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Hirt-Minkowski P, Schaub S. Urine CXCL10 as a biomarker in kidney transplantation. Curr Opin Organ Transplant 2024; 29:138-143. [PMID: 38235748 PMCID: PMC10919271 DOI: 10.1097/mot.0000000000001135] [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] [Indexed: 01/19/2024]
Abstract
PURPOSE OF REVIEW Urine CXCL10 is a promising biomarker for posttransplant renal allograft monitoring but is currently not widely used for clinical management. RECENT FINDINGS Large retrospective studies and data from a prospective randomized trial as well as a prospective cohort study demonstrate that low urine CXCL10 levels are associated with a low risk of rejection and can exclude BK polyomavirus replication with high certainty. Urine CXCL10 can either be used as part of a multiparameter based risk assessment tool, or as an individual biomarker taking relevant confounders into account. A novel Luminex-based CXCL10 assay has been validated in a multicenter study, and proved to be robust, reproducible, and accurate. SUMMARY Urine CXCL10 is a well characterized inflammation biomarker, which can be used to guide performance of surveillance biopsies. Wide implementation into clinical practice depends on the availability of inexpensive, thoroughly validated assays with approval from regulatory authorities.
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Affiliation(s)
| | - Stefan Schaub
- Clinic for Transplantation Immunology and Nephrology
- HLA-Diagnostic and lmmunogenetics, Department of Laboratory Medicine, University Hospital Basel, Basel, Switzerland
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Hirt-Minkowski P, Handschin J, Stampf S, Hopfer H, Menter T, Senn L, Hönger G, Wehmeier C, Amico P, Steiger J, Koller M, Dickenmann M, Schaub S. Randomized Trial to Assess the Clinical Utility of Renal Allograft Monitoring by Urine CXCL10 Chemokine. J Am Soc Nephrol 2023; 34:1456-1469. [PMID: 37228005 PMCID: PMC10400101 DOI: 10.1681/asn.0000000000000160] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 04/12/2023] [Indexed: 05/27/2023] Open
Abstract
SIGNIFICANCE STATEMENT This study is the first randomized controlled trial to investigate the clinical utility of a noninvasive monitoring biomarker in renal transplantation. Although urine CXCL10 monitoring could not demonstrate a beneficial effect on 1-year outcomes, the study is a rich source for future design of trials aiming to explore the clinical utility of noninvasive biomarkers. In addition, the study supports the use of urine CXCL10 to assess the inflammatory status of the renal allograft. BACKGROUND Urine CXCL10 is a promising noninvasive biomarker for detection of renal allograft rejection. The aim of this study was to investigate the clinical utility of renal allograft monitoring by urine CXCL10 in a randomized trial. METHODS We stratified 241 patients, 120 into an intervention and 121 into a control arm. In both arms, urine CXCL10 levels were monitored at three specific time points (1, 3, and 6 months post-transplant). In the intervention arm, elevated values triggered performance of an allograft biopsy with therapeutic adaptations according to the result. In the control arm, urine CXCL10 was measured, but the results concealed. The primary outcome was a combined end point at 1-year post-transplant (death-censored graft loss, clinical rejection between month 1 and 1-year, acute rejection in 1-year surveillance biopsy, chronic active T-cell-mediated rejection in 1-year surveillance biopsy, development of de novo donor-specific HLA antibodies, or eGFR <25 ml/min). RESULTS The incidence of the primary outcome was not different between the intervention and the control arm (51% versus 49%; relative risk (RR), 1.04 [95% confidence interval, 0.81 to 1.34]; P = 0.80). When including 175 of 241 (73%) patients in a per-protocol analysis, the incidence of the primary outcome was also not different (55% versus 49%; RR, 1.11 [95% confidence interval, 0.84 to 1.47]; P = 0.54). The incidence of the individual end points was not different as well. CONCLUSIONS This study could not demonstrate a beneficial effect of urine CXCL10 monitoring on 1-year outcomes (ClinicalTrials.gov_ NCT03140514 ).
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Affiliation(s)
- Patricia Hirt-Minkowski
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
| | - Joelle Handschin
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
- Molecular Immune Regulation, Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Susanne Stampf
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
| | - Helmut Hopfer
- Department of Pathology, University Hospital Basel, Basel, Switzerland
| | - Thomas Menter
- Department of Pathology, University Hospital Basel, Basel, Switzerland
| | - Lisa Senn
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
| | - Gideon Hönger
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
- Molecular Immune Regulation, Department of Biomedicine, University of Basel, Basel, Switzerland
- HLA-Diagnostics and Immunogenetics, Department of Laboratory Medicine, University Hospital Basel, Basel, Switzerland
| | - Caroline Wehmeier
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
| | - Patrizia Amico
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
| | - Jürg Steiger
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
- Molecular Immune Regulation, Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Michael Koller
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
| | - Michael Dickenmann
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
| | - Stefan Schaub
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
- Molecular Immune Regulation, Department of Biomedicine, University of Basel, Basel, Switzerland
- HLA-Diagnostics and Immunogenetics, Department of Laboratory Medicine, University Hospital Basel, Basel, Switzerland
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Paul RS, Almokayad I, Collins A, Raj D, Jagadeesan M. Donor-derived Cell-free DNA: Advancing a Novel Assay to New Heights in Renal Transplantation. Transplant Direct 2021; 7:e664. [PMID: 33564715 PMCID: PMC7862009 DOI: 10.1097/txd.0000000000001098] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 10/09/2020] [Accepted: 10/13/2020] [Indexed: 02/07/2023] Open
Abstract
Despite advances in transplant immunosuppression, long-term renal allograft outcomes remain suboptimal because of the occurrence of rejection, recurrent disease, and interstitial fibrosis with tubular atrophy. This is largely due to limitations in our understanding of allogeneic processes coupled with inadequate surveillance strategies. The concept of donor-derived cell-free DNA as a signal of allograft stress has therefore rapidly been adopted as a noninvasive monitoring tool. Refining it for effective clinical use, however, remains an ongoing effort. Furthermore, its potential to unravel new insights in alloimmunity through novel molecular techniques is yet to be realized. This review herein summarizes current knowledge and active endeavors to optimize cell-free DNA-based diagnostic techniques for clinical use in kidney transplantation. In addition, the integration of DNA methylation and microRNA may unveil new epigenetic signatures of allograft health and is also explored in this report. Directing research initiatives toward these aspirations will not only improve diagnostic precision but may foster new paradigms in transplant immunobiology.
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Affiliation(s)
- Rohan S. Paul
- Division of Kidney Disease & Hypertension, George Washington University, Washington, DC
| | - Ismail Almokayad
- Division of Kidney Disease & Hypertension, George Washington University, Washington, DC
| | - Ashte Collins
- Division of Kidney Disease & Hypertension, George Washington University, Washington, DC
| | - Dominic Raj
- Division of Kidney Disease & Hypertension, George Washington University, Washington, DC
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Odum JD, Kats A, VanSickle JS, Chadha V, Brewer B, Staggs VS, Warady BA. Characterizing the frequency of modifiable histological changes observed on surveillance biopsies in pediatric kidney allograft recipients. Pediatr Nephrol 2020; 35:2173-2182. [PMID: 32556543 DOI: 10.1007/s00467-020-04624-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 01/06/2023]
Abstract
BACKGROUND Rejection is responsible for just under 50% of graft loss in the pediatric kidney transplant population. Early identification and treatment of allograft injury, specifically modifiable pathologies such as subclinical rejection (SCR), calcineurin inhibitor toxicity, and BK virus nephropathy, may improve allograft survival. Protocol surveillance biopsy (SB) currently offers the earliest opportunity for targeted interventions. METHODS This is a single-center retrospective review of 215 kidney SBs obtained from 2008 to 2016 in 97 pediatric kidney transplant recipients. SBs were obtained at 6, 12, and 24 months post-transplantation. Frequency of abnormal histologic findings, estimated glomerular filtration rate at time of SB, and SB-related complications were recorded. Data were analyzed to investigate possible time trends and the presence of demographic or clinical associations with abnormal histologic findings. RESULTS Potentially modifiable histologic findings were seen in 38.1% of all SBs. SCR was found with increasing frequency across all time points with an estimated 49% increase in the odds of a SCR finding per additional 6 months post-transplantation (aOR 1.49, 95% CI 1.06-2.09, p = 0.022). Among follow-up biopsies in patients who underwent treatment for SCR, 50% had no SCR and 18.8% showed histologic improvement. The complication rate associated with SB was 1.9% (4/215 SBs) and consisted of only minor complications. CONCLUSIONS SBs are safe and offer the opportunity to identify and treat modifiable histologic changes in the pediatric kidney transplant population. The performance of SBs for up to 2 years after transplantation can have meaningful clinical impact.
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Affiliation(s)
- James D Odum
- Division of Graduate Medical Education, Children's Mercy Kansas City, Kansas City, MO, USA
| | - Alexander Kats
- Department of Pathology and Laboratory Medicine, Children's Mercy Kansas City, Kansas City, MO, USA
| | - Judith Sebestyen VanSickle
- Division of Pediatric Nephrology, Children's Mercy Kansas City, 2401 Gillham Road, Kansas City, MO, 64108, USA
| | - Vimal Chadha
- Division of Pediatric Nephrology, Children's Mercy Kansas City, 2401 Gillham Road, Kansas City, MO, 64108, USA
| | - Brenda Brewer
- Division of Pediatric Nephrology, Children's Mercy Kansas City, 2401 Gillham Road, Kansas City, MO, 64108, USA
| | - Vincent S Staggs
- Biostatistics & Epidemiology Core, Children's Mercy Kansas City, Kansas City, MO, USA
| | - Bradley A Warady
- Division of Pediatric Nephrology, Children's Mercy Kansas City, 2401 Gillham Road, Kansas City, MO, 64108, USA.
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Urinary Exosomal MicroRNA Signatures in Nephrotic, Biopsy-Proven Diabetic Nephropathy. J Clin Med 2020; 9:jcm9041220. [PMID: 32340338 PMCID: PMC7231152 DOI: 10.3390/jcm9041220] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 04/18/2020] [Accepted: 04/21/2020] [Indexed: 12/16/2022] Open
Abstract
Diabetic kidney disease (DKD) is the leading cause of chronic kidney disease (CKD). Elucidating the mechanisms underlying proteinuria in DKD is crucial because it is a common problem in DKD-related mortality and morbidity. MicroRNAs (miRs) associated with DKD have been detected in experimental diabetes models and in patients with both diabetes and CKD. Here, we aimed to investigate pathologic miRs in diabetic nephropathy (DN) by prospectively following six nephrotic, biopsy-proven isolated DN patients (enrolled between August 2015 and July 2017) for one year. The urinary exosomes were isolated at the time of the biopsy and the contained miRs were analyzed by next-generation sequencing. The results were compared to the control group, composed of age-, gender-, and CKD stage-matched patients with proteinuric CKD who did not present diabetes. Among the 72 identified miRs, we investigated eight (miR-188-5p, miR-150-3p, miR-760, miR-3677-3p, miR-548ah-3p, miR-548p, miR-320e, and miR-23c) exhibiting the strongest upregulation (13–15 fold) and two (miR-133a-3p and miR-153-3p) with the strongest downregulation (7–9 fold). The functional analysis of these miRs showed that they were involved in known and novel pathways of DN, supporting their pathologic roles. The bioinformatics-based prediction of the target genes of these miRs will inspire future research on the mechanisms underlying DN pathogenesis.
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Technical Considerations and Confounders for Urine CXCL10 Chemokine Measurement. Transplant Direct 2019; 6:e519. [PMID: 32047847 PMCID: PMC6964934 DOI: 10.1097/txd.0000000000000959] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 10/23/2019] [Indexed: 12/16/2022] Open
Abstract
Background. The urine C-X-C motif chemokine 10 (CXCL10) is a promising screening biomarker for renal allograft rejection. The aim of the study was to investigate important technical and biological aspects as well as potential confounders when measuring urine CXCL10. Methods. We analyzed 595 urine samples from 117 patients, who participated in a randomized controlled trial investigating the clinical utility of urine CXCL10 monitoring for posttransplant management. Urine CXCL10 was measured by an immunoassay using electrochemiluminescence. Results. Intraassay coefficient of variation was 2.5%, and interassay coefficient of variation was 10%. Urine CXCL10 remained stable (ie, <10% degradation) for 8 hours at 25°C or 37°C and for 3 days at 4°C. CXCL10 concentrations [pg/mL] strongly correlated with urine CXCL10/creatinine ratios [ng/mmol] (r2 = 0.98; P < 0.0001). Leucocyturia and active BK-polyomavirus infection are associated with higher CXCL10 concentrations, while allograft function, serum CRP, patient age, proteinuria, urine pH, hematuria, squamous epithelia cell count, and bacteriuria did not correlate with urine CXCL10 concentrations. In 145 paired samples obtained within 1–2 weeks, 80% showed a CXCL10/creatinine ratio change of < ±2 ng/mmol or ±50%, respectively. Conclusions. Urine CXCL10 measurement on the used platform is accurate and robust. Leucocyturia and active BK-polyomavirus infection are major confounders, which can be easily detected but represent important diagnostic “blind spots” when using urine CXCL10 to screen for allograft rejection. The intraindividual biological variability of urine CXCL10 within 1–2 weeks is mostly below ±50%, which is still much higher than the technical variability due to sample handling/processing (<20%).
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Switching renal transplant recipients to belatacept therapy: results of a real-life gradual conversion protocol. Transpl Immunol 2019; 56:101207. [PMID: 31071442 DOI: 10.1016/j.trim.2019.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 04/18/2019] [Accepted: 04/26/2019] [Indexed: 01/30/2023]
Abstract
Conversion to belatacept immunosuppression is a therapeutic option for renal-transplant recipients with calcineurin inhibitors (CNI) toxicity, but it associates with high risk of acute rejection. Gradual conversion and serial immune monitoring with urinary chemokine CXCL9 may allow increasing safety of this maneuver. We converted kidney transplant recipients with signs of toxicity to CNI or other immunosuppressive drugs to belatacept over a 2-month period. We monitored renal function, metabolic profile, and circulating lymphocyte subsets. We also quantified urinary CXCL9 over a 12-month follow-up period. Between September 2016 and March 2017, 35 patients were successfully switched to belatacept immunosuppression at 3.3 (1.3-7.2) years after transplant. Two patients had a reversible rise in serum creatinine, associated with acute rejection in one case. Urinary CXCL9 increased before serum creatinine. After conversion, blood pressure and HbA1c significantly declined while eGFR and proteinuria remained stable. The percentage of circulating effector T cells and memory B cells significantly declined. Conversion from CNI to belatacept, in this setting, was feasible and safe, provided it was performed over a 2-month time-period. Monitoring urinary CXCL9 may further increase safety through earlier identification of patients at risk for acute rejection. The procedure associates with improved blood pressure, metabolic profile, and reduced circulating effector T and B cells.
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Schinstock CA, Gandhi MJ. Maintaining the Health of the Renal Allograft: Laboratory and Histologic Monitoring After Kidney Transplantation. Clin Lab Med 2018; 38:607-621. [PMID: 30420056 DOI: 10.1016/j.cll.2018.07.003] [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] [Indexed: 11/18/2022]
Abstract
Advances in posttransplant care, including new immunosuppressive medications have led to excellent short-term renal allograft survival. However, there is a small therapeutic window within which the patient and the clinician must balance the risk of rejection, with side effects such as infection, malignancy, and toxicity. Laboratory testing plays a key role in this ongoing monitoring, which includes relatively simple tests, such as serum creatinine, to complex tests, such as solid-phase assays, used to monitor for donor-specific antibody and surveillance allograft biopsies. This article reviews the role of the laboratory tests and surveillance biopsies in posttransplant monitoring.
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Affiliation(s)
- Carrie A Schinstock
- Department of Internal Medicine, Division of Nephrology and Hypertension, William J von Liebig Center for Transplantation and Clinical Regeneration, Mayo Clinic, 200 1st Street Southwest, Rochester, MN 55905, USA.
| | - Manish J Gandhi
- Division of Transfusion Medicine, Mayo Clinic, 200 1st Street Southwest, Rochester, MN 55905, USA
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Zotta F, Guzzo I, Morolli F, Diomedi-Camassei F, Dello Strologo L. Protocol biopsies in pediatric renal transplantation: a precious tool for clinical management. Pediatr Nephrol 2018; 33:2167-2175. [PMID: 29980849 DOI: 10.1007/s00467-018-4007-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 06/15/2018] [Accepted: 06/18/2018] [Indexed: 10/28/2022]
Abstract
BACKGROUND Kidney transplantation is the best treatment for children with end-stage kidney disease. Early results have improved, but late graft loss is still a major problem. Non-invasive, fully reliable early biomarkers of acute rejection are currently missing. METHODS Our aim was to evaluate the efficacy of protocol biopsies (PBXs) in a pediatric population. During 11 years, 209 renal transplantations were performed in 204 pediatric patients. Biopsies were performed 3-6 months, 1 year, and 5 years after transplantation. Procedure-related complications were systematically looked for by means of ultrasound scans. RESULTS Unexpected findings (mainly subclinical rejections) requiring therapeutic intervention were found in 19.3% biopsies performed at 3-6 months, in 18.4% in 12-month biopsies and in none of those performed after 5 years. The 13.6% patients at 12-month biopsies and 23.6% at 5-year biopsies showed calcineurin inhibitor (CNI) toxicity. Interstitial fibrosis and tubular atrophy (IF/TA) was found in 17.6 and 83.6% of patients at 12-month and 5-year biopsies, respectively. Complications of the PBX were infrequent. Five-year estimated glomerular filtration rate (GFR) was not significantly different in patients who received treatment for any cause and patients with normal histology. CONCLUSIONS Although we do not have a control group, we may speculate that patients who received treatment returned to a "standard" condition possibly improving final outcome. Protocol biopsies are a powerful diagnostic tool for the management of pediatric renal transplant recipients. In view of the lack of evidence that biopsies taken 5 years after transplantation lead to any therapeutic change, their use should be reconsidered.
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Affiliation(s)
- Federica Zotta
- Renal Transplant Unit, Bambino Gesù Children's Research Hospital IRCCS, Piazza S. Onofrio 4, 00165, Rome, Italy
| | - Isabella Guzzo
- Renal Transplant Unit, Bambino Gesù Children's Research Hospital IRCCS, Piazza S. Onofrio 4, 00165, Rome, Italy
| | - Federica Morolli
- Renal Transplant Unit, Bambino Gesù Children's Research Hospital IRCCS, Piazza S. Onofrio 4, 00165, Rome, Italy
| | | | - Luca Dello Strologo
- Renal Transplant Unit, Bambino Gesù Children's Research Hospital IRCCS, Piazza S. Onofrio 4, 00165, Rome, Italy.
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Utility of MAG3 scintigraphy with the use of a 2 min uptake parameter in the assessment of postsurgical renal transplant complications. Nucl Med Commun 2018; 39:921-927. [DOI: 10.1097/mnm.0000000000000885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Joelsons G, Domenico T, Gonçalves L, Manfro R. Non-invasive messenger RNA transcriptional evaluation in human kidney allograft dysfunction. Braz J Med Biol Res 2018; 51:e6904. [PMID: 29791589 PMCID: PMC5972022 DOI: 10.1590/1414-431x20186904] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 03/19/2018] [Indexed: 11/21/2022] Open
Abstract
The aim of the present study was to evaluate messenger RNA expression in kidney allograft recipients. Forty-four kidney transplant recipients were evaluated up to three months after grafting. After transplantation, peripheral blood samples were drawn sequentially for real-time polymerase chain reaction analyses of perforin and TIM-3 genes. Biopsies were obtained to evaluate acute graft dysfunction and interpreted according to the Banff classification. Eight patients presented episodes of acute rejection. Recipients with rejection had significantly higher levels of TIM-3 mRNA transcripts compared to those without rejection (median gene expression 191.2 and 36.9 mRNA relative units, respectively; P<0.0001). Also, perforin gene expression was higher in patients with rejection (median gene expression 362.0 and 52.8 mRNA relative units; P<0.001). Receiver operating characteristic curves showed that the area under the curve (AUC) for the TIM-3 gene was 0.749 (95%CI: 0.670-0.827). Perforin gene mRNA expression provided an AUC of 0.699 (95%CI: 0.599 to 0.799). Overall accuracy of gene expression was 67.9% for the TIM-3 gene and 63.6% for the perforin gene. Combined accuracy was 76.8%. Negative predictive values were 95.3% for the TIM-3 gene, 95.5% for the perforin gene, and 95.4% in the combined analyses. Gene expression was significantly modulated by rejection treatment decreasing 64.1% (TIM-3) and 90.9% (perforin) compared to the median of pre-rejection samples. In conclusion, the longitudinal approach showed that gene profiling evaluation might be useful in ruling out the diagnosis of acute rejection and perhaps evaluating the efficacy of treatment.
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Affiliation(s)
- G. Joelsons
- Programa de Pós-Graduação em Medicina: Ciências Médicas,
Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre,
RS, Brasil
| | - T. Domenico
- Programa de Pós-Graduação em Medicina: Ciências Médicas,
Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre,
RS, Brasil
| | - L.F. Gonçalves
- Programa de Pós-Graduação em Medicina: Ciências Médicas,
Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre,
RS, Brasil
- Serviço de Nefrologia, Hospital de Clínicas de Porto Alegre,
Porto Alegre, RS, Brasil
| | - R.C. Manfro
- Programa de Pós-Graduação em Medicina: Ciências Médicas,
Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre,
RS, Brasil
- Serviço de Nefrologia, Hospital de Clínicas de Porto Alegre,
Porto Alegre, RS, Brasil
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The utility of surveillance biopsies in pediatric kidney transplantation. Pediatr Nephrol 2018; 33:889-895. [PMID: 29260318 DOI: 10.1007/s00467-017-3864-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 12/02/2017] [Accepted: 12/05/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND Surveillance biopsies (SBs) are performed in some pediatric kidney transplant programs, based on data obtained in earlier immunosuppressive eras that the treatment of subclinical acute rejection results in better graft survival. The benefit of SBs for patients on modern immunosuppression regimens is unclear. We have therefore evaluated the clinical utility of SBs in a population of children receiving a kidney transplant. METHODS We have performed SBs at 3, 6 and 12 months post-transplantation as standard of care at our institution since 2013 in patients on a regimen of rabbit anti-thymocyte globulin, tacrolimus, mycophenolate and rapid steroid taper (RST; steroids maintained in some exceptions). We reviewed pathology reports of 82 SBs from 34 transplants in 34 children for all abnormal findings and adequacy of specimens. Clinical records were reviewed for changes in management resulting from SB findings and for significant procedure complications. RESULTS Of the 82 biopsies, 41 (50%) had abnormal findings separate from fibrosis, including five Banff Grade I rejections, ten borderline rejections, six calcineurin-inhibitor nephrotoxicity, four BK-virus nephropathy, five recurrent disease and three acute pyelonephritis. Moderate or more fibrosis was present in nine of the 82 (11%) biopsies. Management changes due to SB findings occurred in nine cases (11.0%). The proportion of abnormal findings or management changes did not differ between the RST or steroid-based groups. Patients performing clean intermittent catheterization showed inflammatory changes often read as rejection, but were managed differently. Three biopsies were deemed inadequate. No significant complications occurred. CONCLUSIONS A high percentage of the SBs performed under modern immunosuppression showed abnormal findings even when fibrosis was excluded. However, management changes due to the SB findings were less frequent, although they occurred in a clinically meaningful percentage of cases. Complications or inadequate specimens were rare.
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Severova-Andreevska G, Grcevska L, Petrushevska G, Cakalaroski K, Sikole A, Stojceva–Taneva O, Danilovska I, Ivanovski N. The Spectrum of Histopathological Changes in the Renal Allograft - a 12 Months Protocol Biopsy Study. Open Access Maced J Med Sci 2018; 6:606-612. [PMID: 29731924 PMCID: PMC5927487 DOI: 10.3889/oamjms.2018.162] [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: 02/12/2017] [Revised: 03/16/2017] [Accepted: 03/17/2018] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Renal transplantation became a routine and successful medical treatment for Chronic Kidney Disease in the last 30 years all over the world. Introduction of Luminex based Single Antigen Beads (SAB) and recent BANFF consensus of histopathological phenotypes of different forms of rejection enables more precise diagnosis and changes the therapeutic approach. The graft biopsies, protocol or cause, indicated, remain a golden diagnostic tool for clinical follow up of kidney transplant recipients (KTR). AIM The study aimed to analyse the histopathological changes in renal grafts 12 months after the surgery in KTR with satisfactory kidney function. MATERIAL AND METHODS A 12-month protocol biopsy study was performed in a cohort of 50 Kidney transplant recipients (42 from living and 8 from deceased donors). Usual work-up for suitable donors and recipients, standard surgical procedure, basic principles of peri and postoperative care and follow up were done in all KTR. Sequential quadruple immunosuppression including induction with Anti-thymocyte globulin (ATG) or Interleukin-2R antagonist (IL-2R), and triple drug maintenance therapy with Calcineurin Inhibitors (CNI), Mycophenolate Mofetil (MMF) and Steroids were prescribed to all pts. Different forms of Glomerulonephritis (16), Hypertension (10), End Stage Renal Disease (13), Hereditary Nephropathies (6), Diabetes (3) and Vesicoureteral Reflux (2) were the underlying diseases. All biopsies were performed under ultrasound guidance. The 16 gauge needles with automated "gun" were used to take 2 cores of tissue. The samples were stained with HE, PAS, Trichrome Masson and Silver and reviewed by the same pathologist. A revised and uploaded BANFF 2013 classification in 6 categories (Cat) was used. RESULTS Out of 48 biopsies, 15 (31%) were considered as normal, 4 (8%), Borderline (BL-Cat 3), 5 (10%) as Interstitial Fibrosis/Tubular Atrophy (IF/TA-Cat 5), 5 (10%) were classified as non-immunological (Cat 6), 2 as a pure antibody-mediated rejection (ABMR-Cat 2) and T-cell Mediated Rejection (TCMR-Cat 4). The remaining 17 samples were classified as a "mixed" rejection: 7 (41%) ABMR + IF/TA, 5 (29%) ABMR + BL + IF/TA, 2 (11%) BL + IF/TA, 1 (5%) ABMR + BL, 1 (5%) ABMR + TCMR and 1 (5%) TCMR + IF/TA. The mean serum creatinine at the time of the biopsy was 126.7 ± 23.4 µmol/L, while GFR-MDRD 63.4 ± 20.7 ml/min, which means that the majority of the findings were subclinical. Among the non-immunological histological findings (Cat 6), 3 cases belonged to CNI toxicity, 1 to BK nephropathy and 1 to recurrence of the primary disease. CONCLUSION Our 12-month protocol biopsy study revealed the presence of different forms of mixed subclinical rejection. Use of recent BANFF classification and scoring system enables more precise diagnosis and subsequently different approach to the further treatment of the KTR. More correlative long-term studies including Anti HLA antibodies and Endothelial Cell Activation- Associated Transcripts (ENDAT) are needed.
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Affiliation(s)
- Galina Severova-Andreevska
- University Clinic of Nephrology, Medical Faculty, University St Cyril and Methodius of Skopje, Skopje, Republic of Macedonia
| | - Ladislava Grcevska
- University Clinic of Nephrology, Medical Faculty, University St Cyril and Methodius of Skopje, Skopje, Republic of Macedonia
| | - Gordana Petrushevska
- Institute for Pathology, Medical Faculty, University St Cyril and Methodius of Skopje, Skopje, Republic of Macedonia
| | - Koco Cakalaroski
- Medical Faculty, University St Cyril and Methodius of Skopje, Skopje, Republic of Macedonia
| | - Aleksandar Sikole
- University Clinic of Nephrology, Medical Faculty, University St Cyril and Methodius of Skopje, Skopje, Republic of Macedonia
| | - Olivera Stojceva–Taneva
- University Clinic of Nephrology, Medical Faculty, University St Cyril and Methodius of Skopje, Skopje, Republic of Macedonia
| | - Ilina Danilovska
- University Clinic of Nephrology, Medical Faculty, University St Cyril and Methodius of Skopje, Skopje, Republic of Macedonia
| | - Ninoslav Ivanovski
- Medical Faculty, University St Cyril and Methodius of Skopje, Skopje, Republic of Macedonia
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14
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Zhu N, Rowe NE, Martin PR, Luke SS, Mcgregor TB, Myslik F, Mcalister VC, Sener A, Luke PP. Long-term results of protocol kidney biopsy directing steroid withdrawal in simultaneous pancreas-kidney transplant patients. Can Urol Assoc J 2018; 12:188-192. [PMID: 29485032 DOI: 10.5489/cuaj.4702] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
INTRODUCTION We sought to determine whether protocol biopsies could be used to guide treatment and improve outcomes in simultaneous pancreas-kidney (SPK) patients. METHODS Between 2004 and 2013, protocol biopsies were performed on SPK patients at 3-6 months and one year post-transplant. Maintenance immunosuppression consisted of a calcineurin inhibitor, anti-proliferative agent, and corticosteroid. Corticosteroid was withdrawn in negative early biopsies, maintained in subclinical/ borderline biopsies, and increased if Banff IB or greater rejection was identified. Endpoints included presence of interstitial fibrosis and tubular atrophy on biopsy at one year (IF/TA), rejection episodes, and renal and pancreas function at five years' followup. RESULTS Forty-one SPK transplant patients were reviewed and a total of 75 protocol biopsies were identified. On early biopsy, 51% had negative biopsies, 44% had borderline rejection, and 5% had subclinical rejection. Renal and pancreas function were not significantly different at one, two, and five years post-transplant between negative vs. borderline early biopsy patients. No difference in the degree of IF/TA was found between these two groups. CONCLUSIONS To our knowledge, this is the first study to evaluate protocol biopsies as an investigative tool prior to steroid withdrawal in SPK patients. Our study suggests that there are no detrimental functional or histological effects at five years post-transplant, despite weaning steroids in the negative biopsy group.
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Affiliation(s)
- Nemin Zhu
- Western University Schulich School of Medicine and Dentistry, London, ON; Canada
| | - Neal E Rowe
- Department of Surgery, University of Ottawa, Ottawa, ON; Canada
| | - Paul R Martin
- Western University Schulich School of Medicine and Dentistry, London, ON; Canada.,Department of Surgery, London Health Sciences Centre, Western University, London, ON; Canada
| | - Sean S Luke
- Western University Schulich School of Medicine and Dentistry, London, ON; Canada
| | | | - Frank Myslik
- Western University Schulich School of Medicine and Dentistry, London, ON; Canada
| | - Vivian C Mcalister
- Western University Schulich School of Medicine and Dentistry, London, ON; Canada.,Department of Surgery, London Health Sciences Centre, Western University, London, ON; Canada.,Multi-Organ Transplant Program, London Health Sciences Centre, London, ON; Canada
| | - Alp Sener
- Western University Schulich School of Medicine and Dentistry, London, ON; Canada.,Department of Surgery, London Health Sciences Centre, Western University, London, ON; Canada.,Multi-Organ Transplant Program, London Health Sciences Centre, London, ON; Canada
| | - Patrick P Luke
- Western University Schulich School of Medicine and Dentistry, London, ON; Canada.,Department of Surgery, London Health Sciences Centre, Western University, London, ON; Canada.,Multi-Organ Transplant Program, London Health Sciences Centre, London, ON; Canada
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15
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Chow KM, Szeto CC, Lai FMM, Luk CCW, Kwan BCH, Leung CB, Li PKT. Functional and histological improvement after everolimus rescue of chronic allograft dysfunction in renal transplant recipients. Ther Clin Risk Manag 2015; 11:829-35. [PMID: 26056462 PMCID: PMC4445695 DOI: 10.2147/tcrm.s84030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Background We tested the strategy of mTOR inhibitors with calcineurin inhibitor minimization in renal transplant recipients with known chronic allograft dysfunction. Methods In this open-label, single-arm study, renal transplant patients were recruited after biopsy-confirmed chronic allograft dysfunction in the absence of acute rejection episode within 2 months, with proteinuria <0.8 g/day, and serum creatinine <220 μmol/L or estimated glomerular filtration rate >40 mL/min/1.73 m2. They were converted to everolimus (aiming for trough everolimus level 3–8 ng/mL) with cyclosporine minimization, to assess the effect on renal function, rate of glomerular filtration rate decline, and longitudinal transplant biopsy at 12 months. Results Seventeen Chinese patients (median transplant duration, 4.2 years) were recruited; no patients discontinued study medication. The mean slope of the glomerular filtration rate over time was −4.31±6.65 mL/min/1.73 m2 per year in the year before everolimus, as compared with 1.29±5.84 mL/min/1.73 m2 per year in the 12 months of everolimus therapy, a difference of 5.61 mL/min/1.73 m2 per year (95% confidence interval [CI], 0.40–10.8) favoring everolimus therapy (P=0.036). Serial renal biopsy histology showed significant decrease of tubular atrophy (15.7%±11.3% versus 7.1%±7.3%, P=0.005) and interstitial fibrosis (14.8%±11.5% versus 7.2%±8.2%, P=0.013). Intrarenal expression of TGF-β1 mRNA showed a nonsignificant decrease after everolimus treatment. Conclusion In renal transplant recipients with biopsy-confirmed chronic allograft dysfunction, we found a significant beneficial effect of everolimus rescue therapy and calcineurin inhibitor minimization strategy on the improvement of glomerular filtration rate decline rate. In secondary analysis, everolimus was shown to slow down the disease progression by reducing the tubular atrophy and interstitial fibrosis scoring.
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Affiliation(s)
- Kai Ming Chow
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - Cheuk Chun Szeto
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - Fernand Mac-Moune Lai
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - Cathy Choi-Wan Luk
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - Bonnie Ching-Ha Kwan
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - Chi Bon Leung
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - Philip Kam-Tao Li
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
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16
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Tanabe T. The value of long-term protocol biopsies after kidney transplantation. Nephrology (Carlton) 2015; 19 Suppl 3:2-5. [PMID: 24842813 DOI: 10.1111/nep.12253] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2014] [Indexed: 01/04/2023]
Abstract
Protocol biopsies for the detection and treatment of subclinical rejection in the early period after kidney transplantation are useful for preventing allograft dysfunction. However, little has been reported on the relationship between subclinical rejection and long-term protocol biopsies. In this review, we examine the potential benefits associated with long-term allograft biopsies focusing on the issue of immunological and non-immunological factors. Early detection and treatment of subclinical rejection improves outcome. However, the benefit of long-term allograft biopsies is largely unproved, and the strategy is yet to be widely implemented. The procurement of long-term protocol biopsies for the sole purpose of detecting subclinical rejection may be unwarranted. On the other hand, the early detection of IgA nephropathy using long-term protocol biopsy may improve graft survival. In addition, assessment of long-term protocol biopsies is useful not only for detection of calcineurin inhibitor nephrotoxicity, but also for follow-up after withdrawal of calcineurin inhibitor regimens. Also, identifying normal histology on a protocol biopsy may inform us about the safety of reducing overall immunosuppression. Thus, the potential benefit of long-term protocol biopsy may be of clinical significance for the detection of graft dysfunction as a result of non-immune factors, such as recurrence of glomerulonephritis and calcineurin inhibitor nephrotoxicity, rather than subclinical rejection.
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Affiliation(s)
- Tatsu Tanabe
- Department of Urology, Hokkaido University Hospital, Sapporo, Japan
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17
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Mehrotra A, Leventhal J, Purroy C, Cravedi P. Monitoring T cell alloreactivity. Transplant Rev (Orlando) 2014; 29:53-9. [PMID: 25475045 DOI: 10.1016/j.trre.2014.11.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 10/03/2014] [Accepted: 11/09/2014] [Indexed: 01/06/2023]
Abstract
Currently, immunosuppressive therapy in kidney transplant recipients is center-specific, protocol-driven, and adjusted according to functional or histological evaluation of the allograft and/or signs of drug toxicity or infection. As a result, a large fraction of patients receive too much or too little immunosuppression, exposing them to higher rates of infection, malignancy and drug toxicity, or increased risk of acute and chronic graft injury from rejection, respectively. The individualization of immunosuppression requires the development of assays able to reliably quantify and/or predict the magnitude of the recipient's immune response toward the allograft. As alloreactive T cells are central mediators of allograft rejection, monitoring T cell alloreactivity has become a priority for the transplant community. Among available assays, flow cytometry based phenotyping, T cell proliferation, T cell cytokine secretion, and ATP release (ImmuKnow), have been the most thoroughly tested. While numerous cross-sectional studies have found associations between the results of these assays and the presence of clinically relevant post-transplantation outcomes, data from prospective studies are still scanty, thereby preventing widespread implementation in the clinic. Future studies are required to test the hypothesis that tailoring immunosuppression on the basis of results offered by these biomarkers leads to better outcomes than current standard clinical practice.
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Affiliation(s)
- Anita Mehrotra
- Renal Division, Department of Medicine, Icahn School of Medicine at Mount Sinai, NY, USA
| | - Jeremy Leventhal
- Renal Division, Department of Medicine, Icahn School of Medicine at Mount Sinai, NY, USA
| | - Carolina Purroy
- Renal Division, Department of Medicine, Icahn School of Medicine at Mount Sinai, NY, USA
| | - Paolo Cravedi
- Renal Division, Department of Medicine, Icahn School of Medicine at Mount Sinai, NY, USA.
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18
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Orlacchio A, Chegai F, Del Giudice C, Anselmo A, Iaria G, Palmieri G, Di Caprera E, Tosti D, Costanzo E, Tisone G, Simonetti G. Kidney transplant: usefulness of real-time elastography (RTE) in the diagnosis of graft interstitial fibrosis. ULTRASOUND IN MEDICINE & BIOLOGY 2014; 40:2564-72. [PMID: 25218454 DOI: 10.1016/j.ultrasmedbio.2014.06.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 05/11/2014] [Accepted: 06/03/2014] [Indexed: 05/24/2023]
Abstract
The aim of this study is to evaluate the usefulness of real-time elastography (RTE) in the diagnosis of graft interstitial fibrosis. We prospectively enrolled 50 patients clinically suspected of graft fibrosis. RTE was performed with a broadband linear transducer using a dedicated ultrasound machine. Tissue mean elasticity (TME) was calculated by two blinded operators. All patients underwent biopsy after RTE. To determine cortical fibrosis Banff score was used. The receiver operating characteristic curves analysis was performed to evaluate the accuracy of TME to discriminate between patients with mild fibrosis (F1) versus patients with moderate to severe fibrosis (F2-F3). Inverse correlation between TME values and the degree of fibrosis has been shown (p < 0.05). Patients with F1 had mean TME values significantly higher compared with TME in patients with F2 (p = 0.005) and F3 (p = 0.004). The diagnostic accuracy of TME measurement for F2-F3 evaluated by area under the curve-receiver operating characteristic analysis was 0.95. RTE was able to evaluate kidney fibrosis in a non-invasive way and could be used as complementary imaging during follow-up of renal transplant patients.
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Affiliation(s)
- Antonio Orlacchio
- Department of Diagnostic and Molecular Imaging, Radiation Therapy and Interventional Radiology, University Hospital Tor Vergata, Rome, Italy; Organ Transplantation Unit, University Hospital Tor Vergata, Rome, Italy.
| | - Fabrizio Chegai
- Department of Diagnostic and Molecular Imaging, Radiation Therapy and Interventional Radiology, University Hospital Tor Vergata, Rome, Italy
| | - Costantino Del Giudice
- Department of Diagnostic and Molecular Imaging, Radiation Therapy and Interventional Radiology, University Hospital Tor Vergata, Rome, Italy
| | - Alessandro Anselmo
- Organ Transplantation Unit, University Hospital Tor Vergata, Rome, Italy
| | - Giuseppe Iaria
- Organ Transplantation Unit, University Hospital Tor Vergata, Rome, Italy
| | - Giampiero Palmieri
- Institute of Anatomic Pathology, University Hospital Tor Vergata, Rome, Italy
| | - Elena Di Caprera
- Department of Diagnostic and Molecular Imaging, Radiation Therapy and Interventional Radiology, University Hospital Tor Vergata, Rome, Italy
| | - Daniela Tosti
- Department of Diagnostic and Molecular Imaging, Radiation Therapy and Interventional Radiology, University Hospital Tor Vergata, Rome, Italy
| | - Elisa Costanzo
- Department of Diagnostic and Molecular Imaging, Radiation Therapy and Interventional Radiology, University Hospital Tor Vergata, Rome, Italy
| | - Giuseppe Tisone
- Organ Transplantation Unit, University Hospital Tor Vergata, Rome, Italy
| | - Giovanni Simonetti
- Department of Diagnostic and Molecular Imaging, Radiation Therapy and Interventional Radiology, University Hospital Tor Vergata, Rome, Italy
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19
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Limited efficacy of immunosuppressive drugs on CD8+ T cell-mediated and natural killer cell-mediated lysis of human renal tubular epithelial cells. Transplantation 2014; 97:1110-8. [PMID: 24704664 DOI: 10.1097/tp.0000000000000108] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Although CD8+ T cell-mediated and natural killer (NK) cell-mediated cytotoxicity against renal tubular epithelial cells (TECs) plays a crucial role during rejection, the degree of inhibition of these lytic immune responses by immunosuppressive drugs is unknown. We investigated the CD8 T-cell and NK cell responses induced by TECs in vitro and questioned how these processes are affected by immunosuppressive drugs. METHODS Donor-derived TECs were co-cultured with recipient peripheral blood monocyte cells. Proliferation of CD8+ T cells and NK cell subsets was assessed using PKH dilution assay. CD107a degranulation and europium release assay were performed to explore CD8+-mediated and NK cell-mediated TEC lysis. Experiments were conducted in the absence or presence of tacrolimus (10 ng/mL), everolimus (10 ng/mL), and prednisolone (200 ng/mL). RESULTS Tubular epithelial cells induce significant CD8+ T-cell and NK cell proliferation. All immunosuppressive drugs significantly inhibited TEC-induced CD8+ T-cell proliferation. Interestingly, prednisolone was the most powerful inhibitor of NK cell proliferation. CD8-mediated and NK cell-mediated early lytic responses were marked by strong degranulation after an encounter of unstimulated TECs, represented by a high cell surface expression of CD107a. However, with the use of interferon-γ-activated and tumor necrosis factor-α-activated TECs, the NK degranulation response was significantly reduced and CD8 degranulation response was even more enhanced (P<0.05). Tubular epithelial cell-induced CD8 degranulation and CD8-mediated TEC lysis were preferentially inhibited by tacrolimus and prednisolone, and not by everolimus. Although tacrolimus showed the most inhibitory effect on the degranulation of NK cells, NK cell-mediated TEC lysis was efficiently inhibited by prednisolone (P<0.05). CONCLUSION Overall, our data point to a limited efficacy of immunosuppressive drugs on CD8+ T cell-mediated and NK cell-mediated lysis of human renal TECs.
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20
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Cravedi P, Mannon RB. Noninvasive methods to assess the risk of kidney transplant rejection. Expert Rev Clin Immunol 2014; 5:535-546. [PMID: 20161000 DOI: 10.1586/eci.09.36] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In current clinical practice, immune reactivity of kidney transplant recipients is estimated by monitoring the levels of immunosuppressive drugs, and by functional and/or histological evaluation of the allograft. The availability of assays that could directly quantify the extent of the recipient's immune response towards the allograft would help clinicians to customize the prescription of immunosuppressive drugs to individual patients. Importantly, these assays might provide a more in-depth understanding of the complex mechanisms of acute rejection, chronic injury, and tolerance in organ transplantation, allowing the design of new and potentially more effective strategies for the minimization of immunosuppression, or even for the induction of immunological tolerance. The purpose of this review is to summarize results from recent studies in this field.
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Affiliation(s)
- Paolo Cravedi
- Mario Negri Institute for Pharmacological Research, Bergamo, Italy, Tel.: +39 035 453 5405, ,
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21
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Guleria S, Jain S, Dinda AK, Mahajan S, Gupta S, Mehra NK. The short-term impact of protocol biopsies in a live-related renal transplant program using tacrolimus based immunosuppression. Indian J Nephrol 2013; 23:253-8. [PMID: 23960339 PMCID: PMC3741967 DOI: 10.4103/0971-4065.114474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
The aim of the study was to assess the impact of protocol biopsies in a live-related renal transplant program using tacrolimus-based immunosuppression in the short term. Eighty-three live-related transplant recipients were randomly allocated to protocol biopsy group (Group I, n = 40) and a control group (Group II, n = 43). Other immunosuppressants in these groups consisted of either mycophenolate mofetil or azathioprine and steroids. Protocol biopsies were conducted in biopsy group at 1, 6, and 12 months post-transplant. The non-biopsy group was followed by serial serum creatinine and biopsies in them were conducted as and when clinically indicated. Both groups were analyzed at 12 months with respect to graft function and survival. The two groups were similar with respect to age, number of dialysis pre-operatively, tacrolimus levels, induction therapy, donor age, and donor glomerular filtration rate. Forty protocol biopsies were conducted at 1 month, 31 at 6 months, and 26 at 12 months. The prevalence of sub-clinical rejection at 1, 6, and 12 months in these biopsies was 17.5%, 11.2%, and 10.3%, respectively. The prevalence of calcineurin inhibitor toxicity during same period was 15%, 15.5%, and 14.4%, respectively. The cumulative rejection rate in Group I and Group II at 12-month follow-up was 10.3% and 11.3% (P = 0.78), respectively, and cumulative calcineurin inhibitor toxicity at 12 months was 14.4% and 9.3% (P = 0.59), respectively, were not statistically significant. There was no difference in graft survival and function at 1 year. Protocol biopsies have a limited role in a well-matched renal transplant program with tacrolimus-based immunosuppression in the short term. However, the long-term impact of protocol biopsies needs further evaluation.
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Affiliation(s)
- S Guleria
- Department of Surgery, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India
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22
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Grabner A, Kentrup D, Edemir B, Sirin Y, Pavenstädt H, Schlatter E, Schober O, Schäfers M, Schnöckel U, Reuter S. PET with 18F-FDG-labeled T lymphocytes for diagnosis of acute rat renal allograft rejection. J Nucl Med 2013; 54:1147-53. [PMID: 23670903 DOI: 10.2967/jnumed.112.109231] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
UNLABELLED We proposed small-animal PET with (18)F-FDG-labeled T lymphocytes as a new method for image-based diagnosis of acute allogeneic renal transplant rejection (AR) established in a rat model. METHODS One and 2 h after tail vein injection of 30 × 10(6) ex vivo (18)F-FDG-labeled human T cells into male 10-wk-old uninephrectomized, allogeneically transplanted rats (aTX; Lewis-brown Norway [LBN] to Lewis), whole-body radioactivity distribution was assessed in vivo by small-animal PET (postoperative day 4), and percentage injected dose (%ID) as a parameter of T-cell infiltration was assessed and compared between graft and native kidney. In vivo results were confirmed by autoradiography and staining of human CD3 after postmortem dissection. Syngeneically transplanted rats (sTX) (LBN to LBN), rats with ischemia-reperfusion injury (IRI) (45-min warm ischemia), and rats subjected to acute cyclosporine A (CSA) toxicity (50 mg/kg for 2 d intraperitoneally) served as controls. RESULTS The accumulation of labeled cells was significantly elevated in allografts with AR (1.07 ± 0.28 %ID), compared with native control kidneys (0.49 ± 0.18 %ID) (P < 0.0001). No differences were found among native controls, sTX, CSA toxicity, and kidneys with IRI. In vivo uptake of (18)F-FDG cells measured in the PET scanner correlated with results obtained by autoradiography, histologic evaluation, and polymerase chain reaction. CONCLUSION We proposed graft PET imaging using (18)F-FDG-labeled T cells as a new option to detect rat renal AR with a low dose of (18)F-FDG in a noninvasive, fast, and specific manner in rats.
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Affiliation(s)
- Alexander Grabner
- Department of Internal Medicine D, Experimental Nephrology, University of Münster, Münster, Germany
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Hirt-Minkowski P, Amico P, Ho J, Gao A, Bestland J, Hopfer H, Steiger J, Dickenmann M, Burkhalter F, Rush D, Nickerson P, Schaub S. Detection of clinical and subclinical tubulo-interstitial inflammation by the urinary CXCL10 chemokine in a real-life setting. Am J Transplant 2012; 12:1811-23. [PMID: 22390571 DOI: 10.1111/j.1600-6143.2012.03999.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Urinary CXCL10 is a promising noninvasive biomarker for tubulo-interstitial allograft inflammation, but its diagnostic characteristics have not been assessed in a real-life setting. We investigated urinary CXCL10 in 213 consecutive renal allograft recipients having 362 surveillance biopsies at 3/6 months and 80 indication biopsies within the first year posttransplant. Allograft histology results were classified as (i) acute Banff score zero, (ii) interstitial infiltrates only, (iii) tubulitis t1, (iv) tubulitis t2-3 and (v) isolated vascular compartment inflammation. For clinical and subclinical pathologies, urinary CXCL10 correlated well with the extent of tubulo-interstitial inflammation. To determine diagnostic characteristics of urinary CXCL10, histological groups were separated into two categories: no relevant inflammation (i.e. acute Banff score zero and interstitial infiltrates only) versus all other pathologies (i.e. tubulitis t1-3 and isolated vascular compartment inflammation). For subclinical pathologies, AUC was 0.69 (sensitivity 61%, specificity 72%); for clinical pathologies, AUC was 0.74 (sensitivity 63%, specificity 80%). A urinary CXCL10-guided biopsy strategy would have reduced performance of surveillance and indication biopsies by 61% and 64%, respectively. Missed (sub)clinical pathologies were mostly tubulitis t1 and isolated vascular compartment lesions. In real life, urinary CXCL10 had clinically useful diagnostic properties making it a candidate biomarker to guide allograft biopsies.
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Affiliation(s)
- P Hirt-Minkowski
- Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
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Surveillance biopsies in children post-kidney transplant. Pediatr Nephrol 2012; 27:753-60. [PMID: 21792611 PMCID: PMC3315641 DOI: 10.1007/s00467-011-1969-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 06/29/2011] [Accepted: 07/05/2011] [Indexed: 01/05/2023]
Abstract
Surveillance biopsies are increasingly used in the post-transplant monitoring of pediatric renal allograft recipients. The main justification for this procedure is to diagnose early and presumably modifiable acute and chronic renal allograft injury. Pediatric recipients are theoretically at increased risk for subclinical renal allograft injury due to their relatively large adult-sized kidneys and their higher degree of immunological responsiveness. The safety profile of this procedure has been well investigated. Patient morbidity is low, with macroscopic hematuria being the most common adverse event. No patient deaths have been attributed to this procedure. Longitudinal surveillance biopsy studies have revealed a substantial burden of subclinical immunological and non-immunological injury, including acute cellular rejection, interstitial fibrosis and tubular atrophy, microvascular lesions and transplant glomerulopathy. The main impediment to the implementation of surveillance biopsies as the standard of care is the lack of demonstrable benefit of early histological detection on long-term outcome. The considerable debate surrounding this issue highlights the need for multicenter, prospective, and randomized studies.
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Krejčí K, Tichý T, Al-Gabri S, Horák P, Ciferská H, Hrubý M, Horčička V, Strebl P, Zamboch K, Bachleda P, Zadrazil J. Protocol biopsy of a transplanted kidney as a tool for monitoring adequacy of immunosuppressive therapy: 10 years of experience from a single transplant center. Transplant Proc 2011; 43:1576-82. [PMID: 21693237 DOI: 10.1016/j.transproceed.2011.03.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Revised: 02/11/2011] [Accepted: 03/01/2011] [Indexed: 10/18/2022]
Abstract
BACKGROUND The aims of this prospective study were to determine the prevalence of clinically silent rejection changes and of nephrotoxicity of calcineurin inhibitors among repeated protocol biopsies of transplanted kidneys and to assess their impacts on chronic graft function and damage at the end of 1 year. METHODS We performed 424 protocol biopsies among 158 patients over the first year after transplantation. We monitored parameters of graft function and progression of chronic changes among subjects with clinically silent rejection or toxicity for comparison with a control cohort showing normal histological findings. The results of statistical tests were considered to be significant at a level of P < .05. RESULTS At 3 weeks, 3 months, and 12 months, there were normal histological findings among 30 (19%), 21 (14.8%), and 14 (11.3%) patients, respectively; subclinical rejection changes occurred in 49 (31%), 36 (25.4%), and 20 (16.2%) grafts, respectively. At the third week, histological signs of toxicity occurred in 33 (20.9%) patients with significant persistence despite reductions in calcineurin inhibitor doses. At the end of 1 year of follow-up, both subclinical and toxic changes produced similar increases in chronic changes as quantified by the Banff score and were significantly different from the control group (P < .05). Serum creatinine concentrations and glomerular filtration rates did not accurately reflect the degree of graft damage in the early posttransplantation period. CONCLUSIONS Subclinical rejection and toxic changes among a significant proportion of grafts are associated with progression of chronic changes already over the first year following transplantation. Hence they represent independent risk factors for the development of irreversible graft damage. Protocol biopsy seems to be an important method to monitor immunosuppressive therapy.
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Affiliation(s)
- K Krejčí
- 3rd Department of Internal Medicine and Nephrology, University Hospital Olomouc, Olomouc, Czech Republic.
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Szederkényi E, Iványi B, Morvay Z, Szenohradszki P, Borda B, Marofka F, Kemény E, Lázár G. Treatment of subclinical injuries detected by protocol biopsy improves the long-term kidney allograft function: a single center prospective randomized clinical trial. Transplant Proc 2011; 43:1239-43. [PMID: 21620099 DOI: 10.1016/j.transproceed.2011.03.078] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND The long-term benefit of early treatment of subclinical disorders detected in kidney allografts by protocol biopsy is controversial. We collected 145 protocol biopsies from 113 recipients for comparison with 51 control patients in a single-center, prospective, randomized trial. METHODS Ultrasound-guided biopsies were performed in recipients with stable renal function. Samples were taken at 3 (n=66) and/or 12 months (n=79) after transplantation. The biopsies were evaluated according to the Banff scheme, and patients were treated based on the diagnosis. Changes in glomerular filtration rate (GFR) were compared with 51 patients who were randomized as a control group. RESULTS The findings on 38 samples (29%) were considered to be normal. Based on the pathology findings, such as subclinical acute rejection (n=23), calcineurin inhibitor toxicity (n=28), chronic rejection (n=6), and other specific pathologies (n=23), including polyoma virus nephropathy (n=2), induced treatment among 82 recipients (57%). Significantly better graft function was observed at 3-year follow-up among the biopsy group, compared with controls: GFR = 46.0 ± 13.8 vs 35 ± 15 mL/min (P=.002). The 5-year graft survival was significantly higher in the biopsy (81%) than in the control (55.6%) group (P=.0012). CONCLUSION Early detection and treatment of subclinical pathologies improved graft function and long-term survival. Protocol biopsies were a valuable tool for posttransplantation management.
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Affiliation(s)
- E Szederkényi
- Department of Clinical Surgery, Albert Szent-Györgyi Clinical Center, Faculty of Medicine, University of Szeged, Szeged, Hungary.
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Baker R, Jardine A, Andrews P. Renal Association Clinical Practice Guideline on post-operative care of the kidney transplant recipient. Nephron Clin Pract 2011; 118 Suppl 1:c311-47. [PMID: 21555902 DOI: 10.1159/000328074] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Accepted: 02/05/2011] [Indexed: 11/19/2022] Open
Affiliation(s)
- R Baker
- Renal Unit, Lincoln Wing, St. James's University Hospital, Beckett Street, Leeds.
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Abstract
Calcineurin inhibitor (CNI) nephrotoxicity was recognized in Cambridge in the late 1970s. The vasoconstrictor impact of cyclosporine (CsA) and to a lesser extent tacrolimus, in both acute and chronic settings, results from a decrease in vasodilators and increase in vasconconstrictors while direct tubular toxicity results from blockade of mitochondrial permeability transition pores and inhibition of prolyl isomerase. A biopsy of native kidneys of recipients of CNIs reveals nephrotoxicity as the most common pathological diagnosis with chronic CNI toxicity and hypertension the primary problems. A long-term study of randomized clinical trials with up to 20 years of follow-up shows inferiority of both renal function and graft survival for continuous CsA compared to either CsA withdrawal or continuous azathioprine and prednisolone. Pathological hallmarks of chronic CNI nephrotoxicity include stripped interstitial fibrosis, arteriolar hyalinosis and glomerular sclerosis, but with the exception of nodular arteriolar hyalinosis the findings are non specific. The model for chronic renal allograft loss must be multifactorial with both immune and nonimmune factors operating dependent upon an individual's risk factors for cell and/or antibody-mediated rejection, CNI nephrotoxicity and recurrent disease. Better outcomes will require early diagnosis and individualization of therapy dependent upon the dominant mechanisms impacting each patient. The revisionist view put forward by some senior, experienced and thoughtful individuals, challenges the concept of chronic CNI nephrotoxicity as an important clinical entity. By implication, the view that appears to be promoted is as follows: we need not fear-prolonged exposure to CNIs, and in seeking better long-term solutions for transplant recipients, we have forgotten alloimmunity. It is thus apparent that we must revisit the data and again question the basis for chronic CNI nephrotoxicity in current clinical practice. This contribution to the debate will focus on the evidence that CNIs are nephrotoxic and that their impact needs to be limited if we are to improve long-term outcomes after transplantation, leaving others to promote the contrary perspective and perhaps also to reflect on the largely unproven impact of the steroid avoidance and other minimization strategies so prevalent today.
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Affiliation(s)
- J R Chapman
- Centre for Transplant and Renal Research, University of Sydney, Westmead Hospital, Westmead, NSW, Australia.
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Zhang L, Kolokythas O, Dighe M, Kim JH, Leca N, Kim Y. Two-dimensional flow index mapping for hemodynamic imaging: a feasibility study. ULTRASOUND IN MEDICINE & BIOLOGY 2010; 36:2011-2017. [PMID: 21030136 DOI: 10.1016/j.ultrasmedbio.2010.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 08/05/2010] [Accepted: 09/03/2010] [Indexed: 05/30/2023]
Abstract
The resistive index (RI) is a functional hemodynamic index used to measure flow resistance within an organ, such as the kidney, to assess if there is any vascular disease associated with that organ. Currently, the measurement of RI values using spectral Doppler ultrasound (US) is performed in one location at a time. As a result, RI values are typically obtained only from a few locations. To visualize the entire two-dimensional distribution of RI values, we developed a method called two-dimensional flow index mapping (2D-FIM). To evaluate this method, we performed a feasibility study using 16 kidney data sets, with eight from healthy volunteers with normal native kidneys and eight from kidney transplant recipients. Quadrature-demodulated baseband Doppler data were used to calculate the spatial distribution of RI values using 2D-FIM. For comparison, the intrarenal RI values at different levels of renal arterial branches were measured with conventional spectral Doppler US. The RI values determined from 2D-FIM were compared with those from spectral Doppler US, which led to a Pearson correlation coefficient of 0.84. There was no significant difference between 2D-FIM- and spectral Doppler US-produced RI values. With the ability to visualize RI in more than one dimension, 2D-FIM could help guide placement of the spectral Doppler range gate to regions of abnormal RI, thus potentially reducing exam times.
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Affiliation(s)
- Liang Zhang
- Image Computing Systems Laboratory, Department of Bioengineering, University of Washington, Seattle, WA 98195-5061, USA
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Reuter S, Schnöckel U, Edemir B, Schröter R, Kentrup D, Pavenstädt H, Schober O, Schlatter E, Gabriëls G, Schäfers M. Potential of noninvasive serial assessment of acute renal allograft rejection by 18F-FDG PET to monitor treatment efficiency. J Nucl Med 2010; 51:1644-52. [PMID: 20847180 DOI: 10.2967/jnumed.110.078550] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
UNLABELLED We propose (18)F-FDG PET as a method to monitor acute rejection of allogeneic renal transplants in a rat model. METHODS Allogeneically transplanted (aTX) rats (binephrectomized Lewis-brown Norway to Lewis) served as the renal transplant model. aTX rats treated with cyclosporine A (CSA) served as a therapy monitoring group. Healthy control rats, rats with acute CSA nephrotoxicity, rats with acute tubular necrosis, syngeneically transplanted (sTX) rats, and aTX rats treated with CSA since postoperative day 0 served as controls. After surgery, renal glucose metabolism was assessed in vivo serially up to postoperative day 7 by performing small-animal PET 3 h after intravenous injection of 30 MBq of (18)F-FDG. Mean radioactivity (cps/mm(3) of tissue) was measured and the percentage injected dose calculated. Results were confirmed by histologic, functional, and autoradiographic analysis. RESULTS Renal (18)F-FDG uptake was significantly elevated at postoperative day 4 in aTX rats, when compared with control, sTX, acute tubular necrosis, or CSA-treated rats (P < 0.05). In vivo (18)F-FDG uptake correlated with the results of autoradiography and with inflammatory infiltrates observed on histologic examination. Notably, (18)F-FDG PET assessed the response to therapy 48 h earlier than the time at which serum creatinine decreased and when histologic examination still showed signs of allograft rejection. In aTX rats, the CSA-susceptible graft infiltrate was dominated by activated cytotoxic T cells and monocytes/macrophages. CONCLUSION (18)F-FDG PET is an option to noninvasively assess early response to therapy in rat renal allograft rejection.
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Affiliation(s)
- Stefan Reuter
- Department of Medicine D, Experimental Nephrology, University of Münster, Münster, Germany.
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Böhmig GA, Wahrmann M, Säemann MD. Detecting adaptive immunity: applications in transplantation monitoring. Mol Diagn Ther 2010; 14:1-11. [PMID: 20121285 DOI: 10.1007/bf03256348] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In recent decades, continuous improvements in immunosuppressive therapy have led to a significant increase in kidney allograft survival. Despite innovative developments and improvements in immunosuppression, chronic allograft injury and late graft loss still remain major causes of morbidity and mortality. In clinical practice, long-term immunosuppression is adapted and fine-tuned according to drug levels, kidney function, and biopsy results. As an invasive procedure, indication biopsy still represents an indispensible diagnostic gold standard. However, in an effort to further improve outcomes on the basis of individualized treatment, there is an urgent need for noninvasive assays, as well as biomarkers, to more accurately monitor allogeneic responses and predict the risk of acute and chronic allograft rejection. This article discusses strategies for immune monitoring of T-cell responsiveness and humoral alloreactivity. Furthermore, new microarray and gene profiling data are highlighted, which may identify hyporesponsive transplant recipients who could benefit from a reduction or even withdrawal of immunosuppression. Finally, supplementary transplant risk assessment markers, such as soluble CD30 and urinary effector molecule analysis, are discussed as promising new tools. Recent developments and improvements in test principles to monitor and predict allograft immunity are encouraging and may herald the transition of present empiric immunosuppression to individualized immunosuppressive treatment. Nonetheless, before implementation of immune monitoring in routine clinical practice, there is still a need for prospective trials designed to clarify the actual diagnostic potential of individual test systems in a therapeutic context.
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Affiliation(s)
- Georg A Böhmig
- Division of Nephrology and Dialysis, Department of Medicine III, Medical University of Vienna, Vienna, Austria.
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Höcker B, Tönshoff B. Treatment strategies to minimize or prevent chronic allograft dysfunction in pediatric renal transplant recipients: an overview. Paediatr Drugs 2010; 11:381-96. [PMID: 19877724 DOI: 10.2165/11316100-000000000-00000] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Long-term allograft survival poses a major problem in pediatric renal transplantation, with allograft nephropathy being the principal cause of graft failure after the first post-transplant year. The mechanisms of nephron loss resulting in graft dysfunction are multiple, comprising both immunologic factors such as acute and chronic antibody- or T-cell-mediated rejection and non-immunologic components. The latter include peri-transplant injuries and renovascular lesions (renal artery stenosis, thrombosis) as well as cardiovascular risk factors such as arterial hypertension and hyperlipidemia. Another relevant issue leading to progressive nephron loss and declining kidney transplant function is acute and chronic nephrotoxicity induced by the calcineurin inhibitors (CNIs) ciclosporin (cyclosporine microemulsion) and tacrolimus. Furthermore, the presence of an abnormal lower urinary tract as well as bacterial (recurrent pyelonephritis) and viral (cytomegalovirus [CMV], polyomavirus [BK virus; BKV]) infections are crucial factors involved in the incidence of chronic allograft dysfunction and graft failure. Renovascular lesions and lower urinary tract obstruction are typical indicators for surgical intervention. The aim of treatment in pediatric patients with renal failure secondary to a dysfunctional lower urinary tract is to create a sterile, continent, and nonrefluxive reservoir. Surgical techniques such as bladder augmentation and the introduction of intermittent catheterization and anticholinergic therapy have significantly improved graft outcome. Arterial hypertension, another factor responsible for graft function deterioration in pediatric renal transplant recipients, is controlled preferably by the use of angiotensin converting enzyme (ACE) inhibitors or angiotensin II receptor antagonists, which are known to possess nephroprotective properties in addition to their potent antihypertensive effects. Although treatment of subclinical rejection with augmented immunosuppression has been associated with better graft survival, an increase of the immunosuppressive level to avoid subclinical rejection should be weighed against the risk of infection. The majority of viral infections affecting kidney allografts are caused by CMV and BKV. Antiviral CMV prophylaxis or pre-emptive therapy with ganciclovir has been shown to have beneficial effects in the pediatric renal transplant population. Treatment of BKV-induced nephropathy is based on reduction of the immunosuppressant therapy, although specific antiviral agents such as cidofovir and leflunomide are known to inhibit BKV. However, cidofovir itself is nephrotoxic and should therefore be administered cautiously to pediatric renal transplant patients. Since CNIs are likewise known for their nephrotoxic effects, especially with long-term use, alteration of the immunosuppressant regimen is necessary in case of deteriorating graft function due to CNI-induced histopathologic changes. Complete CNI avoidance seems inappropriate because, in this situation in pediatric renal transplant recipients, other relatively potent immunosuppressant agents such as lymphocyte-depleting antibodies, which are frequently accompanied by a higher incidence of infections, are needed for rejection prophylaxis. CNI withdrawal and switching of the immunosuppressant regimen from CNI therapy to sirolimus may be an option for some pediatric renal transplant patients with less advanced graft function deterioration. Nevertheless, potential adverse events such as aggravation of proteinuria, hyperlipidemia, myelosuppression, and hypergonadotropic hypogonadism have to be considered, and controlled studies are lacking. At present, an immunosuppressant maintenance therapy composed of low-dose tacrolimus or ciclosporin (CNI minimization) and mycophenolate mofetil with low-dose corticosteroids appears to be the most promising strategy to adopt in pediatric renal transplant recipients at low or normal immunologic risk.
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Affiliation(s)
- Britta Höcker
- University Children's Hospital, Im Neuenheimer Feld 430, D-69120 Heidelberg, Germany.
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Krejcí K, Tichý T, Hrubý M, Horák P, Ciferská H, Horcicka V, Strebl P, Al-Jabry S, Bachleda P, Zadrazil J. Subclinical toxicity of calcineurin inhibitors in repeated protocol biopsies: an independent risk factor for chronic kidney allograft damage. Transpl Int 2009; 23:364-73. [PMID: 19906031 PMCID: PMC2860761 DOI: 10.1111/j.1432-2277.2009.00995.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The purpose of the prospective study was to determine the prevalence of subclinical toxicity of calcineurin inhibitors (CI) in repeated protocol renal allograft biopsies and to assess its impact on the development of chronic graft changes. A total of 424 biopsies were conducted in a cohort of 158 patients; of these biopsies, 158 were in the third week, 142 were in the third month and 124 were in the first year after transplantation. Histological signs of toxicity occurred in the third week in 33 (20.1%) patients, with persistence after CI dose reduction in the third month in 27 (19.0%) and in the first year in 23 (18.5%) patients. Of the toxic changes, 52% were clinically silent. At the end of the one-year follow-up, both subclinical and clinically manifest toxicity resulted in a similar progression of chronic changes quantified by Banff chronicity score and they significantly differed from the control group (P< 0.05). Subclinical toxicity affects a significant percentage of grafts; it occurs independently of dosage, blood level and type of applied CI. It is associated with the progression of chronic changes as early as in the first year after transplantation and represents an independent risk factor for chronic allograft damage. We report here our clinical approach to toxicity.
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Affiliation(s)
- Karel Krejcí
- 3rd Department of Internal Medicine and Nephrology, University Hospital Olomouc, Olomouc, Czech Republic.
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35
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Nickerson P. Post-transplant monitoring of renal allografts: are we there yet? Curr Opin Immunol 2009; 21:563-8. [PMID: 19713093 DOI: 10.1016/j.coi.2009.07.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Accepted: 07/28/2009] [Indexed: 11/30/2022]
Abstract
Transplantation has emerged as the therapy of choice for many patients with end organ failure. One of the major goals is to tailor immunosuppressive therapy to the individual needs of every patient to balance the risk for rejection and over-immunosuppression. This will require diagnostic tools that can detect harmful processes in the allograft early, and that can be measured repeatedly. This review will consider recent advances in our understanding of the molecular nature of these processes and how this information is being utilized to design novel diagnostic assays to non-invasively monitor allografts. Highlighted is the need for large-scale prospective multi-centre studies to validate assays that show early promise in single centre studies.
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Affiliation(s)
- Peter Nickerson
- Manitoba Centre for Proteomics and Systems Biology, University of Manitoba, 799 John Buhler Research Centre, 715 McDermot Avenue, Winnipeg, Manitoba, Canada R3E 3P4.
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Jia X, Gan C, Xiao K, He W, Zhang T, Huang C, Wu X, Luo G, Wang X, Hu J, Tan J, Zhang X, Larsen PM, Wu J. Detection of urinary biomarkers for early diagnosis of acute renal allograft rejection by proteomic analysis. Proteomics Clin Appl 2009; 3:694-704. [DOI: 10.1002/prca.200800209] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Schaub S, Nickerson P, Rush D, Mayr M, Hess C, Golian M, Stefura W, Hayglass K. Urinary CXCL9 and CXCL10 levels correlate with the extent of subclinical tubulitis. Am J Transplant 2009; 9:1347-53. [PMID: 19459809 DOI: 10.1111/j.1600-6143.2009.02645.x] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Subclinical tubulitis has been associated with the later development of interstitial fibrosis and tubular atrophy (IF/TA), leading to diminished allograft survival. The aim of this study was to investigate how concentrations of urinary CXC-receptor 3 (CXCR3) chemokines (i.e. CXCL4/9/10/11) and CCL2 relate to the extent of subclinical tubulitis. Using ELISA, urinary CXCR3 chemokines, CCL2 and tubular injury markers (i.e. urinary NGAL and alpha1-microglobulin [alpha1 m]) were measured in patients with stable estimated GFR >or=40 mL/min exhibiting normal tubular histology (n = 24), subclinical borderline tubulitis (n = 18) or subclinical tubulitis Ia/Ib (n = 22), as well as in patients with clinical tubulitis Ia/Ib (n = 17) or IF/TA (n = 10). CXCL9 and CXCL10 were significantly higher in subclinical tubulitis Ia/Ib than in subclinical borderline tubulitis (p <or= 0.03) and normal tubular histology (p <or= 0.0002). By contrast, NGAL, alpha1-m, CXCL4, CXCL11 and CCL2 were not or only marginally distinctive across these patient groups. All urinary chemokines and tubular injury markers were higher in clinical tubulitis Ia/Ib than in normal tubular histology (p <or= 0.002), but only tubular injury markers were elevated in IF/TA. These results demonstrate a correlation of urinary CXCL9 and CXCL10 levels with the extent of subclinical tubulitis suggesting potential as noninvasive screening biomarkers.
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Affiliation(s)
- S Schaub
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland.
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Using Biomarkers of Tolerance and Rejection to Identify High- and Low-Risk Patients Following Kidney Transplantation. Transplantation 2009; 87:S95-9. [DOI: 10.1097/tp.0b013e3181a2e295] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Chronic allograft nephropathy, now defined as interstital fibrosis and tubular atrophy not otherwise specified, is a near universal finding in transplant kidney biopsies by the end of the first decade posttransplantation. After excluding death with functioning graft, caused by cardiovascular disease or malignancy, chronic allograft nephropathy is the leading cause of graft failure. Original assumptions were that this was not a modifiable process but inexorable, likely due to past kidney injuries. However, newer understandings suggest that acute or subacute processes are involved, and with proper diagnosis, appropriate interventions can be instituted. Our method involved a review of the primary and secondary prevention trials in calcineurin inhibitor withdrawal. Some of the more important causes of progressive graft deterioration include subclinical cellular or humoral rejection, and chronic calcineurin inhibitor toxicity. Early graft biopsy, assessment of histology, and changes in immunosuppression may be some of the most important measures available to protect graft function. The avoidance of clinical inertia in pursuing subtle changes in graft function is critical. Modification in maintenance immunosuppression may benefit many patients with early evidence of graft deterioration.
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40
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Reuter S, Schnöckel U, Schröter R, Schober O, Pavenstädt H, Schäfers M, Gabriëls G, Schlatter E. Non-invasive imaging of acute renal allograft rejection in rats using small animal F-FDG-PET. PLoS One 2009; 4:e5296. [PMID: 19390685 PMCID: PMC2669171 DOI: 10.1371/journal.pone.0005296] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2008] [Accepted: 03/30/2009] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND At present, renal grafts are the most common solid organ transplants world-wide. Given the importance of renal transplantation and the limitation of available donor kidneys, detailed analysis of factors that affect transplant survival are important. Despite the introduction of new and effective immunosuppressive drugs, acute cellular graft rejection (AR) is still a major risk for graft survival. Nowadays, AR can only be definitively by renal biopsy. However, biopsies carry a risk of renal transplant injury and loss. Most important, they can not be performed in patients taking anticoagulant drugs. METHODOLOGY/PRINCIPAL FINDINGS We present a non-invasive, entirely image-based method to assess AR in an allogeneic rat renal transplantation model using small animal positron emission tomography (PET) and (18)F-fluorodeoxyglucose (FDG). 3 h after i.v. injection of 30 MBq FDG into adult uni-nephrectomized, allogeneically transplanted rats, tissue radioactivity of renal parenchyma was assessed in vivo by a small animal PET-scanner (post operative day (POD) 1,2,4, and 7) and post mortem dissection. The mean radioactivity (cps/mm(3) tissue) as well as the percent injected dose (%ID) was compared between graft and native reference kidney. Results were confirmed by histological and autoradiographic analysis. Healthy rats, rats with acute CSA nephrotoxicity, with acute tubular necrosis, and syngeneically transplanted rats served as controls. FDG-uptake was significantly elevated only in allogeneic grafts from POD 1 on when compared to the native kidney (%ID graft POD 1: 0.54+/-0.06; POD 2: 0.58+/-0.12; POD 4: 0.81+/-0.06; POD 7: 0.77+/-0.1; CTR: 0.22+/-0.01, n = 3-28). Renal FDG-uptake in vivo correlated with the results obtained by micro-autoradiography and the degree of inflammatory infiltrates observed in histology. CONCLUSIONS/SIGNIFICANCE We propose that graft FDG-PET imaging is a new option to non-invasively, specifically, early detect, and follow-up acute renal rejection. This method is potentially useful to improve post-transplant rejection monitoring.
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Affiliation(s)
- Stefan Reuter
- Medizinische Klinik und Poliklinik D, Experimentelle Nephrologie, Universitätsklinikum Münster, Münster, Germany.
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Abstract
CONTEXT The first renal biopsy was carried out more than a century ago, but its widespread introduction into clinical use, beginning in the 1950s, helped develop nephrology into the powerful subspecialty of internal medicine that it is today. In the past 25 years, the use of the spring-loaded biopsy gun, in combination with newer visualization techniques, including ultrasound and computed axial tomography scanning, has led to greater tissue yield and to a much lower risk of complication. During this same time, our understanding of renal pathology has increased many fold. Correct fixation and processing of renal biopsy tissue is critical, and the laboratory must be skilled with renal biopsy light microscopy, immunohistochemistry, and transmission electron microscopy preparation. OBJECTIVES To provide an overview of the renal biopsy, including the techniques and its complications, and to summarize proper laboratory methods for processing renal biopsy tissue. DATA SOURCES This article is based on a review of the literature and on the experience of the author. CONCLUSIONS The experienced nephropathologist, knowledgeable in both renal medicine and pathology and thus able to correlate subtle tissue-derived information with appropriate clinical data, remains the most important key to the development of an accurate clinicopathologic diagnosis.
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Affiliation(s)
- Patrick D Walker
- Nephropathology Associates, 10810 Executive Center Drive, Little Rock, AR 72211, USA.
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Ashton-Chess J, Giral M, Soulillou JP, Brouard S. Can immune monitoring help to minimize immunosuppression in kidney transplantation? Transpl Int 2008; 22:110-9. [PMID: 18764832 DOI: 10.1111/j.1432-2277.2008.00748.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The serious side-effects and complications related to the life-long use of immunosuppressors in transplantation have fuelled research into their possible minimization or even complete elimination. The field of transplantation is therefore tentatively moving from a phase of empiric immunosuppression towards individualized therapy. This process is highly dependent on the development of immune monitoring tests to detect an individual 'level of risk'. Immune monitoring is a way of measuring functional and molecular correlates of immune reactivity to provide clinically useful information for therapeutic decision-making. The technological breakthroughs over the last decade provide firm grounds for the achievement of this goal. Large, multicentric and prospective studies in the near future are now crucial if these tests are to achieve the necessary approval from the regulatory authorities and promptly enter the clinic for routine use.
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Affiliation(s)
- Joanna Ashton-Chess
- INSERM, Institute de Transplantation Et de Recherche en Transplantation, Nantes, France.
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Ushigome H, Sakai K, Suzuki T, Nobori S, Yoshizawa A, Kaihara S, Okamoto M, Urasaki K, Yoshimura N. Utility of protocol biopsy for the early diagnosis of transplanted kidney dysfunction. Clin Transplant 2008. [DOI: 10.1111/j.1399-0012.2008.00841.x] [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]
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Schaub S, Mayr M, Hönger G, Bestland J, Steiger J, Regeniter A, Mihatsch MJ, Wilkins JA, Rush D, Nickerson P. Detection of subclinical tubular injury after renal transplantation: comparison of urine protein analysis with allograft histopathology. Transplantation 2007; 84:104-12. [PMID: 17627245 DOI: 10.1097/01.tp.0000268808.39401.e8] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND Tubulointerstitial injury due to rejection leads to tubular atrophy (TA)/interstitial fibrosis (IF) followed by deterioration of allograft function. This study investigated whether urinary tubular injury biomarkers can detect subclinical tubulitis found in protocol biopsies allowing for a noninvasive screening procedure. METHODS Four rigidly defined groups (stable transplants with normal tubular histology [n=24], stable transplants with subclinical tubulitis [n=38], patients with clinical tubulitis Ia/Ib [n=18], and patients with other clinical tubular pathologies [n=20]) were compared for differences in urinary intact/cleaved beta2-microglobulin (i/cbeta2m), retinol-binding protein (RBP), neutrophil-gelatinase-associated lipocalin (NGAL), and alpha1-microglobulin (alpha1m). RESULTS Tubular proteinuria was present in 38% (RBP) to 79% (alpha1m) of patients in the stable transplant with normal tubular histology group. The stable transplant with subclinical tubulitis group had slightly higher levels of i/cbeta2m (P=0.11), RBP (P=0.17), alpha1m (P=0.09), and NGAL (P=0.06) than the stable transplant with normal tubular histology group with a substantial overlap. The clinical tubulitis Ia/Ib and the other clinical tubular pathology groups had significantly higher levels of RBP, NGAL, and alpha1m than stable transplants with normal tubular histology or stable transplants with subclinical tubulitis (P<0.002). CONCLUSIONS None of the investigated biomarkers allow for clear differentiation between stable transplants with normal tubular histology and stable transplants with subclinical tubulitis. Therefore, the protocol allograft biopsy currently remains the preferred tool to screen for subclinical tubulitis. Further longitudinal studies should determine whether tubular proteinuria in stable transplants with normal tubular histology indicates a clear risk for early development of TA/IF.
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Affiliation(s)
- Stefan Schaub
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland.
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Hymes LC, Greenbaum L, Amaral SG, Warshaw BL. Surveillance renal transplant biopsies and subclinical rejection at three months post-transplant in pediatric recipients. Pediatr Transplant 2007; 11:536-9. [PMID: 17631023 DOI: 10.1111/j.1399-3046.2007.00705.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
UNLABELLED Subclinical acute rejection (SCR) has been increasingly recognized in adult renal transplant recipients with the advent of surveillance biopsies. However, in children, surveillance biopsies are not routinely performed at most centers. Therefore, the incidence, predisposing factors, treatment, and clinical outcomes of SCR remain unclear in children. From August 2004 to December 2005, we performed 36 protocol biopsies at three months post-transplantation. All patients had received induction therapy with basiliximab and were maintained on prednisone, MMF, and tacrolimus. Sixteen cases of SCR were detected by biopsy (44%). Age, gender, race, donor source, or serum creatinine did not discriminate between children with SCR and those with normal biopsies. All cases of SCR were treated with high doses of methylprednisolone. At one yr post-transplant, renal function was similar in children with SCR to those with normal surveillance biopsies (p = 0.62). Because of the high incidence of SCR, the maintenance dose of MMF was increased by 50% in 20 children transplanted after December 2005. This resulted in a significant decline in the incidence of SCR from 44 to 15% (p < 0.05). However, the incidence of polyomavirus (BK) viremia also increased significantly in these children (p < 0.005). CONCLUSION A high incidence of SCR was found on surveillance biopsies at three months post-transplant and could not be predicted by age, gender, race, donor source, or serum creatinine. The occurrence of SCR declined significantly by increasing the dose of MMF, but resulted in an increase in BK viremia. We conclude that surveillance biopsies provide valuable information in the management of pediatric renal transplant recipients. Increasing immunosuppression to avoid SCR should be weighed against the risk for infection.
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Affiliation(s)
- Leonard C Hymes
- Department of Pediatrics, Division of Nephrology, Emory University, 2015 Uppergate Drive, Atlanta, GA 30322, USA.
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Birk PE, Blydt-Hansen TD, Dart AB, Kaita LM, Proulx C, Taylor G. Low incidence of adverse events in outpatient pediatric renal allograft biopsies. Pediatr Transplant 2007; 11:196-200. [PMID: 17300500 DOI: 10.1111/j.1399-3046.2006.00659.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In 1999, our center implemented a policy of outpatient protocol biopsies as standard practice for the clinical management of pediatric renal allograft recipients. In order to determine the safety of this procedure, we conducted a retrospective chart audit of all outpatient renal allograft biopsies performed at our center. Biopsies were performed under conscious (midazolam) or procedural (propofol/fentanyl) sedation. Localization of the lower pole of the renal allograft was achieved with renal ultrasound. Using a Biopty gun with a 16-gauge needle, two cores were obtained. Patients were discharged four h post-biopsy. Patient demographics, hospital length of stay (LOS), specimen adequacy (per Banff criteria) and major and minor adverse events were recorded in a central database. Data were expressed as mean +/- SD. From June 1999 to July 2004, we performed 162 biopsies in 43 pediatric renal allograft recipients. Most patients underwent extraperitoneal transplantation (42/43, 97.7%) and were greater than five yr of age at biopsy (129/131 biopsies, 98.5%). The majority of these procedures (131/162, 80.9%) were conducted in the outpatient department, with 113 of 131 (86.3%) being obtained for protocol (n = 89) and one-month follow-up acute rejection therapy (n = 24) indications. Patients underwent 3.7 +/- 2.7 biopsies (range = 1-11). Specimen adequacy was achieved in 119 of 124 (96.0%) of documented cases. The overall incidence of adverse events was 12 of 131 (9.2%) biopsies, all of which were minor in severity. Macroscopic hematuria was the most common minor adverse event, occurring after 11 of 131 (8.4%) biopsies. While macroscopic hematuria prolonged LOS (adverse events vs. no adverse events: 23.0 +/- 26.0 vs. 8.6 +/- 4.1 h, p = 0), none of these episodes required major surgical or radiographic interventions. We conclude that in patients greater than five yr of age with extraperitoneal renal allografts, outpatient protocol biopsies using a 16-gauge needle are sufficiently safe to justify their inclusion in the routine clinical management of pediatric renal allograft recipients and in pediatric clinical trials.
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Affiliation(s)
- Patricia E Birk
- Department of Pediatrics, University of Manitoba, Winnipeg, Manitoba, Canada.
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