Successful double-lung transplantation from a donor previously infected with SARS-CoV-2

COVID-19 infection prevention and control for hospital workers in Indonesia

Introduction

The outbreak of SARS-CoV-2 in 2019 led to a global pandemic, posing unprecedented challenges to healthcare systems, particularly in hospitals.

Purpose

This study explores the intricacies of strategies employed for preventing and controlling COVID-19 in Indonesian hospitals, with a particular focus on the protocols, challenges, and solutions faced by healthcare professionals.

Methods

Using a cross-sectional analysis, we examined 27 hospitals and uncovered disparities in their preparedness levels. During our investigation, we observed the robust implementation of infection prevention measures, which encompassed stringent protocols, adequate ventilation, and proper use of personal protective equipment. However, shortcomings were identified in areas such as surveillance, mental health support, and patient management.

Discussion

This study underscores the importance of addressing these gaps, suggesting tailored interventions, and continuous training for healthcare staff. Effective leadership, positive team dynamics, and adherence to comprehensive policies emerge as pivotal factors. Hospitals should strengthen weak areas, ensure the ethical execution of emergency protocols, and integrate technology for tracking and improving standard operating procedures. By enhancing the knowledge and skills of healthcare workers and maintaining strong management practices, hospitals can optimize their efforts in COVID-19 prevention and control, thereby safeguarding the wellbeing of professionals, patients, and communities.

The value of point-of-care tests for the detection of SARS-CoV-2 RNA or antigen in bronchoalveolar lavage fluid

BACKGROUND

Transmission of SARS-CoV-2 from donor to recipient is a clinically relevant risk for developing severe COVID-19 after lung transplantation (LTx). This risk of iatrogenic transmission can be reduced by timely detection of viral RNA or antigen in samples of bronchoalveolar lavage (BAL) fluid obtained at the time of lung procurement. We aimed to retrospectively evaluate the detection of SARS-CoV-2 RNA or antigen in BAL fluid samples using three point-of-care tests (POCTs).

METHODS

BAL fluid samples came from patients hospitalized in an intensive care unit during the COVID-19 pandemic. These pandemic samples were scored as positive or negative for SARS-CoV-2 by a RT-qPCR comparator assay for orf1ab. Three commercially available POCTs were then evaluated: cobas SARS-CoV-2 & Influenza A/B assay with the cobas Liat RT-qPCR system (Roche Diagnostics), ID NOW COVID-19 and COVID-19 2.0 (Abbott), and SARS-CoV-2 Rapid Antigen Test (RAT) (Roche Diagnostics). Samples from the pre-pandemic era served as negative controls.

RESULTS

We analyzed a total of 98 BAL fluid samples, each from a different patient: 58 positive pandemic samples (orf1ab Ct<38), 20 putatively negative pandemic samples (orf1ab Ct≥38), and 20 pre-pandemic samples. Univariate logistic regression shows that the probability of detection was highest for cobas Liat, followed by ID NOW, and then RAT. Of clinical relevance, cobas Liat detected SARS-CoV-2 RNA in 30 of the 31 positive pandemic samples that were collected within 10 days after RT-qPCR diagnosis of SARS-CoV-2 infection. None of the 20 pre-pandemic samples had a false-positive result for any POCT.

CONCLUSIONS

POCTs enable the detection of SARS-CoV-2 RNA or antigen in BAL fluid samples and may provide additional information to decide if donor lungs are suitable for transplantation. Detection of respiratory pathogens with POCTs at the time of donor lung procurement is a potential strategy to increase safety in LTx by preventing iatrogenic transmission and severe postoperative infections.

Bronchial Stenosis After Lung Transplantation From cDCD Donors Using Simultaneous Abdominal Normothermic Regional Perfusion: A Single-center Experience

BACKGROUND

Controlled donation after circulatory death (cDCD) has increased the number of lung donors significantly. The use of abdominal normothermic regional perfusion (A-NRP) during organ procurement is a common practice in some centers due to its benefits on abdominal grafts. This study aimed to assess whether the use of A-NRP in cDCD increases the frequency of bronchial stenosis in lung transplant (LT) recipients.

METHODS

A single-center, retrospective study including all LTs was performed between January 1, 2015, and August 30, 2022. Airway stenosis was defined as a stricture that leads to clinical/functional worsening requiring the use of invasive monitoring and therapeutic procedures.

RESULTS

A total of 308 LT recipients were included in the study. Seventy-six LT recipients (24.7%) received lungs from cDCD donors using A-NRP during organ procurement. Forty-seven LT recipients (15.3%) developed airway stenosis, with no differences between lung recipients with grafts from cDCD (17.2%) and donation after brain death donors (13.3%; P  = 0.278). A total of 48.9% of recipients showed signs of acute airway ischemia on control bronchoscopy at 2 to 3 wk posttransplant. Acute ischemia was an independent risk factor for airway stenosis development (odds ratio = 2.523 [1.311-4.855], P  = 0.006). The median number of bronchoscopies per patient was 5 (2-9), and 25% of patients needed >8 dilatations. Twenty-three patients underwent endobronchial stenting (50.0%) and each patient needed a median of 1 (1-2) stent.

CONCLUSIONS

Incidence of airway stenosis is not increased in LT recipients with grafts obtained from cDCD donors using A-NRP.

SARS-CoV-2 RNA positive pediatric organ donors: A case report

BACKGROUND

Preliminary evidence suggests that non-lung organ donation from resolved, asymptomatic or mildly symptomatic SARS-CoV-2 infected adults may be safe. However, several biological aspects of SARS-CoV-2 infection differ in children and the risk for transmission and outcomes of recipients from pediatric donors with SARS-CoV-2 infection are not well described.

METHODS

We report two unvaccinated asymptomatic pediatric non-lung organ deceased donors who tested positive for SARS-CoV-2 RNA by RT-PCR. Donor One unexpectedly had SARS-CoV-2 RNA detected in nasopharyngeal swab and plasma specimens at autopsy despite several negative tests (upper and lower respiratory tract) in the days prior to organ recovery. Donor Two had SARS-CoV- 2 RNA detected in multiple nasopharyngeal swabs but not lower respiratory tract specimens (endotracheal aspirate and bronchoalveolar lavage) during routine surveillance prior to organ recovery and was managed with remdesivir and monoclonal antibodies prior to organ recovery.

RESULTS

Two hearts, two livers and four kidneys were successfully transplanted into seven recipients. No donor to recipient transmission of SARS-CoV-2 was observed and graft function of all organs has remained excellent for up to 7 months of followup.

CONCLUSIONS

Due to the persistent gap between organ availability and the number of children waiting for transplants, deceased pediatric patients with non-disseminated SARS-CoV-2 infection, isolated to upper and/or lower respiratory tract, should be considered as potential non-lung organ donors.

Visualising SARS-CoV-2 infection of the lung in deceased COVID-19 patients

BACKGROUND

SARS-CoV-2 is a single-stranded positive-sense RNA virus. Several negative-sense SARS-CoV-2 RNA species, both full-length genomic and subgenomic, are produced transiently during viral replication. Methodologies for rigorously characterising cell tropism and visualising ongoing viral replication at single-cell resolution in histological sections are needed to assess the virological and pathological phenotypes of future SARS-CoV-2 variants. We aimed to provide a robust methodology for examining the human lung, the major target organ of this RNA virus.

METHODS

A prospective cohort study took place at the University Hospitals Leuven in Leuven, Belgium. Lung samples were procured postmortem from 22 patients who died from or with COVID-19. Tissue sections were fluorescently stained with the ultrasensitive single-molecule RNA in situ hybridisation platform of RNAscope combined with immunohistochemistry followed by confocal imaging.

FINDINGS

We visualised perinuclear RNAscope signal for negative-sense SARS-CoV-2 RNA species in ciliated cells of the bronchiolar epithelium of a patient who died with COVID-19 in the hyperacute phase of the infection, and in ciliated cells of a primary culture of human airway epithelium that had been infected experimentally with SARS-CoV-2. In patients who died between 5 and 13 days after diagnosis of the infection, we detected RNAscope signal for positive-sense but not for negative-sense SARS-CoV-2 RNA species in pneumocytes, macrophages, and among debris in the alveoli. SARS-CoV-2 RNA levels decreased after a disease course of 2-3 weeks, concomitant with a histopathological change from exudative to fibroproliferative diffuse alveolar damage. Taken together, our confocal images illustrate the complexities stemming from traditional approaches in the literature to characterise cell tropism and visualise ongoing viral replication solely by the surrogate parameters of nucleocapsid-immunoreactive signal or in situ hybridisation for positive-sense SARS-CoV-2 RNA species.

INTERPRETATION

Confocal imaging of human lung sections stained fluorescently with commercially available RNAscope probes for negative-sense SARS-CoV-2 RNA species enables the visualisation of viral replication at single-cell resolution during the acute phase of the infection in COVID-19. This methodology will be valuable for research on future SARS-CoV-2 variants and other respiratory viruses.

FUNDING

Max Planck Society, Coronafonds UZ/KU Leuven, European Society for Organ Transplantation.

Update on Covid-19: vaccines, timing of transplant after COVID-19 infection and use of positive donors

PURPOSE OF REVIEW

SARS-CoV-2 resulted in a global pandemic that had a chilling effect on transplantation early in the pandemic and continues to result in significant morbidity and mortality of transplant recipients. Over the past 2.5 years, our understanding of the clinical utility of vaccination and mAbs to prevent COVID-19 in solid organ transplant (SOT) recipients has been studied. Likewise, approach to donors and candidates with SARS-CoV-2 has been better understood. This review will attempt to summarize our current understanding of these important COVID-19 topics.

RECENT FINDINGS

Vaccination against SARS-CoV-2 is effective in reducing the risk of severe disease and death among transplant patients. Unfortunately, humoral and, to a lesser extent, cellular immune response to existing COVID-19 vaccines is reduced in SOT recipients compared with healthy controls. Additional doses of vaccine are required to optimize protection of this population and still may be insufficient in those who are highly immunosuppressed, those receiving belatacept, rituximab and other B-cell active mAbs. Until recently, mAbs were options for the prevention of SARS-CoV-2 but are markedly less effective with recent omicron variants. SARS-CoV-2-infected donors can generally be used for nonlung, nonsmall bowel transplants unless they have died of acute severe COVID-19 or COVID-19-associated clotting disorders.

SUMMARY

Our transplant recipients require a three-dose mRNA or adenovirus-vector and one dose of mRNA vaccine to be optimally protected initially; they then need to receive a bivalent booster 2+ months after completing their initial series. Most nonlung, nonsmall bowel donors with SARS-CoV-2 can be utilized as organ donors.

Successful Lung Transplantation From a Donor With Previous Severe COVID-19 Pneumonia

Lungs from donors with previous COVID-19 could become a precious resource if proved safe. So far, only 3 successful lung transplantations from donors with previous mild COVID-19 have been reported. We describe a successful bilateral sequential lung transplantation from a donor who, 10 months before, had developed severe COVID-19 acute respiratory distress syndrome. No donor-derived viral transmission occurred, and 12 months after transplantation, the recipient's lung function is normal. In the presence of normal results of bronchoalveolar lavage and adequate functional and morphologic parameters, even a history of severe COVID-19 acute respiratory distress syndrome might not be considered a contraindication to lung donation.

Successful lung transplantation using an allograft from a COVID-19-recovered donor: a potential role for subgenomic RNA to guide organ utilization

Although the risk of SARS-CoV-2 transmission through lung transplantation from acutely infected donors is high, the risks of virus transmission and long-term lung allograft outcomes are not as well described when using pulmonary organs from COVID-19-recovered donors. We describe successful lung transplantation for a COVID-19-related lung injury using lungs from a COVID-19-recovered donor who was retrospectively found to have detectable genomic SARS-CoV-2 RNA in the lung tissue by multiple highly sensitive assays. However, SARS-CoV-2 subgenomic RNA (sgRNA), a marker of viral replication, was not detectable in the donor respiratory tissues. One year after lung transplantation, the recipient has a good functional status, walking 1 mile several times per week without the need for supplemental oxygen and without any evidence of donor-derived SARS-CoV-2 transmission. Our findings highlight the limitations of current clinical laboratory diagnostic assays in detecting the persistence of SARS-CoV-2 RNA in the lung tissue. The persistence of SARS-CoV-2 RNA in the donor tissue did not appear to represent active viral replication via sgRNA testing and, most importantly, did not negatively impact the allograft outcome in the first year after lung transplantation. sgRNA is easily performed and may be a useful assay for assessing viral infectivity in organs from donors with a recent infection.

Exploring predisposing factors and pathogenesis contributing to injuries of donor lungs

INTRODUCTION

Lung transplantation (LTx) remains the only therapeutic strategy for patients with incurable lung diseases. However, its use has been severely limited by the narrow donor pool and potential concerns of inferior quality of donor lungs, which are more susceptible to external influence than other transplant organs. Multiple insults, including various causes of death and a series of perimortem events, may act together on donor lungs and eventually culminate in primary graft dysfunction (PGD) after transplantation as well as other poor short-term outcomes.

AREAS COVERED

This review focuses on the predisposing factors contributing to injuries to the donor lungs, specifically focusing on the pathogenesis of these injuries and their impact on post-transplant outcomes. Additionally, various maneuvers to mitigate donor lung injuries have been proposed.

EXPERT OPINION

The selection criteria for eligible donors vary and may be poor discriminators of lung injury. Not all transplanted lungs are in ideal condition. With the rapidly increasing waiting list for LTx, the trend of using marginal donors has become more apparent, underscoring the need to gain a deeper understanding of donor lung injuries and discover more donor resources.

Utilization and outcomes of deceased donor SARS-CoV-2-positive organs for solid organ transplantation in the United States

Coronavirus disease-19 has had a marked impact on the transplant population and processes of care for transplant centers and organ allocation. Several single-center studies have reported successful utilization of deceased donors with positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) tests. Our aims were to characterize testing, organ utilization, and transplant outcomes with donor SARS-CoV-2 status in the United States. We used Scientific Registry of Transplant Recipients data from March 12, 2020 to August 31, 2021 including a custom file with SARS-CoV-2 testing data. There were 35 347 donor specimen SARS-CoV-2 tests, 77.5% upper respiratory samples, 94.6% polymerase chain reaction tests, and 1.2% SARS-CoV-2-positive tests. Donor age, gender, history of hypertension, and diabetes were similar by SARS-CoV-2 status, while positive SARS-CoV-2 donors were more likely African-American, Hispanic, and donors after cardiac death (p-values <.01). Recipient demographic characteristics were similar by donor SARS CoV-2 status. Adjusted donor kidney discard (odds ratio = 2.08, 95% confidence interval [CI] 1.66-2.61) was higher for SARS-CoV-2-positive donors while donor liver (odds ratio = 0.44, 95% CI 0.33-0.60) and heart recovery (odds ratio = 0.44, 95% CI 0.31-0.63) were significantly reduced. Overall post-transplant graft survival for kidney, liver, and heart recipients was comparable by donor SARS-CoV-2 status. Cumulatively, there has been significantly lower utilization of SARS-CoV-2 donors with no evidence of reduced recipient graft survival with variations in practice over time.

Organ transplantation using COVID-19-positive deceased donors

The COVID-19 pandemic has influenced organ transplantation decision making. Opinions regarding the utilization of coronavirus disease-2019 (COVID-19) donors are mixed. We hypothesize that COVID-19 infection of deceased solid organ transplant donors does not affect recipient survival. All deceased solid organ transplant donors with COVID-19 testing results from March 15, 2020 to September 30, 2021 were identified in the OPTN database. Donors were matched to recipients and stratified by the COVID-19 test result. Outcomes were assessed between groups. COVID-19 test results were available for 17 694 donors; 150 were positive. A total of 269 organs were transplanted from these donors, including 187 kidneys, 57 livers, 18 hearts, 5 kidney-pancreases, and 2 lungs. The median time from COVID-19 testing to organ recovery was 4 days for positive and 3 days for negative donors. Of these, there were 8 graft failures (3.0%) and 5 deaths (1.9%). Survival of patients receiving grafts from COVID-19-positive donors is equivalent to those receiving grafts from COVID-19-negative donors (30-day patient survival = 99.2% COVID-19 positive; 98.6% COVID-19 negative). Solid organ transplantation using deceased donors with positive COVID-19 results does not negatively affect early patient survival, though little information regarding donor COVID-19 organ involvement is known. While transplantation is feasible, more information regarding COVID-19-positive donor selection is needed.

Risk of Severe Acute Respiratory Syndrome Coronavirus 2 Transmission Through Solid Organ Transplantation and Outcomes of Coronavirus Disease 2019 Among Recent Transplant Recipients

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmissible through lung transplantation, and outcomes among infected organ recipients may be severe. Transmission risk to extrapulmonary organ recipients and recent (within 30 days of transplantation) SARS-CoV-2-infected recipient outcomes are unclear.

METHODS

During March 2020-March 2021, potential SARS-CoV-2 transmissions through solid organ transplantation were investigated. Assessments included SARS-CoV-2 testing, medical record review, determination of likely transmission route, and recent recipient outcomes.

RESULTS

During March 2020-March 2021, approximately 42 740 organs were transplanted in the United States. Forty donors, who donated 140 organs to 125 recipients, were investigated. Nine (23%) donors and 25 (20%) recipients were SARS-CoV-2 positive by nucleic acid amplification test (NAAT). Most (22/25 [88%]) SARS-CoV-2-infected recipients had healthcare or community exposures. Nine SARS-CoV-2-infected donors donated 21 organs to 19 recipients. Of these, 3 lung recipients acquired SARS-CoV-2 infections from donors with negative SARS-CoV-2 testing of pretransplant upper respiratory tract specimens but from whom posttransplant lower respiratory tract (LRT) specimens were SARS-CoV-2 positive. Sixteen recipients of extrapulmonary organs from SARS-CoV-2-infected donors had no evidence of posttransplant COVID-19. All-cause mortality within 45 days after transplantation was 6-fold higher among SARS-CoV-2-infected recipients (9/25 [36%]) than those without (6/100 [6%]).

CONCLUSIONS

Transplant-transmission of SARS-CoV-2 is uncommon. Pretransplant NAAT of lung donor LRT specimens may prevent transmission of SARS-CoV-2 through transplantation. Extrapulmonary organs from SARS-CoV-2-infected donors may be safely usable, although further study is needed. Reducing recent recipient exposures to SARS-CoV-2 should remain a focus of prevention.

Utilization of SARS-COV-2 positive donors and recipients for liver transplantation in the pandemic era - An evidence-based review

The current SARS-COV-2 pandemic led to a drastic drop in liver donation and transplantation in DDLT and LDLT settings. Living donations have decreased more than deceased organ donation due to the need to protect the interest of donors. In the SARS-COV-2 pandemic, major professional societies worldwide recommended against the use of organs from donors with acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. The basis for these recommendations are; SARS-CoV-2 could be transmitted to the recipient through organ transplantation and can result in severe manifestations; only limited effective targeted therapies are available, risk of transmission to the healthcare professionals, logistical limitations, and ethical concerns. In addition, end-stage liver disease patients on the waiting list represent vulnerable populations and are at higher risk for severe COVID-19 infection. Therefore, deferring life-saving transplants from COVID-positive donors during a pandemic may lead to more collateral damage by causing disease progression, increased death, and dropout from the waitlist. As this SARS-COV-2 pandemic is likely to stay with us for some time, we have to learn to co-exist with it. We believe that utilizing organs from mild/ asymptomatic COVID19 positive donors may expand the organ donor pool and mitigate disruptions in transplantation services during this pandemic.

How COVID-19 Affects Lung Transplantation: A Comprehensive Review

Lung transplant (LuTx) recipients are at a higher risk of developing serious illnesses from COVID-19, and thus, we have closely reviewed the consequences of the COVID-19 pandemic on lung transplantation. In most transplant centers, the overall LuTx activity significantly declined and led to a specific period of restricting lung transplantation to urgent cases. Moreover, several transplant centers reported difficulties due to the shortage of ICU capacities. The fear of donor-derived transmission generated extensive screening programs. Nevertheless, reasonable concerns about the unnecessary losses of viable organs were also raised. The overall donor shortage resulted in increased waiting-list mortality, and COVID-19-associated ARDS became an indication of lung transplantation. The impact of specific immunosuppressive agents on the severity of COVID-19 varied. Corticosteroid discontinuation was not found to be beneficial for LuTx patients. Tacrolimus concentrations were reported to increase during the SARS-CoV-2 infection, and in combination with remdesivir, tacrolimus may clinically impact renal functions. Monoclonal antibodies were shown to reduce the risk of hospitalization in SOT recipients. However, understanding the pharmacological interactions between the anti-COVID-19 drugs and the immunosuppressive drugs requires further research.

Optimization of initial dose regimen of tacrolimus in paediatric lung transplant recipients based on Monte Carlo simulation

WHAT IS KNOWN AND OBJECTIVES

The initial tacrolimus dose regimen in paediatric lung transplant recipients is unknown. The present study optimized the initial tacrolimus dose regimen for paediatric lung transplant recipients.

METHODS

This study was based on a published population pharmacokinetic model of tacrolimus in lung transplant recipients and used Monte Carlo simulations to recommend an initial dose regimen of tacrolimus in paediatric lung transplant recipients.

RESULTS

Without voriconazole, the tacrolimus doses recommended for paediatric lung transplant recipients who were not CYP3A5*1 carriers were 0.02, 0.03, and 0.04 mg/kg/day, split into two doses, for weights of 10-16, 16-30, and 30-40 kg, respectively. For paediatric lung transplant recipients who were CYP3A5*1 carriers, the tacrolimus doses of 0.03, 0.04, 0.05, and 0.06 mg/kg/day, split into two doses, were recommended for weights of 10-16, 16-25, 25-30, and 30-40 kg, respectively. With voriconazole, the tacrolimus dose recommended for paediatric lung transplant recipients who were not CYP3A5*1 carriers was 0.02 mg/kg/day, split into two doses, for weights of 10-40 kg. For paediatric lung transplant recipients who were CYP3A5*1 carriers, tacrolimus doses of 0.02 and 0.03 mg/kg/day, split and two doses, were recommended for weights of 10-24 and 24-40 kg, respectively.

WHAT IS NEW AND CONCLUSIONS

This study developed tacrolimus dose regimens for the first time for paediatric lung transplant recipients using Monte Carlo simulation and optimized initial dosage in paediatric lung transplant recipients.

Solid organ transplantation from donors with recent or current SARS-CoV-2 infection: A Systematic Review

BACKGROUND

Solid-organ transplantation (SOT) from SARS-CoV-2 positive donors could be a life-saving opportunity worth grasping. We perform a systematic review of SOT using SARS-CoV-2 positive donors.

METHODS

The search was performed in PubMed, Cochrane COVID-19 Study Register, and Web of Science databases, including studies conducted till the 31^th of December 2021 from SOT adult recipients from a donor with past or current SARS-CoV-2 infection. Outcomes were viral transmission, COVID-19 symptoms, mortality, hospital stay, and complications. PROSPERO Register Number: CRD42022303242 FINDINGS: Sixty-nine recipients received 48 kidneys, 18 livers and 3 hearts from 57 donors. Six additional transplants from positive lungs were identified. IgG + anti-SARS-CoV-2 titers were detected among 10/16 recipients; only 4% (3/69) recipients were vaccinated. Non-lung transplant recipients received organs from 10/57 (17.5%) donors with persistent COVID-19 and SARS-CoV-2 RNA was detected (median 32 Cycle threshold [Ct]) in 18/57, at procurement. Among non-lung transplant recipients, SARS-CoV-2 viral transmission was not documented. Four patients presented delayed graft dysfunction, two patients acute rejection, and two patients died of septic shock. The median (IQR) hospital stay was 18 (11-28) days in recipients from symptomatic donors. Viral transmission occurred from three lung donors to their recipients, who developed COVID-19 symptoms. One of the recipients subsequently died.

CONCLUSION

Use of non-lung (kidney, liver and heart) organs from SARS-CoV-2 positive donors seem to be a safe practice, with a low risk of transmission irrespective of the presence of symptoms at the time of procurement. Low viral replication (Ct > 30) was safe among non-lung donors, even if persistently symptomatic at procurement.

A systematic review of Vaccine Breakthrough Infections by SARS-CoV-2 Delta Variant

Vaccines are proving to be highly effective in controlling hospitalization and deaths associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, as shown by clinical trials and real-world evidence. However, a deadly second wave of coronavirus disease 2019 (COVID-19), infected by SARS-CoV-2 variants, especially the Delta (B.1.617.2) variant, with an increased number of post-vaccination breakthrough infections were reported in the world recently. Actually, Delta variant not only resulted in a severe surge of vaccine breakthrough infections which was accompanied with high viral load and transmissibility, but also challenged the development of effective vaccines. Therefore, the biological characteristics and epidemiological profile of Delta variant, the current status of Delta variant vaccine breakthrough infections and the mechanism of vaccine breakthrough infections were discussed in this article. In addition, the significant role of the Delta variant spike (S) protein in the mechanism of immune escape of SARS-CoV-2 was highlighted in this article. In particular, we further discussed key points on the future SARS-CoV-2 vaccine research and development, hoping to make a contribution to the early, accurate and rapid control of the COVID-19 epidemic.

Current trends in candidate selection, contraindications, and indications for lung transplantation

Lung transplantation is an established treatment option that can improve quality of life and prolong survival for select patients diagnosed with end-stage lung disease. Given the gaps in organ donation and failures to make effective use of available organs, careful selection of candidates for lung transplant remains one of the most important considerations of the transplant community. Toward this end, we briefly reviewed recent trends in pretransplant evaluation, candidate selection, organ allocation, and organ preservation techniques. Since the latest consensus statement regarding appropriate selection of lung transplant candidates, many advances in the science and practice of lung transplantation have emerged and influenced our perspective of ‘contraindications’ to transplant. These advances have made it increasingly possible to pursue lung transplant in patients with risk factors for decreased survival—namely, older recipient age, increased body mass index, previous chest surgery, poorer nutritional status, and presence of chronic infection, cardiovascular disease, or extrapulmonary comorbid conditions. Therefore, we reviewed the updated evidence demonstrating the prognostic impact of these risk factors in lung transplant recipients. Lastly, we reviewed the salient evidence for current trends in disease-specific indications for lung transplantation, such as chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, cystic fibrosis, emphysema due to alpha-1 antitrypsin deficiency, and pulmonary arterial hypertension, among other less common end-stage diseases. Overall, lung transplant remains an exciting field with considerable hope for patients as they experience remarkable improvements in quality of life and survival in the modern era.

Increasing incidence of lung transplantation in patients with post-COVID-19 pulmonary fibrosis

Twenty months into the COVID-19 pandemic, we are still learning about the various long-term consequences of COVID-19 infection. While many patients do recover with minimal long-term consequences, some patients develop irreversible parenchymal and interstitial lung damage leading to diffuse pulmonary fibrosis. Unfortunately, these are some of the consequences of post-SARS-CoV-2 infection which thousands more people around the world will experience and which will outlast the pandemic for a long time to come. It is now being observed at various leading medical centres around the world that lung transplantation may be the only meaningful treatment available to a select group of patients experiencing serious lung damage and non-resolving COVID-19-associated respiratory failure, resulting from the triad of coronavirus infection, a hyper-inflammatory immune response to it and the inability of the human body to repair that injury.

Brazilian initial experience with lung transplantation due to irreversible lung fibrosis post-COVID-19 in a national reference center: a cohort study

BACKGROUND

Lung transplantation (LTx) has been discussed as an option for treating irreversible lung fibrosis post-coronavirus disease 2019 (COVID-19), in selected cases.

OBJECTIVES

To report on the initial experience and management of end-stage lung disease due to COVID-19 at a national center reference in Brazil.

DESIGN AND SETTING

Cohort study conducted at a national reference center for lung transplantation.

METHODS

Medical charts were reviewed regarding patients' demographics and pre-COVID-19 characteristics, post-LTx due to COVID-19.

RESULTS

Between March 2020 and September 2021, there were 33 cases of LTx. During this period, we evaluated 11 cases of severe COVID-19-related acute respiratory distress syndrome (ARDS) that were potentially candidates for LTx. Among these, LTx was only indicated for three patients (9.1%). All of these patients were on venovenous extracorporeal membrane oxygenation (ECMO), and the procedure that they underwent was central venoarterial ECMO. All three patients were still alive after the first 30 postoperative days. However, patient #1 and patient #2 subsequently died due to fungal sepsis on the 47th and 52nd postoperative days, respectively. Patient #3 was discharged on the 30th postoperative day.

CONCLUSIONS

LTx is feasible among these complex patients. Survival over the first 30 days was 100%, and this favors surgical feasibility. Nonetheless, these were critically ill patients.

Lung donation following SARS-CoV-2 infection

There have been over 177 million cases of COVID-19 worldwide, many of whom could be organ donors. Concomitantly, there is an anticipated increase in the need for donor lungs due to expanding indications. Given that the respiratory tract is most commonly affected by COVID-19, there is an urgent need to develop donor assessment criteria while demonstrating safety and "efficacy" of lung donation following COVID-19 infection. Accordingly, we report an intentional transplant using lungs from a donor with recent, microbiologically confirmed, COVID-19 infection into a recipient suffering from COVID-19 induced ARDS and pulmonary fibrosis. In addition to the standard clinical assays, both donor and recipient lungs were analyzed using RNAscope, which confirmed that tissues were negative for SARS-CoV-2. Immunohistochemistry demonstrated colocalized KRT17+ basaloid-like epithelium and COL1A1+ fibroblasts, a marker suggestive of lung fibrosis in COVID-19 associated lung disease, in the explanted recipient lungs but absent in the donor lungs. We demonstrate that following a thorough assessment, lung donation following resolved COVID-19 infection is safe and feasible.

Liver transplantation from active COVID-19 donors: A lifesaving opportunity worth grasping?

COVID-19 pandemic dramatically impacted transplantation landscape. Scientific societies recommend against the use of donors with active SARS-CoV-2 infection. Italian Transplant Authority recommended to test recipients/donors for SARS-CoV-2-RNA immediately before liver transplant (LT) and, starting from November 2020, grafts from deceased donors with active SARS-CoV-2 infection were allowed to be considered for urgent-need transplant candidates with active/resolved COVID-19. We present the results of the first 10 LTs with active COVID-19 donors within an Italian multicenter series. Only two recipients had a positive molecular test at LT and one of them remained positive up to 21 days post-LT. None of the other eight recipients was found to be SARS-CoV-2 positive during follow-up. IgG against SARS-CoV-2 at LT were positive in 80% (8/10) of recipients, and 71% (5/7) showed neutralizing antibodies, expression of protective immunity related to recent COVID-19. In addition, testing for SARS-CoV-2 RNA on donors' liver biopsy at transplantation was negative in 100% (9/9), suggesting a very low risk of transmission with LT. Immunosuppression regimen remained unchanged, according to standard protocol. Despite the small number of cases, these data suggest that transplanting livers from donors with active COVID-19 in informed candidates with SARS-CoV-2 immunity, might contribute to safely increase the donor pool.

Visualizing in deceased COVID-19 patients how SARS-CoV-2 attacks the respiratory and olfactory mucosae but spares the olfactory bulb

Anosmia, the loss of smell, is a common and often the sole symptom of COVID-19. The onset of the sequence of pathobiological events leading to olfactory dysfunction remains obscure. Here, we have developed a postmortem bedside surgical procedure to harvest endoscopically samples of respiratory and olfactory mucosae and whole olfactory bulbs. Our cohort of 85 cases included COVID-19 patients who died a few days after infection with SARS-CoV-2, enabling us to catch the virus while it was still replicating. We found that sustentacular cells are the major target cell type in the olfactory mucosa. We failed to find evidence for infection of olfactory sensory neurons, and the parenchyma of the olfactory bulb is spared as well. Thus, SARS-CoV-2 does not appear to be a neurotropic virus. We postulate that transient insufficient support from sustentacular cells triggers transient olfactory dysfunction in COVID-19. Olfactory sensory neurons would become affected without getting infected.

Use of Organs from SARS-CoV-2 Infected Donors: Is It Safe? A Contemporary Review

PURPOSE OF REVIEW

As the prevalence of individuals with recovered coronavirus disease 2019 (COVID-19) increases, determining if and when organs from these donors can be safely used is an important priority. We examined current knowledge of outcomes of transplant using donors with recovered COVID-19.

RECENT FINDINGS

A literature search of PubMed and Google scholar databases was conducted to identify articles with terms "SARS-CoV2," "COVID-19," "donor recovered," and "transplantation" published through 08/10/2021. We identified 25 reports detailing 94 recipients of both abdominal and thoracic transplants from donors with both prior and active COVID-19 infection. Rates of transmission to the recipient and of transplanted organ dysfunction were low among reports of donors with prior COVID-19 infection. End organ dysfunction and transmission were more common with active infection, although few reports are available. Standardized reporting is needed to better assess the impact of donor symptomatology, cycle thresholds, and individual recipient risk factors on postoperative outcomes.

SUMMARY

Available reports suggest that transplantation from COVID-19 donors may be feasible and safe, at least in short term follow-up. Nevertheless, there is a need for standardized testing and management protocols which should be tailored for available resources. While increased availability of COVID-19 vaccinations will mitigate risks of donor-derived COVID-19 and simplify management, continued vigilance is warranted during the ongoing public health emergency.

Clinical Practice Guideline for Solid Organ Donation and Transplantation During the COVID-19 Pandemic

The coronavirus 2019 (COVID-19) pandemic has disrupted health systems worldwide, including solid organ donation and transplantation programs. Guidance on how best to screen patients who are potential organ donors to minimize the risks of COVID-19 as well as how best to manage immunosuppression and reduce the risk of COVID-19 and manage infection in solid organ transplant recipients (SOTr) is needed.

METHODS

Iterative literature searches were conducted, the last being January 2021, by a team of 3 information specialists. Stakeholders representing key groups undertook the systematic reviews and generation of recommendations using a rapid response approach that respected the Appraisal of Guidelines for Research and Evaluation II and Grading of Recommendations, Assessment, Development and Evaluations frameworks.

RESULTS

The systematic reviews addressed multiple questions of interest. In this guidance document, we make 4 strong recommendations, 7 weak recommendations, 3 good practice statements, and 3 statements of "no recommendation."

CONCLUSIONS

SOTr and patients on the waitlist are populations of interest in the COVID-19 pandemic. Currently, there is a paucity of high-quality evidence to guide decisions around deceased donation assessments and the management of SOTr and waitlist patients. Inclusion of these populations in clinical trials of therapeutic interventions, including vaccine candidates, is essential to guide best practices.

Challenges in organizing a Belgian reference hospital to respond to the COVID-19 pandemic: A case report

The coronavirus disease 2019 (COVID‐19) pandemic resulted in an enormous influx of seriously ill patients in the hospitals worldwide. After its initial impact in Asia, Europe also suffered greatly. Caring for COVID‐19 patients whist maintaining treatment for patients with other conditions was a complex planning and management challenge. A series of interventions has been implemented to increase hospital capacity in response to the pandemic. Hospital provision interventions included the purchase of equipment, the establishment of additional hospital facilities and the redeployment of staff and other resources. Ensuring safe and high quality care to both COVID‐19 patients and those with other conditions was a crucial aspect of the Belgian response in this current health crisis.

Involvement of 4-hydroxy-2-nonenal in the pathogenesis of pulmonary fibrosis

Pulmonary fibrosis is a chronic progressive disease with high incidence, prevalence, and mortality rates worldwide. It is characterized by excessive accumulation of extracellular matrix in the lung parenchyma. The cellular and molecular mechanisms involved in its pathogenesis are complex, and some are still unknown. Several studies indicate that oxidative stress, characterized by overproduction of 4-hydroxy-2-nonenal (4-HNE), is an important player in pulmonary fibrosis. 4-HNE is a highly reactive compound derived from polyunsaturated fatty acids that can react with proteins, phospholipids, and nucleic acids. Thus, many of the altered cellular mechanisms that contribute to this disease can be explained by the participation of 4-HNE. Here, we summarize the current knowledge on the molecular states and signal transduction pathways that contribute to the pathogenesis of pulmonary fibrosis. Furthermore, we describe the participation of 4-HNE in various mechanisms involved in pulmonary fibrosis development, with a focus on the cell populations involved in the initiation, development, and maintenance of the fibrotic process, mainly alveolar cells, endothelial cells, macrophages, and inflammatory cells. Due to its characteristic activity as a second messenger, 4-HNE, in addition to being a consequence of oxidative stress, can support maintenance of the inflammatory and fibrotic process by spreading the effects of reactive oxygen species (ROS). Thus, regulation of 4-HNE levels could be a viable strategy to reduce its effects on the mechanisms involved in pulmonary fibrosis development.

Successful lung transplantation from a donor who had recovered from SARS-CoV-2 pneumonia

During the present COVID-19 pandemic, transplantation of donor lungs with a history of COVID-19 infection is a critical issue. Donor-derived virus infection and graft dysfunction are possible after transplantation. However, use of such lungs could save the lives of patients requiring emergency transplantation. We successfully transplanted lungs from a brain-dead donor who had recovered from SARS-CoV-2 into a severe respiratory failure patient supported with ECMO who needed an emergency transplant. At the 3-month follow-up, our patient showed no evidence of COVID-19 transmission or graft dysfunction.

Evidence of SARS-CoV-2 Infection in Cells, Tissues, and Organs and the Risk of Transmission Through Transplantation

The emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus responsible for the coronavirus disease 2019 (COVID-19) pandemic has raised concerns for programs overseeing donation and transplantation of cells, tissues, and organs (CTO) that this virus might be transmissible by transfusion or transplantation. Transplant recipients are considered particularly vulnerable to pathogens because of immunosuppression, and SARS-CoV-2 is likely to generate complications if contracted. Several signs and symptoms observed in COVID-19 positive patients reflect damage to multiple organs and tissues, raising the possibility of extrapulmonary SARS-CoV-2 infections and risk of transmission. At the beginning of the pandemic, a consensus has emerged not to consider COVID-19 positive patients as potential living or deceased donors, resulting in a global decrease in transplantation procedures. Medical decision-making at the time of organ allocation must consider safely alongside the survival advantages offered by transplantation. To address the risk of transmission by transplantation, this review summarizes the published cases of transplantation of cells or organs from donors infected with SARS-CoV-2 until January 2021 and assesses the current state of knowledge for the detection of this virus in different biologic specimens, cells, tissues, and organs. Evidence collected to date raises the possibility of SARS-CoV-2 infection and replication in some CTO, which makes it impossible to exclude transmission through transplantation. However, most studies focused on evaluating transmission under laboratory conditions with inconsistent findings, rendering the comparison of results difficult. Improved standardization of donors and CTO screening practices, along with a systematic follow-up of transplant recipients could facilitate the assessment of SARS-CoV-2 transmission risk by transplantation.

The Year 2020 in Review: Noteworthy Literature for Thoracic Transplant Anesthesiologists

The year 2020 was a monumental year in medicine, and this review focuses on selected articles for cardiothoracic anesthesiologists and perioperative physicians involved in the care of heart and lung transplant patients. In the field of lung transplantation, significant strides were made in our knowledge of risk stratification during the preoperative assessment of potential recipients, perioperative transfusion medicine, and the administration of coagulation factor concentrates. In addition, variations in perioperative management and outcomes between institutions were studied across an assortment of metrics regarding lung transplantation, including case volumes and anesthetic practices. Transitioning to topics in the field of heart transplantation, consideration was given to recipients with adult congenital heart disease, and separately, approaches to expanding the donor pool through donation after circulatory death. With regard to preoperative support, outcomes for the total artificial heart as well as the MitraClip as bridges to transplantation were published.

Editorial: COVID-19 immunology and organ transplantation

PURPOSE OF REVIEW

The aim of this study was to provide a critical appraisal of the literature on the effects of the COVID-19 pandemic on organ transplantation, with a specific focus on lung transplantation given the predominant pulmonary involvement of the virus.

RECENT FINDINGS

There was a significant decrease in lung transplant volumes during the first wave of the COVID-19 pandemic due to a combination of reduced availability of donors and an imbalance between waitlist additions and inactivations. SARS-CoV-2 infection was subsequently associated with an exuberant immune response that can lead to the development of postinfectious fibrotic lung disease. Few lung transplants have been performed in previously infected recipients and long-term outcomes remain unknown. Although the lung transplant volume rebounded during the second wave, it is unclear what the long-term effects of healthcare resource limitation and public health measures will have on transplant volumes in the future. Outcomes after SARS-CoV-2 infection in previous lung transplant recipients appear to be worse than the general public, and, although an immunosuppressed state likely contributes to these outcomes, whether immunosuppression should be altered in those exposed to or infected with SARS-CoV-2 remains unanswered in the absence of unequivocal data.

SUMMARY

The COVID-19 pandemic has presented a number of challenges for lung transplant programs across the globe. Multiple research questions remain to be answered in order to optimally manage lung transplant recipients in the context of this pandemic.

The impact of the SARS-CoV-2 pandemic and COVID-19 on lung transplantation in the UK: Lessons learned from the first wave

Background

Lung transplantation is particularly susceptible to the impact of the severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) pandemic, and evaluation of changes to practice is required to inform future decision‐making.

Methods

A retrospective review of the UK Transplant Registry (UKTR) and national survey of UK lung transplant centers has been performed.

Results

There was geographic variation in the prevalence of COVID‐19 infection across the UK. The number of donors fell by 48% during the early pandemic period. Lung utilization fell to 10% (compared with 24% for the same period of 2019). The number of lung transplants performed fell by 77% from 53, March to May 2019, to 12. Seven (58%) of these were performed in a single‐center, designated “COVID‐light.” The number of patients who died on the lung transplant waiting list increased, compared to the same period of 2019 (p = .0118). Twenty‐six lung transplant recipients with confirmed COVID‐19 infection were reported during the study period.

Conclusion

As the pandemic continues, reviewing practice and implementing the lessons learned during this period, including the use of robust donor testing strategies and the provision of “COVID‐light” hospitals, are vital in ensuring the safe continuation of our lung transplant program.