Association between humoral serological markers levels and risk of SARS-CoV-2 infection after the primary COVID-19 vaccine course among ANRS0001S COV-POPART cohort participants.

BACKGROUND: We assessed the prognostic value of serological humoral markers measured one month after the last dose of the primary COVID-19 vaccine course for predicting the risk of severe acute respiratory syndrome coronavirus 2 SARS-CoV-2 infection over the following six months in specific populations. METHODS: ANRS0001SCOV-POPART is a French nationwide multicenter prospective observational cohort study assessing the immune response to Covid-19 vaccines routinely administered to 11 subgroups of patients with chronic disease and a control group. Participants from the ANRS0001S COV-POPART were included if they received at least two doses of Covid-19 vaccine for the primary vaccine course, had measurements of anti-Spike, anti-receptor binding domain (RBD) IgG-specific or neutralizing antibodies one month after the end of the primary vaccine course, without being infected by SARS-CoV-2 before the measurement. SARS-CoV-2 infections defined by a positive PCR/antigenic test or seroconversion to detectable anti nucleocapsid antibodies were evaluated until the first COVID-19 booster injection. Cox proportional hazards models taking into account interval-censored data were implemented to estimate the association between each antibody level and the risk of SARS-CoV-2 infection. Predictive performances were evaluated by the area under the receiving operating characteristic curve (AUROC). RESULTS: Two thousand five hundred seventy adults from a specific population and 1,123 from the control group were included. The cumulative probabilities of SARS-CoV-2 infections at five months after serological measurement were 6.0% 95% confidence interval: [5.0; 7.9] and 10.1% 95% confidence interval: [8.3; 11.9], respectively. Higher levels of anti-Spike IgG antibody were associated with a lower risk of SARS-CoV-2 infections in the control group, but not in the specific populations. Among the specific populations, AUROC were 74.5%, 74.9%, and 72.4% for anti-Spike IgG, anti-RBD IgG, and neutralizing antibodies, respectively. AUROC were superior in the specific populations, 82.0%, 81.2%, and 81.4% for anti-Spike IgG, anti-RBD IgG, and neutralizing antibodies, respectively. CONCLUSIONS: Vaccine-induced antibody response after the primary course of Covid-19 infection only moderately discriminated between participants developing a SARS-CoV-2 infection during the Omicron wave. TRIAL REGISTRATION: NCT04824651 (first posted: 2021-04-01).

Very Low Dose Anti-Thymocyte Globulins Versus Basiliximab in Non-Immunized Kidney Transplant Recipients.

The choice between Basiliximab (BSX) or Anti-Thymocyte Globulin (ATG) as induction therapy in non-immunized kidney transplant recipients remains uncertain. Whilst ATG may allow steroid withdrawal and a decrease in tacrolimus, it also increases infectious complications. We investigated outcomes in non-immunized patients receiving a very low dosage of ATG versus BSX as induction. Study outcomes were patient/graft survival, cumulative probabilities of biopsy proven acute rejection (BPAR), infectious episode including CMV and post-transplant diabetes (PTD). Cox, logistic or linear statistical models were used depending on the studied outcome and models were weighted on propensity scores. 100 patients received ATG (mean total dose of 2.0 mg/kg) and 83 received BSX. Maintenance therapy was comparable. Patient and graft survival did not differ between groups, nor did infectious complications. There was a trend for a higher occurrence of a first BPAR in the BSX group (HR at 1.92; 95%CI: [0.77; 4.78]; p = 0.15) with a significantly higher BPAR episodes (17% vs 7.3%, p = 0.01). PTD occurrence was significantly higher in the BSX group (HR at 2.44; 95%CI: [1.09; 5.46]; p = 0.03). Induction with a very low dose of ATG in non-immunized recipients was safe and associated with a lower rate of BPAR and PTD without increasing infectious complications.

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.

Impact of parathyroidectomy on kidney graft function in post-transplant tertiary hyperparathyroidism: a comparative study.

PURPOSE: Parathyroidectomy to treat tertiary hyperparathyroidism (THPT) is now on a par with calcimimetic treatment. The effects of cinacalcet and parathyroidectomy on kidney transplant function remain controversial. The aim of this study was to evaluate kidney transplant function in THPT patients treated either by parathyroidectomy, cinacalcet, or not treated. METHODS: Between 2009 and 2019, 231 patients with functional grafts presenting THPT, defined either by calcaemia superior to 2.5 mmol/L with elevated PTH level or hypercalcaemia with non-adapted PTH level 1 year after kidney transplantation, were included. Hyperparathyroid patients treated by cinacalcet and parathyroidectomy were matched for age, sex, graft rank, and baseline eGFR with cinacalcet-only and untreated patients. Conditional logistic regression models were used to compare eGFR variations 1 year after parathyroidectomy between operated patients and matched controls. Five-year survivals were compared with the Mantel-Cox test. RESULTS: Eleven patients treated with parathyroidectomy and cinacalcet were matched with 16 patients treated by cinacalcet-only and 29 untreated patients. Demographic characteristics were comparable between groups. Estimated odds ratios for eGFR evolution in operated patients compared with cinacalcet-only and untreated patients were 0.92 [95%CI 0.83-1.02] and 0.99 [0.89-1.10] respectively, indicating no significant impairment of eGFR 1 year after surgery. Five-year allograft survival was not significantly impaired in operated patients. CONCLUSIONS: Parathyroidectomy did not appear to substantially alter or improve graft function 1 year after surgery or 5-year allograft survival. It could be hypothesized that in addition to its known benefits, parathyroidectomy can be safely performed vis-à-vis graft function in tertiary hyperparathyroidism.

HLA-D and PLA2R1 risk alleles associate with recurrent primary membranous nephropathy in kidney transplant recipients.

Recurrence of primary membranous nephropathy after transplantation occurs in up to 44% of patients and is driven by PLA2R antibody. Here, we asked whether genetic determinants could improve risk prediction. First, we sequenced PLA2R1 and HLA-D loci in 248 patients with primary membranous nephropathy and identified two independent single nucleotide polymorphisms (SNPs) at risk for primary membranous nephropathy at each locus. These were rs9271188 (intergenic between HLA-DRB1 and HLA-DQA1,) and rs9275086 (intergenic between HLA-DQB1 and HLA-DQA2) at the HLA-D locus along with rs6726925 and rs13018963 at the PLA2R1 locus. Then we investigated whether primary membranous nephropathy at-risk variants were associated with recurrence in a retrospective cohort of 105 donor-recipient pairs and a replication cohort of 40 pairs. Seven SNPs located between HLA-DRB1 and HLA-DQA1 in linkage disequilibrium with rs9271188, and three SNPs in the PLA2R1 region predicted recurrence when presented by the donor, but not when presented by the recipient. The two SNPs in the HLA-D region most strongly associated with recurrence (rs9271705 and rs9271550) were confirmed in the replication cohort. A genetic risk score based on the two best predictors at each locus (rs9271705, rs9271550, rs17830558, and rs3828323) identified a group of patients with high risk of recurrence. Thus, our results suggest that the graft contributes to recurrence of primary membranous nephropathy through the disease susceptibility HLA-D and PLA2R1 SNPs in an autoimmune milieu. Further studies are needed before implementation of genetic testing for these in donor selection.

Higher mortality risk among kidney transplant recipients than among estimated glomerular filtration rate-matched patients with CKD-preliminary results.

BACKGROUND: Although kidney transplantation prolongs survival relative to dialysis, it is associated with a higher death rate than in the general population. The objective of the present study was to assess and compare the risk of mortality and frequency of non-lethal cardiovascular (CV) events in kidney transplant recipients (KTRs) beyond 1 year after successful transplantation versus patients with chronic kidney disease (CKD) using propensity score-matched analysis of estimated glomerular filtration rate (eGFR) and other parameters. METHODS: After propensity score matching, we studied 340 KTRs from the French Données Informatisées et Validées en Transplantation cohort and 605 non-transplant patients with CKD (CKDps) from the French Chronic Kidney Disease-Renal Epidemiology and Information Network cohort. The mean ± standard deviation eGFR was 42 ± 13 and 41 ± 12 mL/min/ 1.73 m2, respectively (P = 0.649). Descriptive data were completed by a survival analysis with Cox regression models. RESULTS: After a median follow-up period of 2.8 years (KTRs 2.0 years, CKDp 2.9 years), 71 deaths were recorded (31 and 40 in the KTR and CKD groups, respectively). Univariate analysis showed that KTRs had a significantly greater risk of mortality than CKDps. In multivariable analysis, KTRs were found to have a 2.7-fold greater risk of mortality [hazard ratio 2.7 (95% confidence interval 1.6-4.7); P = 0.005]. There was no between-group difference concerning the risk of CV events (P = 0.448). CV death rates in KTRs (29.0%) approximated those of CKDps (22.5%), whereas death rates due to infections were higher in KTRs (19.4% versus 10.0%). CONCLUSION: Beyond 1 year after transplantation, KTRs, who possibly had a longer CKD history, had a significantly greater mortality risk than eGFR-matched CKDps. The excess risk was not associated with CV events.

Temporal trends in living kidney donation in France between 2007 and 2017.

BACKGROUND: Long-term studies have demonstrated a slight increased risk for end-stage renal disease (ESRD) for living kidney donors (LKD). In France, living kidney donation doubled within the past 10 years. We investigated the change in characteristics of LKD between 2007 and 2017 and the adequacy of follow-up. METHODS: Data were obtained from the national registry for LKD. We compared characteristics of LKD between two study periods: 2007-11 and 2012-17, and stratified donors by age and relation to recipient. We aggregated four characteristics associated with higher ESRD risk [young age, first-degree relation to recipient, obesity, low glomerular filtration rate (GFR) for age] in a single risk indicator ranging from 0 to 4. RESULTS: We included 3483 donors. The proportion of unrelated donors >56 years of age increased significantly. The proportion of related donors <56 years of age decreased significantly. The body mass index and proportion of obese donors did not change significantly. The proportion of donors with low estimated GFR for age decreased significantly from 5% to 2.2% (P < 0.001). The proportion of donors with adequate follow-up after donation increased from 19.6% to 42.5% (P < 0.001). No donor had a risk indicator equal to 4, and the proportion of donors with a risk indicator equal to 0 increased significantly from 19.2% to 24.9% (P < 0.001). CONCLUSIONS: An increase in living kidney donation in France does not seem to be associated with the selection of donors at higher risk of ESRD and the proportion of donors with adequate annual follow-up significantly increased.

Clinical utility of C-peptide measurement after pancreas transplantation with especial focus on early graft thrombosis.

Since the beginning of our pancreas transplant programme, plasma C-peptide was routinely measured daily during the postoperative period. We aimed to evaluate the clinical interest of the C-peptide in the follow-up of pancreas transplantation with a particular look on early graft failure. From 2000 to 2016, 384 pancreas transplantations were evaluated. We collected and compared C-peptide, glycaemia and adjusted C-peptide (aCP; calculated based on C-peptide, glycaemia and creatininaemia) in patients with and without pancreas failure within 30 days after surgery. Variations of glycaemia, C-peptide and aCP between the day before and the day of failure were also recorded. The difference of aCP was significant during the first week after transplantation between patients with thrombosis and those with functional allograft: 63.2 vs. 26.7 on day 1, P = 0.0003; 61.4 vs. 26.7 on day 3, P < 0.0001; 64.8 vs. 5.7 on day 7, P < 0.0001, respectively. Glycaemia had a median increase of 8% on the day of failure, whereas C-peptide and aCP had, respectively, a median decrease of 88% and 83%. C-peptide monitoring after pancreas transplantation may help to identify graft function and early failure. This sensitive biomarker could allow pre-emptive diagnosis of an early thrombotic event allowing the possibility of rescue interventions.

Living kidney donor evaluation for all candidates with normal estimated GFR for age.

Multiple days assessments are frequent for the evaluation of candidates to living kidney donation, combined with an early GFR estimation (eGFR). Living kidney donation is questionable when eGFR is <90 ml/min/1.73 m2 (KDIGO guidelines) or 80 ml/min/1.73 m2 (most US centres). However, age-related GFR decline results in a lower eGFR for older candidates. That may limit the number of older kidney donors. Yet, continuing the screening with a GFR measure increases the number of eligible donors. We hypothesized that in-depth screening should be proposed to all candidates with a normal eGFR for age. We compared the evolution of eGFR after donation between three groups of predonation eGFR: normal for age (Sage ) higher than 90 or 80 ml/min/1.73 m2 (S90 and S80, respectively); across three age groups (<45, 45-55, >55 years) in a population of 1825 French living kidney donors with a median follow-up of 5.9 years. In donors younger than 45, postdonation eGFR, absolute- and relative-eGFR variation were not different between the three groups. For older donors, postdonation eGFR was higher in S90 than in S80 or Sage but other comparators were identical. Postdonation eGFR slope was comparable between all groups. Our results are in favour of in-depth screening for all candidates to donation with a normal eGFR for age.

Resurgence of BK virus following Covid-19 in kidney transplant recipients.

Kidney transplant recipients have been supposed vulnerable to severe Covid-19 infection, due to their comorbidities and immunosuppressive therapies. Mild-term complications of Covid-19 are currently unknown, especially in this population. Herein, we report two cases of BKV replication after non-severe SARS-CoV-2 infection. The first case was a 59-year-old man, transplanted 3 months ago, with recent history of slight BKV viremia (3.3 log10 DNA copies/ml). Despite strong reduction of maintenance immunosuppression (interruption of mycophenolic acid and important decrease of calcineurin inhibitors), BKV replication largely increased after Covid-19 and viremia persisted at 4.5 log copy/ml few months later. The second case was a 53-year-old woman, transplanted 15 years ago. She had a recent history of BKV cystitis, which resolved with a decrease of MPA dosage. Few weeks after SARS-CoV-2 infection, she presented recurrence of lower urinary tract symptoms. Our reports highlight that SARS-CoV-2 infection, even without severity, could disrupt immune system and particularly lymphocytes, thus leading to viral replication. Monitoring of viral replications after Covid-19 in kidney transplant recipients could permit to confirm these preliminary observations.

The spectrum of kidney function alterations in adolescents with a solitary functioning kidney.

BACKGROUND: A precise assessment of glomerular filtration rate is key to delineate the care of children with a solitary functioning kidney (SFK). Data regarding measured GFR (mGFR) in this population is restricted to a single study of 77 individuals, which suggested that a GFR estimation (eGFR) method based on creatinine and cystatin C (eGFR-CKiD2) performed better than Schwartz's equation (eGFR-Schwartz). METHODS: We measured GFR in 210 consecutive adolescents (7 to 22 years old) with an SFK referred to our institution between 2014 and 2019 and in 43 young candidates for kidney donation (18 to 25 years old). We compared the distribution of mGFR in both groups and determined the factors associated with reduced mGFR in adolescents with an SFK. We further compared different eGFR formulas with mGFR and assessed the association of mGFR and eGFRs with PTH and FGF23, two early indicators of GFR reduction. RESULTS: While adolescents with an SFK had a similar median mGFR to healthy controls (103 ± 24ml/min/1.73m2 vs. 107 ± 12 ml/min/1.73m2), the fraction of individuals with an mGFR below 90 ml/min/1.73m2 was higher in patients with SFK (23% vs. 5% in controls; P = 0.005). Multiple linear regression identified older age, ipsilateral abnormalities of the urinary tract, lack of compensatory hypertrophy, and treated hypertension as independent factors associated with reduced mGFR. A smaller bias using eGFR-Schwartz (95% confidence interval (95%CI): 3 to 7) was revealed when compared to other eGFR. Compared to eGFR-Schwartz, mGFR showed a stronger correlation with PTH (r = 0.04 vs. r = 0.1) and FGF23 (r = 0.03 vs. r = 0.05). CONCLUSION: SFK is not a benign condition, since 20% of the patients display altered kidney function. Our results raise caution regarding the use of the cystatin-based equation. mGFR shows a better ability than eGFR-Schwartz to differentiate patients showing early homeostatic adaptation to GFR reduction.

Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients.

The aim of this study was to estimate the incidence of COVID-19 disease in the French national population of dialysis patients, their course of illness and to identify the risk factors associated with mortality. Our study included all patients on dialysis recorded in the French REIN Registry in April 2020. Clinical characteristics at last follow-up and the evolution of COVID-19 illness severity over time were recorded for diagnosed cases (either suspicious clinical symptoms, characteristic signs on the chest scan or a positive reverse transcription polymerase chain reaction) for SARS-CoV-2. A total of 1,621 infected patients were reported on the REIN registry from March 16th, 2020 to May 4th, 2020. Of these, 344 died. The prevalence of COVID-19 patients varied from less than 1% to 10% between regions. The probability of being a case was higher in males, patients with diabetes, those in need of assistance for transfer or treated at a self-care unit. Dialysis at home was associated with a lower probability of being infected as was being a smoker, a former smoker, having an active malignancy, or peripheral vascular disease. Mortality in diagnosed cases (21%) was associated with the same causes as in the general population. Higher age, hypoalbuminemia and the presence of an ischemic heart disease were statistically independently associated with a higher risk of death. Being treated at a selfcare unit was associated with a lower risk. Thus, our study showed a relatively low frequency of COVID-19 among dialysis patients contrary to what might have been assumed.

Tacrolimus- versus sirolimus-based immunosuppression after simultaneous pancreas and kidney transplantation: 5-year results of a randomized trial.

Tacrolimus, the cornerstone immunosuppression after simultaneous pancreas and -kidney (SPK) transplantation, may exert nephrotoxic and diabetogenic effects. We therefore prospectively compared in an open-label, randomized, monocentric, 5-year follow-up study, a tacrolimus- and a sirolimus-based immunosuppressive regimen. Randomization using the block method allowing a blind allocation was done at the time of surgery. All patients received anti-thymocyte globulin and maintenance therapy with tacrolimus, mycophenolate mofetil, and steroids. At month 3, tacrolimus was continued or replaced by sirolimus. The primary endpoint was kidney and pancreas graft survival at 1 and 5 years. Fifty patients were included in the final analysis in each group. At 1 year, differences for kidney and pancreas graft survival between sirolimus and tacrolimus were 0% (90% confidence interval -4.61% to 4.61%) and 6% (90% confidence interval -6.32% to 18.32%), respectively. There was no difference in renal and pancreas graft survival at 5 years. Thirty-four patients (68%) in the sirolimus group vs three (6%) in the tacrolimus group needed definitive withdrawal of the study drug. Despite noninferiority of sirolimus compared to tacrolimus for kidney and pancreas graft survival, the high rate of sirolimus discontinuation does not favor its use as cornerstone therapy after SPK transplantation (NCT00693446).

Calciphylaxis epidemiology, risk factors, treatment and survival among French chronic kidney disease patients: a case-control study.

BACKGROUND: Calcific Uremic Arteriolopathy (CUA) is a rare disease, causing painful skin ulcers in patients with end stage renal disease. Recommendations for CUA management and treatment are lacking. METHODS: We conducted a retrospective cohort study on CUA cases identified in western France, in order to describe its management and outcome in average clinical practices. Selection was based on the Hayashi diagnosis criteria (2013) extended to patients with eGFR < 30 mL/min/1.73m2. Dialyzed CUA cases were compared with 2 controls, matched for age, gender, region of treatment and time period. RESULTS: Eighty-nine CUA cases were identified between 2006 and 2016, including 19 non dialyzed and 70 dialyzed patients. Females with obesity (55.1%) were predominant. Bone mineral disease abnormalities, inflammation and malnutrition (weight loss, serum albumin decrease) preceded CUA onset for 6 months. The multimodal treatment strategy included wound care (98.9%), antibiotherapy (77.5%), discontinuation of Vitamin K antagonists (VKA) (70.8%) and intravenous sodium thiosulfate (65.2%). 40.4% of the patients died within the year after lesion onset, mainly under palliative care. Surgical debridement, distal CUA, localization to the lower limbs and non calcium-based phosphate binders were associated with better survival. Risks factors of developing CUA among dialysis patients were obesity, VKA, weight loss, serum albumin decrease or high serum phosphate in the 6 months before lesion onset. CONCLUSION: CUA involved mainly obese patients under VKA. Malnutrition and inflammation preceded the onset of skin lesions and could be warning signs among dialysis patients at risk. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02854046, registered August 3, 2016.

Use of Highly Individualized Complement Blockade Has Revolutionized Clinical Outcomes after Kidney Transplantation and Renal Epidemiology of Atypical Hemolytic Uremic Syndrome.

BACKGROUND: Atypical hemolytic uremic syndrome (HUS) is associated with high recurrence rates after kidney transplant, with devastating outcomes. In late 2011, experts in France recommended the use of highly individualized complement blockade-based prophylaxis with eculizumab to prevent post-transplant atypical HUS recurrence throughout the country. METHODS: To evaluate this strategy's effect on kidney transplant prognosis, we conducted a retrospective multicenter study from a large French nationwide registry, enrolling all adult patients with atypical HUS who had undergone complement analysis and a kidney transplant since January 1, 2007. To assess how atypical HUS epidemiology in France in the eculizumab era evolved, we undertook a population-based cohort study that included all adult patients with atypical HUS (n=397) between 2007 and 2016. RESULTS: The first study included 126 kidney transplants performed in 116 patients, 58.7% and 34.1% of which were considered to be at a high and moderate risk of atypical HUS recurrence, respectively. Eculizumab prophylaxis was used in 52 kidney transplants, including 39 at high risk of recurrence. Atypical HUS recurred after 43 (34.1%) of the transplants; in four cases, patients had received eculizumab prophylaxis and in 39 cases they did not. Use of prophylactic eculizumab was independently associated with a significantly reduced risk of recurrence and with significantly longer graft survival. In the second, population-based cohort study, the proportion of transplant recipients among patients with ESKD and atypical HUS sharply increased between 2012 and 2016, from 46.2% to 72.3%, and showed a close correlation with increasing eculizumab use among the transplant recipients. CONCLUSIONS: Results from this observational study are consistent with benefit from eculizumab prophylaxis based on pretransplant risk stratification and support the need for a rigorous randomized trial.

Impact of estimation versus direct measurement of predonation glomerular filtration rate on the eligibility of potential living kidney donors.

While direct measurements of glomerular filtration rate (GFR) provide the most accurate evaluation of pre-donation kidney function, guidelines do not systematically require the use of a reference method. We evaluated whether and to what extent relying upon creatinine-based estimating equations (eGFR) rather than direct measurement of GFR (mGFR) alters the selection of potential living donors. We compared the impact of 4 equations (the MDRD study equation, the CKD-EPI equation, the revised Lund-Malmö equation, and the full age spectrum [FAS] equation) on the evaluation of 2733 potential donors with GFR measured by reference methods. We also considered the impact of using either absolute or age-adapted GFR thresholds. The CKD-EPI and FAS equations had the best performances (P10 of 50.6% and 47.8%; P30 of 94.4% and 93.1%, respectively) and led to the lowest proportion of improperly evaluated candidates. Misclassification was more frequent when GFR adequacy was defined as an absolute threshold of 90 ml/min/1.73m2 as compared to an age-adapted definition (26% and 5%, respectively). Interpretation of eGFR according to an absolute threshold of 90 ml/min/1.73m2 identified 1804 candidates eligible to donate, compared to 2648 when mGFR was interpreted with age-adapted thresholds. We conclude that creatinine-based estimates cannot substitute for direct GFR measurement to evaluate candidates for kidney donation. When reference methods for direct GFR measurement are not available, our data suggest that a strategy based on age-adapted eGFR values estimated with either the CKD-EPI or FAS equation should be preferred.

Benefits of kidney transplantation for a national cohort of patients aged 70 years and older starting renal replacement therapy.

Our objectives were to evaluate kidney transplantation survival benefit in people aged ≥70 who were receiving renal replacement therapy (RRT) and to identify their risk factors for posttransplant mortality. This study included all patients in the national French Renal Epidemiology and Information Network registry who started RRT between 2002 and 2013 at age ≥70. Mortality risk was compared between patients with transplants; on the waiting list; and on dialysis matched for age, gender, comorbidities, and time on dialysis. Of the 41 716 elderly patients starting RRT, 1219 (2.9%) were on the waiting list and 877 (2.1%) underwent transplantation during the follow-up. Until month 3, transplant patients had a risk of death triple that of the wait-listed group. Although the risk was halved at month 9, the perioperative risk was still not offset by month 36. Compared with matched dialysis patients (n = 2183), transplant patients were not at significantly increased perioperative risk and had a lower mortality risk starting at month 3. Risk factors for posttransplant mortality were diabetes, cardiovascular comorbidities, and dialysis duration >2 years. Among older dialysis patients, 20% had neither cardiovascular comorbidity nor diabetes. Systematic early assessment of the eligibility of elderly patients for kidney transplantation is recommended to expand registration to patients with poor survival on dialysis and no cardiovascular comorbidity.

Impact of antiviral prophylaxis in adults Epstein-Barr Virus-seronegative kidney recipients on early and late post-transplantation lymphoproliferative disorder onset: a retrospective cohort study.

Post-transplantation lymphoproliferative disorder (PTLD) pathogenesis is related to EBV infection. Mismatch with the donor (EBV D+/R-) is the main risk factor for both early PTLD (<1 year post-transplantation) and late (>1 year). In these at-risk patients, the role of antiviral prophylaxis for preventing PTLD remains controversial. We analyzed the impact of antiviral drugs given to prevent CMV disease in a monocentric retrospective cohort of 73 adult kidney or kidney-pancreas EBV-seronegative recipients, transplanted between 01/01/2000 and 01/01/2016. Thirty-seven (50.7%, prophylaxis group) received (val-)aciclovir or (val-)ganciclovir for 3-6 months and 36 (49.3%, no-prophylaxis group) received no-prophylaxis. Mean follow-up was 69 ± 7.2 months in the prophylaxis group and 91 ± 10.3 months in the no-prophylaxis group. Monitoring of EBV PCR revealed that prophylaxis delayed primary infection at 100 days (43% vs. 84%, P = 0.02). Early PTLD incidence was not different between groups (4/37 vs. 4/36, P = 0.99). Concerning late events, EBV-related neoplasia incidence was significantly lower in treated patients among whom no cases were observed, while in the no-prophylaxis group 6 cases were reported (P = 0.02). Despite a weak level of evidence our study suggests that antiviral prophylaxis could prevent late onset PTLD.

Clinical and genetic heterogeneity in familial steroid-sensitive nephrotic syndrome.

BACKGROUND: Familial steroid-sensitive nephrotic syndrome (SSNS) is a rare condition. The disease pathophysiology remains elusive. However, bi-allelic mutations in the EMP2 gene were identified, and specific variations in HLA-DQA1 were linked to a high risk of developing the disease. METHODS: Clinical data were analyzed in 59 SSNS families. EMP2 gene was sequenced in families with a potential autosomal recessive (AR) inheritance. Exome sequencing was performed in a subset of 13 families with potential AR inheritance. Two variations in HLA-DQA1 were genotyped in the whole cohort. RESULTS: Transmission was compatible with an AR (n = 33) or autosomal dominant (AD, n = 26) inheritance, assuming that familial SSNS is a monogenic trait. Clinical features did not differ between AR and AD groups. All patients, including primary (n = 7) and secondary steroid resistant nephrotic syndrone (SRNS), (n = 13) were sensitive to additional immunosuppressive therapy. Both HLA-DQA1 variations were found to be highly linked to the disease (OR = 4.34 and OR = 4.89; p < 0.001). Exome sequencing did not reveal any pathogenic mutation, neither did EMP2 sequencing. CONCLUSIONS: Taken together, these results highlight the clinical and genetic heterogeneity in familial SSNS. Clinical findings sustain an immune origin in all patients, whatever the initial steroid-sensitivity. The absence of a variant shared by two families and the HLA-DQA1 variation enrichments suggest a complex mode of inheritance.

Association between daily haemodialysis, access to renal transplantation and patients' survival in France.

AIM: Daily haemodialysis improves patients' quality of life and blood purification, but its effect on survival remains controversial. The aim of this study was to analyze the association between daily haemodialysis and renal transplantation and survival in France. METHODS: This was an observational cohort study based on the French REIN registry. All incident patients ≥18 years old who started daily haemodialysis in France between 2003 and 2012 were included. Using a propensity score, 575 patients on daily haemodialysis were matched with 1696 patients receiving thrice-weekly haemodialysis. Survival analysis was performed using the Cox model. Access to the renal transplant waiting list and renal transplantation were analyzed using the Fine and Gray model. RESULTS: Daily haemodialysis was not independently associated with reduced access to transplant waiting list, whereas, major comorbidities remained associated with restricted waitlisting after multivariate analysis adjusted for confounding factors. After being waitlisted, the cumulative incidence of renal transplantation was lower for the daily haemodialysis than for the thrice-weekly haemodialysis group (SHR = 0.72, 95%CI: 0.56-0.91). The risk of death was significantly higher in the daily haemodialysis group (HRadjusted  = 1.58, 95%CI: 1.4-1.8). Major comorbidities were associated with higher risk of death and lower likelihood of receiving a renal transplant during the follow-up period. CONCLUSION: Our study showed that in France, the likelihood of undergoing renal transplantation after being waitlisted was lower for patients on daily haemodialysis than those on thrice-weekly haemodialysis. Moreover, daily haemodialysis was associated with higher risk of death, even after taking into account age and all major comorbidities.