must be considered and may confound perceived increased infection risks in patients receiving treatment.
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Cytomegalovirus infection in kidney transplant patients: Prevalence, risk factors, and impact on outcome - A local multicentre experience. Transpl Immunol 2021; 69:101473. [PMID: 34547416 DOI: 10.1016/j.trim.2021.101473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 09/16/2021] [Accepted: 09/16/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND CMV infection prevalence in kidney transplant recipients (KTR) is reported to be high in the literature, reaching rates of over 80%. OBJECTIVES The primary endpoints were the evaluation of the prevalence, the risks factors, and the effects of CMV infection on graft function and survival, as well as patient survival at three years after kidney transplantation. MATERIAL AND METHODS We retrospectively reviewed the medical records of 288 kidney transplant patients operated in three Lebanese transplant centers between 1998 and 2017 with three years of follow-up. The patients were divided into two groups: those free of any CMV infection (271 patients (94%); Group I) and those who suffered from CMV infection (17 patients (6%); Group II). RESULTS Baseline demographics of the two groups were similar, including recipient and donor gender and age, cause of renal disease, recipient body mass index, pre-transplant fasting blood sugar and dialysis duration, HLA matching between donor and recipient, degree of sensitization in the recipient, type of CMV prophylaxis, maintenance immunosuppression and immunological characteristics. The prevalence of CMV infection is 5.9% among KTR. There were significant differences between the two groups concerning the type of induction therapy and the duration of anti-CMV prophylaxis. The rate of infected patients and infectious episodes were significantly higher in Group II. At 3-years, graft function and survival, patient survival, and the rate of new-onset diabetes were similar between the two groups. CONCLUSION The present study is the first to explore the incidence and risk factors of CMV in kidney transplant patients in Lebanon. Comprehensive nationwide studies are therefore necessary to determine the epidemiology and risk factors of CMV infection after kidney transplantation in Lebanon.
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mTOR-Inhibition and COVID-19 in Kidney Transplant Recipients: Focus on Pulmonary Fibrosis. Front Pharmacol 2021; 12:710543. [PMID: 34497515 PMCID: PMC8419255 DOI: 10.3389/fphar.2021.710543] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 08/11/2021] [Indexed: 12/24/2022] Open
Abstract
Kidney transplant recipients are at high risk of developing severe COVID-19 due to the coexistence of several transplant-related comorbidities (e.g., cardiovascular disease, diabetes) and chronic immunosuppression. As a consequence, a large part of SARS-CoV-2 infected patients have been managed with a reduction of immunosuppression. The mTOR-I, together with antimetabolites, have been often discontinued in order to minimize the risk of pulmonary toxicity and to antagonize pharmacological interaction with antiviral/anti-inflammatory drugs. However, at our opinion, this therapeutic strategy, although justified in kidney transplant recipients with severe COVID-19, should be carefully evaluated in asymptomatic/paucisymptomatic patients in order to avoid the onset of acute allograft rejections, to potentially exploit the mTOR-I antiviral properties, to reduce proliferation of conventional T lymphocytes (which could mitigate the cytokine storm) and to preserve Treg growth/activity which could reduce the risk of progression to severe disease. In this review, we discuss the current literature regarding the therapeutic potential of mTOR-Is in kidney transplant recipients with COVID-19 with a focus on pulmonary fibrosis.
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Individualized management of cytomegalovirus in solid organ transplant recipients. EXPERT REVIEW OF PRECISION MEDICINE AND DRUG DEVELOPMENT 2021. [DOI: 10.1080/23808993.2021.1964951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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A Current Review of the Etiology, Clinical Features, and Diagnosis of Urinary Tract Infection in Renal Transplant Patients. Diagnostics (Basel) 2021; 11:diagnostics11081456. [PMID: 34441390 PMCID: PMC8392421 DOI: 10.3390/diagnostics11081456] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 07/26/2021] [Accepted: 08/05/2021] [Indexed: 12/23/2022] Open
Abstract
Urinary tract infection (UTI) represents the most common infection after kidney transplantation and remains a major cause of morbidity and mortality in kidney transplant (KT) recipients, with a potential impact on graft survival. UTIs after KT are usually caused by Gram-negative microorganisms. Other pathogens which are uncommon in the general population should be considered in KT patients, especially BK virus since an early diagnosis is necessary to improve the prognosis. UTIs following kidney transplantation are classified into acute simple cystitis, acute pyelonephritis/complicated UTI, and recurrent UTI, due to their different clinical presentation, prognosis, and management. Asymptomatic bacteriuria (ASB) represents a frequent finding after kidney transplantation, but ASB is considered to be a separate entity apart from UTI since it is not necessarily a disease state. In fact, current guidelines do not recommend routine screening and treatment of ASB in KT patients, since a beneficial effect has not been shown. Harmful effects such as the development of multidrug-resistant (MDR) bacteria and a higher incidence of Clostridium difficile diarrhea have been associated with the antibiotic treatment of ASB.
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Low-dose rapamycin does not impair vascular integrity and tubular regeneration after kidney transplantation in rats. Sci Rep 2021; 11:16270. [PMID: 34381142 PMCID: PMC8358014 DOI: 10.1038/s41598-021-95790-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 07/16/2021] [Indexed: 11/23/2022] Open
Abstract
mTOR inhibitors offer advantages after kidney transplantation including antiviral and antitumor activity besides facilitating low calcineurin inhibitor exposure to reduce nephrotoxicity. Concerns about adverse effects due to antiproliferative and antiangiogenic properties have limited their clinical use particularly early after transplantation. Interference with vascular endothelial growth factor (VEGF)-A, important for physiologic functioning of renal endothelial cells and tubular epithelium, has been implicated in detrimental renal effects of mTOR inhibitors. Low doses of Rapamycin (loading dose 3 mg/kg bodyweight, daily doses 1.5 mg/kg bodyweight) were administered in an allogenic rat kidney transplantation model resulting in a mean through concentration of 4.30 ng/mL. Glomerular and peritubular capillaries, tubular cell proliferation, or functional recovery from preservation/reperfusion injury were not compromised in comparison to vehicle treated animals. VEGF-A, VEGF receptor 2, and the co-receptor Neuropilin-1 were upregulated by Rapamycin within 7 days. Rat proximal tubular cells (RPTC) responded in vitro to hypoxia with increased VEGF-A and VEGF-R1 expression that was not suppressed by Rapamycin at therapeutic concentrations. Rapamycin did not impair proliferation of RPTC under hypoxic conditions. Low-dose Rapamycin early posttransplant does not negatively influence the VEGF network crucial for recovery from preservation/reperfusion injury. Enhancement of VEGF signaling peritransplant holds potential to further improve outcomes.
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Chronic Kidney Allograft Disease: New Concepts and Opportunities. Front Med (Lausanne) 2021; 8:660334. [PMID: 34336878 PMCID: PMC8316649 DOI: 10.3389/fmed.2021.660334] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 06/10/2021] [Indexed: 12/12/2022] Open
Abstract
Chronic kidney disease (CKD) is increasing in most countries and kidney transplantation is the best option for those patients requiring renal replacement therapy. Therefore, there is a significant number of patients living with a functioning kidney allograft. However, progressive kidney allograft functional deterioration remains unchanged despite of major advances in the field. After the first post-transplant year, it has been estimated that this chronic allograft damage may cause a 5% graft loss per year. Most studies focused on mechanisms of kidney graft damage, especially on ischemia-reperfusion injury, alloimmunity, nephrotoxicity, infection and disease recurrence. Thus, therapeutic interventions focus on those modifiable factors associated with chronic kidney allograft disease (CKaD). There are strategies to reduce ischemia-reperfusion injury, to improve the immunologic risk stratification and monitoring, to reduce calcineurin-inhibitor exposure and to identify recurrence of primary renal disease early. On the other hand, control of risk factors for chronic disease progression are particularly relevant as kidney transplantation is inherently associated with renal mass reduction. However, despite progress in pathophysiology and interventions, clinical advances in terms of long-term kidney allograft survival have been subtle. New approaches are needed and probably a holistic view can help. Chronic kidney allograft deterioration is probably the consequence of damage from various etiologies but can be attenuated by kidney repair mechanisms. Thus, besides immunological and other mechanisms of damage, the intrinsic repair kidney graft capacity should be considered to generate new hypothesis and potential therapeutic targets. In this review, the critical risk factors that define CKaD will be discussed but also how the renal mechanisms of regeneration could contribute to a change chronic kidney allograft disease paradigm.
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Hypomagnesemia Is a Risk Factor for Infections after Kidney Transplantation: A Retrospective Cohort Analysis. Nutrients 2021; 13:nu13041296. [PMID: 33919913 PMCID: PMC8070921 DOI: 10.3390/nu13041296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/07/2021] [Accepted: 04/07/2021] [Indexed: 01/16/2023] Open
Abstract
Introduction: Magnesium (Mg2+) deficiency is a common finding in the early phase after kidney transplantation (KT) and has been linked to immune dysfunction and infections. Data on the association of hypomagnesemia and the rate of infections in kidney transplant recipients (KTRs) are sparse. Methods: We conducted a single-center retrospective cohort study of KTRs transplanted between 2005 and 2015. Laboratory data, including serum Mg2+ (median time of the Mg2+ measurement from KT: 29 days), rate of infections including mainly urinary tract infections (UTI), and common transplant-related viral infections (CMV, polyoma, EBV) in the early phase after KT were recorded. The primary outcome was the incidence of infections within one year after KT, while secondary outcomes were hospitalization due to infection, incidence rates of long-term (up to two years) infections, and all-cause mortality. Results: We enrolled 376 KTRs of whom 229 patients (60.9%) suffered from Mg2+ deficiency defined as a serum Mg2+ < 0.7 mmol/L. A significantly higher incidence rate of UTIs and viral infections was observed in patients with versus without Mg2+ deficiency during the first year after KT (58.5% vs. 47.6%, p = 0.039 and 69.9% vs. 51.7%, p < 0.001). After adjustment for potential confounders, serum Mg2+ deficiency remained an independent predictor of both UTIs and viral infections (odds ratio (OR): 1.73, 95% CI: 1.04–2.86, p = 0.035 and OR: 2.05, 95% CI: 1.23–3.41, p = 0.006). No group differences according to Mg2+ status in hospitalizations due to infections and infection incidence rates in the 12–24 months post-transplant were observed. In the Cox regression analysis, Mg2+ deficiency was not significantly associated with all-cause mortality (HR: 1.15, 95% CI: 0.70–1.89, p = 0.577). Conclusions: KTRs suffering from Mg2+ deficiency are at increased risk of UTIs and viral infections in the first year after KT. Interventional studies investigating the effect of Mg2+ supplementation on Mg2+ deficiency and viral infections in KTRs are needed.
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Antivirals against human polyomaviruses: Leaving no stone unturned. Rev Med Virol 2021; 31:e2220. [PMID: 33729628 DOI: 10.1002/rmv.2220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 12/20/2022]
Abstract
Human polyomaviruses (HPyVs) encompass more than 10 species infecting 30%-90% of the human population without significant illness. Proven HPyV diseases with documented histopathology affect primarily immunocompromised hosts with manifestations in brain, skin and renourinary tract such as polyomavirus-associated nephropathy (PyVAN), polyomavirus-associated haemorrhagic cystitis (PyVHC), polyomavirus-associated urothelial cancer (PyVUC), progressive multifocal leukoencephalopathy (PML), Merkel cell carcinoma (MCC), Trichodysplasia spinulosa (TS) and pruritic hyperproliferative keratinopathy. Although virus-specific immune control is the eventual goal of therapy and lasting cure, antiviral treatments are urgently needed in order to reduce or prevent HPyV diseases and thereby bridging the time needed to establish virus-specific immunity. However, the small dsDNA genome of only 5 kb of the non-enveloped HPyVs only encodes 5-7 viral proteins. Thus, HPyV replication relies heavily on host cell factors, thereby limiting both, number and type of specific virus-encoded antiviral targets. Lack of cost-effective high-throughput screening systems and relevant small animal models complicates the preclinical development. Current clinical studies are limited by small case numbers, poorly efficacious compounds and absence of proper randomized trial design. Here, we review preclinical and clinical studies that evaluated small molecules with presumed antiviral activity against HPyVs and provide an outlook regarding potential new antiviral strategies.
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BK Virus-Associated Nephropathy after Renal Transplantation. Pathogens 2021; 10:pathogens10020150. [PMID: 33540802 PMCID: PMC7913099 DOI: 10.3390/pathogens10020150] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 01/29/2021] [Accepted: 01/29/2021] [Indexed: 02/06/2023] Open
Abstract
Recent advances in immunosuppressive therapy have reduced the incidence of acute rejection and improved renal transplantation outcomes. Meanwhile, nephropathy caused by BK virus has become an important cause of acute or chronic graft dysfunction. The usual progression of infection begins with BK viruria and progresses to BK viremia, leading to BK virus associated nephropathy. To detect early signs of BK virus proliferation before the development of nephropathy, several screening tests are used including urinary cytology and urinary and plasma PCR. A definitive diagnosis of BK virus associated nephropathy can be achieved only histologically, typically by detecting tubulointerstitial inflammation associated with basophilic intranuclear inclusions in tubular and/or Bowman’s epithelial cells, in addition to immunostaining with anti-Simian virus 40 large T-antigen. Several pathological classifications have been proposed to categorize the severity of the disease to allow treatment strategies to be determined and treatment success to be predicted. Since no specific drugs that directly suppress the proliferation of BKV are available, the main therapeutic approach is the reduction of immunosuppressive drugs. The diagnosis of subsequent acute rejection, the definition of remission, the protocol of resuming immunosuppression, and long-term follow-up remain controversial.
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CMV high-risk status and posttransplant outcomes in kidney transplant recipients treated with belatacept. Am J Transplant 2021; 21:208-221. [PMID: 32519434 DOI: 10.1111/ajt.16132] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 06/03/2020] [Accepted: 06/03/2020] [Indexed: 01/25/2023]
Abstract
INTRODUCTION Cytomegalovirus (CMV) remains associated with poor outcomes after kidney transplantation (kTx). The impact of belatacept on CMV infection remains understudied. In this study, we assessed the impact of belatacept on patient and graft survivals. METHODS CMV seronegative kTx recipients were included. Patient and graft survival were studied using Kaplan-Meier method, log-rank test. Cox models were used to compare outcomes by CMV risk and immunosuppressive regimen. Incidence and persistence of CMV viremia under belatacept vs tacrolimus were compared. RESULTS Among 308 CMV seronegative recipients, 168 CMV high-risk and 203 belatacept-treated patients were included. High-risk CMV status was associated with lower patient survival and graft survival. Among the CMV high-risk group, patients treated with belatacept presented a higher incidence of CMV viremia, a higher rate of first-line treatment failure and a longer time to virus clearance. They had a nonsignificant trend toward a lower graft survival. CONCLUSION Belatacept-based maintenance immunosuppression is associated with an increased risk of CMV primary-infection and a prolonged course of viral replication in CMV high-risk patients. Further studies are needed to confirm the nonsignificant trend towards a lower graft survival in CMV high-risk patients treated with belatacept and whether it is explained by the higher risk of CMV reactivation and infection.
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5-Year outcomes of the prospective and randomized CISTCERT study comparing steroid withdrawal to replacement of cyclosporine with everolimus in de novo kidney transplant patients. Transpl Int 2020; 34:313-326. [PMID: 33277746 DOI: 10.1111/tri.13798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/13/2020] [Accepted: 12/01/2020] [Indexed: 11/27/2022]
Abstract
Withdrawal of either steroids or calcineurin inhibitors are two strategies to reduce treatment-related side effects and improve long-term outcomes of kidney transplantation. The CISTCERT study compared the efficacy and safety of these two strategies. In this multicenter, randomized controlled trial, 151 incident kidney transplant recipients received cyclosporine (CsA), mycophenolic acid (MPA), and steroids during three months, followed by either steroid withdrawal (CsA/MPA) or replacement of cyclosporine with everolimus (EVL) (EVL/MPA/steroids). 5-year patient survival (89% vs. 86%; P = NS) and death-censored graft survival (95% vs. 96%; P = NS) were comparable in the CsA/MPA and EVL/MPA/steroids arm, respectively. 51 CrEDTA clearance was comparable in the intention-to-treat analysis, but in the on-treatment population, the EVL/MPA/steroids arm exhibited a superior 51 CrEDTA clearance at 1 and 5 years after transplantation (61.6 vs. 52.4, P = 0.05 and 59.1 vs. 46.2ml/min/1.73 m2 , P = 0.042). Numerically more and more severe rejections were observed in the EVL/MPA/steroids arm, which also experienced a higher incidence of posttransplant diabetes (26% vs. 6%, P = 0.0016) and infections. No significant differences were observed in cardiovascular outcomes and malignancy. Both regimens provide an excellent long-term patient survival and graft survival. Regarding graft function, EVL/MPA/steroids is an attractive strategy for patients with good tolerability who remain free of rejection. (ClinicalTrials.gov number: NCT00903188; EudraCT Number 2007-005844-26).
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Clinical features of BK-polyomavirus and cytomegalovirus co-infection after kidney transplantation. Sci Rep 2020; 10:22406. [PMID: 33376243 PMCID: PMC7772341 DOI: 10.1038/s41598-020-79799-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 12/11/2020] [Indexed: 02/07/2023] Open
Abstract
BK polyomavirus (BKPyV) and cytomegalovirus (CMV) are the main viral pathogens affecting the graft and recipient outcome after allogenic kidney transplantation. It has recently been found that infection with both viruses has a greater impact on kidney graft function than a single infection. We retrospectively analyzed a cohort of 723 recipients who received kidney transplantation between 2007 and 2015 after living and postmortal donation for differences in risk and outcome parameters regarding BKPyV (DNAemia) and CMV (CMV DNAemia) co-infection compared to sole viremias and to patients without viremia. Of all kidney allograft recipients in our cohort, 8.2% developed co-infection with BKPyV DNAemia and CMV DNAemia, 15.1% showed BKPyV viremia alone and 25.2% sole CMV DNAemia. Acute rejection was closely linked with co-infection (multivariable analysis, p = 0.001). Despite the fact that the estimated glomerular filtration rate of patients with co-infection was noticeably reduced compared to patients with BKV or CMV infection alone, transplant survival and patient survival were not significantly reduced. Co-infection with BKPyV and CMV in kidney transplanted patients is significantly associated with inferior allograft function. Since co-infection is strongly associated with acute rejection, co-infected individuals should be considered a risk collective.
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Late complications of pancreas transplant. World J Transplant 2020; 10:404-414. [PMID: 33437673 PMCID: PMC7769730 DOI: 10.5500/wjt.v10.i12.404] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/18/2020] [Accepted: 10/09/2020] [Indexed: 02/06/2023] Open
Abstract
To summarize the long-term complications after pancreas transplantation that affect graft function, a literature search was carried out on the long-term complications of pancreatic transplantation, namely, complications from postoperative 3rd mo onwards, in terms of loss of graft function, late infection and vascular complications as pseudoaneurysms. The most relevant reviews and studies were selected to obtain the current evidence on these topics. The definition of graft failure varies among different studies, so it is difficult to evaluate, a standardized definition is of utmost importance to know the magnitude of the problem in all worldwide series. Chronic rejection is the main cause of long-term graft failure, occurring in 10% of patients. From the 3rd mo of transplantation onwards, the main risk factor for late infections is immunosuppression, and patients have opportunistic infections like: Cytomegalovirus, hepatitis B and C viruses, Epstein-Barr virus and varicella-zoster virus; opportunistic bacteria, reactivation of latent infections as tuberculosis or fungal infections. Complete preoperative studies and serological tests should be made in all recipients to avoid these infections, adding perioperative prophylactic treatments when indicated. Pseudoaneurysm are uncommon, but one of the main causes of late bleeding, which can be fatal. The treatment should be performed with radiological endovascular approaches or open surgery in case of failure. Despite all therapeutic options for the complications mentioned above, transplantectomy is a necessary option in approximately 50% of relaparotomies, especially in life-threatening complications. Late complications in pancreatic transplantation threatens long-term graft function. An exhaustive follow-up as well as a correct immunosuppression protocol are necessary for prevention.
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Effect of everolimus-based drug regimens on CMV-specific T-cell functionality after renal transplantation: 12-month ATHENA subcohort-study results. Eur J Immunol 2020; 51:943-955. [PMID: 33306229 DOI: 10.1002/eji.202048855] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/15/2020] [Accepted: 12/07/2020] [Indexed: 02/06/2023]
Abstract
Post-transplant cytomegalovirus (CMV) infections and increased viral replication are associated with CMV-specific T-cell anergy. In the ATHENA-study, de-novo everolimus (EVR) with reduced-exposure tacrolimus (TAC) or cyclosporine (CyA) showed significant benefit in preventing CMV infections in renal transplant recipients as compared to standard TAC + mycophenolic acid (MPA). However, immunomodulatory mechanisms for this effect remain largely unknown. Ninety patients from the ATHENA-study completing the 12-month visit on-treatment (EVR + TAC n = 28; EVR + CyA n = 19; MPA + TAC n = 43) were included in a posthoc analysis. Total lymphocyte subpopulations were quantified. CMV-specific CD4 T cells were determined after stimulation with CMV-antigen, and cytokine-profiles and various T-cell anergy markers were analyzed using flow cytometry. While 25.6% of MPA + TAC-treated patients had CMV-infections, no such events were reported in EVR-treated patients. Absolute numbers of lymphocyte subpopulations were comparable between arms, whereas the percentage of regulatory T cells was significantly higher with EVR + CyA versus MPA + TAC (p = 0.019). Despite similar percentages of CMV-specific T cells, their median expression of CTLA-4 and PD-1 was lower with EVR + TAC (p < 0.05 for both) or EVR + CyA (p = 0.045 for CTLA-4) compared with MPA + TAC. Moreover, mean percentages of multifunctional CMV-specific T cells were higher with EVR + TAC (27.2%) and EVR + CyA (29.4%) than with MPA + TAC (19.0%). In conclusion, EVR-treated patients retained CMV-specific T-cell functionality, which may contribute to enhanced protection against CMV infections.
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Prospective Study of Long Noncoding RNA, MGAT3-AS1, and Viremia of BK Polyomavirus and Cytomegalovirus in Living Donor Renal Transplant Recipients. Kidney Int Rep 2020; 5:2218-2227. [PMID: 33305115 PMCID: PMC7710814 DOI: 10.1016/j.ekir.2020.09.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 08/04/2020] [Accepted: 09/02/2020] [Indexed: 11/28/2022] Open
Abstract
Introduction Viremia after renal transplantation is a major cause of morbidity and mortality and treatment opportunities are limited. Tests to determine the increased risk for viremia would be preferable. Methods In a prospective, single-center study, we conducted follow-up of 163 renal transplant recipients after incident living donor renal transplantation. We determined a long noncoding RNA, β-1,4-mannosylglycoprotein 4-β-N-acetylglucosaminyltransferase-antisense1 (MGAT3-AS1/beta-actin ratio), in peripheral blood mononuclear cells. Viremia of BK polyomavirus and cytomegalovirus was diagnosed with more than 1000 plasma copies/ml within the first 3 postoperative months. The MGAT3-AS1/beta-actin ratio was assessed before viremia was determined. Results Receiver operator characteristics curve analysis showed a median MGAT3-AS1/beta-actin ratio cutoff value of 4.45 × 10–6 to indicate viremia after transplantation. Samples for 11 of 66 renal transplant recipients (17%) with MGAT3-AS1/beta-actin ratios below 4.45 × 10–6 showed viremia of BK polyomavirus and cytomegalovirus compared with only 6 of 97 renal transplant recipients (6%) with higher MGAT3-AS1/beta-actin ratios (odds ratio [OR]: 3.03; 95% confidence interval [CI]: 1.06–8.67 by Fisher exact test). Furthermore, samples for 6 of 66 renal transplant recipients (9%) with MGAT3-AS1/beta-actin ratios below 4.45 × 10–6 showed BK polyomavirus viremia compared with none of 97 renal transplant recipients (0%) with higher MGAT3-AS1/beta-actin ratios (OR: 20.95; 95% CI, 1.16–378.85 by Fisher exact test). Multivariate logistic regression analysis confirmed that MGAT3-AS1/beta-actin ratios below the cutoff level remained significantly associated with viremia after transplant. Lower MGAT3-AS1/beta-actin ratios occurred with rituximab-containing induction therapy. Conclusions A low MGAT3-AS1/beta-actin ratio indicates an increased risk for viremia of BK polyomavirus and cytomegalovirus in living donor renal transplant recipients.
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The Role of HLA and KIR Immunogenetics in BK Virus Infection after Kidney Transplantation. Viruses 2020; 12:v12121417. [PMID: 33317205 PMCID: PMC7763146 DOI: 10.3390/v12121417] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 12/04/2020] [Accepted: 12/08/2020] [Indexed: 12/13/2022] Open
Abstract
BK virus (BKV) is a polyomavirus with high seroprevalence in the general population with an unremarkable clinical presentation in healthy people, but a potential for causing serious complications in immunosuppressed transplanted patients. Reactivation or primary infection in kidney allograft recipients may lead to allograft dysfunction and subsequent loss. Currently, there is no widely accepted specific treatment for BKV infection and reduction of immunosuppressive therapy is the mainstay therapy. Given this and the sequential appearance of viruria-viremia-nephropathy, screening and early detection are of utmost importance. There are numerous risk factors associated with BKV infection including genetic factors, among them human leukocyte antigens (HLA) and killer cell immunoglobulin-like receptors (KIR) alleles have been shown to be the strongest so far. Identification of patients at risk for BKV infection would be useful in prevention or early action to reduce morbidity and progression to frank nephropathy. Assessment of risk involving HLA ligands and KIR genotyping of recipients in the pre-transplant or early post-transplant period might be useful in clinical practice. This review summarizes current knowledge of the association between HLA, KIR and BKV infection and potential future directions of research, which might lead to optimal utilization of these genetic markers.
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Cytomegalovirus after kidney transplantation in 2020: moving towards personalized prevention. Nephrol Dial Transplant 2020; 37:810-816. [PMID: 33280028 DOI: 10.1093/ndt/gfaa249] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Indexed: 12/24/2022] Open
Abstract
Cytomegalovirus (CMV)-related complications after kidney transplantation remain a substantial challenge. Rather than applying one preventive strategy to all at-risk patients, we can now adapt our strategy at the individual patient level. Antiviral prophylaxis or a strict pre-emptive strategy may be optimal for patients at the highest risk for CMV, while patients at lower risk may benefit particularly from pre-emptive monitoring and the administration of therapy only if needed. CMV-specific T-cell assays may be useful for further refining the pre-transplant determination of CMV risk, and for guiding decisions about antiviral therapy need or duration. An immunosuppressive regimen including a mammalian target of rapamycin inhibitor reduces CMV risk and may thus be an attractive option in some patients. New antiviral agents may further expand our therapeutic arsenal in the near future, and the prospects of CMV vaccination and adoptive T-cell therapy appear to be on the horizon.
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Kidney transplantation using alemtuzumab, belatacept, and sirolimus: Five-year follow-up. Am J Transplant 2020; 20:3609-3619. [PMID: 32515087 DOI: 10.1111/ajt.16121] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 05/21/2020] [Accepted: 05/28/2020] [Indexed: 01/25/2023]
Abstract
Kidney transplant outcomes are limited by toxicities associated with calcineurin inhibitors and steroids. This trial was conducted to determine whether a costimulation blockade (CoB)-based regimen could achieve acceptable long-term outcomes and graft survival could be maintained solely with CoB. Forty patients underwent alemtuzumab induction followed by belatacept and sirolimus maintenance therapy. Patients were offered weaning to belatacept monotherapy after 1 year and followed for 5 years. Five-year patient and graft survival rates were 100% and 95%, respectively. Graft function remained stable with a mean estimated glomerular filtration rates of 67 ± 21 and 71 ± 19 at 36 and 60 months, respectively. There was no clinical rejection in the first year; subclinical rejection was detected by protocol biopsy in 4 patients. Twelve patients were successfully weaned to belatacept monotherapy. Cytomegalovirus and Epstein-Barr virus reactivations were well controlled, but 9 patients experienced transient BK viremia during the first year. Alemtuzumab produced profound lymphopenia followed by gradual T cell and more rapid B cell reconstitution to a repertoire deviated toward naïve cells with increased regulatory T cells. This regimen effectively prevents allograft rejection without using steroids or calcineurin inhibitors, enriches for naïve cells susceptible to control with CoB, and permits control of rejection with belatacept monotherapy in selected patients.
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Abstract
Reactivation of BK virus (BKV) remains a dreaded complication in immunosuppressed states. Conventionally, BKV is known as a cause for BKV-associated nephropathy and allograft dysfunction in kidney transplant recipients. However, emerging studies have shown its negative impact on native kidney function and patient survival in other transplants and its potential role in diseases such as cancer. Because BKV-associated nephropathy is driven by immunosuppression, reduction in the latter is a convenient standard of care. However, this strategy is risk prone due to the development of donor-specific antibodies affecting long-term allograft survival. Despite its pathogenic role, there is a distinct lack of effective anti-BKV therapeutics. This limitation combined with increased morbidity and health care cost of BKV-associated diseases add to the complexity of BKV management. While summarizing recent advances in the pathogenesis of BKV-associated nephropathy and its reactivation in other organ transplants, this review illustrates the limitations of current and emerging therapeutic options and provides a compelling argument for an effective targeted anti-BKV drug.
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Opportunistic infections after conversion to belatacept in kidney transplantation. Nephrol Dial Transplant 2020; 35:336-345. [PMID: 32030416 DOI: 10.1093/ndt/gfz255] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 10/29/2019] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Belatacept (bela) rescue therapy seems to be a valuable option for calcineurin inhibitor chronic toxicity in kidney transplantation. Nevertheless, the risk of infection associated with bela is not well reported. METHODS We report the rate of opportunistic infections (OPI) after a switch to bela in a multicentric cohort of 280 kidney transplant patients. RESULTS Forty-two OPI occurred in 34 patients (12.1%), on average 10.8 ± 11.3 months after the switch. With a cumulative exposure of 5128 months of bela treatment, we found an incidence of 0.008 OPI/month of exposure, and 9.8 OPI/100 person-years. The most common OPI was cytomegalovirus (CMV) disease in 18/42 OPI (42.9%) and pneumocystis pneumonia in 12/42 OPI (28.6%). Two patients presented a progressive multifocal leucoencephalopathy and two patients developed a cerebral Epstein-Barr virus-induced post-transplant lymphoproliferative disease. OPI led to death in 9/34 patients (26.5%) and graft failure in 4/34 patients (11.8%). In multivariate analysis, estimated glomerular filtration rate <25/mL/min/1.73 m2 on the day of the switch and the use of immunosuppressive agents before transplantation were associated with the occurrence of OPI. We found a higher rate of infection-related hospitalization (24.1 versus 12.3/100 person-years, P = 0.0007) and also a higher rate of OPI (13.2 versus 6.7/100 person-years, P = 0.005) in the early conversion group (within 6 months). CONCLUSIONS The risk of OPI is significant post-conversion to bela and may require additional monitoring and prophylactic therapy, particularly regarding pneumocystis pneumonia and CMV disease. These data need to be confirmed in a larger case-control study.
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A case-control study to assess the role of polyomavirus in transplant complications: Where do we stand? Transpl Infect Dis 2020; 22:e13432. [PMID: 32738811 DOI: 10.1111/tid.13432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 07/22/2020] [Accepted: 07/24/2020] [Indexed: 11/27/2022]
Abstract
PURPOSE The study's aim was to assess whether polyomavirus DNAemia screening was associated with different outcomes in patients with positive viremia compared with negative viremia. METHODS Case-control retrospective study of patients with polyomavirus DNAemia (viremia > 1000 copies/mL) matched 1:1 with controls. Control group consists of the patient who received a transplant immediately before or after each identified case and did have nil viremia. FINDING Ultimately, 120 cases of BK polyomavirus (BKPyV) were detected and matched with 130 controls. Of these, 54 were adult kidney transplant recipients (KTRs), 43 were pediatric KTRs, and 23 were undergoing hemato-oncologic therapy, of which 20 were undergoing hematopoietic stem cell transplantation. The odds ratio (OR) for overall risk of poorer outcomes in cases versus controls was 16.07 (95% CI: 5.55-46.54). The unfavorable outcome of switching the immunosuppressive drug (ISD) (14/40,35%) was no different from that of those treated with reduced ISD doses (31/71, 43.6%, P = .250). Acute rejection or graft-versus-host disease, previous transplant, and intensity of immunosuppression (4 ISDs plus induction or conditioning) were risk factors for BKPyV-DNAemia (OR: 13.96, 95% CI: 11.25-15.18, P < .001; OR: 6.14, 95% CI: 3.91-8.80, P < .001; OR: 5.53, 95% CI: 3.37-7.30, P < .001, respectively). CONCLUSIONS Despite viremia screening, dose reduction, and change in therapeutic protocol, patients with positive BKPyV-DNAemia present poorer outcomes and unfavorable results.
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Prevention and Management of CMV Infections after Liver Transplantation: Current Practice in German Transplant Centers. J Clin Med 2020; 9:jcm9082352. [PMID: 32717978 PMCID: PMC7465768 DOI: 10.3390/jcm9082352] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/15/2020] [Accepted: 07/20/2020] [Indexed: 12/22/2022] Open
Abstract
Human cytomegalovirus (CMV) remains a major cause of mortality and morbidity in human liver transplant recipients. Anti-CMV therapeutics can be used to prevent or treat CMV in liver transplant recipients, but their toxicity needs to be balanced against the benefits. The choice of prevention strategy (prophylaxis or preemptive treatment) depends on the donor/recipient sero-status but may vary between institutions. We conducted a series of consultations and roundtable discussions with German liver transplant center representatives. Based on 20 out of 22 centers, we herein summarize the current approaches to CMV prevention and treatment in the context of liver transplantation in Germany. In 90% of centers, transient prophylaxis with ganciclovir or valganciclovir was standard of care in high-risk (donor CMV positive, recipient CMV naive) settings, while preemptive therapy (based on CMV viremia detected during (bi) weekly PCR testing for circulating CMV-DNA) was preferred in moderate- and low-risk settings. Duration of prophylaxis or intense surveillance was 3-6 months. In the case of CMV infection, immunosuppression was adapted. In most centers, antiviral treatment was initiated based on PCR results (median threshold value of 1000 copies/mL) with or without symptoms. Therefore, German transplant centers report similar approaches to the prevention and management of CMV infection in liver transplantation.
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Pure Red Cell Aplasia Related to Parvovirus B19 Infection in Simultaneous Pancreas and Kidney Recipient: A Case Report. Transplant Proc 2020; 52:2539-2543. [PMID: 32591136 DOI: 10.1016/j.transproceed.2020.01.127] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 01/26/2020] [Indexed: 12/11/2022]
Abstract
A 42-year-old woman received a simultaneous pancreas and kidney transplantation (SPK). Immunosuppression consisted of tacrolimus modified release, prednisone, mycophenolate mofetil (MMF), and thymoglobulin as induction. The function of both grafts was good. Eight months after SPK, the patient suffered from weakness and arthralgia. Normocytic anemia with reticulocytopenia was revealed. In a bone marrow examination, giant pronormoblasts were found. Immunohistochemical staining of bone marrow and serum examination were positive for Parvovirus B19 (Parvo B19) confirming diagnosis of pure red cell aplasia (PRCA).The treatment consisted of MMF withdrawal, red-cell transfusions, immunoglobulins subcutaneously (SCIg) and immunosuppression reduction. Rapid improvement was observed with the rise of reticulocyte count and hemoglobin. Two months after the achievement of remission, the low dose of everolimus was added considering the high risk of rejection and antiviral potential of mTOR inhibitors. Three months later, PRCA relapsed. Retherapy with SCIg was still effective. Subsequent SCIg was supplemented due to low reticulocyte count and recurrent herpes zoster. The replication of Parvo B19 was persistent (serum qualitative test). Everolimus was withdrawn after 9 months of therapy due to the recurrence of PRCA and serious infections. The observation period after PRCA diagnosis lasts for 15 months. The patient is in good condition with no anemia and excellent grafts function. In conclusion, pure red cell aplasia related to Parvo B19 infection should be considered in transplant recipients with normocytic anemia and reticulocytopenia. The treatment with immunoglobulin G and immunosuppression reduction is an effective therapy. The role of everolimus in Parvo B19 infection requires future studies.
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Everolimus for BKV nephropathy in kidney transplant recipients: a prospective, controlled study. J Nephrol 2020; 34:531-538. [PMID: 32533451 DOI: 10.1007/s40620-020-00777-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 06/06/2020] [Indexed: 12/18/2022]
Abstract
There is no specific therapy for polyoma BK virus nephropathy (BKVN) in kidney transplant recipients, a condition associated with poor outcomes. Everolimus showed promising antiviral effects, but data from prospective studies are limited. Therefore, we converted ten consecutive kidney transplant recipients with biopsy-proven BKVN from standard exposure Calcineurin inhibitors and Mycophenolate to Everolimus and reduced exposure Calcineurin inhibitors. Ten patients not administered Everolimus, on reduced exposure Calcineurin inhibitor and halved MPA doses served as controls. All kidney transplant recipients continued steroid therapy. Each patient underwent kidney graft biopsy, BKV replication by PCR, and de novo DSA determination. During a 3-year follow-up no graft loss occurred in kidney transplant recipients on Everolimus but it was observed in 5/10 controls (P = 0.032). eGFR improved on Everolimus and worsened in controls (between group difference + 25.6 ml/min/1.73 m2, 95% CI 10.5-40.7, P = 0.002). BKV replication declined in the Everolimus group alone (from 6.4 ± 0.8 to 3.6 ± 1.6 Log 10 genomic copies, P = 0.0001), and we found a significant inverse relationship between eGFR and BKV genomic copy changes (P = 0.022). Average Calcineurin inhibitors trough levels did not differ between the two study groups during follow-up. By multivariable Cox regression analysis, Everolimus treatment resulted the only significant predictor of survival free of a combined endpoint of graft loss and 57% eGFR reduction (P = 0.02). Kidney transplant recipients on Everolimus had a higher survival free of adverse graft outcome (log-rank test, P = 0.009). In conclusion an Everolimus-based immunosuppressive protocol with minimization of Calcineurin inhibitors and antimetabolite discontinuation effectively treated BKVN in kidney transplant recipients.
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Effect of mTOR inhibitors during CMV disease in kidney transplant recipients: Results of a pilot retrospective study. Microbiol Immunol 2020; 64:520-531. [PMID: 32249964 DOI: 10.1111/1348-0421.12794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 03/28/2020] [Accepted: 03/31/2020] [Indexed: 12/12/2022]
Abstract
mTOR inhibitors exert a preventive effect on cytomegalovirus (CMV) disease in CMV seropositive (R+) kidney transplant recipients, but their impact during the curative treatment of CMV disease in high-risk kidney transplant recipients has not been investigated. We aimed to evaluate the efficacy and tolerance of mTOR inhibitors compared with mycophenolic acid in 63 consecutive kidney transplant recipients (80% of D+R-) suffering from CMV disease with a persistent or a recurrent CMV DNAemia. In this monocentric retrospective study, 16 had their treatment converted to mTOR inhibitors and 47 did not. The Kaplan-Meier curves did not show any significant differences in CMV DNAemia eradication (77% vs. 88% respectively; hazard ratio (HR), 1.648 [95% confidence interval (CI), 0.913-2.973]; log-rank test, P = .132), DNAemia recurrence (36% vs. 47%; HR, 1.517 [95% CI, 0.574-4.007]; log-rank test, P = .448) and CMV clinical recurrence (17% vs. 27%; HR, 1.375 [95% CI, 0.340-5.552]; log-rank test, P = .677) between patients who received mTOR inhibitors and those who did not. These results were confirmed in uni- and multivariate time-dependent Cox regressions. In summary, conversion from mycophenolic acid to mTOR inhibitors seems inadequate for improving CMV clearance or in better preventing CMV recurrences during severe or persistent CMV disease.
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