Burden and Management of Multi-Drug Resistant Organism Infections in Solid Organ Transplant Recipients Across the World: A Narrative Review.

Solid organ transplant (SOT) recipients are particularly susceptible to infections caused by multidrug-resistant organisms (MDRO) and are often the first to be affected by an emerging resistant pathogen. Unfortunately, their prevalence and impact on morbidity and mortality according to the type of graft is not systematically reported from high-as well as from low and middle-income countries (HIC and LMIC). Thus, epidemiology on MDRO in SOT recipients could be subjected to reporting bias. In addition, screening practices and diagnostic resources may vary between countries, as well as the availability of new drugs. In this review, we aimed to depict the burden of main Gram-negative MDRO in SOT patients across HIC and LMIC and to provide an overview of current diagnostic and therapeutic resources.

Inter- and intra-individual differences regarding SARS-CoV-2 and influenza vaccination in pediatric kidney transplant recipients: An observational study.

In kidney transplant recipients (KTRs), viral infection can lead to antibody and/or T-cell mediated rejection, resulting in kidney transplant dysfunction. Therefore, it is critical to prevent infections. However, KTRs exhibit suboptimal responses to SARS-CoV-2 and/or influenza vaccines, partly due to immunosuppressant therapy. Inter- and intra-individual differences in the biological responses to vaccines may also affect patients' antibody production ability. This study included KTRs who received an messenger RNA SARS-CoV-2 vaccine (3 doses), and an inactivated quadrivalent influenza vaccine (1 or 2 doses). We measured the patients' total antibody titers against SARS-CoV-2 spike antigen, and hemagglutination inhibition (HI) titers against influenza A/H1N1, A/H3N2, B/Yamagata, and B/Victoria. Five patients were eligible for this study. Of these 5 KTRs, two produced anti-SARS-CoV-2 spike antibody titers to a seroprotective level, and also produced HI titers against A/H1N1 to a seroprotective level. Another 2 KTRs did not produce seroprotective anti-SARS-CoV-2 antibody titers, but produced seroprotective HI titers against A/H1N1. The remaining KTR produced a seroprotective anti-SARS-CoV-2 antibody titer, but did not produce a seroprotective HI titer against A/H1N1. The 2 KTRs who did not produce seroprotective anti-SARS-CoV-2 antibody titers following vaccination, later developed COVID-19, and this infection increased their titers over the seroprotective level. This study demonstrated that inter- and intra-individual differences in biological responses to vaccines should be considered in pediatric KTRs, in addition to immunosuppressant effects. Personalized regimens, such as augmented or booster doses of vaccines, could potentially improve the vaccination efficacy against SARS-CoV-2 and influenza.

Chronological and Geographical Variations in the Incidence and Acceptance of COVID-19-Positive Donors and Outcomes Among Abdominal Transplant Patients.

INTRODUCTION: Given the importance of understanding COVID-19-positive donor incidence and acceptance, we characterize chronological and geographic variations in COVID-19 incidence relative to COVID-19-positive donor acceptance. METHODS: Data on deceased donors and recipients of liver and kidney transplants were obtained from the UNOS database between 2020 and 2023. Hierarchical cluster analysis was used to assess trends in COVID-19-positive donor incidence. Posttransplant graft and patient survival were assessed using Kaplan-Meier curves. RESULTS: From among 38 429 deceased donors, 1517 were COVID-19 positive. Fewer kidneys (72.4% vs. 76.5%, p < 0.001) and livers (56.4% vs. 62.0%, p < 0.001) were used from COVID-19-positive donors versus COVID-19-negative donors. Areas characterized by steadily increased COVID-19 donor incidence exhibit the highest transplantation acceptance rates (92.33%), followed by intermediate (84.62%) and rapidly increased (80.00%) COVID-19 incidence areas (p = 0.016). Posttransplant graft and patient survival was comparable among recipients, irrespective of donor COVID-19 status. CONCLUSIONS: Regions experiencing heightened rates of COVID-19-positive donors are associated with decreased acceptance of liver and kidney transplantation. Similar graft and patient survival is noted among recipients, irrespective of donor COVID-19 status. These findings emphasize the need for adaptive practices and unified medical consensus in navigating a dynamic pandemic.

Effect of COVID-19 on Thrombosis Incidence and Patient Prognosis in Kidney Transplant Recipients.

BACKGROUND Thrombosis poses a grave threat to patients undergoing kidney transplants, with a heightened risk of mortality. While previous studies have established a link between COVID-19 and thrombosis, the specific association between COVID-19 and thrombosis in this patient population remains unexplored. MATERIAL AND METHODS We conducted a retrospective analysis utilizing data from 394 individuals who underwent kidney transplantation within the period of September 1, 2015, to April 1, 2023. To evaluate overall survival, we employed Kaplan-Meier analysis and utilized a logistic regression model for risk analysis. Furthermore, we developed a prediction model and assessed its accuracy through calibration curves. RESULTS Out of the 394 patients included in our study, a total of 51 individuals experienced thrombosis, resulting in 2 deaths. Our analysis revealed that COVID-19 infection significantly increased the risk of thrombosis (odds ratio [OR] 8.60, 95% confidence interval 3.13-24.74, P<0.01). Additionally, the use of cyclosporine was found to elevate the risk of death (OR 20.86, 95% CI 7.93-59.24, P<0.01) according to multifactorial analysis. Logistic models were employed to screen variables, and predictive models were constructed based on the presence of COVID-19 infection and the usage of cyclosporine. A nomogram was developed, demonstrating promising accuracy in estimating the risk of thrombosis during internal validation, with a corrected C-index of 0.869. CONCLUSIONS Our study suggests that both COVID-19 infection and the use of cyclosporine can serve as reliable predictors of thrombosis risk in patients undergoing renal transplantation. Furthermore, we developed a mortality risk prediction model based on COVID-19 in assessing thrombosis.

Bidirectional transfer of human cytomegalovirus strains in donor and recipient seropositive lung transplant patients.

Donor and recipient human cytomegalovirus (HCMV) seropositive (D+R+) lung transplant recipients (LTRs) often harbor multiple strains of HCMV, likely due to transmitted donor (D) strains and reactivated recipient (R) strains. To date, the extent and timely occurrence of each likely source in shaping the post-transplantation (post-Tx) strain population is unknown. Here, we deciphered the D and R origin of the post-Tx HCMV strain composition in blood, bronchoalveolar lavage (BAL), and CD45+ BAL cell subsets. We investigated either D and/or R formalin-fixed paraffin-embedded blocks or fresh D lung tissue from four D+R+ LTRs obtained before transplantation. HCMV strains were characterized by short amplicon deep sequencing. In two LTRs, we show that the transplanted lung is reseeded by R strains within the first 6 months after transplantation, likely by infiltrating CD14+ CD163+/- alveolar macrophages. In three LTRs, we demonstrate both rapid D-strain dissemination and persistence in the transplanted lung for >1 year post-Tx. Broad inter-host diversity contrasts with intra-host genotype sequence stability upon transmission, during follow-up and across compartments. In D+R+ LTRs, HCMV strains of both, D and R origin can emerge first and dominate long-term in subsequent episodes of infection, indicating replication of both sources despite pre-existing immunity.

Impact of Recipient and Donor Body Mass Index on Survival Outcomes After Intestinal Transplantation: A United Network for Organ Sharing Database Analysis.

BACKGROUND Long-term patient survival after intestinal transplantation (IT) remains low compared with other organ transplants despite years of advancement in clinical experience. While patients with extremely high or low body mass index (BMI) are often considered ineligible for IT, the impact of BMI on post-transplant IT survival remains understudied. MATERIAL AND METHODS Using the United Network for Organ Sharing Standard Transplant database, we conducted a retrospective cohort study on patients who underwent IT between April 11, 1994, and September 29, 2021. We assessed the association of recipient and donor BMI at transplant with post-transplant mortality using Kaplan-Meier survival curves and univariate and multivariate Cox regression analyses. RESULTS A total of 1541 patients were included in our final sample. Of these patients, 806 were females (52.5%) and most were in the normal-weight BMI subgroup (54.2%). Obese class II (mean; 36.8±10.92 years) and underweight patients (mean; 37.6±13.37 years) were significantly younger than patients in other BMI categories. The adjusted multivariate model demonstrated an increased risk of mortality in underweight IT recipients compared to normal-weight IT recipients (aHR=1.25, 95% confidence interval [CI], 1.02-1.54; P=0.032).There was no significant association between donor BMI categories and survival in IT recipients. CONCLUSIONS Recipient BMI below normal is associated with an increased risk of mortality after intestinal transplantation and represents a potentially modifiable patient characteristic to improve survival outcomes.

Longitudinal monitoring of Torque Teno virus DNAemia in kidney transplant recipients correlates with long-term complications of inadequate immunosuppression.

Optimization of individual immunosuppression, which reduces the risks of both graft loss and patients' death, is considered the best approach to improve long-term outcomes of renal transplantation. Torque Teno Virus (TTV) DNAemia has emerged as a potential biomarker reflecting the depth of therapeutic immunosuppression during the initial year post-transplantation. However, its efficacy in long-term monitoring remains uncertain. In a cohort study involving 34 stable kidney transplant recipients and 124 healthy volunteers, we established lower and upper TTV DNAemia thresholds (3.75-5.1 log10 cp/mL) correlating with T-cell activatability, antibody response against flu vaccine, and risk for subsequent serious infections or cancer over 50 months. Validation in an independent cohort of 92 recipients confirmed that maintaining TTV DNAemia within this range in >50% of follow-up time points was associated with reduced risks of complications due to inadequate immunosuppression, including de novo DSA, biopsy-proven antibody-mediated rejection, graft loss, infections, or cancer. Multivariate analysis highlighted "in-target" TTV DNAemia as the sole independent variable significantly linked to decreased risk for long-term complications due to inadequate immunosuppression (odds ratio [OR]: 0.27 [0.09-0.77]; p = 0.019). Our data suggest that the longitudinal monitoring of TTV DNAemia in kidney transplant recipients could help preventing the long-term complications due to inadequate immunosuppression.

TTV and CMV viral load dynamics: Which emerges first during immunosuppression?

Novel biomarkers reflecting the degree of immunosuppression in transplant patients are required to ensure eventual personalized equilibrium between rejection and infection risks. With the above aim, Torque Teno Virus (TTV) viremia was precisely examined in a large cohort of transplanted immunocompromised patients (192 hematological and 60 solid organ transplant recipients) being monitored for Cytomegalovirus reactivation. TTV load was measured in 2612 plasma samples from 448 patients. The results revealed a significant increase in TTV viral load approximately 14 days following CMV reactivation/infection in solid organ transplant (SOT) patients. No recognizable difference in TTV load was noted among hematological patients during the entire timeframe analyzed. Furthermore, a temporal gap of approximately 30 days was noted between the viral load peaks reached by the two viruses, with Cytomegalovirus (CMV) preceding TTV. It was not possible to establish a correlation between CMV reactivation/infection and TTV viremia in hematological patients. On the other hand, the SOT patient cohort allowed us to analyze viral kinetics and draw intriguing conclusions. Taken together, the data suggest, to our knowledge for the first time, that CMV infection itself could potentially cause an increase in TTV load in the peripheral blood of patients undergoing immunosuppressive therapy.

Self-Management Using eHealth Technologies for Liver Transplant Recipients: Scoping Review.

BACKGROUND: Liver transplantation has become increasingly common as a last-resort treatment for end-stage liver diseases and liver cancer, with continually improving success rates and long-term survival rates. Nevertheless, liver transplant recipients face lifelong challenges in self-management, including immunosuppressant therapy, lifestyle adjustments, and navigating complex health care systems. eHealth technologies hold the potential to aid and optimize self-management outcomes, but their adoption has been slow in this population due to the complexity of post-liver transplant management. OBJECTIVE: This study aims to examine the use of eHealth technologies in supporting self-management for liver transplant recipients and identify their benefits and challenges to suggest areas for further research. METHODS: Following the Arksey and O'Malley methodology for scoping reviews, we conducted a systematic search of 5 electronic databases: PubMed, CINAHL, Embase, PsycINFO, and Web of Science. We included studies that (1) examined or implemented eHealth-based self-management, (2) included liver transplant recipients aged ≥18 years, and (3) were published in a peer-reviewed journal. We excluded studies that (1) were case reports, conference abstracts, editorials, or letters; (2) did not focus on the posttransplantation phase; (3) did not focus on self-management; and (4) did not incorporate the concept of eHealth or used technology solely for data collection. The quality of the selected eHealth interventions was evaluated using (1) the Template for Intervention Description and Replication guidelines and checklist and (2) the 5 core self-management skills identified by Lorig and Holman. RESULTS: Of 1461 articles, 15 (1.03%) studies were included in the final analysis. Our findings indicate that eHealth-based self-management strategies for adult liver transplant recipients primarily address lifestyle management, medication adherence, and remote monitoring, highlighting a notable gap in alcohol relapse interventions. The studies used diverse technologies, including mobile apps, videoconferencing, and telehealth platforms, but showed limited integration of decision-making or resource use skills essential for comprehensive self-management. The reviewed studies highlighted the potential of eHealth in enhancing individualized health care, but only a few included collaborative features such as 2-way communication or tailored goal setting. While adherence and feasibility were generally high in many interventions, their effectiveness varied due to diverse methodologies and outcome measures. CONCLUSIONS: This scoping review maps the current literature on eHealth-based self-management support for liver transplant recipients, assessing its potential and challenges. Future studies should focus on developing predictive models and personalized eHealth interventions rooted in patient-generated data, incorporating digital human-to-human interactions to effectively address the complex needs of liver transplant recipients. This review emphasizes the need for future eHealth self-management research to address the digital divide, especially with the aging liver transplant recipient population, and ensure more inclusive studies across diverse ethnicities and regions.

Optimizing Quality of Life in Kidney Transplant Recipients Through Structured Exercise: A Systematic Review and Evidence-Based Guidelines.

With the progress of medicine and the maturity of surgery, the improvement of quality of life (QOL) in kidney transplant patients has gradually attracted widespread attention. There is evidence that exercise training has a beneficial effect on patients with renal transplantation. To discover whether exercise can improve patient QOL, this study collected the existing evidence about the effect of structured exercise training on the QOL of renal transplant recipients. Under the guidance of the 5 steps of evidence-based practice, relevant literature in various resources, from 2000 to 2023, was searched. Using the method of systematic review, a PRISMA table was made, and the studies were screened by inclusion and exclusion criteria. Then, the reports were reviewed and the data were extracted. Finally, 5 qualified randomized controlled trials for exercise training of renal transplant recipients were identified. All 5 studies evaluated the health outcomes of patients' QOL. Through the method of evidence-based practice, it was proven that exercise intervention can improve patient QOL after renal transplantation and accelerate their early postoperative recovery. This study integrates and discusses the evidence related to exercise training and QOL of renal transplant recipients to gain an in-depth understanding of the improvements of exercise on patients' QOL and the shortcomings of current clinical implementation. It provides evidence for medical staff to provide exercise interventions to help these transplant patients recover their health and return to daily life.

A Digital Approach to Improve Infection Screening Among Solid Organ Transplant Candidates.

BACKGROUND: Pretransplant infection screening (IS) of potential organ recipients is essential to optimal outcome of solid organ transplantation (SOT). METHODS: A pre-post study was performed during 2020-2023 to investigate the impact of the STREAM (Solid organ TRansplant stEwArdship and Multidisciplinary approach) intervention to improve IS in SOT. The intervention, performed in 2022, included the implementation of IS through educational meetings, local guidelines, and the availability of a digital screening tool. The objective of the study was the assessment of IS completion, including a list of 17 laboratory tests and the investigation of vaccination status. The reduction of unnecessary tests was also analyzed. The test of proportions and a multilevel multivariate Poisson regression model were used to compare IS completion before and after STREAM. infectious diseases (ID) consultation and urgent evaluation were investigated as predictors of IS completion. RESULTS: A total of 171 patients were enrolled, including liver (44%), heart (32%), and kidney (24%) transplant candidates. Mean age was 56 ± 11 years, and most patients (77%) were males. Ninety-five (56%) patients were included before the intervention and 76 (44%) after STREAM. IS completion increased after STREAM (IRR 1.41, p < 0.001) with significant improvement recorded for seven (39%) IS items. Unnecessary tests decreased by 43% after the intervention. ID consultation (IRR 1.13, p = 0.02) and urgent evaluation (p = 0.68, p < 0.001) were predictors of IS improvement. CONCLUSIONS: STREAM was successful in improving IS completion. Further research is needed to investigate the impact of this intervention on posttransplant infections.

Clinical course, management and outcomes of COVID-19 in HIV-infected renal transplant recipients: A case series.

BACKGROUND: HIV-infected kidney transplant recipients with COVID-19 are at increased risk of acute illness and death owing to their underlying comorbidities and chronic immunosuppression. OBJECTIVES: To describe the incidence, clinical presentation and course of COVID-19, vaccination status, and SARS-CoV-2 antibody positivity rate among HIV-infected-to-HIV-infected kidney transplant recipients in South Africa (SA). METHODS: This retrospective study reports on rates of SARS-CoV-2 infection, COVID-19 and mortality among SA HIV-infected kidney transplant recipients who received organs from HIV-infected donors (HIV positive to HIV positive), before and after vaccination. Patient demographics, clinical presentation, course, management and disease outcomes were analysed. Antibody serology tests were performed between May and September 2022. RESULTS: Among 39 HIV-positive-to-HIV-positive transplant recipients, 11 cases of COVID-19 were diagnosed from March 2020 to September 2022. Six patients (55%) required hospitalisation, of whom 3 were admitted to a high-care unit or intensive care unit. Two patients required mechanical ventilation, and 2 received acute dialysis. One patient was declined access to intensive care. Four patients (10%) died of COVID-19 pneumonia. All the COVID-19-positive patients had at least one comorbidity. Vaccination data were available for 24 patients, of whom 5 had refused SARS-CoV-2 vaccination. SARS-CoV-2 antibody data were available for 20 patients; 4 vaccinated patients had a negative nucleocapsid protein antibody test and a positive spike protein antibody test, suggesting vaccination-acquired immunity. The remaining 16 patients demonstrated immunity that was probably due to COVID infection, and of these, 14 were also vaccinated. Of the 11 COVID-19 cases, only 1 was observed after vaccination. CONCLUSION: In our case series, ~10% of the HIV-positive-to-HIV-positive transplant recipients died of COVID-19 pneumonia. This mortality rate appears higher than figures reported in other transplant cohorts. However, it is likely that the actual number of cases of SARS-CoV-2 infection was much higher, as the study only included polymerase chain reaction-confirmed cases. It remains unclear whether HIV infection, transplant or the combination of the two drives poorer outcomes, and larger studies adjusting for important demographic and biological factors may isolate these effects.

Renal transplant recipient and deceased-donor risk profiles at Wits Donald Gordon Medical Centre, Johannesburg, South Africa: A 9-year review.

BACKGROUND: Renal transplantation is the gold-standard therapy for end-stage renal disease. Decision-making around the acceptance of deceased-donor organs is complex and time sensitive. Risk scoring systems for both donors and recipients attempt to simplify the allocation of renal grafts to the most appropriate recipient. OBJECTIVES: To investigate the role of these transplant risk scores in the South African (SA) setting. METHODS: A total of 188 adult deceased-donor organ referrals over the 9-year period 1 January 2013 - 31 December 2021 were included. The Kidney Donor Risk Index (KDRI) and the UK KDRI were calculated for each donor. Recipients who were allocated these grafts were characterised, and the Hennepin Transplant Risk Score and the Kidney Transplant Morbidity Index (KTMI) were calculated. RESULTS: The median (interquartile range) KDRI was 1.2 (0.9 - 1.6), confirming that low- to average-risk donors were being utilised. Similarly, the median UK KDRI was 0.9 (0.8 - 1.2). Both these scores performed poorly in predicting graft and patient survival, with a C-statistic of 0.5. Renal recipient risk scores also demonstrated low- to average-risk patients being transplanted, with a median Hennepin score of 2 - 4 points and a KTMI of 2 points. These recipient scores predict increased recipient mortality at high scores, albeit with low sensitivity, and were not significantly associated with graft survival. CONCLUSION: Deceased-donor and renal recipient risk scores commonly used internationally performed poorly in predicting graft survival in our cohort, and should be used with caution in the SA setting. A conservative approach to organ donor referral and utilisation as well as renal transplant recipient listing was noted.

Assessment of Posttransplant Bacteremia Caused by Extended-Spectrum Beta-Lactamase-Producing Gram-Negative Bacteria Among Kidney Transplant Recipients.

BACKGROUND: Extended-spectrum beta-lactamase-producing gram-negative rods (ESBL-GNR) are a rising cause of bacteremia in kidney transplant recipients (KT). The study purpose was to examine patient mortality, allograft survival, estimated glomerular filtration rate (eGFR) at the end of 1 year, and readmission rates while looking at treatment strategies among KTs with ESBL-GNR and non-ESBL-GNR bacteremia at our institution. METHODS: This study was a retrospective, cohort analysis of KTs with gram-negative bacteremia from January 1, 2020, to December 31, 2021. The primary outcome of the study was mortality. Patient outcomes were assessed for 365 days after positive blood cultures. RESULTS: The study included 63 patients. Of these, 18 (29%) patients had bacteremia caused by an ESBL-GNR and 45 (71%) patients had bacteremia caused by a non-ESBL-GNR. Patient survival at 90 days was 94% in the ESBL-GNR group and 96% in the non-ESBL-GNR group. Ciprofloxacin was the most common antimicrobial therapy at discharge (68.9%) in the non-ESBL-GNR group whereas ertapenem was the most common in the ESBL-GNR group (44.5%). Median eGFR at discharge was 41 mL/min/1.73 m2 in the ESBL-GNR group and 48 mL/min/1.73 m2 in the non-ESBL-GNR group. Ninety-day readmission occurred in 9 (50%) ESBL-GNR patients and 14 (32%) non-ESBL-GNR patients. None of the above comparisons are statistically significant (p > 0.05). Eleven (61%) ESBL-GNR and 2 (4%) non-ESBL-GNR patients used outpatient parenteral antimicrobial therapy (p < 0.001). CONCLUSIONS: Among KTs with ESBL-GNR bacteremia, no significant difference was detected in mortality or allograft function compared to non-ESBL-GNR bacteremia.

Outcomes of Deceased Donor Kidney Recipients From the Same Donor Based on Donor-Recipient Sex Discordance.

INTRODUCTION: Outcomes of deceased donor kidney transplant (DDKT) recipients from the same donor with donor-recipient sex discordance have been studied with inconsistent results. METHODS: Adult DDKT where both kidneys from the same donor occurred at our center in two different recipients of different sexes were included. Outcomes were analyzed separately for male and female donors, based on the concordance or discordance between donor-recipient sex: Male-male (M-m) versus Male to female (M-f) or vice versa, F-f versus F-m. Acute rejection (AR) and uncensored graft failure were primary outcomes of interest. The univariate and multivariate risks for AR and graft failure were conducted using the Cox proportional hazards model and log-rank tests. RESULTS: A total of 130 donors, 84 male and 46 female fulfilled our selection criteria and were transplanted in 260 recipients. With respect to the concordant groups (M-m or F-f), sex discordance was not significantly associated with the risk of rejection in multivariate analysis (M-f vs. M-m HR 1.15 [0.53-2.53, P = 0.72]; F-m vs. F-f HR 1.77 [0.71-4.39, P = 0.23]). Sex discordance was also not significantly associated with graft failure in multivariate analysis. Interestingly, risk factors for AR differed among male donors and female donors. The higher calculated panel reactive antibodies (cPRA) and nonwhite recipients were at increased risk for AR in F-m, but not in M-f. CONCLUSIONS: Donor-recipient sex discordance was not significantly associated with AR or graft failure. Risk factors for AR may differ across male and female donors.

SARS-CoV-2 Vaccination Rates and Uptake of Tixagevimab-Cilgavimab Among a Cohort of Pediatric Solid Organ Transplant Recipients.

INTRODUCTION: There is a lack of data regarding SARS-CoV-2 vaccination rates and tixagevimab-cilgavimab (TC) uptake among pediatric solid organ transplant recipients. The purpose of our study was to assess these rates. MATERIALS AND METHODS: We reviewed vaccination records of pediatric recipients of heart, kidney, and liver transplants at Mayo Clinic, Rochester, MN, who received a transplant between January 2011 and December 2021. All SARS-CoV-2 vaccines and doses of TC received on or before September 1, 2022, the date of approval of the bivalent SARS-CoV2 vaccine, were included. We also assessed whether patients had been seen by an infectious diseases physician (ID) in the preceding 6 months. RESULTS: Our study included 110 patients: 47 kidney, 36 heart, and 27 liver transplant recipients. All vaccine doses recorded were monovalent SARS-CoV-2 vaccines. Sixty-eight (61.8%) patients received at least one vaccine. This varied by age group, with f of ≥12 years olds, 40.9% of 5-11 year olds and 14.3% of under 5 year olds (p = 0.001). Seven patients (6.4%) were up-to-date (UTD) for age. There was no difference in UTD status by organ type (p = 0.335). Patients who saw ID were significantly more likely to be UTD (13.2% versus 2.8%; p = 0.047). Among those eligible, 14 (18.2%) received TC, with rates not different based on transplanted organ type (p = 0.158) or whether they saw ID (p = 0.273). CONCLUSIONS: Despite the availability of vaccines, nearly 40% of pediatric solid organ transplant recipients remained unvaccinated against SARS-CoV-2 at time of the bivalent vaccine release. Less than a fifth of eligible patients received TC. Strategies to increase uptake of SARS-CoV-2 vaccines as well as adjunctive agents among this vulnerable group should be further explored.

A Randomized Trial Comparing Imlifidase to Plasmapheresis in Kidney Transplant Recipients With Antibody-Mediated Rejection.

BACKGROUND: Antibody-mediated rejection (ABMR) poses a barrier to long-term graft survival and is one of the most challenging events after kidney transplantation. Removing donor specific antibodies (DSA) through therapeutic plasma exchange (PLEX) is a cornerstone of antibody depletion but has inconsistent effects. Imlifidase is a treatment currently utilized for desensitization with near-complete inactivation of DSA both in the intra- and extravascular space. METHODS: This was a 6-month, randomized, open-label, multicenter, multinational trial conducted at 14 transplant centers. Thirty patients were randomized to either imlifidase or PLEX treatment. The primary endpoint was reduction in DSA level during the 5 days following the start of treatment. RESULTS: Despite considerable heterogeneity in the trial population, DSA reduction as defined by the primary endpoint was 97% for imlifidase compared to 42% for PLEX. Additionally, imlifidase reduced DSA to noncomplement fixing levels, whereas PLEX failed to do so. After antibody rebound in the imlifidase arm (circa days 6-12), both arms had similar reductions in DSA. Five allograft losses occurred during the 6 months following the start of ABMR treatment-four within the imlifidase arm (18 patients treated) and one in the PLEX arm (10 patients treated). In terms of clinical efficacy, the Kaplan-Meier estimated graft survival was 78% for imlifidase and 89% for PLEX, with a slightly higher eGFR in the PLEX arm at the end of the trial. The observed adverse events in the trial were as expected, and there were no apparent differences between the arms. CONCLUSION: Imlifidase was safe and well-tolerated in the ABMR population. Despite meeting the primary endpoint of maximum DSA reduction compared to PLEX, the trial was unsuccessful in demonstrating a clinical benefit of imlifidase in this heterogenous ABMR population. TRIAL REGISTRATION: EudraCT number: 2018-000022-66, 2020-004777-49; ClinicalTrials.gov identifier: NCT03897205, NCT04711850.

Intravenous Immunoglobulins Alone for the Desensitization of Lung Transplant Recipients with Preformed Donor Specific Antibodies and Negative Flow Cytometry Crossmatch.

BACKGROUND: The lack of evidence regarding optimal desensitization strategies for lung transplant candidates with preformed donor specific anti-human leukocyte antigen antibodies (DSAs) has led to varying approaches among centers towards this patient group. Our institution's desensitization protocol for recipients with preformed DSAs and negative flow cytometry crossmatch (FCXM) consists of intravenous immunoglobulin (IVIG) as the sole therapy. The study aimed to determine outcomes using this approach. METHODS: This retrospective study included adults who underwent lung-only transplantation for the first time between January 2015 and March 2022 at a single center. We excluded patients with positive or missing FCXM results. Transplant recipients with any DSA ≥ 1000 MFI on latest testing within three months of transplant were considered DSA-positive, while recipients with DSAs <1000 MFI and those without DSAs were assigned to the low-level/negative group. Graft survival (time to death/retransplantation) and chronic lung allograft dysfunction (CLAD)-free times were compared between groups using Cox proportional hazards models. RESULTS: Thirty-six out of 167 eligible patients (22%) were DSA-positive. At least 50% of preformed DSAs had documented clearance (decrease to <1000 MFI) within the first 6 months of transplant. Multivariable Cox regression analyses did not detect a significantly increased risk of graft failure (aHR 1.04 95%CI 0.55-1.97) or chronic lung allograft dysfunction (aHR 0.71 95%CI 0.34-1.52) in DSA-positive patients compared to patients with low-level/negative DSAs. Incidences of antibody-mediated rejection (p = 1.00) and serious thromboembolic events (p = 0.63) did not differ between study groups. CONCLUSION: We describe a single-center experience of administering IVIG alone to lung transplant recipients with preformed DSAs and negative FCXM. Further studies are required to confirm the efficacy of this strategy against other protocols.

Detection of Anti-Strongyloides Antibodies in the Serum of Liver Transplant Recipients: Need of Screening for This Neglected Helminthiasis.

Immunosuppressed patients, particularly transplant recipients, can develop severe strongyloidiasis. This study aimed to detect anti-Strongyloides IgG antibodies in a panel of sera from liver transplant patients. Two techniques were used: ELISA as the initial screening test and Western blotting as a confirmatory test. ELISA reactivity of 10.9% (32/294) was observed. The 40-30 kDa fraction was recognised in 93.7% (30/32) of the patients, resulting in a positivity rate of 10.2%. These data highlight the importance of serological screening for Strongyloides stercoralis infection in liver transplant recipients.