Prognostic Biomarkers in Kidney Transplantation: A Systematic Review and Critical Appraisal.

SIGNIFICANCE STATEMENT: Why are there so few biomarkers accepted by health authorities and implemented in clinical practice, despite the high and growing number of biomaker studies in medical research ? In this meta-epidemiological study, including 804 studies that were critically appraised by expert reviewers, the authors have identified all prognostic kidney transplant biomarkers and showed overall suboptimal study designs, methods, results, interpretation, reproducible research standards, and transparency. The authors also demonstrated for the first time that the limited number of studies challenged the added value of their candidate biomarkers against standard-of-care routine patient monitoring parameters. Most biomarker studies tended to be single-center, retrospective studies with a small number of patients and clinical events. Less than 5% of the studies performed an external validation. The authors also showed the poor transparency reporting and identified a data beautification phenomenon. These findings suggest that there is much wasted research effort in transplant biomarker medical research and highlight the need to produce more rigorous studies so that more biomarkers may be validated and successfully implemented in clinical practice. BACKGROUND: Despite the increasing number of biomarker studies published in the transplant literature over the past 20 years, demonstrations of their clinical benefit and their implementation in routine clinical practice are lacking. We hypothesized that suboptimal design, data, methodology, and reporting might contribute to this phenomenon. METHODS: We formed a consortium of experts in systematic reviews, nephrologists, methodologists, and epidemiologists. A systematic literature search was performed in PubMed, Embase, Scopus, Web of Science, and Cochrane Library between January 1, 2005, and November 12, 2022 (PROSPERO ID: CRD42020154747). All English language, original studies investigating the association between a biomarker and kidney allograft outcome were included. The final set of publications was assessed by expert reviewers. After data collection, two independent reviewers randomly evaluated the inconsistencies for 30% of the references for each reviewer. If more than 5% of inconsistencies were observed for one given reviewer, a re-evaluation was conducted for all the references of the reviewer. The biomarkers were categorized according to their type and the biological milieu from which they were measured. The study characteristics related to the design, methods, results, and their interpretation were assessed, as well as reproducible research practices and transparency indicators. RESULTS: A total of 7372 publications were screened and 804 studies met the inclusion criteria. A total of 1143 biomarkers were assessed among the included studies from blood ( n =821, 71.8%), intragraft ( n =169, 14.8%), or urine ( n =81, 7.1%) compartments. The number of studies significantly increased, with a median, yearly number of 31.5 studies (interquartile range [IQR], 23.8-35.5) between 2005 and 2012 and 57.5 (IQR, 53.3-59.8) between 2013 and 2022 ( P < 0.001). A total of 655 studies (81.5%) were retrospective, while 595 (74.0%) used data from a single center. The median number of patients included was 232 (IQR, 96-629) with a median follow-up post-transplant of 4.8 years (IQR, 3.0-6.2). Only 4.7% of studies were externally validated. A total of 346 studies (43.0%) did not adjust their biomarker for key prognostic factors, while only 3.1% of studies adjusted the biomarker for standard-of-care patient monitoring factors. Data sharing, code sharing, and registration occurred in 8.8%, 1.1%, and 4.6% of studies, respectively. A total of 158 studies (20.0%) emphasized the clinical relevance of the biomarker, despite the reported nonsignificant association of the biomarker with the outcome measure. A total of 288 studies assessed rejection as an outcome. We showed that these rejection studies shared the same characteristics as other studies. CONCLUSIONS: Biomarker studies in kidney transplantation lack validation, rigorous design and methodology, accurate interpretation, and transparency. Higher standards are needed in biomarker research to prove the clinical utility and support clinical use.

Unveiling a new era with liquid chromatography coupled with mass spectrometry to enhance parathyroid hormone measurement in patients with chronic kidney disease.

Precise determination of circulating parathyroid hormone (PTH) concentration is crucial to diagnose and manage various disease conditions, including the chronic kidney disease-mineral and bone disorder. However, the lack of standardization in PTH assays is challenging for clinicians, potentially leading to medical errors because the different assays do not provide equivalent results and use different reference ranges. Here, we aimed to evaluate the impact of recalibrating PTH immunoassays by means of a recently developed LC-MS/MS method as the reference. Utilizing a large panel of pooled plasma samples with PTH concentrations determined by the LC-MS/MS method calibrated with the World Health Organization (WHO) 95/646 International Standard, five PTH immunoassays were recalibrated. The robustness of this standardization was evaluated over time using different sets of samples. The recalibration successfully reduced inter-assay variability with harmonization of PTH measurements across different assays. By recalibrating the assays based on the WHO 95/646 International Standard, we demonstrated the feasibility for standardizing PTH measurement results and adopting common reference ranges for PTH assays, facilitating a more consistent interpretation of PTH values. The recalibration process aligns PTH results obtained from various immunoassays with the LC-MS/MS method, providing more consistent and reliable measurements. Thus, establishing true standardization across all PTH assays is crucial to ensure consistent interpretation and clinical decision-making.

[Delayed graft function : an ongoing clinical challenge]. / Reprise retardée de fonction du greffon après transplantation rénale : un challenge clinique toujours d'actualité.

Delayed Graft Function (DGF) is defined as the need for dialysis during the first week after transplantation. DGF is frequent and mostly derived from the ischemia/reperfusion cascade to which the graft is subjected throughout the transplantation process. A graft biopsy is recommended after 7 days of DGF to exclude an episode of acute rejection. Note that DGF per se is associated with an increased risk of acute graft rejection, as well as with a shorter long-term graft survival. Several strategies are being studied to mitigate the ischaemic damage, thereby improving graft quality. Among these, cellular therapy using mesenchymal stromal cells (MSC) is promising, in particular via the administration of MSC in the machine perfusion during the preservation of the graft. We will discuss here the different definitions of DGF and the main predictive factors of DGF, as well as the impact on the graft outcomes. The current strategies to prevent DGF will be briefly reviewed.

La reprise retardée de fonction du greffon rénal (DGF en anglais pour Delayed Graft Function), définie notamment par la nécessité de dialyse durant la 1ère semaine après transplantation, reste un événement fréquent. La DGF résulte principalement des phénomènes d'ischémie/reperfusion auxquels le greffon est soumis tout au long du processus de transplantation. Néanmoins, une biopsie du greffon est préconisée après 7 jours de DGF afin d'exclure une cause non ischémique telle qu'un rejet aigu. La DGF est per se associée à un risque accru de rejet du greffon, ainsi qu'à une moins bonne survie du greffon rénal au long cours. Plusieurs stratégies sont étudiées afin d'atténuer les dommages ischémiques et améliorer la qualité du greffon. Parmi celles-ci, la thérapie cellulaire par cellules stromales mésenchymateuses est prometteuse, notamment via l'administration de celles-ci dans la machine de perfusion lors de la préservation du greffon. Nous aborderons les différentes définitions de la DGF ainsi que ses principaux facteurs prédictifs, l'impact sur le devenir du greffon et, brièvement, les stratégies actuelles dans le cadre de la prévention de la DGF.

Age-adapted percentiles of measured glomerular filtration in healthy individuals: extrapolation to living kidney donors over 65 years.

OBJECTIVES: Most data on glomerular filtration rate (GFR) originate from subjects <65 years old, complicating decision-making in elderly living kidney donors. In this retrospective multi-center study, we calculated percentiles of measured GFR (mGFR) in donors <65 years old and extrapolated these to donors ≥65 years old. METHODS: mGFR percentiles were calculated from a development cohort of French/Belgian living kidney donors <65 years (n=1,983), using quantiles modeled as cubic splines (two linear parts joining at 40 years). Percentiles were extrapolated and validated in an internal cohort of donors ≥65 years (n=147, France) and external cohort of donors and healthy subjects ≥65 years (n=329, Germany, Sweden, Norway, France, The Netherlands) by calculating percentages within the extrapolated 5th-95th percentile (P5-P95). RESULTS: Individuals in the development cohort had a higher mGFR (99.9 ± 16.4 vs. 86.4 ± 14 and 82.7 ± 15.5 mL/min/1.73 m2) compared to the individuals in the validation cohorts. In the internal validation cohort, none (0%) had mGFR below the extrapolated P5, 12 (8.2%) above P95 and 135 (91.8%) between P5-P95. In the external validation cohort, five subjects had mGFR below the extrapolated P5 (1.5%), 25 above P95 (7.6%) and 299 (90.9%) between P5-P95. CONCLUSIONS: We demonstrate that extrapolation of mGFR from younger donors is possible and might aid with decision-making in elderly donors.

Assessment of the Utility of Kidney Histology as a Basis for Discarding Organs in the United States: A Comparison of International Transplant Practices and Outcomes.

BACKGROUND: Many kidneys donated for transplant in the United States are discarded because of abnormal histology. Whether histology adds incremental value beyond usual donor attributes in assessing allograft quality is unknown. METHODS: This population-based study included patients who received a deceased donor kidney that had been biopsied before implantation according to a prespecified protocol in France and Belgium, where preimplantation biopsy findings are generally not used for decision making in the allocation process. We also studied kidneys that had been acquired from deceased United States donors for transplantation that were biopsied during allocation and discarded because of low organ quality. Using donor and recipient characteristics, we fit multivariable Cox models for death-censored graft failure and examined whether predictive accuracy (C index) improved after adding donor histology. We matched the discarded United States kidneys to similar kidneys transplanted in Europe and calculated predicted allograft survival. RESULTS: In the development cohort of 1629 kidney recipients at two French centers, adding donor histology to the model did not significantly improve prediction of long-term allograft failure. Analyses using an external validation cohort from two Belgian centers confirmed the lack of improved accuracy from adding histology. About 45% of 1103 United States kidneys discarded because of histologic findings could be accurately matched to very similar kidneys that had been transplanted in France; these discarded kidneys would be expected to have allograft survival of 93.1% at 1 year, 80.7% at 5 years, and 68.9% at 10 years. CONCLUSIONS: In this multicenter study, donor kidney histology assessment during allocation did not provide substantial incremental value in ascertaining organ quality. Many kidneys discarded on the basis of biopsy findings would likely benefit United States patients who are wait listed.

Diagnostic yield of 18 F-FDG PET/CT imaging and urinary CXCL9/creatinine levels in kidney allograft subclinical rejection.

Subclinical kidney allograft acute rejection (SCR) corresponds to "the unexpected histological evidence of acute rejection in a stable patient." SCR detection relies on surveillance biopsy. Noninvasive approaches may help avoid biopsy-associated complications. From November 2015 to January 2018, we prospectively performed positron emission tomography/computed tomography (PET/CT) after injection of F18 -fluorodeoxyglucose (18 F-FDG) in adult kidney transplant recipients with surveillance biopsy at ~3 months posttransplantation. The Banff-2017 classification was used. The ratio of the mean standard uptake value (mSUVR) between kidney cortex and psoas muscle was measured. Urinary levels of CXCL-9 were concomitantly quantified. Our 92-patient cohort was categorized upon histology: normal (n = 70), borderline (n = 16), and SCR (n = 6). No clinical or biological difference was observed between groups. The mSUVR reached 1.87 ± 0.55, 1.94 ± 0.35, and 2.41 ± 0.54 in normal, borderline, and SCR groups, respectively. A significant difference in mSUVR was found among groups. Furthermore, mSUVR was significantly higher in the SCR vs normal group. The area under the receiver operating characteristic curve (AUC) was 0.79, with 83% sensitivity using an mSUVR threshold of 2.4. The AUC of urinary CXCL-9/creatinine ratios comparatively reached 0.79. The mSUVR positively correlated with ti and acute composite Banff scores. 18 F-FDG-PET/CT helps noninvasively exclude SCR, with a negative predictive value of 98%. External validations are required.

[How to estimate glomerular filtration rate in the context of drug dosage adaptation†?] / Comment estimer la filtration glomérulaire dans le contexte de l'adaptation posologique de médicaments†?

In chronic kidney disease (CKD) patients, the dosage of many medications should be adapted according to the glomerular filtration rate (GFR). GFR estimation is obtained by using creatinine-based equations. Many different equations have been proposed in the literature, and they don't systematically lead to the same result in terms of drug dosage. There is an ongoing debate to determine which equations should be recommended, with the Cockcroft equation on one side and the MDRD («â€…Modified Diet in Renal Diseases ¼) or CKD-EPI («â€…Chronic Kidney Disease Epidemiology ¼) on the other side. The last two equations are especially used by nephrologists whereas the Cockcroft is still considered by geriatrists and pharmacologists. In the current article, we discuss the pro/cons from both sides, and propose recommendation for the clinical practice.

En cas de maladie rénale chronique, il convient d'ajuster la dose des médicaments au débit de filtration glomérulaire (DFG). L'estimation du DFG est obtenue à partir de formules basées sur la mesure de la créatinine sérique. Plusieurs formules existent dans la littérature et elles n'aboutissent pas toujours à la même conclusion en termes d'adaptation posologique. Le débat dans la littérature sur le choix de la formule se pose entre celle de Cockcroft et Gault et celles appelées Modified Diet in Renal Diseases (MDRD) ou Chronic Kidney Disease Epidemiology (CKD-EPI). Ces dernières sont surtout utilisées en néphrologie, alors que celle de Cockcroft reste très usitée en gériatrie et en pharmacologie. Nous discuterons des arguments des uns et des autres, en finissant par quelques recommandations pratiques.

Complement-activating donor-specific anti-HLA antibodies and solid organ transplant survival: A systematic review and meta-analysis.

BACKGROUND: Anti-human leukocyte antigen donor-specific antibodies (anti-HLA DSAs) are recognized as a major barrier to patients' access to organ transplantation and the major cause of graft failure. The capacity of circulating anti-HLA DSAs to activate complement has been suggested as a potential biomarker for optimizing graft allocation and improving the rate of successful transplantations. METHODS AND FINDINGS: To address the clinical relevance of complement-activating anti-HLA DSAs across all solid organ transplant patients, we performed a meta-analysis of their association with transplant outcome through a systematic review, from inception to January 31, 2018. The primary outcome was allograft loss, and the secondary outcome was allograft rejection. A comprehensive search strategy was conducted through several databases (Medline, Embase, Cochrane, and Scopus). A total of 5,861 eligible citations were identified. A total of 37 studies were included in the meta-analysis. Studies reported on 7,936 patients, including kidney (n = 5,991), liver (n = 1,459), heart (n = 370), and lung recipients (n = 116). Solid organ transplant recipients with circulating complement-activating anti-HLA DSAs experienced an increased risk of allograft loss (pooled HR 3.09; 95% CI 2.55-3.74, P = 0.001; I2 = 29.3%), and allograft rejection (pooled HR 3.75; 95% CI: 2.05-6.87, P = 0.001; I2 = 69.8%) compared to patients without complement-activating anti-HLA DSAs. The association between circulating complement-activating anti-HLA DSAs and allograft failure was consistent across all subgroups and sensitivity analyses. Limitations of the study are the observational and retrospective design of almost all included studies, the higher proportion of kidney recipients compared to other solid organ transplant recipients, and the inclusion of fewer studies investigating allograft rejection. CONCLUSIONS: In this study, we found that circulating complement-activating anti-HLA DSAs had a significant deleterious impact on solid organ transplant survival and risk of rejection. The detection of complement-activating anti-HLA DSAs may add value at an individual patient level for noninvasive biomarker-guided risk stratification. TRIAL REGISTRATION: National Clinical Trial protocol ID: NCT03438058.

Correction: Complement-activating donor-specific anti-HLA antibodies and solid organ transplant survival: A systematic review and meta-analysis.

[This corrects the article DOI: 10.1371/journal.pmed.1002572.].

Sclerostin and chronic kidney disease: the assay impacts what we (thought to) know.

Background: Sclerostin, a 22-kDa protein secreted by osteocytes, acts as a potent inhibitor of osteoblast activity. In chronic kidney disease (CKD), sclerostin is a putative driver of the bone-vascular axis. However, large discrepancies between sclerostin assays have been described. Methods: We compared four different assays [Biomedica (BM), TecoMedical (TE), R&D (RD) and MesoScaleDiscovery (MSD)] in an analytical study and addressed the question whether bioassay choice affects the correlation between circulating sclerostin and clinical and biochemical determinants. Circulating sclerostin levels were determined in 39 prevalent dialysis patients and 82 non-dialysis patients referred for glomerular filtration rate measurement. Results: In the 82 non-dialysis patients, we observed large differences in median (interquartile range) sclerostin concentrations (in pg/mL): BM, 984 [interquartile range (IQR) 648]; TE, 629 (IQR 237); RD, 154 (IQR 84) and MSD, 36 (IQR 19). The concordance correlation coefficient between assays was poor (0.1-0.44). The same discrepancies were observed in dialysis patients. A significant negative rank correlation was found between glomerular filtration rate and sclerostin measured by BM and TE but not by MSD and RD. Associations between sclerostin and age, gender, weight or parathormone were also different according to the assay considered. Conclusions: Clinical inference relating sclerostin levels found in the general, CKD and dialysis populations is largely influenced by the assay used to measure this biomarker.

Creatinine-based equations for the adjustment of drug dosage in an obese population.

AIM: For drug dosing adaptation, the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines recommend using estimated glomerular filtration rate (eGFR) by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, after 'de-indexation' by body surface area (BSA). In pharmacology, the Cockcroft-Gault (CG) equation is still recommended to adapt drug dosage. In the context of obesity, adjusted ideal body weight (AIBW) is sometimes preferred to actual body weight (ABW) for the CG equation. The aim of the present study was to compare the performance of the different GFR-estimating equations, non-indexed or de-indexed by BSA for the purpose of drug-dosage adaptation in obese patients. METHODS: We analysed data from patients with a body mass index (BMI) higher than 30 kg m(-2) who underwent a GFR measurement. eGFR was calculated using the CKD-EPI and Modification of Diet in Renal Disease (MDRD) equations, de-indexed by BSA, and the CG equation, using either ABW, AIBW or lean body weight (LBW) for the weight variable and compared with measured GFR, expressed in ml min(-1). RESULTS: In our population of obese patients, use of the AIBW instead of the ABW in the CG equation, markedly improved the overall accuracy of this equation [57% for CGABW and 79% for CGAIBW (P < 0.05)]. For high BMI (over 40 kg m(-2)), the accuracy of the CG equations is no different when using LBW than when using AIBW. The MDRD and CKD-EPI equations de-indexed by the BSA also performed well, with an overall higher accuracy for the MDRD de-indexed equation [(80% and 76%, respectively (P < 0.05)]. CONCLUSIONS: The de-indexed MDRD equation appeared to be the most suitable for estimating the non-indexed GFR for the purpose of drug dosage adaptation in obese patients.

Sclerostin levels in CKD patients: an important, but not definitive, step on the way to clinical use.

Sclerostin, an inhibitor of the Wnt signaling pathway, inhibits bone formation. In a study of vascular biopsies of patients undergoing kidney transplantation, Qureshi et al. demonstrate that circulating sclerostin levels are associated with vascular calcification (VC). This adds to an emerging body of literature implicating sclerostin as a key link between chronic kidney disease-mineral and bone disorder and cardiovascular disease. Some confounders of this association remain, and the mechanisms by which sclerostin promotes VC have yet to be elucidated.

Insight into the potential of bone turnover biomarkers: integration in the management of osteoporosis and chronic kidney disease-associated osteoporosis.

PURPOSE OF REVIEW: Disturbances in mineral and bone metabolism occurring in osteoporosis and chronic kidney disease-associated osteoporosis place patients at high risk of fracture making these conditions a major public health concern. Due to the limited use of bone histomorphometry in clinical practice, the gold standard for assessing bone turnover, extensive efforts have been made to identify bone turnover markers (BTMs) as noninvasive surrogates. Since the identification of certain commonly used markers several decades ago, considerable experience has been acquired regarding their clinical utility in such bone disorders. RECENT FINDINGS: Mounting evidence suggested that BTMs represent a simple, low-risk, rapid and convenient way to obtain data on the skeletal health and that they may be useful in guiding therapeutic choices and monitoring the response to treatment. SUMMARY: BTMs could provide clinicians with useful information, independent from, and often complementary to bone mineral density (BMD) measurements. They have proven valuable for monitoring the effectiveness of osteoporosis therapy, as well as promising for discriminating low and high turnover states. Improved performance is observed when BTMs are combined, which may be useful for selecting treatments for chronic kidney disease-bone mineral disorders (CKD-MBD).

Management of immunosuppressive therapy after functional renal graft failure: results of a practice survey of French-speaking nephrologists / Gestion du traitement immunosuppresseur après arrêt fonctionnel du greffon rénal : résultats d'une enquête de pratique parmi les néphrologues francophones.

The management of patients with kidney transplant failure (KTF) remains a complex process involving multiple stakeholders. A working group of the Transplantation Commission of the French-speaking Society of Nephrology, Dialysis and Transplantation (SFNDT) conducted a survey on the management of immunosuppressants (IS) after KTF among nephrologists at transplant centres and general nephrologists in France, Switzerland and Belgium between March and June 2023. We analysed 232 replies from 58 nephrologists at transplant centres and 174 general nephrologists, aged 43.6 (+10.6) years. In the first three months following KTF, nephrologists reported discontinuing antimetabolite, calcineurin inhibitor (CNI) and corticosteroid treatment in 83%, 39.9% and 25.8% of cases respectively. Conversely, some nephrologists reported that they were continuing to use CNI (14%) and corticosteroids (19.1%) on a long-term basis. The patient's comorbidities associated with the discontinuation of IS treatment are cancer and opportunistic infections as KT's complications and presence of diabetes mellitus at KTF, whereas humoral rejection encourages the IS to be maintained. Transplantectomy is proposed by nephrologists most often for graft intolerance syndrome (86.5%), more rarely to discontinue IS (17.6%) or in the absence of plans of new transplantation (9.3%). In multivariate analyses, the presence of a protocol in the centre facilitated the management of IS by the general nephrologists. The management of IS after AFG by French-speaking nephrologists is heterogeneous. Specific prospective studies are needed to establish new best practice recommendations, based on more robust evidence, which could encourage better adherence by nephrologists.

La prise en charge des patients avec un arrêt fonctionnel du greffon rénal (AFG) reste un processus complexe avec de multiples intervenants. Un groupe de travail de la Société francophone de néphrologie, dialyse et transplantation (SFNDT) a conduit une enquête sur la gestion des traitements immunosuppresseurs (IS) après AFG parmi les néphrologues de centres de transplantation et néphrologues généraux en France, Suisse et Belgique francophone entre mars et juin 2023. Nous avons pu analyser 232 réponses de néphrologues (centres de transplantation N = 58 et généraux N = 174) âgés de 43,6 (± 10,6) ans. Dans les 3 premiers mois suivant l'AFG, les néphrologues déclarent interrompre le traitement par antimétabolites (83 %), inhibiteurs de la calcineurine (ICN) (39,9 %) et corticoïdes (25,8 %). À l'inverse, certains déclarent maintenir les ICN (14 %) et les corticoïdes (19,1 %) au long cours en cas de projet de nouvelle transplantation rénale (TR). La survenue de cancer pendant la TR, d'infections opportunistes dans la dernière année de TR ou à l'initiation de la dialyse, et la présence d'un diabète lors de l'AFG sont associées avec l'arrêt du traitement IS alors que la perte du greffon par rejet humoral incite à le maintenir. En analyse multivariée, la présence d'un protocole dans le centre facilite la gestion des IS par les néphrologues généraux. Enfin, la transplantectomie est proposée par les néphrologues le plus souvent pour un syndrome d'intolérance du greffon (86,5 %), plus rarement pour interrompre les IS (17,6 %) ou en l'absence de projet de nouvelle TR (9,3 %). La gestion des IS après l'AFG par les néphrologues francophones est hétérogène. Des études prospectives spécifiques sont nécessaires afin de formuler de nouvelles recommandations de bonnes pratiques, reposant sur des données probantes plus robustes, qui pourraient encourager une meilleure adhésion par les néphrologues.

Management of immunosuppressive therapy after functional renal graft failure: Results of a practice survey of French-speaking nephrologists / Gestion du traitement immunosuppresseur après arrêt fonctionnel du greffon rénal : résultats d'une enquête de pratique parmi les néphrologues francophones.

The management of patients with kidney transplant failure (KTF) remains a complex process involving multiple stakeholders. A working group of the Transplantation Commission of the French-speaking Society of Nephrology, Dialysis and Transplantation (SFNDT) conducted a survey on the management of immunosuppressants (IS) after KTF among nephrologists at transplant centres and general nephrologists in France, Switzerland and Belgium between March and June 2023. We analysed 232 replies from 58 nephrologists at transplant centres and 174 general nephrologists, aged 43.6 (+10.6) years. In the first three months following KTF, nephrologists reported discontinuing antimetabolite, calcineurin inhibitor (CNI) and corticosteroid treatment in 83%, 39.9% and 25.8% of cases respectively. Conversely, some nephrologists reported that they were continuing to use CNI (14%) and corticosteroids (19.1%) on a long-term basis. The patient's comorbidities associated with the discontinuation of IS treatment are cancer and opportunistic infections as KT's complications and presence of diabetes mellitus at KTF, whereas humoral rejection encourages the IS to be maintained. Transplantectomy is proposed by nephrologists most often for graft intolerance syndrome (86.5%), more rarely to discontinue IS (17.6%) or in the absence of plans of new transplantation (9.3%). In multivariate analyses, the presence of a protocol in the centre facilitated the management of IS by the general nephrologists. The management of IS after AFG by French-speaking nephrologists is heterogeneous. Specific prospective studies are needed to establish new best practice recommendations, based on more robust evidence, which could encourage better adherence by nephrologists.

La prise en charge des patients avec un arrêt fonctionnel du greffon rénal (AFG) reste un processus complexe avec de multiples intervenants. Un groupe de travail de la Société francophone de néphrologie, dialyse et transplantation (SFNDT) a conduit une enquête sur la gestion des traitements immunosuppresseurs (IS) après AFG parmi les néphrologues de centres de transplantation et néphrologues généraux en France, Suisse et Belgique francophone entre mars et juin 2023. Nous avons pu analyser 232 réponses de néphrologues (centres de transplantation N = 58 et généraux N = 174) âgés de 43,6 (± 10,6) ans. Dans les 3 premiers mois suivant l'AFG, les néphrologues déclarent interrompre le traitement par antimétabolites (83 %), inhibiteurs de la calcineurine (ICN) (39,9 %) et corticoïdes (25,8 %). À l'inverse, certains déclarent maintenir les ICN (14 %) et les corticoïdes (19,1 %) au long cours en cas de projet de nouvelle transplantation rénale (TR). La survenue de cancer pendant la TR, d'infections opportunistes dans la dernière année de TR ou à l'initiation de la dialyse, et la présence d'un diabète lors de l'AFG sont associées avec l'arrêt du traitement IS alors que la perte du greffon par rejet humoral incite à le maintenir. En analyse multivariée, la présence d'un protocole dans le centre facilite la gestion des IS par les néphrologues généraux. Enfin, la transplantectomie est proposée par les néphrologues le plus souvent pour un syndrome d'intolérance du greffon (86,5 %), plus rarement pour interrompre les IS (17,6 %) ou en l'absence de projet de nouvelle TR (9,3 %). La gestion des IS après l'AFG par les néphrologues francophones est hétérogène. Des études prospectives spécifiques sont nécessaires afin de formuler de nouvelles recommandations de bonnes pratiques, reposant sur des données probantes plus robustes, qui pourraient encourager une meilleure adhésion par les néphrologues.