Donor-Dependent Variations in Systemic Oxidative Stress and Their Association with One-Year Graft Outcomes in Kidney Transplantation.

INTRODUCTION: Oxidative stress has been implicated in complications after kidney transplantation (KT), including delayed graft function (DGF) and rejection. However, its role in long-term posttransplant outcomes remains unclear. METHODS: We investigated oxidative damage and antioxidant defense dynamics, and their impact on the graft outcomes, in 41 KT recipients categorized by type of donation over 12 months. Oxidative status was determined using OxyScore and AntioxyScore indexes, which comprise several circulating biomarkers of oxidative damage and antioxidant defense. Donor types included donation after brain death (DBD [61.0%]), donation after circulatory death (DCD [26.8%]), and living donation (LD [12.1%]). RESULTS: There was an overall increase in oxidative damage early after transplantation, which was significantly higher in DCD as compared to DBD and LD recipients. The multivariate adjustment confirmed the independent association of OxyScore and type of deceased donation with DGF, donor kidney function, and induction therapy with antithymocyte globulin. There were no differences in terms of antioxidant defense. Lower oxidative damage at day 7 predicted better graft function at 1-year posttransplant only in DBD recipients. CONCLUSION: DCD induced greater short-term oxidative damage after KT, whereas the early levels of oxidative damage were predictive of the graft function 1 year after KT among DBD recipients.

Current management of SARS-CoV-2 infection in solid organ transplant recipients: Experience derived from an ESGICH-ESOT survey.

OBJECTIVE: Solid organ transplant (SOT) recipients have a poorer SARS-CoV-2 vaccine response and higher risk for COVID-19-associated complications. However, there is no consensus on the current management of COVID-19 and data on persistent COVID-19 rates in SOT recipients are lacking. METHODS: An electronic survey concerning the management of COVID-19 in SOT recipients was distributed among all members of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Infections in Compromised Hosts (ESGICH) and of the European Society for Organ Transplantation (ESOT). Four major sections were covered: prevention, early COVID-19, late COVID-19, and persistent COVID-19. We developed a structured questionnaire including eight multiple-choice questions with branching logic in case of positive answers and three open-ended questions related to clinical practice. Questions were asked separately for lung and non-lung transplantation. RESULTS: Thirty-two physicians from 24 different centers participated. Most answers (n = 30) were provided by European physicians. Thirty of 32 (93.75%) physicians managed non-lung transplant recipients and 12 of 32 (33.3%) lung transplant recipients. There was a huge variability in practice regarding the treatment of COVID-19, and particularly noticeable when considering lung and non-lung transplant recipients. Main discordances included the use of nirmatrelvir alone or in combination therapy for early COVID-19, the use of immunomodulatory drugs other than steroids for late COVID-19, and the need for treating asymptomatic viral shedding in persistent COVID-19. There was more similarity in terms of prophylaxis recommendations. CONCLUSION: Despite a low number of respondents, this survey shows that there are many differences on how experts manage SARS-CoV-2 infections in SOT recipients.

Impact of ceftazidime/avibactam versus best available therapy on mortality from infections caused by carbapenemase-producing Enterobacterales (CAVICOR study).

BACKGROUND: Infections caused by carbapenemase-producing Enterobacterales (CPE) are not well represented in pivotal trials with ceftazidime/avibactam. The best strategy for the treatment of these infections is unknown. METHODS: We conducted a multicentre retrospective observational study of patients who received ≥48 h of ceftazidime/avibactam or best available therapy (BAT) for documented CPE infections. The primary outcome was 30 day crude mortality. Secondary outcomes were 21 day clinical response and microbiological response. A multivariate logistic regression model was used to identify factors predictive of 30 day crude mortality. A propensity score to receive treatment with ceftazidime/avibactam was used as a covariate in the analysis. RESULTS: The cohort included 339 patients with CPE infections. Ceftazidime/avibactam treatment was used in 189 (55.8%) patients and 150 (44.2%) received BAT at a median of 2 days after diagnosis of infection. In multivariate analysis, ceftazidime/avibactam treatment was associated with survival (OR 0.41, 95% CI 0.20-0.80; P = 0.01), whereas INCREMENT-CPE scores of >7 points (OR 2.57, 95% CI 1.18-1.5.58; P = 0.01) and SOFA score (OR 1.20, 95% CI 1.08-1.34; P = 0.001) were associated with higher mortality. In patients with INCREMENT-CPE scores of >7 points, ceftazidime/avibactam treatment was associated with lower mortality compared with BAT (16/73, 21.9% versus 23/49, 46.9%; P = 0.004). Ceftazidime/avibactam was also an independent factor of 21 day clinical response (OR 2.43, 95% CI 1.16-5.12; P = 0.02) and microbiological eradication (OR 0.40, 95% CI 0.18-0.85; P = 0.02). CONCLUSIONS: Ceftazidime/avibactam is an effective alternative for the treatment of CPE infections, especially in patients with INCREMENT-CPE scores of >7 points. A randomized controlled trial should confirm these findings.

Cytomegalovirus Management in Solid Organ Transplant Recipients: A Pre-COVID-19 Survey From the Working Group of the European Society for Organ Transplantation.

Infections are leading causes of morbidity/mortality following solid organ transplantation (SOT) and cytomegalovirus (CMV) is among the most frequent pathogens, causing a considerable threat to SOT recipients. A survey was conducted 19 July-31 October 2019 to capture clinical practices about CMV in SOT recipients (e.g., how practices aligned with guidelines, how adequately treatments met patients' needs, and respondents' expectations for future developments). Transplant professionals completed a ∼30-minute online questionnaire: 224 responses were included, representing 160 hospitals and 197 SOT programs (41 countries; 167[83%] European programs). Findings revealed a heterogenous approach to CMV diagnosis and management and, sometimes, significant divergence from international guidelines. Valganciclovir prophylaxis (of variable duration) was administered by 201/224 (90%) respondents in D+/R- SOT and by 40% in R+ cases, with pre-emptive strategies generally reserved for R+ cases: DNA thresholds to initiate treatment ranged across 10-10,000 copies/ml. Ganciclovir-resistant CMV strains were still perceived as major challenges, and tailored treatment was one of the most important unmet needs for CMV management. These findings may help to design studies to evaluate safety and efficacy of new strategies to prevent CMV disease in SOT recipients, and target specific educational activities to harmonize CMV management in this challenging population.

T cell-mediated response to SARS-CoV-2 in liver transplant recipients with prior COVID-19.

Whether immunosuppression impairs severe acute respiratory syndrome coronavirus 2-specific T cell-mediated immunity (SARS-CoV-2-CMI) after liver transplantation (LT) remains unknown. We included 31 LT recipients in whom SARS-CoV-2-CMI was assessed by intracellular cytokine staining (ICS) and interferon (IFN)-γ FluoroSpot assay after a median of 103 days from COVID-19 diagnosis. Serum SARS-CoV-2 IgG antibodies were measured by ELISA. A control group of nontransplant immunocompetent patients were matched (1:1 ratio) by age and time from diagnosis. Post-transplant SARS-CoV-2-CMI was detected by ICS in 90.3% (28/31) of recipients, with higher proportions for IFN-γ-producing CD4+ than CD8+ responses (93.5% versus 83.9%). Positive spike-specific and nucleoprotein-specific responses were found by FluoroSpot in 86.7% (26/30) of recipients each, whereas membrane protein-specific response was present in 83.3% (25/30). An inverse correlation was observed between the number of spike-specific IFN-γ-producing SFUs and time from diagnosis (Spearman's rho: -0.418; p value = .024). Two recipients (6.5%) failed to mount either T cell-mediated or IgG responses. There were no significant differences between LT recipients and nontransplant patients in the magnitude of responses by FluoroSpot to any of the antigens. Most LT recipients mount detectable-but declining over time-SARS-CoV-2-CMI after a median of 3 months from COVID-19, with no meaningful differences with immunocompetent patients.

Impact of late-onset cytomegalovirus infection in the development of cardiac allograft vasculopathy in heart transplant recipients.

BACKGROUND: The impact of late-onset cytomegalovirus (CMV) infection (LOCI) on cardiac allograft vasculopathy (CAV) has yet to be established. METHODS: A retrospective study was performed for patients who had undergone heart transplantation (HT) between January 1995 and October 2017 to analyze epidemiology of LOCI (any positive level of CMV pp65 antigenemia or DNAemia after 100 days, without previous CMV replication) and its association with CAV. Our main hypothesis was that LOCI causes less direct and indirect effects compared to early onset infection (EOCI). RESULTS: Late-onset cytomegalovirus infection developed in 57 of 410 patients (13.9%) in a median time of 4.7 months post-transplant. CAV at 10 years was diagnosed in 31.6% of patients with LOCI, 34.6% with EOCI, and in 19.3% of CMV-uninfected patients. In the multivariate analysis, EOCI was an independent variable for developing CAV (HR 1.8, 95% CI 1.13-2.82, P = .01). Patients with LOCI showed a trend toward a higher risk of CAV, but the difference was not statistically significant (HR 1.7, 95% CI 0.95-3.08, P = .07). In the complementary log-log model, LOCI and EOCI had a similar CAV-free survival, and a higher probability of developing CAV than CMV-uninfected patients (P = .02). CONCLUSIONS: Cytomegalovirus infection after HT may result in the same long-term events regardless of its onset, with a higher risk of developing CAV at 10 years than patients without CMV.

COVID-19 in solid organ transplant recipients: A single-center case series from Spain.

The clinical characteristics, management, and outcome of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after solid organ transplant (SOT) remain unknown. We report our preliminary experience with 18 SOT (kidney [44.4%], liver [33.3%], and heart [22.2%]) recipients diagnosed with COVID-19 by March 23, 2020 at a tertiary-care center at Madrid. Median age at diagnosis was 71.0 ± 12.8 years, and the median interval since transplantation was 9.3 years. Fever (83.3%) and radiographic abnormalities in form of unilateral or bilateral/multifocal consolidations (72.2%) were the most common presentations. Lopinavir/ritonavir (usually associated with hydroxychloroquine) was used in 50.0% of patients and had to be prematurely discontinued in 2 of them. Other antiviral regimens included hydroxychloroquine monotherapy (27.8%) and interferon-ß (16.7%). As of April 4, the case-fatality rate was 27.8% (5/18). After a median follow-up of 18 days from symptom onset, 30.8% (4/13) of survivors developed progressive respiratory failure, 7.7% (1/13) showed stable clinical condition or improvement, and 61.5% (8/13) had been discharged home. C-reactive protein levels at various points were significantly higher among recipients who experienced unfavorable outcome. In conclusion, this frontline report suggests that SARS-CoV-2 infection has a severe course in SOT recipients.

Experience with miltefosine for persistent or relapsing visceral leishmaniasis in solid organ transplant recipients: A case series from Spain.

The incidence of visceral leishmaniasis (VL) after solid organ transplantation (SOT) is increasing. The optimal therapy for post-transplant VL remains unclear, as relapses after liposomal amphotericin B (L-AmB) are common. Miltefosine has been shown to be effective for treating VL in immunocompetent patients, although data in the specific population of SOT recipients are lacking. In the setting of an outbreak of leishmaniasis occurring in Southwest Madrid, we reviewed our experience in 6 SOT recipients with persistent or relapsing VL who received a 28-day course of miltefosine (2.5 mg/kg/day) as salvage therapy. All patients had been treated previously with L-AmB as first-line therapy. The incident episode of VL occurred at a median of 14 months after transplantation. Two patients experienced persistent infection and the remaining 4 had a relapse after a median interval of 168 days since the completion of the course of L-AmB. All the patients had an apparent initial clinical improvement with miltefosine. However, VL relapsed in 3 of them (after a median interval of 46 days), which required retreatment with L-AmB-based regimens. Miltefosine therapy was followed by a prolonged secondary prophylaxis with L-AmB in the only 2 cases with sustained clinical response and ongoing immunosuppression. No adverse effects associated with miltefosine were observed. Albeit limited, our experience suggests that miltefosine monotherapy likely has a limited utility to obtain a long-lasting clinical response in complicated (persistent or relapsing) forms of post-transplant VL, although its role in association with L-AmB-based secondary prophylaxis may merit further investigation.

Caspofungin versus fluconazole as prophylaxis of invasive fungal infection in high-risk liver transplantation recipients: A propensity score analysis.

Targeted prophylaxis has proven to be an efficient strategy in liver transplantation recipients (LTRs). The aim of this study was to compare the effectiveness and safety of caspofungin with that of fluconazole in high-risk (HR) LTRs. Caspofungin and fluconazole were compared in a multicenter, retrospective, cohort study in HR-LTRs in Spain. Outcomes were assessed at 180 days after transplantation. A propensity score approach was applied. During the study period (2005-2012), we analyzed 195 HR-LTRs from 9 hospitals. By type of prophylaxis, 97 patients received caspofungin and 98 received fluconazole. Of a total of 17 (8.7%) global invasive fungal infections (IFIs), breakthrough IFIs accounted for 11 (5.6%) and invasive aspergillosis (IA) accounted for 6 (3.1%). By univariate analysis, no differences were observed in the prevention of global IFIs. However, caspofungin was associated with a significant reduction in the rate of breakthrough IFIs (2.1% versus 9.2%, P = 0.04). In patients requiring dialysis (n = 62), caspofungin significantly reduced the frequency of breakthrough IFIs (P = 0.03). The propensity score analysis confirmed a significant reduction in the frequency of IA in patients receiving caspofungin (absolute risk reduction, 0.06; 95% confidence interval [CI], 0.001-0.11; P = 0.044). Linear regression analysis revealed a significant decrease in blood alanine aminotransferase levels and a significant increase in bilirubin levels after administration of caspofungin. Caspofungin and fluconazole have similar efficacy for the prevention of global IFIs in HR-LTRs in this observational, multicenter cohort study. However, caspofungin was associated with a significant reduction of breakthrough IFIs and, after adjusting for confounders, caspofungin was associated with a lower rate of IA. This benefit is probably more favorable in patients on dialysis. Caspofungin is safe in HR-LTRs, although bilirubin levels may be increased.

Role of mTOR inhibitors for the control of viral infection in solid organ transplant recipients.

Appropriate post-transplant immunosuppressive regimens that avoid acute rejection, while reducing risk of viral reactivation, have been sought, but remain a chimera. Recent evidence suggesting potential regulatory and antiviral effects of mammalian target of rapamycin inhibitors (mTORi) is of great interest. Although the concept of an immunosuppressive drug with antiviral properties is not new, little effort has been made to put the evidence together to assess the management of immunosuppressive therapy in the presence of a viral infection. This review was developed to gather the evidence on antiviral activity of the mTORi against the viruses that most commonly reactivate in adult solid organ recipients: cytomegalovirus (CMV), polyomavirus, Epstein-Barr virus (EBV), human herpesvirus 8 (HHV8), and hepatitis C virus (HCV). A rapid review methodology and evaluation of quality and consistency of evidence based on the GRADE system was used. The existing literature was variable in nature, although indicating a potential advantage of mTORi in CMV, polyomavirus, and HHV8 infection, and a most doubtful relation with EBV and HCV infection. Several recommendations about the management of these infections are presented that can change certain current patterns of immunosuppression and help to improve the prognosis of the direct and indirect effects of viral infection in solid organ recipients.

Varicella-zoster virus (VZV) infection as a possible cause of Ogilvie's syndrome in an immunocompromised host.

We describe an immunodeficient adult with Ogilvie's syndrome preceding a disseminated papulovesicular skin rash in whom varicella-zoster virus infection was demonstrated by PCR assay in cutaneous and colonic biopsy specimens. In view of the significant morbidity and mortality that this condition carries, early and accurate molecular diagnosis and timely treatment are strongly recommended.

Effect of maintenance immunosuppressive drugs on virus pathobiology: evidence and potential mechanisms.

Recent evidence suggesting a potential anti-CMV effect of mTORis is of great interest to the transplant community. However, the concept of an immunosuppressant with antiviral properties is not new, with many accounts of the antiviral properties of several agents over the years. Despite these reports, to date, there has been little effort to collate the evidence into a fuller picture. This manuscript was developed to gather the evidence of antiviral activity of the agents that comprise a typical immunosuppressive regimen against viruses that commonly reactivate following transplant (HHV1 and 2, VZV, EBV, CMV and HHV6, 7, and 8, HCV, HBV, BKV, HIV, HPV, and parvovirus). Appropriate immunosuppressive regimens posttransplant that avoid acute rejection while reducing risk of viral reactivation are also reviewed. The existing literature was disparate in nature, although indicating a possible stimulatory effect of tacrolimus on BKV, potentiation of viral reactivation by steroids, and a potential advantage of mammalian target of rapamycin (mTOR) inhibition in several viral infections, including BKV, HPV, and several herpesviruses.

Kinetics of peripheral blood lymphocyte subpopulations predicts the occurrence of opportunistic infection after kidney transplantation.

Serial monitoring of peripheral blood lymphocyte subpopulations (PBLSs) counts might be useful in predicting post-transplant opportunistic infection (OI) after kidney transplantation (KT). PBLSs were prospectively measured in 304 KT recipients at baseline and post-transplant months 1 and 6. Areas under receiver operating characteristic curves were used to evaluate the accuracy of different subpopulations in predicting the occurrence of overall OI and, specifically, cytomegalovirus (CMV) disease. We separately analyzed patients not receiving (n = 164) or receiving (n = 140) antithymocyte globulin (ATG) as induction therapy. In the non-ATG group, a CD8(+) T-cell count at month 1 <0.100 × 10(3) cells/µl had negative predictive values of 0.84 and 0.86 for the subsequent occurrence of overall OI and CMV disease, respectively. In the multivariate Cox model, a CD8(+) T-cell count <0.100 × 10(3) cells/µl was an independent risk factor for OI (adjusted hazard ratio: 3.55; P-value = 0.002). In the ATG group, a CD4(+) T-cell count at month 1 <0.050 × 10(3) cells/µl showed negative predictive values of 0.92 for the subsequent occurrence of overall OI and CMV disease. PBLSs monitoring effectively identify KT recipients at low risk of OI, providing an opportunity for individualizing post-transplant prophylaxis practices.

Tuberculosis in solid-organ transplant recipients: disease characteristics and outcomes in the current era.

We determined the characteristics of posttransplant tuberculosis and the impact of rifampin-based antituberculosis regimens on outcomes in the current era. Patients comprised 64 transplant recipients with tuberculosis, divided into 2 consecutive cohorts: an earlier cohort (cases occurring from 2003 to 2007) and a later cohort (cases from 2008 to 2011). Patients from the later versus earlier era had tuberculosis develop later after transplant (odds ratio, 1.01; 95% CI, 1.00-1.02; P= .05), were more likely to be liver transplant recipients (odds ratio, 4.52; 95% CI, 1.32-15.53; P= .02), and were more likely to receive tacrolimus-based immunosuppression (odds ratio, 3.24; 95% CI, 1.14-9.19; P= .03). Mortality rate was 10% in the later cohort and 21% in the earlier cohort (P= .20). Rifampin-based treatment was less likely to be used in patients with prior rejection (P= .04). However, neither rejection rate (P= .71) nor mortality (P= .93) after tuberculosis differed between recipients who received rifampin and recipients who did not. Thus, notable changes have occurred in the epidemiological characteristics of tuberculosis in transplant recipients. Overall mortality rate has improved, with about 90% of the patients now surviving after tuberculosis.

Evaluation of the effectiveness and safety of oral vancomycin versus placebo in the prevention of recurrence of Clostridioides difficile infection in patients under systemic antibiotic therapy: a phase III, randomised, double-blind clinical trial.

INTRODUCTION: Clostridioides difficile infection (CDI) is the most prevalent cause of nosocomial bacterial diarrhoea and it is strongly associated with antibiotic use. The recurrence of CDI is a growing medical problem. Data from real-life studies and one open label randomised clinical trial (RCT) suggest that secondary prophylaxis with oral vancomycin (SPV) during subsequent courses of systemic antibiotics is a promising approach for reducing the risk of CDI recurrence. Our aim is to confirm the role of SPV through a double-blind RCT. METHODS AND ANALYSIS: We will perform a phase III, multicentre, placebo-controlled RCT (PREVAN trial) in a 2:1 ratio in favour of SPV (experimental treatment), in four tertiary care hospitals in Spain. Adult patients (≥18 years) with a previous history of CDI in the previous 180 days and with requirement for hospitalisation and systemic antibiotic therapy will be randomly allocated to receive either 125 mg of oral vancomycin or placebo every 6 hours for 10 days. Patients will be followed for 60 days after the end of treatment to verify a reduction in the rate of CDI recurrence in the experimental group. We assume a recurrence rate of 5% in the experimental group versus 25% in the placebo group. Accepting an alpha risk of 0.05 and a beta risk of 0.2 in a two-sided test, 104 subjects will be required in total (68 assigned to the SPV group and 34 to the placebo group). ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Ethic Committee for Research with medicinal products of the University Hospital '12 de Octubre' (AC069/18) and from the Spanish Medicines and Healthcare Product Regulatory Agency (AEMPS, AC069/18), which is valid for all participating centres under existing Spanish legislation. The results will be presented at international meetings and will be made available to patients and funders. TRIAL REGISTRATION NUMBER: NCT05320068.

Hepatitis C and renal transplantation.

PURPOSE OF REVIEW: The purpose of this review is to describe the new insights of hepatitis C virus (HCV) infection and renal transplantation. RECENT FINDINGS: HCV is its most frequent cause of liver disease after transplantation. In the long run, HCV infection can lead to cirrhosis, hepatocarcinoma and death in some patients. As interferon is generally contraindicated after transplantation, the best way to treat patients is before transplantation. Long-term patient and graft survival rates are lower in HCV-positive patients than in HCV-negative graft recipients. HCV infection is an independent risk factor for death and graft loss. Mortality is higher, mainly as a result of cardiovascular complications, liver disease and infections but is lower than in HCV-positive patients on the transplant waiting list. New-onset diabetes after transplantation (NODAT), and HCV-related glomerulonephritis, together with chronic rejection and notably transplant glomerulopathy can contribute to graft failure. Despite this factor, transplantation is the best option for the HCV-positive patient on dialysis. Renal transplantation with kidneys from donors with positive anti-HCV antibodies into HCV RNA-positive recipients seems to be safe in the long term. SUMMARY: Renal transplantation is the therapy of choice for dialysis patients with HCV infection. To improve the results, a careful follow-up in the outpatient clinic for early detection of HCV-related complications is mandatory.

Effectiveness of ceftazidime-avibactam for the treatment of infections due to Pseudomonas aeruginosa.

BACKGROUND: Clinical experience with ceftazidime-avibactam (CAZ-AVI) for treatment of infections due to multidrug or extremely resistant (MDR/XDR) Pseudomonas aeruginosa (P. aeruginosa) is limited. METHODS: A retrospective cohort study was conducted on patients with MDR/XDR P. aeruginosa infections treated with CAZ-AVI. The primary outcome was clinical cure by day 14, evaluated by logistic regression adjusted for the propensity score to receive CAZ-AVI as combination therapy. Secondary outcomes were 30-day all-cause mortality, 90-day recurrence, emerging CAZ-AVI resistance, and safety of therapy. RESULTS: Sixty-one first episodes of MDR/XDR P. aeruginosa infection were included. The most common source was lower respiratory tract infection (34.4%), 14.8% episodes developed bloodstream infection and 50.8% had sepsis at presentation. Ceftazidime-avibactam therapy was initiated at a median of 7.0 (interquartile range [IQR]: 3.5-12.0) days from symptom onset; it was used as combined therapy in 29 (47.5%) episodes. Clinical cure rate by day 14 was 54.1% and predictors of response were days to source control (adjusted odds ratio [aOR]: 0.84; 95% confidence interval [CI]: 0.72-0.98; P = 0.024), days until the initiation of CAZ-AVI therapy (aOR: 0.65; 95% CI: 0.49-0.86; P = 0.003), age (aOR: 1.07; 95% CI: 0.99-1.15; P = 0.066) and CAZ-AVI combination therapy (aOR: 0.02; 95% CI: 0.01-0.38; P = 0.009). Rates of 30-day all-cause mortality and 90-day recurrence were 13.1% and 12.5%, respectively. Emergence of drug resistance to CAZ-AVI was not detected. Treatment-related adverse events occurred in three episodes (4.9%). CONCLUSIONS: CAZ-AVI constitutes a valid alternative for the treatment of infections due to MDR/XDR P. aeruginosa.