Role of SARS-CoV-2-specific memory B cells promoting immune protection after booster vaccination in solid organ transplantation.

Introduction: Solid organ transplant (SOT) recipients display weak seroconversion and neutralizing antibody (NAb) responses after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination and remain at risk of severe coronavirus disease 2019 (COVID-19). While B-cell memory is the hallmark of serological immunity, its role in driving successful vaccine responses and providing immune protection in SOT patients remains unclear. Methods: We investigated the function and interplay of SARS-CoV-2-specific memory B cells (mBc), different cytokineproducing T cells, and cross-reactive NAb in driving seroconversion and protection against COVID-19 in two cohorts. First, we studied a large cohort of 148 SOT recipients and 32 immunocompetent individuals who underwent several vaccinations. Subsequently, we assessed 25 SOT patients participating in a randomized controlled trial to compare two different immunosuppressive strategies for allowing successful seroconversion and memory-cell responses after booster vaccination. Results: We corroborate previous findings that B- and T-cell memory responses are weaker and more delayed in SOT patients than in immunocompetent (IC) individuals; however, within the SOT cohort, we found that these responses are relatively stronger and more robust in patients not receiving mycophenolate mofetil (MMF)-based therapies. Anti- spike IgG titers strongly correlated with RBD-specific IgG-producing mBc, with both displaying broad viral cross reactivity. Prebooster SARS-CoV-2-specific mBc and IL-2- producing T cells accurately predicted Nab seroconversion (AUC, 0.828) and protection against severe COVID-19. While switching unresponsive SOT patients from calcineurin inhibitors (CNI)/MMF to a low-exposure CNI/mTOR-i regimen favored wider SARS-CoV-2-specific immune responses after a fourth booster vaccination, preformed RBD-specific mBc predicted NAb seroconversion. Discussion: Our study adds new insights into the pathobiology of immune memory and highlights the pivotal role of SARS-CoV-2-specific mBc in promoting immune protection inSOT patients.

Does Antiretroviral Therapy Prevent Human T-Lymphotropic Virus 1 Transmission From a Seropositive Donor to a Kidney Transplant Recipient? A Case Report and Literature Review.

Human T-lymphotropic virus 1 produces a latent infection and disease with poor prognosis. Although its transmission during solid-organ transplant and development of the disease has been described, it is not clear whether antiretroviral treatment could prevent it. We report the first kidney transplant of a donor with human T-lymphotropic virus positivity to a negative recipient who was under antiretroviral treatment without evidence of transmission. We reviewed the literature, which included reports of 55 solid-organ transplant donors with human T-lymphotropic virus positivity to negative recipients, showing high rates of transmission and disease. The benefits of antiretroviral treatment require evaluation in further studies.

Management of cytomegalovirus in adult solid organ transplant patients: GESITRA-IC-SEIMC, CIBERINFEC, and SET recommendations update.

Cytomegalovirus (CMV) infection remains a significant challenge in solid organ transplantation (SOT). The last international consensus guidelines on the management of CMV in SOT were published in 2018, highlighting the need for revision to incorporate recent advances, notably in cell-mediated immunity monitoring, which could alter the current standard of care. A working group including members from the Group for the Study of Infection in Transplantation and the Immunocompromised Host (GESITRA-IC) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) and the Spanish Society of Transplantation (SET), developed consensus-based recommendations for managing CMV infection in SOT recipients. Recommendations were classified based on evidence strength and quality using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The final recommendations were endorsed through a consensus meeting and approved by the expert panel.

Perspectives on donor-derived infections from the Notify Library.

It is impossible to eliminate the potential for transmission of donor-derived infections (DDI) when using medical products of human origin (MPHO). However, a thoughtful and systematic approach to donor evaluation can mitigate the risk. Prevention is a key issue, and physicians must maintain a high index of suspicion and remain vigilant in evaluating MPHO donors or recipients, as well as stay current on emerging infections. Biovigilance is the systematic monitoring of serious adverse reactions and events (SARE) that ensures the quality and safety of MPHO in transplantation. The Notify Library with its 2808 references is an available didactic tool that could support physicians in donor or recipient evaluation, inform biovigilance activity, and benefit the international scientific community. It provides free access to a large collection of many different types of SARE, identified mainly through the review of published articles and case reports from national or regional surveillance programs. The Notify Library includes many well-documented records of SARE in the field of DDI, representing a useful tool for assessing SARE associated with transplantation. It is continuously updated with new records, especially when a new type of incident is first reported. All types of described incidents may have educational value while guiding detection, investigation, or risk management. Sharing the lessons learned from these incidents represents an important educational opportunity that can help improve organ donation processes and achieve higher standards of quality and safety.

The value of organ and tissue biovigilance: a cross-sectional analysis.

Introduction: Biovigilance (BV) systems aim to improve the quality and safety of tissues and organs for transplantation. This study describes the Catalan BV system and analyzes its utility. Methods: It is a retrospective analysis of notifications on serious adverse events (SAEs) and reactions (SARs) since the implementation of the BV system (2008 for tissues and 2016 for organs) until 2020. Variables are presented to describe the most common critical steps of the pathway and complications associated with the quality and safety of tissues and organs. Results: A total of 154 and 125 notifications were reported to the Tissue and the Organ BV systems, respectively. Most SAEs were related to unexpected donor diseases and implemented actions were assured on those deemed preventable. Regarding SARs, donor-transmitted infections and malignancies (only organs) were the most common, followed by graft failure (tissues) and process-related (organs). The incidence of SAEs and SARs related to tissue was 3.44‰ and 0.22‰, respectively. The corresponding figures for organs were 31.48‰ and 8.8‰, respectively. Discussion: The analysis of the notifications to the Catalan BV systems has provided useful information about existing risks associated with the quality and safety of tissues and organs, and enabled the implementation of actions targeted to diminish risks and mitigate damage.

Tobramycin Systemic Absorption in Lung Transplant Recipients Treated With Inhaled Tobramycin: A Cohort Study.

Inhaled tobramycin treatment has been associated with nephrotoxicity in some case reports, but limited data are available about serum levels and its possible systemic absorption in lung transplant recipients (LTR). We conducted a single-center, observational and retrospective study of all adult (>18 years old) LTR treated with inhaled tobramycin for at least 3 days between June 2019 and February 2022. Trough serum levels were collected and >2 µg/mL was considered a high drug level. The primary outcome assessed the presence of detectable trough levels, while the secondary outcome focused on the occurrence of acute kidney injury (AKI) in individuals with detectable trough levels. Thirty-four patients, with a median age of 60 years, were enrolled. The primary indications for treatment were donor bronchial aspirate bacterial isolation (18 patients) and tracheobronchitis (15 patients). In total, 28 patients (82%) exhibited detectable serum levels, with 9 (26%) presenting high levels (>2 µg/mL). Furthermore, 9 patients (26%) developed acute kidney injury during the treatment course. Median trough tobramycin levels were significantly elevated in invasively mechanically ventilated patients compared to non-ventilated individuals (2.5 µg/mL vs. 0.48 µg/mL) (p < 0.001). Inhaled tobramycin administration in LTRs, particularly in those requiring invasive mechanical ventilation, may result in substantial systemic absorption.

Multidrug-resistant bacterial infections after liver transplantation: Prevalence, impact, and risk factors.

BACKGROUND & AIMS: Infections by multidrug-resistant bacteria (MDRB) are an increasing healthcare problem worldwide. This study analyzes the incidence, burden, and risk factors associated with MDRB infections after liver transplant(ation) (LT). METHODS: This retrospective, multicenter cohort study included adult patients who underwent LT between January 2017 and January 2020. Risk factors related to pre-LT disease, surgical procedure, and postoperative stay were analyzed. Multivariate logistic regression analysis was performed to identify independent predictors of MDRB infections within the first 90 days after LT. RESULTS: We included 1,045 LT procedures (960 patients) performed at nine centers across Spain. The mean age of our cohort was 56.8 ± 9.3 years; 75.4% (n = 782) were male. Alcohol-related liver disease was the most prevalent underlying etiology (43.2.%, n = 451). Bacterial infections occurred in 432 patients (41.3%) who presented with a total of 679 episodes of infection (respiratory infections, 19.3%; urinary tract infections, 18.5%; bacteremia, 13.2% and cholangitis 11%, among others). MDRB were isolated in 227 LT cases (21.7%) (348 episodes). Enterococcus faecium (22.1%), Escherichia coli (18.4%), and Pseudomonas aeruginosa (15.2%) were the most frequently isolated microorganisms. In multivariate analysis, previous intensive care unit admission (0-3 months before LT), previous MDRB infections (0-3 months before LT), and an increasing number of packed red blood cell units transfused during surgery were identified as independent predictors of MDRB infections. Mortality at 30, 90, 180, and 365 days was significantly higher in patients with MDRB isolates. CONCLUSION: MDRB infections are highly prevalent after LT and have a significant impact on prognosis. Enterococcus faecium is the most frequently isolated multi-resistant microorganism. New pharmacological and surveillance strategies aimed at preventing MDRB infections after LT should be considered for patients with risk factors. IMPACT AND IMPLICATIONS: Multidrug-resistant bacterial infections have a deep impact on morbidity and mortality after liver transplantation. Strategies aimed at improving prophylaxis, early identification, and empirical treatment are paramount. Our study unveiled the prevalence and main risk factors associated with these infections, and demonstrated that gram-positive bacteria, particularly Enterococcus faecium, are frequent in this clinical scenario. These findings provide valuable insights for the development of prophylactic and empirical antibiotic treatment protocols after liver transplantation.

Impact of viral detection in patients with community-acquired pneumonia: An observational cohort study.

PURPOSE: The presence of a respiratory virus in patients with community-acquired pneumonia (CAP) may have an impact on the bacterial etiology and clinical presentation. In this study we aimed to assess the role of viral infection in the bacterial etiology and outcomes of patients with CAP. METHODS: We performed a retrospective study of all adults hospitalized with CAP between November 2017 and October 2018. Patients were classified according to the presence of viral infection. An unvaried and a multivaried analysis were performed to identify variables associated with viral infection and clinical outcomes. RESULTS: Overall 590 patients were included. A microorganism was documented in 375 cases (63.5%). A viral infection was demonstrated in 118 (20%). The main pathogens were Streptococcus pneumoniae (35.8%), Staphylococcus aureus (2.9%) and influenza virus (10.8%). A trend to a higher rate of S. aureus (p=0.06) in patients with viral infection was observed. Patients with viral infection had more often bilateral consolidation patterns (17.8% vs 10.8%, p=0.04), respiratory failure (59.3% vs 42.8%, p=0.001), ICU admission (17.8% vs 7%, p=0.001) and invasive mechanical ventilation (9.3% vs 2.8%, p=0.003). Risk factors for respiratory failure were chronic lung disease, age >65 years, positive blood cultures and viral infection. Influenza, virus but no other respiratory viruses, was associated with respiratory failure (OR, 3.72; 95% CI, 2.06-6.73). CONCLUSIONS: Our study reinforces the idea that co-viral infection has an impact in the clinical presentation of CAP causing a more severe clinical picture. This impact seems to be mainly due to influenza virus infection.

Antifungal prophylaxis with nebulized amphotericin-B in solid-organ transplant recipients with severe COVID-19: a retrospective observational study.

COVID-19-associated pulmonary aspergillosis (CAPA) has emerged as a frequent complication in the intensive care unit (ICU). However, little is known about this life-threatening fungal superinfection in solid organ transplant recipients (SOTRs), including whether targeted anti-mold prophylaxis might be justified in this immunosuppressed population. We performed a multicentric observational retrospective study of all consecutive ICU-admitted COVID-19 SOTRs between August 1, 2020 and December 31, 2021. SOTRs receiving antifungal prophylaxis with nebulized amphotericin-B were compared with those without prophylaxis. CAPA was defined according the ECMM/ISHAM criteria. Sixty-four SOTRs were admitted to ICU for COVID-19 during the study period. One patient received antifungal prophylaxis with isavuconazole and was excluded from the analysis. Of the remaining 63 SOTRs, nineteen (30.2%) received anti-mold prophylaxis with nebulized amphotericin-B. Ten SOTRs who did not receive prophylaxis developed pulmonary mold infections (nine CAPA and one mucormycosis) compared with one who received nebulized amphotericin-B (22.7% vs 5.3%; risk ratio 0.23; 95%CI 0.032-1.68), but with no differences in survival. No severe adverse events related to nebulized amphotericin-B were recorded. SOTRs admitted to ICU with COVID-19 are at high risk for CAPA. However, nebulized amphotericin-B is safe and might reduce the incidence of CAPA in this high-risk population. A randomized clinical trial to confirm these findings is warranted.

Impact of Prophylactic Norfloxacin in Multidrug Resistant Bacterial Infections in the Early Liver Posttransplant Period.

OBJECTIVES: Norfloxacin is indicated as primary or secondary prophylaxis for spontaneous bacterial peritonitis in patients with cirrhosis. A history of spontaneous bacterial peritonitis favors colonization by multidrug-resistant bacteria. Infections caused by these bacteria increase morbidity and mortality after transplant. We investigated prophylactic norfloxacin as a risk factor for multidrug-resistant bacterial infections in the early posttransplant period. MATERIALS AND METHODS: This prospective cohort study included all adult liver recipients in 2 centers between 2015 and 2016. Recipients were classified into 2 groups according to whether or not they received prophylactic norfloxacin pretransplant. Data collection from liver recipients included pretransplant and first month after transplant clinical and microbiological data. Demographic and clinical data of corresponding donors were also collected. RESULTS: We included 157 liver recipients: 54 (34.6%) received norfloxacin and 103 (65.6%) did not received norfloxacin. There were 63 postoperative infections in 47 recipients (29.9%); 17/63 (27%) were multidrug- resistant bacterial infections. The urinary tract was the most commonly affected site (10/17 episodes, 58.8%), and Klebsiella pneumoniae was the microorganism most often isolated (8/17, 47.1%). Incidence of multidrug-resistant bacterial infection was higher in the norfloxacin group (22.2% vs 4.9%; relative risk = 5.6, 95% CI, 1.85-16.89; P = .001).This association was significant after controlling for most confounding factors, including pretransplant vasoactive support (P = .03), Model for End-Stage Liver Disease score (P = .01), previous spontaneous bacterial peritonitis (P = .02), chronic renal impairment (P = .005), number of packed red blood cells (P = .004), use of antilymphocyte globulin as induction (P = .006), and hepatocellular carcinoma (P = .02), but not pre- transplant antibiotic treatment (P = .06). CONCLUSIONS: For recipients who have received prophylactic norfloxacin, clinicians should be aware of the high risk of multidrug-resistant bacterial infections during the first month after liver transplant.

Transplantation of organs from SARS-CoV-2-positive donors: Preliminary experience from Spain.

BACKGROUND: The utilization of non-lung organs from deceased donors with a positive polymerase chain reaction (PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the time of donation can be lifesaving, although the safety of this policy must be assessed. METHODS: This is a nationwide, prospective study, reporting the experience on the utilization of non-lung organs from SARS-CoV-2-positive donors between December 15, 2020 and May 31, 2022 in Spain. RESULTS: A total of 69 patients received a solid organ transplant (41 kidney, 18 liver, 8 heart, and 2 combined liver-kidney) obtained from 32 donors with a positive SARS-CoV-2 PCR at the time of donation (four of them with a cycle threshold value <30). All recipients tested negative for SARS-CoV-2 and were free of coronavirus disease 2019 (COVID-19) symptoms prior to transplantation. Nasopharyngeal swab turned positive for SARS-CoV-2 PCR in 4 (5.8%) recipients at 3, 8, 11, and 20 days after transplantation, though evidence did not support a donor-derived COVID-19. Four kidney recipients lost their grafts and two patients died: one heart recipient due to cardiogenic shock and one combined liver-kidney recipient due to lung hypertension and right heart failure. Graft losses and patient deaths were deemed unrelated to the donor SARS-CoV-2 status by the treating teams. No other adverse reactions were reported. CONCLUSIONS: This preliminary experience supports the safety of the use of organs other than lungs from SARS-CoV-2 PCR-positive donors, in alignment with previous series. However, the impact of SARS-CoV-2 infection upon organ quality should be established in future research.

Hyperthermia Prevents In Vitro and In Vivo Biofilm Formation on Endotracheal Tubes.

There is currently an urgent need to find new strategies to tackle antimicrobial resistance and biofilm-related infections. This study has two aims. First, we evaluated the in vitro efficacy of hyperthermia in preventing biofilm formation on the surfaces of polyvinyl chloride discs. Second, we assessed the in vivo efficacy of hyperthermia in preventing biofilm formation in endotracheal tubes (ETTs) of a rabbit model. For the in vitro studies, nine clinical extensively drug-resistant/multidrug-resistant Gram-negative isolates of Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa and three clinical methicillin-resistant Staphylococcus aureus strains were studied. For biofilm formation, an adhesion step of 30 or 90 min followed by a growth step of 24 h were performed with application of one, two, and three pulses at 42°C for 15 min each pulse after the adhesion step. For the in vivo studies, New Zealand rabbits were intubated with ETTs previously colonized with K. pneumoniae or P. aeruginosa strains, and three pulses at 42°C for 15 min were applied after the adhesion step. The application of three pulses at 42°C for 15 min each pulse was needed to achieve the prevention of the in vitro biofilm formation of 100% of the tested strains. The application of heat pulses in a rabbit intubation model led to biofilm prevention of 85% against two K. pneumoniae strains and 80% against two P. aeruginosa strains compared to the control group. Hyperthermia application through pulses at 42°C could be a new nonantibiotic strategy to prevent biofilm formation in ETTs. IMPORTANCE Biofilm-producing microorganisms are considered medically crucial since they cause 80% of the infections that occur in the human body. Medical devices such as endotracheal tubes (ETTs) can act as a reservoir for pathogens providing the surface to which microorganisms can adhere and cause biofilm-associated infections in critically ill patients. This biofilm has been related with the development of ventilator-associated pneumonia (VAP), with an incidence of 8 to 28%, a mortality rate up to 17% and its associated high extra costs. Although some VAP-preventive measures have been reported, they have not demonstrated a significant reduction of VAP incidence. Therefore, we present a new nonantibiotic strategy based on hyperthermia application to prevent biofilm formation inside ETTs. This technology could reduce VAP incidence, intubation duration, hospital and intensive care unit (ICU) length stays, and mortality rates. Consequently, this could decrease the antibiotics administered and influence the impact of antibiotic resistance in the ICU.

Community-acquired pneumonia in hospitalised patients: changes in aetiology, clinical presentation, and severity outcomes in a 10-year period.

BACKGROUND AND OBJECTIVE: Community-acquired pneumonia (CAP) is a frequent cause of hospitalisation. Several factors, such as pandemics, vaccines and globalisation may lead to changes in epidemiology, clinical presentation, and outcomes of CAP, which oblige to a constant actualisation. We performed this study to analyse how these factors have evolved over a 10-year period. MATERIALS AND METHODS: Patients diagnosed with CAP for two 1-year periods that were 10 years apart (2007-2008 and 2017-2018) were included. We compared microbiological information, clinical data and evolutive outcomes in the two periods. A mortality analysis was performed. RESULTS: 1043 patients were included: 452 during the first period (2007- 2008), and 591 during the second period (2017-2018). Bacterial aetiology did not change during the 10-year period, besides a slight increase in Staphylococcus aureus (0.9% vs 2.9%, p = 0.026). There was a decline in the proportion of bacteraemia in the second period (14.8% vs 9.6%, p = 0.012). The incidence of complicated pleural effusion and septic shock declined too (6.4% vs 3.6%, p = 0.04 and 15.5% vs 6.3%, p < 0.001). Respiratory failure and Intensive care unit (ICU) admission were similar in both periods. Variables independently associated with mortality were age and septic shock. Influenza vaccine was a protective factor against mortality in the second period. CONCLUSIONS: We have not found relevant differences in the bacterial aetiology of CAP over this 10-year period. There has been a decline in septic complications of CAP such as septic shock, bacteraemia, and complicated pleural effusion. Influenza vaccination is an important tool to reduce mortality.KEY MESSAGESThere were no differences in the bacterial pathogens causing CAP among the 10-year study period. There has been a decline in septic complications of CAP such as septic shock, bacteraemia, and complicated pleural effusion.

In Vitro and In Vivo Antimicrobial Activity of Hypochlorous Acid against Drug-Resistant and Biofilm-Producing Strains.

The aims of this study were as follows. First, we determined the antimicrobial efficacy of hypochlorous acid (HClO) against bacterial, fungal, and yeast strains growing planktonically and growing in biofilms. Second, we sought to compare the activity of the combination of daptomycin and HClO versus those of the antimicrobial agents alone for the treatment of experimental catheter-related Staphylococcus epidermidis infection (CRI) using the antibiotic lock technique (ALT) in a rabbit model. HClO was generated through direct electric current (DC) shots at determined amperages and times. For planktonic susceptibility studies, 1 to 3 DC shots of 2, 5, and 10 mA from 0 to 300 s were applied. A DC shot of 20 mA from 0 to 20 min was applied to biofilm-producing strains. Central venous catheters were inserted into New Zealand White rabbits, inoculated with an S. epidermidis strain, and treated with saline solution or ALT using daptomycin (50 mg/mL), HClO (20 mA for 45 min), or daptomycin plus HClO. One hundred percent of the planktonic bacterial, fungal, and yeast strains were killed by applying one DC shot of 2, 5, and 10 mA, respectively. One DC shot of 20 mA for 20 min was sufficient to eradicate 100% of the tested biofilm-producing strains. Daptomycin plus HClO lock therapy showed the highest activity for experimental CRI with S. epidermidis. HClO could be an effective strategy for treating infections caused by extensively drug-resistant or multidrug-resistant and biofilm-producing strains in medical devices and chronic wounds. The results of the ALT using daptomycin plus HClO may be promising. IMPORTANCE Currently, drug-resistant infections are increasing and there are fewer antibiotics available to treat them. Therefore, there is an urgent need to find new antibiotics and nonantimicrobial strategies to treat these infections. We present a new nonantibiotic strategy based on hypochlorous acid generation to treat long-term catheter-related and chronic wounds infections.

Genotypic and Phenotypic Study of Antiviral Resistance Mutations in Refractory Cytomegalovirus Infection.

BACKGROUND: This study describes the genotypic and phenotypic characterization of novel human cytomegalovirus (HCMV) genetic variants of a cohort of 94 clinically resistant HCMV patients. METHODS AND RESULTS: Antiviral-resistant mutations were detected in the UL97, UL54, and UL56 target genes of 25 of 94 (26.6%) patients. The genotype-phenotype correlation study resolved the status of 5 uncharacterized UL54 deoxyribonucleic acid polymerase (G441S, A543V, F460S, R512C, A928T) and 2 UL56 terminase (F345L, P800L) mutations found in clinical isolates. A928T conferred high, triple resistance to ganciclovir, foscarnet, and cidofovir, and A543V had 10-fold reduced susceptibility to cidofovir. Viral growth assays showed G441S, A543V, F345L, and P800L impaired viral growth capacities compared with wild-type AD169 HCMV. Three-dimensional modeling predicted A543V and A928T phenotypes but not R512C, reinforcing the need for individual characterization of mutations by recombinant phenotyping. CONCLUSIONS: Extending mutation databases is crucial to optimize treatments and to improve the assessment of patients with resistant/refractory HCMV infection.

Preliminary Clinical Experience of Molnupiravir to Prevent Progression of COVID-19 in Kidney Transplant Recipients.

BACKGROUND: Recently, different therapeutic lines have been tried in the initial stage of the disease of COVID-19, including remdesivir and molnupiravir. There is scarce evidence on the efficacy and safety of molnupiravir in kidney transplant recipients (KTRs). METHODS: ingle-center prospective cohort study' all adult KTRs diagnosed with COVID-19 and treated with molnupiravir or remdesivir from January to April 2022 were included. RESULTS: Nine KTRs with SARS-CoV-2 (Omicron variant) infection and mild symptoms received molnupiravir in an outpatient basis and were compared with a cohort of similar patients treated with remdesivir (n = 7). Three patients in the molnupiravir cohort were in the early posttransplant period and received a basiliximab (n = 2) or antithymocite globulin-based induction (n = 1). One of the patients had been treated with methylprednisolone bolus and antithymocite globulin for an episode of acute rejection in the previous months. They were all vaccinated with mRNA vaccines' and all but 1 had serological response. Only one of the patients experienced clinical worsening despite molnupiravir treatment and developed pneumonia requiring hospital admission. None of the patients suffered adverse effects attributed to molnupiravir' and no adjustment of tacrolimus dose was needed. None of the patients treated with remdesivir progressed in COVID-19 severity. CONCLUSIONS: Our study suggests that KTRs with SARS-CoV-2 infection under treatment with molnupiravir have a good clinical evolution with a probable lower risk for hospitalization and no adverse effects. At the renal level, molnupiravir was well tolerated, with no evidence of nephrotoxicity secondary to the drug nor interactions with the immunosuppressive therapy.

Positive Polymerase Chain Reaction for SARS-CoV-2 in a Candidate Does Not Always Preclude Liver Transplantation: Case Report and Literature Review.

We report a case of a liver transplant performed in a patient with a history of SARS-CoV-2 infection who presented with a positive polymerase chain reaction test for SARS-CoV-2 on the day of transplant. The transplant procedure was performed without complications, and the patient did not develop symptoms after the initiation of immunosuppression. We also reviewed the literature for similar cases. The emergence of SARS-CoV-2 has forced the medical community to continuously adapt protocols to the current situation. Prudence is needed in immuno- compromised patients, and clinical experience is being built day by day. Thus, a positive polymerase chain reaction test for SARS-CoV-2 in a recipient should not always prevent a liver transplant.

Safety and Effectiveness of Isavuconazole Treatment for Fungal Infections in Solid Organ Transplant Recipients (ISASOT Study).

Isavuconazole (ISA) is an alternative treatment for Aspergillus spp. and other fungal infections, but evidence regarding its use in solid organ transplant recipients (SOTR) is scarce. All SOTR who received ISA for treatment of a fungal infection (FI) at our center from December 2017 to January 2021 were included. The duration of the treatment depended on the type of infection. All patients were followed up to 3 months after treatment. Fifty-three SOTR were included, and the majority (44, 83%) were lung transplant recipients. The most frequently treated FI was tracheobronchitis (25, 46.3%). Aspergillus spp. (43, 81.1%); specially A. flavus (16, 37.2%) and A. fumigatus (12, 27.9%), was the most frequent etiology. Other filamentous fungi including one mucormycosis, and four yeast infections were treated. The median duration of treatment was 81 days (IQR 15-197). Mild gamma-glutamyltransferase elevation was the most frequent adverse event (34%). ISA was prematurely discontinued in six patients (11.3%) due to mild hepatotoxicity (2), fatigue (2), gastrointestinal intolerance (1) and myopathy (1). The mean tacrolimus dose decrease was 30% after starting ISA. Seven patients received ISA with mTOR inhibitors with good tolerability. Two patients developed breakthrough FI (3.8%). Among patients who completed the treatment, 27 (50.9%) showed clinical cure and 15 (34.1%) presented fungal persistence. Three patients (6%) died while on ISA due to FI. ISA was well tolerated and appeared to be an effective treatment for FI in SOTR. IMPORTANCE We describe 53 solid organ transplant recipients treated with isavuconazole for fungal infections. Because its use in clinical practice, there is scarce data of its use in solid organ transplant recipients, where interactions with calcineurin inhibitors and mTOR and adverse drug events have limited the use of other triazoles. To the best of our knowledge, this is the first article describing the safety regarding adverse events and drug interactions of isavuconazole for the treatment of fungal infections in a cohort of solid organ transplant recipients. Also, although this is a noncomparative study, we report some real world effectivity data of these patients, including treatment of non-Aspergillus fungal infections.