An extension of the RITUX-ERAH study, multicenter randomized clinical trial comparing rituximab to placebo in acute antibody-mediated rejection after renal transplantation.

The treatment of active antibody-mediated rejection (ABMR) is still a matter of debate, the place of rituximab remaining controversial. The French multicenter double-blind RITUX-ERAH study included 38 patients with ABMR in the first year of renal transplantation. All patients received plasma exchanges, intravenous immunoglobulins, and corticosteroids and were randomly assigned rituximab or placebo infusion at day 5. Additional rituximab infusions were allowed. In the intention-to-treat analysis, 12-month graft survival and renal function were not different between the rituximab and placebo groups. Long-term data are needed to conclude. Evaluation of the 7-year outcomes of the RITUX-ERAH study patients according to the rituximab or placebo treatment received. Eleven patients received placebo and 27 at least one infusion of rituximab. Seven years after ABMR, death-censored kidney allograft survival and renal function were not different between the groups. The evolution of anti-HLA sensitization was similar. There was no statistically significant difference in the incidence of infectious or neoplastic complications, but to be noted, seven cancers developed in six patients treated with rituximab (mean period of 44 months post-ABMR). In this cohort, there was no benefit 7 years after ABMR of rituximab in addition to plasma exchanges, intravenous immunoglobulins, and steroids.

Prognostic Value of the Persistence of C1q-Binding Anti-HLA Antibodies in Acute Antibody-Mediated Rejection in Kidney Transplantation.

BACKGROUND: The differential pathogenicity of anti-HLA donor-specific antibodies (DSAs) is not fully understood. The presence of complement-binding DSAs helps in better defining the prognosis of acute antibody-mediated rejection (ABMR). The evolution of these antibodies after the treatment of ABMR is unknown. METHODS: We included patients from the French multicenter RITUX ERAH study diagnosed with acute ABMR within the first year of renal transplantation, with circulating anti-HLA DSAs and treated randomly by rituximab or placebo (and intravenous immunoglobulins, plasma exchange). We centrally analyzed serum samples at the time of ABMR, 3 and 6 months after ABMR, with anti-HLA DSAs specificities and C1q-binding capacity assessment. RESULTS: Twenty-five patients were included: 68% had C1q-binding DSAs at the time of ABMR. The presence of C1q-binding DSAs was associated with a poorer evolution of chronic glomerulopathy at 6 months (P = 0.036). The persistence of C1q-binding DSAs at 3 and/or 6 months after ABMR was associated with more severe chronic glomerulopathy (P = 0.006), greater C4d score deposition score at 6 months after ABMR (P = 0.008), and graft loss 5 years after ABMR (P = 0.029). C1q-binding capacity was associated with the DSA MFI but 5 C1q-binding DSAs in 4 patients had low MFI values without a prozone effect. CONCLUSION: The presence and persistence of anti-HLA C1q-binding DSAs after ABMR is a detrimental marker, leading to transplant glomerulopathy and graft loss. Assessment of the complement-binding capacities of DSAs could help decide treatment intensification.

Brincidofovir Use after Foscarnet Crystal Nephropathy in a Kidney Transplant Recipient with Multiresistant Cytomegalovirus Infection.

Background. Cytomegalovirus (CMV) antiviral drug resistance constitutes an increasing challenge in transplantation. Foscarnet is usually proposed when resistance for ganciclovir is suspected, but its use is limited by its nephrotoxicity. Case Presentation. We report a case of multiresistant CMV disease in a kidney transplant recipient. Foscarnet was prescribed after ganciclovir treatment failure in a patient with two mutations in the UL97 viral gene. Foscarnet induced biopsy-proven kidney crystal precipitation that resulted in severe acute transplant failure and nephrotic syndrome. Despite a large decrease in immunosuppression, CMV disease was not controlled and a salvage therapy with Brincidofovir (BCV), which is an oral lipid conjugate of cidofovir with limited nephrotoxicity, was attempted. Clinical and virological remission was observed after a 21-day course of BCV, despite mild and reversible liver toxicity. However, a new relapse could not be effectively cured by BCV due to a new mutation in the UL54 gene, which is known to confer resistance to cidofovir. A new course of foscarnet finally resulted in prolonged CMV remission. Herein, we present a review of foscarnet nephropathy cases in solid-organ transplanted patients. Conclusions. This unique case highlights the potential benefit of BCV use during resistant CMV infection, although mutations in the UL54 gene may limit its therapeutic efficacy. These findings need to be confirmed in clinical trials.

One-year Results of the Effects of Rituximab on Acute Antibody-Mediated Rejection in Renal Transplantation: RITUX ERAH, a Multicenter Double-blind Randomized Placebo-controlled Trial.

BACKGROUND: Treatment of acute antibody-mediated rejection (AMR) is based on a combination of plasma exchange (PE), IVIg, corticosteroids (CS), and rituximab, but the place of rituximab is not clearly specified in the absence of randomized trials. METHODS: In this phase III, multicenter, double-blind, placebo-controlled trial, we randomly assigned patients with biopsy-proven AMR to receive rituximab (375 mg/m) or placebo at day 5. All patients received PE, IVIg, and CS. The primary endpoint was a composite of graft loss or no improvement in renal function at day 12. RESULTS: Among the 38 patients included, at 1 year, no deaths occurred, but 1 graft loss occurred in each group. The primary endpoint frequency was 52.6% (10/19) and 57.9% (11/19) in the rituximab and placebo groups, respectively (P = 0.744). Renal function improved in both groups, as soon as day 12 with no difference in serum creatinine level and proteinuria at 1, 3, 6, and 12 months. Supplementary administration of rituximab and total number of IVIg and PE treatments did not differ between the 2 groups. Both groups showed improved histological features of AMR and Banff scores at 1 and 6 months, with no significant difference between groups but with a trend in favor of the rituximab group. Both groups showed decreased mean fluorescence intensity of donor-specific antibodies as soon as day 12, with no significant difference between them but with a trend in favor of the rituximab group at 12 months. CONCLUSIONS: After 1 year of follow-up, we observed no additional effect of rituximab in patients receiving PE, IVIg, and CS for AMR. Nevertheless, our study was underpowered and important differences between groups may have been missed. Complementary trials with long-term follow-up are needed.

Hepatitis E virus of subtype 3i in chronically infected kidney transplant recipients in southeastern France.

Hepatitis E virus (HEV) is a leading cause of waterborne acute hepatitis in developing countries. In Europe, HEV causes a zoonotic disease and is hyperendemic in southern France. Four HEV genotypes (1 to 4) have been defined, and the most used classification divides them into 24 subtypes. Autochthonous European HEV strains belong in majority to genotype 3. Subtypes 3c, 3f, and 3e are representative of the HEV diversity in France. HEV causes chronic hepatitis in solid-organ transplant recipients in Europe, and viral characteristics associated with chronicity are poorly documented. We sequenced 343-nucleotide-long HEV genomic fragments from the serum of eight chronically infected kidney transplant recipients and a near-full-length genome in one case. We identified in four patients (50%) HEV of subtype 3i, not described previously in France. If shorter genomic fragments were used in phylogenetic analyses, these HEV sequences were clustered with open reading frame 2 (ORF2) fragments labeled as subtype 3c. At least five of the eight HEV 3i sequences recovered from humans in our phylogenetic analyses were from chronically infected kidney transplant recipients. These data show that the description of the prevalence and geographical distribution of HEV subtypes may be partially inaccurate and that criteria for classification as 3i and 3c should be clarified. Extended molecular virology analyses are required to improve knowledge of HEV epidemiology and determinants of chronic HEV infection.

Humoral immunity after kidney transplantation: impact of two randomized immunosuppressive protocols.

BACKGROUND: Controlling alloimmune humoral response is a challenge in transplantation. Few studies have evaluated the impact of maintenance immunosuppression on blood humoral parameters. MATERIAL/METHODS: We performed a post-hoc analysis on 307 kidney transplant recipients included in a prospective randomized trial comparing tacrolimus/mycophenolate mofetil (Tac/MMF) vs. cyclosporine/azathioprine (CsA/AZA), both used with antithymocyte globulin induction and steroids. Humoral parameters were analyzed at D0, D15, and M12. RESULTS: IgG, IgA, and IgM levels decreased significantly as soon as D15 in both groups (­35%, ­26%, and ­35% respectively, vs. D0). At M12, although peripheral B-cell counts did not differ between the groups, Tac/MMF regimen was associated with lower IgG, IgA, and IgM levels than CsA/AZA (­5.9%, ­14.6%, and ­34%, respectively). Hypogammaglobulinemia at D15 was not associated with an increased risk of infections during the first year. The proportion of HLA-sensitized patients decreased in the Tac/MMF group (15.9% at D0 and 6.7% at M12, p=0.02) and remained stable in the CsA/AZA group (10.3% at D0 and 8.9% at M12, p=0.5). More patients sensitized at baseline became non-sensitized at M12 with Tac/MMF than with CsA/AZA. CONCLUSIONS: Our results suggest humoral immunosuppression is better with Tac/MMF than with CsA/AZA during the first year of kidney transplantation.

Infection with hepatitis E virus in kidney transplant recipients in southeastern France.

Hepatitis E virus (HEV) is an emerging cause of acute hepatitis in Europe, particularly in southern France, and HEV is a new causative agent of chronic hepatitis and cirrhosis in immunocompromised patients. However, the data regarding HEV infection after kidney transplantation are still scarce with respect to the clinical issues that have been raised, and no study has specifically focused on kidney transplant recipients. This study described the clinical features and outcomes of HEV infections in a cohort of kidney transplant recipients living in southeastern France. The epidemiological, clinical, and virological characteristics of HEV infections diagnosed by PCR over a 53-month period were retrospectively analyzed in a cohort of 1,350 kidney transplant recipients monitored at the Marseille University Hospital. Sixteen HEV infections were diagnosed, all of which were autochthonous and involved genotype 3 viruses (HEV-3). Chronic infections occurred in 80% of these patients and resolved in half of the cases after a median time of 39 months. The rate of HEV clearance was 54% after a decrease in the dose of immunosuppressants. One patient developed liver cirrhosis 14 months after infection and experienced acute rejection after a decrease in the dose of immunosuppressants. Autochthonous HEV-3 infections in kidney transplant recipients progress to chronicity in most cases and might be complicated by early liver cirrhosis. Chronic HEV infection can resolve following the reduction of immunosuppressive therapy, but ribavirin may be required if reduction of the immunosuppressant dose is not associated with HEV clearance or is inappropriate for the patient management.

Autochthonous infections with hepatitis E virus genotype 4, France.

During January-March 2011, diagnoses of hepatitis E virus (HEV) infection increased in Marseille University hospitals in southeastern France. HEV genotype 4, which is described almost exclusively in Asia, was recovered from 2 persons who ate uncooked pork liver sausage. Genetic sequences were 96.7% identical to those recently described in swine in Europe.

A randomized trial with steroids and antithymocyte globulins comparing cyclosporine/azathioprine versus tacrolimus/mycophenolate mofetil (CATM2) in renal transplantation.

BACKGROUND: The best immunosuppressive regimen in benefit-risk ratio in renal transplantation is debated. Nowadays, tacrolimus (Tac) and mycophenolate mofetil (MMF) are considered more efficient than cyclosporine A (CsA) and MMF, but recent studies have challenged this assumption. METHODS: We conducted a monocentric, prospective, open-labeled, randomized, and controlled trial comparing CsA/azathioprine (Aza) versus Tac/MMF in 289 kidney transplant recipients treated with antithymocyte globulins and prednisone. Primary outcome was the number of patients with clinically suspected acute rejection at 1 year. Secondary outcomes were the number of patients with biopsy-proven acute rejection (BPAR), estimated glomerular filtration rate (eGFR), patient and graft survivals, and adverse events at 1 and 3 years. RESULTS: During the first year, 21 patients had clinically suspected acute rejection with CsA/Aza (14.4%) vs. 11 (7.7%) with Tac/MMF (P=0.07). BPAR, including borderline, was more frequent in the CsA/Aza group (14.4%) than in the Tac/MMF group (5.6%; P=0.013). At 1 year, patient and graft survivals were not different, and eGFR was 48±1 in the CsA/Aza group and 53±1 mL/min/1.73 m in the Tac/MMF group (P=0.007). There was no significant difference in diabetes after transplantation (16.8% and 18.8%, respectively). CONCLUSIONS: With antithymocyte globulins and steroids, clinically suspected acute rejections did not differ between CsA/Aza and Tac/MMF arms. Analysis of secondary endpoints showed a lower rate of BPAR, including border line, and a higher eGFR in the Tac/MMF group. CsA/Aza allowed a low acute rejection rate, but Tac/MMF seemed as a better regimen regarding severe secondary outcomes.

Osseous metaplasia in a kidney allograft.

Osseous metaplasia is defined by the presence of heterotopic normal bone tissue in a soft tissue. The bone matrix is associated with osteoblasts, osteoclasts, adipocytes and haematopoietic stem cells. Osseous metaplasia pathophysiology is not well known, but many factors have been incriminated including chronic inflammation and chronic ischaemia. We describe the second case of osseous metaplasia in a kidney allograft. Numerous factors might favour its development including factors linked to transplantation failure environment.

Population pharmacokinetics analysis of mycophenolic acid in adult kidney transplant patients with chronic graft dysfunction.

The aim of this study is to develop a population pharmacokinetic model for total and free mycophenolic acid (MPA) in adult kidney transplant patients with chronic graft dysfunction to understand the contribution of potentially relevant covariates to the inter- and the intraindividual variability of MPA in these patients. Twenty patients received mycophenolate mofetil orally up to 1 g twice daily were enrolled in this prospective pharmacokinetic study. Two hundred twenty-nine total and 257 free concentration-time points were determined using reversed-phase high-performance liquid chromatography/ultraviolet at 21 days and 6 months after initiation of mycophenolate mofetil therapy. Data were analyzed using nonlinear mixed effects modeling. A two-compartment model, with zero-order input and first-order elimination from the central compartment, which combined total and free concentration, was selected. Intersubject variability (ISV) was estimated on the clearance, central volume of distribution, and intercompartmental clearance. Only body weight (WT, kg), occasion, and albumin concentration (mg/L) were kept as covariates in the final model. The population pharmacokinetic parameters were: clearance, 0.27 x WT (L/h) on Day 21 and 0.233 x WT (L/h) at 6 months (ISV, 51%; interoccasion variability, 47%); central distribution volume, 47.6 L (ISV, 31%); intercompartmental clearance, 33.1 L/h (ISV, 128%); peripheral distribution volume, 724 L; duration of infusion, 0.64 (hours), and binding capacity, 0.0012 L/mg. The multiple regression analysis between free and total MPA concentration led to the following model: free MPA concentration (mg/L) = 0.31 + 0.02 total MPA concentration (mg/L) - 0.007 albumin (g/L). The large inter- and intravariability of MPA raises questions about the value of the use of therapeutic monitoring and limited sampling strategies as currently practiced. Moreover, none of the data presented here could justify measurement of free concentration for therapeutic drug monitoring.

Cold ischemia time in renal transplantation is reduced by a timesheet in a French transplant center.

BACKGROUND: Cold ischemia time (CIT) is associated with delayed graft function (DGF) and transplant outcome. Several strategies to reduce CIT have been proposed. We retrospectively analyzed the effect of using a timesheet on CIT in our center. METHODS: In the last 2 years, we have introduced a timesheet to study the course of organ procurement and transplantation during CIT. Results of our 2-year program (121 transplantations) were compared to those in the preceding 2 years (151 transplantations). The timing of each intervention and the influence of national sharing policy and priority recipients were recorded. RESULTS: CIT decreased significantly from 21.45 to 13.27 hours (P<0.0001) and the DGF rate from 34.7 to 20.7% (P=0.011). Usually, human leukocyte antigen typing was done before kidney removal and the recipient was evaluated in the evening or at night for a transplant procedure starting in the morning. Only 1 of 121 transplantations started during the night. The availability of an operating room was the limiting factor. Sharing organs for national priority with a crossmatch having been performed increased CIT twofold (P<0.0001). CONCLUSION: Using a timesheet significantly reduced CIT to the shortest in France. The timesheet is an indicator of motivation and requires the collaboration of all transplantation personnel. It identified certain habits that may be improved to minimize CIT without reorganizing the unit. Providing quicker access to the operating room should further reduce CIT, the key to better graft survival.

Population pharmacokinetics of ceftriaxone and pharmacodynamic considerations in haemodialysed patients.

OBJECTIVES: To determine the pharmacokinetic parameters of ceftriaxone following an infusion in haemodialysed outpatients and to use these parameters for an optimisation of dosing based on pharmacodynamic indices. METHODS: Fifty haemodialysed patients were enrolled in a single-centre, prospective, open-label study. They received short intravenous infusions of ceftriaxone 1 or 2 g every 48 hours for bronchopneumonia immediately after the dialysis session. Total plasma concentrations of ceftriaxone were analysed with a population pharmacokinetic approach using nonlinear mixed-effects modelling. Free drug concentrations were derived from published binding parameters in order to estimate the time when they exceed the minimum inhibitory concentration (MIC). RESULTS: The pharmacokinetics were best described by a two-compartment model. None of the covariates tested (age, bodyweight, height, sex, body mass index, albumin) influenced the pharmacokinetic parameters. The estimated population pharmacokinetic parameters (interindividual variability [percentage of coefficient of variation]) were clearance 0.36 L/h (48%), volume of distribution of the central compartment 4.53 L (47%), intercompartmental clearance 10.8 L/h and volume of distribution of the peripheral compartment 9.54 L (63%). The terminal elimination half-life (t(1/2)beta) from plasma was 27.5 hours. The mean (range) times when the free drug concentration exceeded the MIC (T>MIC) following ceftriaxone 1 g infusion were 60.3 (53.0-67.7) hours and 2.5 (1.0-3.9) hours for the breakpoints 1 and 8 mg/L (based on free drug concentration), respectively. After administration of ceftriaxone 2 g, the T>MIC was 88.5 (78.8-98.3) hours and 17.7 (13.3-22.0) hours for the breakpoints 1 and 8 mg/L, respectively. The simulated free drug concentrations (median, first and third quartile) for 48 and 72 hours following the first dose of ceftriaxone 1g were 1.11, 0.63 and 1.89 mg/L, and 0.63, 0.28 and 1.18 mg/L, respectively. For ceftriaxone 2g infusion, the simulated free concentrations (median, first and third quartile) at 48 and 72 hours were 2.50, 1.40 and 4.52 mg/L, and 1.37, 0.60 and 2.70 mg/L, respectively. CONCLUSIONS: On the basis of decreased clearance in haemodialysed patients, it can be argued that the dose of ceftriaxone should be decreased or the delay between doses should be increased. However, taking into account pharmacodynamic considerations, this study showed that following intravenous administration of ceftriaxone 1 g after each dialysis session, some patients were at risk of achieving a concentration below the MIC (1 mg/L), particularly if the second administration occurred 72 hours after the first dosing. Thus, a dose of ceftriaxone 2 g intravenously is recommended immediately following dialysis, particularly in patients with severe infections or when the dosing interval will be higher than 48 hours.

A three-arm study comparing immediate tacrolimus therapy with antithymocyte globulin induction therapy followed by tacrolimus or cyclosporine A in adult renal transplant recipients.

BACKGROUND: Induction therapy with antithymocyte globulin (ATG) reduces the incidence of acute rejection after transplantation. A study was undertaken to assess the efficacy and safety of ATG induction on tacrolimus-based and cyclosporine A (CsA)-based therapies compared with immediate tacrolimus triple therapy in kidney transplant recipients. METHODS: In a 6-month, open-label, randomized, prospective study conducted in 30 European centers, 555 renal transplant patients were randomly assigned to tacrolimus triple therapy (Tac triple, n=185), ATG induction with tacrolimus (ATG-Tac, n=186), or ATG induction with CsA microemulsion (ATG-CsA, n=184); all were combined with azathioprine and corticosteroids. The primary endpoint was incidence and time to first acute rejection episode confirmed by biopsy. RESULTS: Patient demographics and clinical parameters at baseline were similar. Patient and graft survival rates were similar in all groups. The incidence of clinically apparent acute rejection was significantly higher (P=0.003) for Tac triple (33.0%) compared with ATG-Tac (22.6%) and the incidence for ATG-Tac was significantly lower (P=0.004) than for ATG-CsA (37.0%). The incidences of acute rejection confirmed by biopsy (primary endpoint) were 25.4%, 15.1%, and 21.2% for Tac triple, ATG-Tac, and ATG-CsA, respectively (Tac triple vs. ATG-Tac, P=0.004). The incidences of corticosteroid-resistant acute rejection were 7.0% (Tac triple), 4.8% (ATG-Tac), and 10.9% (ATG-CsA) (ATG-Tac vs. ATG-CsA, P=0.038). In the ATG groups, the incidences of leukopenia, thrombocytopenia, serum sickness, fever, and cytomegalovirus infection were significantly higher (P<0.05). CONCLUSIONS: Acute rejection was significantly lower in the ATG-Tac group compared with the ATG-CsA and Tac triple groups. Significantly more hematologic and infectious adverse events were observed in both ATG induction groups.