First experience of SARS-CoV-2 infections in solid organ transplant recipients in the Swiss Transplant Cohort Study

Infections in lung transplanted patients: A review

Lung transplantation can improve the survival of patients with severe chronic pulmonary disorders. However, the short- and long-term risk of infections can increase morbidity and mortality rates. A non-systematic review was performed to provide the most updated information on pathogen, host, and environment-related factors associated with the occurrence of bacterial, fungal, and viral infections as well as the most appropriate therapeutic options. Bacterial infections account for about 50% of all infectious diseases in lung transplanted patients, while viruses represent the second cause of infection accounting for one third of all infections. Almost 10% of patients develop invasive fungal infections during the first year after lung transplant. Pre-transplantation comorbidities, disruption of physical barriers during the surgery, and exposure to nosocomial pathogens during the hospital stay are directly associated with the occurrence of life-threatening infections. Empiric antimicrobial treatment after the assessment of individual risk factors, local epidemiology of drug-resistant pathogens and possible drug-drug interactions can improve the clinical outcomes.

Designing and analyzing studies of coronavirus disease 2019 and post-acute sequelae of severe acute respiratory syndrome coronavirus 2 among immunocompromised individuals

Observational studies of coronavirus disease 2019 (COVID-19) among transplant candidates and recipients remain important as immunocompromised patients formed a very small proportion of patients included in COVID-19 trials and large database analyses. We discuss methods that have been used in such analyses to evaluate the impact of vaccination on the risk of symptomatic COVID-19 in such patients and on the probability of developing post-acute sequelae of severe acute respiratory syndrome coronavirus 2 after the onset of infection. We also propose future directions for research and discuss the methods that will be useful to conduct such investigations. The study design and analytical issues that we consider have the potential to be helpful not only for COVID-19 research but also for other infections as well.

COVID-19 Outcomes and Vaccinations in Swedish Solid Organ Transplant Recipients 2020-2021: A Nationwide Multi-Register Comparative Cohort Study

Increased COVID-19-related morbidity and mortality have been reported in solid organ transplant recipients (SOTRs). Most studies are underpowered for rigorous matching. We report infections, hospitalization, ICU care, mortality from COVID-19, and pertinent vaccination data in Swedish SOTRs 2020-2021. We conducted a nationwide cohort study, encompassing all Swedish residents. SOTRs were identified with ICD-10 codes and immunosuppressant prescriptions. Comparison cohorts were weighted based on a propensity score built from potential confounders (age, sex, comorbidities, socioeconomic factors, and geography), which achieved a good balance between SOTRs and non-SOTR groups. We included 10,372,033 individuals, including 9073 SOTRs. Of the SARS-CoV-2 infected, 47.3% of SOTRs and 19% of weighted comparator individuals were hospitalized. ICU care was given to 8% of infected SOTRs and 2% of weighted comparators. The case fatality rate was 7.7% in SOTRs, 6.2% in the weighted comparison cohort, and 1.3% in the unweighted comparison cohort. SOTRs had an increased risk of contracting COVID-19 (HR = 1.15 p < 0.001), being hospitalized (HR = 2.89 p < 0.001), receiving ICU care (HR = 4.59 p < 0.001), and dying (HR = 1.42 p < 0.001). SOTRs had much higher morbidity and mortality than the general population during 2020-2021. Also compared with weighted comparators, SOTRs had an increased risk of contracting COVID-19, being hospitalized, receiving ICU care, and dying. In Sweden, SOTRs were vaccinated earlier than weighted comparators. Lung transplant recipients had the worst outcomes. Excess mortality among SOTRs was concentrated in the second half of 2021.

Humoral and cellular immune responses after COVID-19 vaccination of lung transplant recipients and patients on the waiting list: a 6-month follow-up

Background

Data on cellular response and the decay of antibodies and T cells in time are scarce in lung transplant recipients (LTRs). Additionally, the development and durability of humoral and cellular immune responses have not been investigated in patients on the waitlist for lung transplantation (WLs). Here, we report our 6-month follow-up of humoral and cellular immune responses of LTRs and WLs, compared with controls.

Methods

Humoral responses to two doses of the mRNA-1273 vaccination were assessed by determining spike (S)-specific IgG antibodies and neutralizing antibodies. Cellular responses were investigated by interferon gamma (IFN-γ) release assay (IGRA) and IFN-γ ELISpot assay at 28 days and 6 months after the second vaccination.

Results

In LTRs, the level of antibodies and T-cell responses was significantly lower at 28 days after the second vaccination. Also, WLs had lower antibody titers and lower T-cell responses compared with controls. Six months after the second vaccination, all groups showed a decrease in antibody titers and T-cell responses. In WLs, the rate of decline of neutralizing antibodies and T-cell responses was significantly higher than in controls.

Conclusion

Our results show that humoral and cellular responses in LTRs, if they develop, decrease at rates comparable with controls. In contrast, the inferior cellular responses and the rapid decay of both humoral and cellular responses in the WL groups imply that WLs may not be protected adequately by two vaccinations and repeat boostering may be necessary to induce protection that lasts beyond the months immediately post-transplantation.

Coronavirus disease 2019 in kidney transplant recipients: a systematic review and meta-analysis

Introduction

The clinical presentation and outcomes of coronavirus disease 2019 (COVID-19) in kidney transplant recipients (KTRs) have not been well studied.

Methods

We performed a meta-analysis to examine the presenting features, outcomes and the effect of treatment on outcomes of KTRs with COVID-19. Database search was performed up to 5 September 2020 through PubMed, Embase, Web of Science, Scopus and CENTRAL.

Results

Overall, 23 studies (1,373 patients) were included in the review and meta-analysis. The most common presenting symptoms included fever (74.0%, 95% confidence interval [CI] 65.3-81.1), cough (63.3%, 95% CI 56.5-69.6) and dyspnoea (47.5%, 95% CI 39.6-55.6). Pooled rates of mortality and critical illness were 21.1% (95% CI 15.3-28.4) and 27.7% (95% CI 21.5-34.8), respectively. Acute kidney injury occurred in 38.9% (95% CI 30.6-48.1) and dialysis was required in 12.4% (95% CI 8.3-18.0) of the cases.

Conclusion

Kidney transplant recipients with COVID-19 have a similar clinical presentation as the general population, but they have higher morbidity and mortality. It is uncertain whether high-dose corticosteroid or hydroxychloroquine reduces the risks of mortality in KTRs with COVID-19.

A Review of the Role of Artificial Intelligence in Healthcare

Artificial intelligence (AI) applications have transformed healthcare. This study is based on a general literature review uncovering the role of AI in healthcare and focuses on the following key aspects: (i) medical imaging and diagnostics, (ii) virtual patient care, (iii) medical research and drug discovery, (iv) patient engagement and compliance, (v) rehabilitation, and (vi) other administrative applications. The impact of AI is observed in detecting clinical conditions in medical imaging and diagnostic services, controlling the outbreak of coronavirus disease 2019 (COVID-19) with early diagnosis, providing virtual patient care using AI-powered tools, managing electronic health records, augmenting patient engagement and compliance with the treatment plan, reducing the administrative workload of healthcare professionals (HCPs), discovering new drugs and vaccines, spotting medical prescription errors, extensive data storage and analysis, and technology-assisted rehabilitation. Nevertheless, this science pitch meets several technical, ethical, and social challenges, including privacy, safety, the right to decide and try, costs, information and consent, access, and efficacy, while integrating AI into healthcare. The governance of AI applications is crucial for patient safety and accountability and for raising HCPs' belief in enhancing acceptance and boosting significant health consequences. Effective governance is a prerequisite to precisely address regulatory, ethical, and trust issues while advancing the acceptance and implementation of AI. Since COVID-19 hit the global health system, the concept of AI has created a revolution in healthcare, and such an uprising could be another step forward to meet future healthcare needs.

Retrospective Evaluation of COVID-19 Infection and COVID-19 Vaccines in Heart Transplant Patients

BACKGROUND

Patients who have performed solid organ transplantation in terms of COVID-19 infection are included in the high-risk group. In this study, it was aimed to evaluate the relationship between vaccination and retrospective evaluation of 32 patients who underwent a heart transplant in the clinic and tested positive for SARS-CoV-2 polymerase chain reaction.

METHODS

In this study, demographic characteristics of the cases, comorbidities, timing of heart transplantation, immunosuppressive treatments, symptoms of COVID-19 infection, lung imaging findings, follow-up (outpatient/inpatient), treatments, 1-month mortality, and vaccination histories against COVID-19 infection were evaluated. The data obtained from the study were analyzed with SPSS version 25.0.

RESULTS

The 3 most common symptoms are cough (37.5%), myalgia (28.1%), and fever (21.8%). COVID-19 infection was severe in 6.2% of the patients, moderate in 37.5%, and mild in 56.2%. Hospitalization was required in 5 patients (15.6%, 1 in the intensive care unit), and the other patients were followed up as an outpatient. Severe COVID-19 infection was seen more in 33% of unvaccinated patients; 93.5% were vaccinated. Nineteen patients (68%) were vaccinated before COVID-19 infection. Our patients received the CoronoVac (Sinovac, China) vaccine.

CONCLUSION

COVID-19 infection is more likely to be severe and mortal in patients with heart transplant recipients. It is also crucial to comply with preventive measures other than immunization in this group of patients. This study is the largest series investigating COVID-19 infection in heart transplant recipient patients in our country.

Disease Course, Management and Outcomes in Kidney Transplant Recipients with SARS-CoV-2 Infection during the Omicron-Variant Wave: A Single-Center Experience

Background: Since December 2019, kidney transplant recipients (KTRs) have experienced a great impact of the coronavirus disease 2019 (COVID-19) pandemic, with a higher risk of morbidity and mortality compared to the general population. Preliminary data in KTRs suggest that the Omicron variant, which has been dominant since December 2021, is more infectious than the previous ones but is associated with reduced risk of severity and low lethality rates. The purpose of our study was to assess the disease course and outcomes of the SARS-CoV-2 infection in KTRs during the Omicron-surge. Methods: This retrospective study included 451 KTRs diagnosed with SARS-CoV-2 infection between 1 December 2021 and 30 September 2022. Demographic and clinical characteristics at the time of infection, vaccination data, treatment, clinical course, and outcomes were recorded and analyzed. Results: Mean age was 51.8 ± 13.7 years with a male predominance (61.2%). The majority (76.1%) were vaccinated with at least three doses of the available mRNA vaccines, although serology revealed low anti-SARS-CoV-2 antibody titers before infection (33 [3.3–1205] AU/mL). Only 6% of the patients experienced moderate–severe disease. Accordingly, there was low prevalence of adverse outcomes, such as SARS-CoV-2-related hospitalization (11.3%) and death (0.9%). Multivariate analysis revealed that only age significantly increased the risk of SARS-CoV-2-related hospitalization. Conclusions: During the Omicron wave, the clinical course of the SARS-CoV-2 infection in KTRs has substantially changed, with lower rates of moderate and severe disease and a low prevalence of adverse outcomes. Prospective clinical trials are warranted to further elucidate the evolving pathogenesis, management, and long-term outcomes of COVID-19 in such high-risk populations.

Association between PIRCHE-II scores and de novo allosensitization after reduction of immunosuppression during SARS-CoV-2 infection in kidney transplant recipients

BACKGROUND

Before the availability of mRNA vaccines, many transplant centers chose to significantly reduce maintenance immunosuppression in kidney transplant recipients (KTRs) with SARS-CoV-2 infection. The extent to which this increases the risk of allosensitization is unclear.

METHODS

In this observational cohort study, we analyzed 47 KTRs from March 2020 to February 2021 who underwent substantial reduction of maintenance immunosuppression during SARS-CoV-2 infection. KTRs were followed at 6 and 18 months concerning the development of de novo donor-specific anti-HLA (human leukocyte antigen) antibodies (DSA). The HLA-derived epitope mismatches were calculated using the predicted indirectly recognizable HLA-epitopes (PIRCHE-II) algorithm.

RESULTS

In total, 14 of 47 KTRs (30%) developed de novo HLA antibodies after the reduction of maintenance immunosuppression. KTRs with higher total PIRCHE-II scores and higher PIRCHE-II scores for the HLA-DR locus were more likely to develop de novo HLA antibodies (p = .023, p = .009). Furthermore, 4 of the 47 KTRs (9%) developed de novo DSA after reduction of maintenance immunosuppression, which were exclusively directed against HLA-class II antigens and also showed higher PIRCHE-II scores for HLA-class II. The cumulative mean fluorescence intensity of 40 KTRs with preexisting anti-HLA antibodies and 13 KTRs with preexisting DSA at the time of SARS-CoV-2 infection remained stable after the reduction of maintenance immunosuppression (p = .141; p = .529).

CONCLUSIONS

Our data show that the HLA-derived epitope mismatch load between donor and recipient influences the risk of de novo DSA development when immunosuppression is temporarily reduced. Our data further suggest that reduction in immunosuppression should be made more cautiously in KTRs with high PIRCHE-II scores for HLA-class II antigens.

Outcomes of SARS-CoV-2 infection among lung transplant recipients: A single center retrospective study

BACKGROUND

Lung transplant recipients (LTRs) are at increased risk for coronavirus disease 2019 (COVID-19)-associated complications.

METHODS

We aimed to describe the outcomes of polymerase chain reaction-documented severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in LTRs followed at our institution from March 2020 to July 2022. The primary outcome investigated was hospitalization or death from COVID-19-related symptoms within 28 days from diagnosis.

RESULTS

Overall, 60 cases were included, of which 18 (30%) reached the primary outcome. Only one patient (2%) died. Anti-spike monoclonal antibodies (mAbs) were administered as early treatment in 36 patients (casirivimab/imdevimab = 2, sotrovimab = 31, and tixagevimab/cilgavimab = 3). Multivariate analysis revealed that age >60 years (p = .003; odds ratio [OR] 9.41; confidence interval [CI] 2.52-41.05) was associated with a higher risk for the primary outcome, while administration of mAbs as early treatment (p = .030; OR 0.23; CI 0.06-0.87) was associated with a lower risk. No effect of vaccination and SARS-CoV-2 variant was observed. Forced expiratory volume in 1 s and forced vital capacity values did not decrease among 37 patients who had spirometry performed 1 month after COVID-19.

CONCLUSIONS

We observed a relatively low morbidity and mortality of COVID-19 in LTR. mAb administration was associated with a better outcome.

Blood Transcriptomes of SARS-CoV-2-Infected Kidney Transplant Recipients Associated with Immune Insufficiency Proportionate to Severity

BACKGROUND

Among patients with COVID-19, kidney transplant recipients (KTRs) have poor outcomes compared with non-KTRs. To provide insight into management of immunosuppression during acute illness, we studied immune signatures from the peripheral blood during and after COVID-19 infection from a multicenter KTR cohort.

METHODS

We ascertained clinical data by chart review. A single sample of blood was collected for transcriptome analysis. Total RNA was poly-A selected and RNA was sequenced to evaluate transcriptome changes. We also measured cytokines and chemokines of serum samples collected during acute infection.

RESULTS

A total of 64 patients with COVID-19 in KTRs were enrolled, including 31 with acute COVID-19 (<4 weeks from diagnosis) and 33 with post-acute COVID-19 (>4 weeks postdiagnosis). In the blood transcriptome of acute cases, we identified genes in positive or negative association with COVID-19 severity scores. Functional enrichment analyses showed upregulation of neutrophil and innate immune pathways but downregulation of T cell and adaptive immune activation pathways. This finding was independent of lymphocyte count, despite reduced immunosuppressant use in most KTRs. Compared with acute cases, post-acute cases showed "normalization" of these enriched pathways after 4 weeks, suggesting recovery of adaptive immune system activation despite reinstitution of immunosuppression. Analysis of the non-KTR cohort with COVID-19 showed significant overlap with KTRs in these functions. Serum inflammatory cytokines followed an opposite trend (i.e., increased with disease severity), indicating that blood lymphocytes are not the primary source.

CONCLUSIONS

The blood transcriptome of KTRs affected by COVID-19 shows decreases in T cell and adaptive immune activation pathways during acute disease that, despite reduced immunosuppressant use, associate with severity. These pathways show recovery after acute illness.

Outcome of COVID-19 in Kidney Transplant Recipients Through the SARS-CoV-2 Variants Eras: Role of Anti-SARS-CoV-2 Monoclonal Antibodies

Kidney transplant recipients (KTR) are at increased risk for COVID-19-associated complications. We aimed to describe the evolving epidemiology and outcome of PCR-documented SARS-CoV-2 infection in KTR followed at our institution from March 2020 to May 2022. The primary endpoint was hospitalization for COVID-19-related symptoms or death within 28 days from diagnosis. Overall, 243 cases were included of which 68 (28%) developed the primary outcome. A significant decrease in the incidence of the primary outcome was observed (p &lt; 0.001, r −0.342) during the study period. Anti-Spike monoclonal antibodies (mAbs) were administered as early treatment (within 5–7 days of onset of symptoms) in 101 patients (14 with casirivimab/imdevimab and 87 with sotrovimab). Among 145 patients who had received at least one vaccination dose before infection, 109 patients were considered as adequately vaccinated. Multivariate analysis revealed that the Charlson Comorbidity Index (P 0.001; OR 1.28, CI 1.11–1.48) was associated with the primary outcome, while early administration of mAbs (P 0.032; OR 0.39, CI 0.16–0.92) was associated with a better outcome, but not infection during the period of the omicron variant predominance or adequate vaccination.

Immunological imprint on peripheral blood in kidney transplant recipients after two doses of SARS-CoV-2 mRNA vaccination in Japan

The immunological imprint after two doses of severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2) mRNA vaccination for patients after kidney transplantation (KTx) remain unclear. This study included KTx recipients and volunteer healthy controls (HCs) who received two doses of SARS-CoV-2 mRNA vaccine (Pfizer BioNTech) from January 2021 to December 2021. We analyzed safety within 21 days after each vaccination dose and compared the immune response in peripheral blood mononuclear cells (PBMCs) between the two groups. No graft rejection was observed throughout this study. Adverse events were generally observed within 5 days. The KTx group exhibited a significantly lower degree of symptoms between doses 1 and 2 (P &lt; 0.001). Increases in activated subsets of T and B cells expressing human leukocyte antigen (HLA)-DR and/or CD38 were observed in the HC group after dose 2 (both P &lt; 0.001), with the greatest increases in HLA-DR+CD8+ T cells and CD38+CD19+ B cells (P = 0.042 and P = 0.031, respectively). In addition, PD1+CD8+ T cells—but not PD1+CD4+ T cells—increased significantly in the HC group (P = 0.027). In the KTx group, however, activated HLA-DR+, CD38+, and PD1+ cells remained at baseline levels. Immunoglobulin (Ig)G against SARS-CoV-2 was detected in only four KTx recipients (13.3%) after dose 2 (P &lt; 0.001). Multivariate logistic regression analyses revealed that ΔHLA-DR+CD8+ T cells and ΔCD38+CD19+ B cells were significantly associated with IgG formation (both P = 0.02). SARS-CoV-2 mRNA vaccine generates impaired cellular and humoral immunity for KTx recipients. Results indicate the need for modified vaccination strategies in immunocompromised KTx recipients.

COVID-19 infection frequency and clinical course in patients with liver transplantation: Results of a single transplant center in Türkiye

Objectives

In this paper, it was tried to determine the incidence of COVID-19, course of the disease, and mortality rate in liver transplant patients by evaluating all patients operated on in our center. In addition, the results of liver transplantation performed in our center during the pandemic period were also presented.

Material and Methods

All patients who had undergone liver transplantation in our liver transplant center were questioned about their history of COVID-19 either at their routine controls in the clinic or by phone interview.

Results

Our liver transplant unit had 195 registered liver transplantation patients (2002-2020), and 142 of these were still alive and under follow-up. During the pandemic period, 80 patients referred to our outpatient clinic for follow-up, and their records were evaluated retrospectively in January 2021. Among 142 liver transplant patients, a total of 18 (12.6%) COVID-19 patients were identified. While 13 of these patients were males, mean age of the patients at the time of interviews was 48.8 years (22-65 years). Nine of the patients had living donor liver transplant, and the rest had cadaveric liver transplant. The most common COVID-19 associated symptom in the patients was fever. During the pandemic period, 12 liver transplant operations were performed in our center. Nine of them were living donor liver transplantation and the remainder were cadaveric liver transplantations. Two of our patients got COVID-19 positive during this period. One of them who was transplanted after COVID treatment was followed-up in intesive care for a long time and was lost not related to COVID-19.

Conclusion

The incidence of COVID-19 is higher in liver transplant patients than in the general population. Nonetheless, mortality rates are low. During the pandemic period, liver transplantation can be continued by following general precautions.

High torque tenovirus (TTV) load before first vaccine dose is associated with poor serological response to COVID-19 vaccination in lung transplant recipients

BACKGROUND

Serological responses to COVID-19 vaccination are diminished in recipients of solid organ transplants, especially in lung transplant recipients (LTR), probably as result of immunosuppressive treatment. There is currently no marker of immunosuppression that can be used to predict the COVID-19 vaccination response. Here, we study whether torque tenovirus (TTV), a highly prevalent virus can be used as an indicator of immunosuppression.

METHODS

The humoral response to the mRNA 1273 vaccine was assessed in 103 LTR, who received a transplant between 4 and 237 months prior to vaccination, by measuring Spike (S)-specific IgG levels at baseline, 28 days after first, and 28 days after the second vaccination. TTV loads were determined by RT-PCR and Pearson's correlation coefficient was calculated to correlate serological responses to TTV load.

RESULTS

Humoral responses to COVID-19 vaccination were observed in 41 of 103 (40%) LTR at 28 days after the second vaccination. Sixty-two of 103 (60%) were non-responders. Lower TTV loads at baseline (significantly) correlated with higher S-specific antibodies and a higher percentage of responders. Lower TTV loads also strongly correlated with longer time since transplantation, indicating that participants with lower TTV loads were longer after transplantation.

CONCLUSIONS

This study shows a better humoral response to the SARS-CoV-2 vaccine in subjects with a lower TTV load pre-vaccination. In addition, TTV load correlates with the time after transplantation. Further studies on the use of TTV load in vaccination efficacy studies in immunocompromised cohorts should provide leads for the potential use of this marker for optimizing vaccination response.

Heterogeneity and Risk of Bias in Studies Examining Risk Factors for Severe Illness and Death in COVID-19: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis synthesized the evidence on the impacts of demographics and comorbidities on the clinical outcomes of COVID-19, as well as the sources of the heterogeneity and publication bias of the relevant studies. Two authors independently searched the literature from PubMed, Embase, Cochrane library, and CINAHL on 18 May 2021; removed duplicates; screened the titles, abstracts, and full texts by using criteria; and extracted data from the eligible articles. The variations among the studies were examined by using Cochrane, Q.; I2, and meta-regression. Out of 11,975 articles that were obtained from the databases and screened, 559 studies were abstracted, and then, where appropriate, were analyzed by meta-analysis (n = 542). COVID-19-related severe illness, admission to the ICU, and death were significantly correlated with comorbidities, male sex, and an age older than 60 or 65 years, although high heterogeneity was present in the pooled estimates. The study design, the study country, the sample size, and the year of publication contributed to this. There was publication bias among the studies that compared the odds of COVID-19-related deaths, severe illness, and admission to the ICU on the basis of the comorbidity status. While an older age and chronic diseases were shown to increase the risk of developing severe illness, admission to the ICU, and death among the COVID-19 patients in our analysis, a marked heterogeneity was present when linking the specific risks with the outcomes.

Characteristics and Outcomes of Heart Transplant Recipients With Coronavirus-19 Disease in a High-volume Transplant Center

BACKGROUND

Heart transplant (HT) recipients may be at higher risk of acquiring SARS-CoV-2 infection and developing critical illness. The aim of this study is to describe characteristics and outcomes of HT recipients infected by SARS-COV-2, from a high-volume transplant center.

METHODS

We have described data of all adult HT recipients with confirmed coronavirus disease 2019 by RT-PCR in nasopharyngeal samples from April 5, 2020, to January 5, 2021. Outcomes and follow-up were recorded until February 5, 2021.

RESULTS

Forty patients were included. Twenty-four patients (60%) were men; the median age was 53 (40-60) y old; median HT time was 34 mo; and median follow-up time 162 d. The majority needed hospitalization (83%). Immunosuppressive therapy was reduced/withdrawn in the majority of patients, except from steroids, which were maintained. Seventeen patients (42.5%) were classified as having severe disease according to the ordinal scale developed by the World Health Organization Committee. They tended to have lower absolute lymphocyte count (P < 0.001) during follow-up when compared with patients with mild disease. Thirty-day mortality was 12.5%. However, a longer follow-up revealed increased later mortality (27.5%), with median time to death around 35 d. Bacterial nosocomial infections were a leading cause of death. Cardiac allograft rejection (10%) and ventricular dysfunction (12.5%) were also not negligible.

CONCLUSIONS

Major findings of this study corroborate other cohorts' results, but it also reports significant rate of later events, suggesting that a strict midterm surveillance is advisable to HT recipients with coronavirus disease 2019.

COVID-19: Gastrointestinal manifestations, liver injury and recommendations

Coronavirus disease 2019 (COVID-19) has caused a pandemic that affected all countries with nearly 270 million patients and 5 million deaths, as of as of December, 2021. The severe acute respiratory syndrome coronavirus 2 virus targets the receptor, angiotensin-converting enzyme 2, which is frequently found in human intestinal epithelial cells, bile duct epithelial cells, and liver cells, and all gastrointestinal system organs are affected by COVID-19 infection. The aim of this study is to review the gastrointestinal manifestations and liver damage of COVID-19 infection and investigate the severe COVID-19 infection risk in patients that have chronic gastrointestinal disease, along with current treatment guidelines. A literature search was conducted on electronic databases of PubMed, Scopus, and Cochran Library, consisting of COVID-19, liver injury, gastrointestinal system findings, and treatment. Liver and intestinal involvements are the most common manifestations. Diarrhea, anorexia, nausea/vomiting, abdominal pain are the most frequent symptoms seen in intestinal involvement. Mild hepatitis occurs with elevated levels of transaminases. Gastrointestinal involvement is associated with long hospital stay, severity of the disease, and intensive care unit necessity. Treatments and follow-up of patients with inflammatory bowel diseases, cirrhosis, hepatocellular carcinoma, or liver transplant have been negatively affected during the pandemic. Patients with cirrhosis, hepatocellular carcinoma, auto-immune diseases, or liver transplantation may have a greater risk for severe COVID-19. Diagnostic or therapeutic procedures should be restricted with specific conditions. Telemedicine should be used in non-urgent periodic patient follow up. COVID-19 treatment should not be delayed in patients at the risk group. COVID-19 vaccination should be prioritized in this group.

Blood transcriptomes of SARS-CoV-2 infected kidney transplant recipients demonstrate immune insufficiency

BACKGROUND

Kidney transplant recipients (KTRs) with COVID-19 have poor outcomes compared to non-KTRs. To provide insight into management of immunosuppression during acute illness, we studied immune signatures from the peripheral blood during and after COVID-19 infection from a multicenter KTR cohort.□.

METHODS

Clinical data were collected by chart review. PAXgene blood RNA was poly-A selected and RNA sequencing was performed to evaluate transcriptome changes.

RESULTS

A total of 64 cases of COVID-19 in KTRs were enrolled, including 31 acute cases (< 4 weeks from diagnosis) and 33 post-acute cases (>4 weeks). In the blood transcriptome of acute cases, we identified differentially expressed genes (DEGs) in positive or negative association COVID-19 severity scores. Functional enrichment analyses showed upregulation of neutrophil and innate immune pathways, but downregulation of T-cell and adaptive immune-activation pathways proportional to severity score. This finding was independent of lymphocyte count and despite reduction in immunosuppression (IS) in most KTRs. Comparison with post-acute cases showed "normalization" of these enriched pathways after >4 weeks, suggesting recovery of adaptive immune system activation despite reinstitution of IS. The latter analysis was adjusted for COVID-19 severity score and lymphocyte count. DEGs associated with worsening disease severity in a non-KTR cohort with COVID-19 (GSE152418) showed significant overlap with KTRs in these identified enriched pathways.

CONCLUSION

Blood transcriptome of KTRs affected by COVID-19 shows decrease in T-cell and adaptive immune activation pathways during acute disease that associate with severity despite IS reduction and show recovery after acute illness.

SIGNIFICANCE STATEMENT

Kidney transplant recipients (KTRs) are reported to have worse outcomes with COVID-19, and empiric reduction of maintenance immunosuppression is pursued. Surprisingly, reported rates of acute rejection have been low despite reduced immunosuppression. We evaluated the peripheral blood transcriptome of 64 KTRs either during or after acute COVID-19. We identified transcriptomic signatures consistent with suppression of adaptive T-cell responses which significantly associated with disease severity and showed evidence of recovery after acute disease, even after adjustment for lymphocyte number. Our transcriptomic findings of immune-insufficiency during acute COVID-19 provide an explanation for the low rates of acute rejection in KTRs despite reduced immunosuppression. Our data support the approach of temporarily reducing T -cell-directed immunosuppression in KTRs with acute COVID-19.

Global impact of the first wave of COVID-19 on liver transplant centers: A multi-society survey (EASL-ESOT/ELITA-ILTS)

BACKGROUND AND AIMS

The global impact of SARS-CoV-2 on liver transplantation (LT) practices across the world is unknown. The goal of this survey was to assess the impact of the pandemic on global LT practices.

METHOD

A prospective web-based survey (available online from 7^th September 2020 to 31^st December 2020) was proposed to the active members of the EASL-ESOT/ELITA-ILTS in the Americas (including North, Central, and South America) (R1), Europe (R2), and the rest of the world (R3). The survey comprised 4 parts concerning transplant processes, therapy, living donors, and organ procurement.

RESULTS

Of the 470 transplant centers reached, 128 answered each part of the survey, 29 centers (23%), 64 centers (50%), and 35 centers (27%) from R1, R2, and R3, respectively. When we compared the practices during the first 6 months of the pandemic in 2020 with those a year earlier in 2019, statistically significant differences were found in the number of patients added to the waiting list (WL), WL mortality, and the number of LTs performed. At the regional level, we found that in R2 the number of LTs was significantly higher in 2019 (p <0.01), while R3 had more patients listed, higher WL mortality, and more LTs performed before the pandemic. Countries severely affected by the pandemic ("hit" countries) had a lower number of WL patients (p = 0.009) and LTs (p = 0.002) during the pandemic. Interestingly, WL mortality was still higher in the "non-hit" countries in 2020 compared to 2019 (p = 0.022).

CONCLUSION

The first wave of the pandemic differentially impacted LT practices across the world, especially with detrimental effects on the "hit" countries. Modifications to the policies of recipient and donor selection, organ retrieval, and postoperative recipient management were adopted at a regional or national level.

LAY SUMMARY

The health emergency caused by the coronavirus pandemic has dramatically changed clinical practice during the pandemic. The first wave of the pandemic impacted liver transplantation differently across the world, with particularly detrimental effects on the countries badly hit by the virus. The resilience of the entire transplant network has enabled continued organ donation and transplantation, ultimately improving the lives of patients with end-stage liver disease.

Viral infections in lung transplantation

Viral infections account for up to 30% of all infectious complications in lung transplant recipients, remaining a significant cause of morbidity and even mortality. Impact of viral infections is not only due to the direct effects of viral replication, but also to immunologically-mediated lung injury that may lead to acute rejection and chronic lung allograft dysfunction. This has particularly been seen in infections caused by herpesviruses and respiratory viruses. The implementation of universal preventive measures against cytomegalovirus (CMV) and influenza (by means of antiviral prophylaxis and vaccination, respectively) and administration of early antiviral treatment have reduced the burden of these diseases and potentially their role in affecting allograft outcomes. New antivirals against CMV for prophylaxis and for treatment of antiviral-resistant CMV infection are currently being evaluated in transplant recipients, and may continue to improve the management of CMV in lung transplant recipients. However, new therapeutic and preventive strategies are highly needed for other viruses such as respiratory syncytial virus (RSV) or parainfluenza virus (PIV), including new antivirals and vaccines. This is particularly important in the advent of the COVID-19 pandemic, for which several unanswered questions remain, in particular on the best antiviral and immunomodulatory regimen for decreasing mortality specifically in lung transplant recipients. In conclusion, the appropriate management of viral complications after transplantation remain an essential step to continue improving survival and quality of life of lung transplant recipients.

COVID-19 in Immunocompromised Patients: A Systematic Review

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was first identified as a novel coronavirus in Wuhan, Hubei province, central China, in December 2019, and is responsible for the 2019-to-present pandemic. According to the most recent data released by the World Health Organization, more than 200 million people have been infected by SARS-CoV-2 so far, and more than 4 million people died worldwide. Although our knowledge on SARS-CoV-2 and COVID-19 is constantly growing, data on COVID-19 in immunocompromised patients are still limited. The aim of the present systematic review is to describe clinical picture, disease severity, proposed treatment regimen, and response to vaccination in patients with different types and severity of immunosuppression.

Cohort profile: The Swiss Transplant Cohort Study (STCS): A nationwide longitudinal cohort study of all solid organ recipients in Switzerland

PURPOSE

The Swiss Transplant Cohort Study (STCS) is a prospective multicentre cohort study which started to actively enrol study participants in May 2008. It takes advantage of combining data from all transplant programmes in one unique system to perform comprehensive nationwide reporting and to promote translational and clinical post-transplant outcome research in the framework of Swiss transplantation medicine.

PARTICIPANTS

Over 5500 solid organ transplant recipients have been enrolled in all six Swiss transplant centres by end of 2019, around three-quarter of them for kidney and liver transplants. Ninety-three per cent of all transplanted recipients have consented to study participation, almost all of them (99%) contributed to bio-sampling. The STCS genomic data set includes around 3000 patients.

FINDINGS TO DATE

Detailed clinical and laboratory data in high granularity as well as patient-reported outcomes from transplant recipients and activities in Switzerland are available in the last decade. Interdisciplinary contributions in diverse fields of transplantation medicine such as infectious diseases, genomics, oncology, immunology and psychosocial science have resulted in approximately 70 scientific papers getting published in peer-review journals so far.

FUTURE PLANS

The STCS will deepen its efforts in personalised medicine and digital epidemiology, and will also focus on allocation research and the use of causal inference methods to make complex matters in transplant medicine more understandable and transparent.

COVID-19 in renal transplant recipients and general population: a comparative study of clinical, laboratory, and radiological features, severity, and outcome

INTRODUCTION

Coronavirus disease 2019 (COVID-19), a novel disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to millions of deaths worldwide. Kidney transplant recipients (KTRs) are a fragile population due to their immunosuppressed status. However, there are limited studies available comparing this population with the general population regarding clinical symptoms, and laboratory and imaging features as well as disease severity and clinical outcomes.

METHODS

A total of 24 KTRs and 40 patients from the general population (control group) were enrolled after applying exclusion criteria. Clinical symptoms, laboratory values, and lung involvement patterns in high-resolution computed tomography (HRCT) were compared between KTRs with COVID-19 and their counterparts from the general population. Moreover, the category of disease severity and adverse outcomes such as intensive care unit (ICU) admission, mechanical ventilation (MV), and mortality rate were also compared between these two groups.

RESULTS

Hypertension was significantly higher among KTRs. Dyspnea was significantly more among the control group (P = 0.045). There was no significant difference in the rest of clinical symptoms (P > 0.05). There was no significant difference in CT features as well, except pleural effusion, which was more prevalent in the control group. A lower absolute lymphocytic count (ALC) and platelet count were observed in KTRs. Renal transplant recipients (RTRs) had a higher elevation in creatinine level than their counterparts. The ICU admission, MV, duration of hospital stay, and mortality as adverse outcomes were not significantly different between the KTR and control groups.

CONCLUSION

In conclusion, there was no significant difference in the severity and risk of adverse outcomes, including MV, ICU admission, and mortality between KTRs under chronic immunosuppression and the control group.

DCcov: Repositioning of drugs and drug combinations for SARS-CoV-2 infected lung through constraint-based modeling

The 2019 coronavirus disease (COVID-19) became a worldwide pandemic with currently no approved effective antiviral drug. Flux balance analysis (FBA) is an efficient method to analyze metabolic networks. Here, FBA was applied on human lung cells infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to reposition metabolic drugs and drug combinations against the virus replication within the host tissue. Making use of expression datasets of infected lung tissue, genome-scale COVID-19-specific metabolic models were reconstructed. Then, host-specific essential genes and gene pairs were determined through in silico knockouts that permit reducing the viral biomass production without affecting the host biomass. Key pathways that are associated with COVID-19 severity in lung tissue are related to oxidative stress, ferroptosis, and pyrimidine metabolism. By in silico screening of Food and Drug Administration (FDA)-approved drugs on the putative disease-specific essential genes and gene pairs, 85 drugs and 52 drug combinations were predicted as promising candidates for COVID-19 (https://github.com/sysbiolux/DCcov).

Predictors and outcomes of respiratory failure among lung transplant patients with COVID-19

BACKGROUND

There is limited data on the predictors and outcomes of new or worsening respiratory failure among lung transplant (LT) patients with Coronavirus disease 2019 (COVID-19).

METHODS

We included all the LT patients diagnosed with COVID-19 during a 1-year period (March 2020 to February 2021; n = 54; median age: 60, 20-73 years; M:F 37:17). Development of new or worsening respiratory failure (ARF) was the primary outcome variable.

RESULTS

The overall incidence of ARF was 48.1% (n = 26). More than 20% of patients (n = 11) needed intubation and mechanical ventilation. Body mass index > 25 Kg/m² (adjusted OR: 5.7, .99-32.93; P = .05) and peak D-dimer levels > .95 mcg/ml (adjusted OR: 24.99, 1.77-353.8; P = .017) were independently associated with ARF while anticoagulation use prior to COVID-19 was protective (adjusted OR: .024, .001-.55; P = .02). Majority patients survived the acute illness (85.2%). Pre-infection chronic lung allograft dysfunction (CLAD) was an independent predictor of mortality (adjusted HR: 5.03, 1.14-22.25; P = .033).

CONCLUSIONS

COVID-19 is associated with significant morbidity and mortality among LT patients. Patients on chronic anticoagulation seem to enjoy favorable outcomes, while higher BMI and peak D-dimer levels are associated with development of ARF. Pre-infection CLAD is associated with an increased risk of death from COVID-19.

Coronavirus Disease 2019 (COVID-19) in Solid Organ Transplant Recipients: A Case-Control Study

Background

It is unclear whether solid organ transplant (SOT) patients have more severe coronavirus disease 2019 (COVID-19) and worse outcome than the general population.

Material/Methods

We conducted a case-control study on 32 SOT recipients and 84 non-SOT controls matched for age and sex admitted for confirmed COVID-19. The primary endpoint was in-hospital all-cause mortality rate. Secondary endpoints included severe acute respiratory distress syndrome (ARDS), use of high-flow oxygen therapy, and length of hospital stay.

Results

The median (IQR) Charlson comorbidity index (CCI) at admission was significantly higher in SOT recipients (6 (3–8) vs 3 (2–4); P<0.01). Fever was less frequent in SOT recipients (78% vs 94%, P=0.01). SOT recipients had a higher median SaO2/FiO2 at admission (452 [443–462] vs 443 [419–452], P<0.01) and reached the worst SaO2/FiO2 value later during hospitalization 15 (10–21) vs 11 (9–14) days, P=0.01). Both groups had a similar severe ARDS rate during hospitalization (33% vs 28%) (p=0.59). There were no significant differences during hospitalization in terms of highest level of respiratory support needed, or length of hospital stay: 8.5 (5.5–21) vs 11.5 (6.5–16.5) days; P=0.34) in SOT recipients when compared to controls. In-hospital all-cause mortality rates were significantly higher in SOT recipients (21.9% vs 4.7%, P<0.01; OR 1.08; 95% CI 0.10–10.98), but among patients who died, median CCI was similar between groups (8 [6–8] vs 7 [6–8]).

Conclusions

In our experience, hospitalized SOT recipients for COVID-19 had higher in-hospital mortality compared to non-SOT patients, probably due to the greater number of underlying comorbidities, and not directly related to chronic immunosuppression.

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.

SARS-CoV-2 in Solid Organ Transplant Recipients: A Structured Review of 2020

BACKGROUND

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is challenging health systems all over the world. Particularly high-risk groups show considerable mortality rates after infection. In 2020, a huge number of case reports, case series, and consecutively various systematic reviews have been published reporting on morbidity and mortality risk connected with SARS-CoV-2 in solid organ transplant (SOT) recipients. However, this vast array of publications resulted in an increasing complexity of the field, overwhelming even for the expert reader.

METHODS

We performed a structured literature review comprising electronic databases, transplant journals, and literature from previous systematic reviews covering the entire year 2020. From 164 included articles, we identified 3451 cases of SARS-CoV-2-infected SOT recipients.

RESULTS

Infections resulted in a hospitalization rate of 84% and 24% intensive care unit admissions in the included patients. Whereas 53.6% of patients were reported to have recovered, cross-sectional overall mortality reported after coronavirus disease 2019 (COVID-19) was at 21.1%. Synoptic data concerning immunosuppressive medication attested to the reduction or withdrawal of antimetabolites (81.9%) and calcineurin inhibitors (48.9%) as a frequent adjustment. In contrast, steroids were reported to be increased in 46.8% of SOT recipients.

CONCLUSIONS

COVID-19 in SOT recipients is associated with high morbidity and mortality worldwide. Conforming with current guidelines, modifications of immunosuppressive therapies mostly comprised a reduction or withdrawal of antimetabolites and calcineurin inhibitors, while frequently maintaining or even increasing steroids. Here, we provide an accessible overview to the topic and synoptic estimates of expectable outcomes regarding in-hospital mortality of SOT recipients with COVID-19.

Trends in Heart and Lung Transplantation in the United States Across the COVID-19 Pandemic

The coronavirus disease 2019 (COVID-19) pandemic has had a variable course across the United States. Understanding its evolving impact on heart and lung transplantation (HT and LT) will help with planning for next phases of this pandemic as well as future ones.

METHODS

We used Scientific Registry of Transplant Recipients data from before the pandemic to predict the number of waitlist registrations and transplants expected to occur between March 15, 2020, and December 31, 2020 (if no pandemic had occurred), and compared these expectations to observed rates. The observed era was divided into wave 1 (March 15-May 31), wave 2 (June 1-September 30), and wave 3 (October 1-December 31). We used multilevel Poisson regression to account for center- and state-level COVID-19 incidence.

RESULTS

During wave 1, rates of heart registrations and transplants were 28% (incidence rate ratio [IRR]: 0.72 [95% confidence interval (CI), 0.67-0.77]) and 13% (IRR: 0.87 [95% CI, 0.80-0.93]) lower than expected; lung registrations and transplants were 40% (IRR: 0.60 [95% CI, 0.54-0.66]) and 28% (IRR: 0.72 [95% CI, 0.66-0.79]) lower. Decreases were greatest in states with the highest incidence where registrations were 53% (IRR: 0.47 [95% CI, 0.36-0.62]) and 59% (IRR: 0.41 [95% CI, 0.29-0.58]) and transplants were 57% (IRR: 0.43 [95% CI, 0.31-0.60]) and 58% (IRR: 0.42 [95% CI, 0.29-0.62]) lower than expected. Whereas HT largely recovered during waves 2 and 3, LT continued to fall short of expectations through the end of the year.

CONCLUSIONS

The COVID-19 pandemic in the US substantially reduced thoracic transplant access. Ongoing evaluation of the risks and benefits of this dramatic practice change is critical to inform clinical decision-making moving forward.

Impact of COVID-19 on Lung Allograft and Clinical Outcomes in Lung Transplant Recipients: A Case-control Study

BACKGROUND

The impacts of COVID-19 on lung allograft function, rejection, secondary infection, and clinical outcomes in lung transplant recipients (LTRs) remain unknown.

METHODS

A 1:2 matched case-control study was performed to evaluate rehospitalization, lung allograft function, and secondary infections up to 90 d after COVID-19 diagnosis (or index dates for controls).

RESULTS

Twenty-four LTRs with COVID-19 (cases) and 48 controls were identified. Cases and controls had similar baseline characteristics and lung allograft function. LTRs with COVID-19 had higher incidence of secondary bacterial infection (29.2% versus 6.3%, P = 0.008), readmission (29.2% versus 10.4%, P = 0.04), and for-cause bronchoscopy (33.3% versus 12.5%, P = 0.04) compared with controls. At d 90, mortality in cases versus controls was 8.3% versus 2.1% (P = 0.21), incidence of invasive fungal infections in cases versus controls was 20.8% versus 8.3% (P = 0.13) and forced expiratory volume in 1 s (FEV1) decline ≥10% from baseline occurred in 19% of cases versus 12.2% of controls (P = 0.46). No acute cellular rejection, acute antibody-mediated rejection, or new donor-specific anti-HLA antibodies were observed among cases or controls within 90 d post index date.

CONCLUSIONS

We found LTRs with COVID-19 were at risk to develop secondary infections and rehospitalization post COVID-19, compared with controls. While we did not observe post viral acute cellular rejection or antibody-mediated rejection, further studies are needed to understand if LTRs with COVID-19 who did not recover baseline lung function within 90 d have developed chronic lung allograft dysfunction stage progression.

Liver transplant in a recently COVID-19 positive child with hepatoblastoma

We describe the successful pediatric liver transplant for unresectable hepatoblastoma in a 4-year-old male with COVID-19 prior to transplant. The first negative NP swab was documented 1 month after initial diagnosis, when SARS-CoV-2 antibodies were also detected. The patient was actively listed for liver transplant after completing four blocks of a SIOPEL-4 based regimen due to his PRETEXT IV disease which remained unresectable. Following three additional negative NP swabs and resolution of symptoms for 4 weeks, he underwent a whole-organ pediatric liver transplant. COVID-19 positivity determined via NP swab SARS-CoV-2 real-time RT-PCR (Hologic Aptima SARS-CoV-2 RT-PCR assay). IgG and IgM total SARS- CoV-2 antibodies detected by Ortho Clinical Diagnostics VITROS® Immunodiagnostics Products Anti-SARS-CoV-2 Test. Patient received standard prednisone and tacrolimus-based immunosuppression without induction therapy following transplant. Post-transplant course was remarkable for neutropenia and thrombocytopenia, with discharge home on post-transplant day #11. Surveillance tests have remained negative with persistent SARS-CoV-2 IgG antibodies at 6 weeks after transplant. We describe one of the earliest, if not the first case of liver transplant following recent recovery from COVID-19 in a pediatric patient with a lethal malignant liver tumor. A better understanding of how to balance the risk profile of transplant in the setting of COVID-19 with disease progression if transplant is not performed is needed. We followed existing ASTS guidelines to document clearance of the viral infection and resolution of symptoms before transplant. This case highlights that pediatric liver transplantation can be safely performed upon clearance of COVID-19.

SARS-CoV-2 and pediatric solid organ transplantation: Current knowns and unknowns

The COVID-19 pandemic has proven to be a challenge in regard to the clinical presentation, prevention, diagnosis, and management of SARS-CoV-2 infection among children who are candidates for and recipients of SOT. By providing scenarios and frequently asked questions encountered in routine clinical practice, this document provides expert opinion and summarizes the available data regarding the prevention, diagnosis, and management of SARS-CoV-2 infection among pediatric SOT candidates and recipients and highlights ongoing knowledge gaps requiring further study. Currently available data are still lacking in the pediatric SOT population, but data have emerged in both the adult SOT and general pediatric population regarding the approach to COVID-19. The document provides expert opinion regarding prevention, diagnosis, and management of SARS-CoV-2 infection among pediatric SOT candidates and recipients.

Inpatient COVID-19 outcomes in solid organ transplant recipients compared to non-solid organ transplant patients: A retrospective cohort

Immunosuppression and comorbidities might place solid organ transplant (SOT) recipients at higher risk from COVID-19, as suggested by recent case series. We compared 45 SOT vs. 2427 non-SOT patients who were admitted with COVID-19 to our health-care system (March 1, 2020 - August 21, 2020), evaluating hospital length-of-stay and inpatient mortality using competing-risks regression. We compared trajectories of WHO COVID-19 severity scale using mixed-effects ordinal logistic regression, adjusting for severity score at admission. SOT and non-SOT patients had comparable age, sex, and race, but SOT recipients were more likely to have diabetes (60% vs. 34%, p < .001), hypertension (69% vs. 44%, p = .001), HIV (7% vs. 1.4%, p = .024), and peripheral vascular disorders (19% vs. 8%, p = .018). There were no statistically significant differences between SOT and non-SOT in maximum illness severity score (p = .13), length-of-stay (sHR: _0.9 1.1_1.4 , p = .5), or mortality (sHR: _0.1 0.4_1.6 , p = .19), although the severity score on admission was slightly lower for SOT (median [IQR] 3 [3, 4]) than for non-SOT (median [IQR] 4 [3-4]) (p = .042) Despite a higher risk profile, SOT recipients had a faster decline in disease severity over time (OR = _0.76 0.81_0.86 , p < .001) compared with non-SOT patients. These findings have implications for transplant decision-making during the COVID-19 pandemic, and insights about the impact of SARS-CoV-2 on immunosuppressed patients.

COVID-19 in Solid Organ Transplant Recipients: a Review of the Current Literature

Purpose of review

The approach to ongoing organ transplantation and management of COVID-19 in solid organ transplant recipients (SOTR) has evolved tremendously since the pandemic’s beginning. We summarize the current literature surrounding the virology of SARS-CoV-2, epidemiology of COVID-19 in transplant recipients, review the clinical features and complications of COVID-19 in SOTR, and discuss the safety and efficacy of current therapies and candidate vaccines in this population.

Recent findings

Despite initial suspensions in organ transplantation during early 2020, routine donor testing and de-crowding of hospitals have allowed transplant activity to resume at pre-pandemic rates. COVID-19-associated mortality in SOTR is similar to that of the general population, and lower than that of patients with end-organ disease awaiting transplant. The optimal approach to immunosuppression in SOTR with COVID-19 is unknown and disease severity may influence management decisions. Many vaccines in development are likely to be safe for immunocompromised hosts, though post-marketing investigations will be required to determine the efficacy in the SOTR.

Summary

Though there are multiple unique considerations in the care of SOTR with COVID-19, immunosuppression does not appear to have a detrimental impact on overall outcome. Organ transplantation remains a lifesaving intervention and can be safely performed despite a global pandemic.

COVID-19 in heart transplant recipients during February-August 2020: A systematic review

The coronavirus disease 2019 (COVID-19) pandemic represents a major concern in immunosuppressed patients such as heart transplant recipients. Therefore, we performed a systematic review to summarize the clinical features, treatment, and outcomes of heart transplant recipients with COVID-19. We searched electronic databases from inception to January 11, 2021. Thirty-nine articles (22 case reports and 17 cohorts) involving 415 patients were included. The mean age was 59.9 ± 15.7 years and 77% of patients were men. In cohort studies including outpatients and inpatients, the hospitalization rate was 77%. The most common symptoms were fever (70%) and cough (67%). Inflammatory biomarkers (C-reactive protein and procalcitonin) were above the normal range. Forty-eight percent of patients presented with severe or critical COVID-19. Hydroxychloroquine (54%), azithromycin (14%), and lopinavir/ritonavir (14%) were the most commonly used drugs. Forty-nine percent of patients discontinued the baseline regimen of antimetabolites. In contrast, 59% and 73% continued the same regimen of calcineurin inhibitors and corticosteroids, respectively. Short-term mortality among cohorts limited to inpatients was 25%. Our review suggests that heart transplant recipients with COVID-19 exhibited similar demographic and clinical features to the general population. However, the prognosis was poor in these patients.

Covid-19 in end-stage renal disease patients with renal replacement therapies: A systematic review and meta-analysis

Background

The novel coronavirus (COVID-19), caused by SARS-CoV-2, showed various prevalence and case-fatality rates (CFR) among patients with different pre-existing chronic conditions. End-stage renal disease (ESRD) patients with renal replacement therapy (RRT) might have a higher prevalence and CFR due to reduced immune function from uremia and kidney tropism of SARS-CoV-2, but there was a lack of systematic study on the infection and mortality of the SARS-CoV-2 infection in ESRD patients with various RRT.

Methodology/Principal findings

We searched five electronic databases and performed a systematic review and meta-analysis up to June 30, 2020, to evaluate the prevalence and case fatality rate (CFR) of the COVID-19 infection among ESRD patients with RRT. The global COVID-19 data were retrieved from the international database on June 30, 2020, for estimating the prevalence and CFR of the general population as referencing points. Of 3,272 potential studies, 34 were eligible studies consisted of 1,944 COVID-19 confirmed cases in 21,873 ESRD patients with RRT from 12 countries in four WHO regions. The overall pooled prevalence in ESRD patients with RRT was 3.10% [95% confidence interval (CI) 1.25–5.72] which was higher than referencing 0.14% global average prevalence. The overall estimated CFR of COVID-19 in ESRD patients with RRT was 18.06% (95% CI 14.09–22.32) which was higher than the global average at 4.98%.

Conclusions

This meta-analysis suggested high COVID-19 prevalence and CFR in ESRD patients with RRT. ESRD patients with RRT should have their specific protocol of COVID-19 prevention and treatment to mitigate excess cases and deaths.

Chronic kidney disease (CKD) was associated with increasing severity and mortality of COVID-19. End-stage renal disease (ESRD) patients were at the terminal stage of CKD and had reduced immune function due to uremia. Additionally, ESRD patients with kidney transplantation had a diminished immune system from immunosuppressive agents. Kidneys might be the secondary target of SARS-CoV-2 after the respiratory tract regardless of the previous history of kidney disease, preferably the glomerulus, which was associated with the richness of some specific protein-coding genes in the kidney. The overall pooled prevalence in ESRD patients with renal replacement therapy was approximately 22 times the referencing global average prevalence. The overall estimated case fatality rate of COVID-19 in ESRD patients with renal replacement therapy was approximately 3.6 times the global average. ESRD patients with renal replacement therapy had high COVID-19 prevalence and case fatality rate. We suggested that ESRD patients with renal replacement therapy should have their specific protocol of COVID-19 prevention and treatment to mitigate excess cases and deaths.

Pediatric liver and kidney transplantation in the era of COVID-19: a follow-up study from a tertiary referral center in Iran

BACKGROUND

We aimed to evaluate the impact of COVID-19 pandemic on pediatric transplant outcomes and determine whether to continue pediatric transplant activity or not, and how policies intended our center has been effective in preventing COVID-19 among organ transplant recipients.

METHODS

We conducted a single-center, retrospective, cohort study of hospitalized pediatrics after organ transplantation at Shiraz transplant center since March to August 2020. All liver and kidney transplanted children were included the study and their laboratory and clinical related COVID-19 characteristics were followed up till 3 months after transplantation during hospitalization period and then weekly by the transplant committee.

RESULTS

Fifty-one patients underwent transplantation including 11 kidney and 40 liver recipients. The mean age of the pediatric cases was 6.72 ± 5.47 years. A total of 11 patients died due to post-transplant complications, while none of the patients presented any sign or symptoms in favor of COVID-19 in the hospital course after transplantation. Six transplants including 2 kidney and 4 liver were canceled when positive PCR tests were detected in their donors before the surgery. In the 3 months of follow up, two patients presented with symptoms including high grade fever, malaise, rhinorrhea, and GI symptoms. Both patients had two negative PCR, and no radiologic or laboratory results regarding COVID-19 were also detected. One had positive influenza PCR, while the second one had a positive serologic test for EBV; CT, computed tomography CONCLUSION: Transplant programs could continue their activities during the COVID-19 pandemic with specific case selection, accurate screening methods and following protective protocols.

The pediatric solid organ transplant experience with COVID-19: An initial multi-center, multi-organ case series

The clinical course of COVID-19 in pediatric solid organ transplant recipients remains ambiguous. Though preliminary experiences with adult transplant recipients have been published, literature centered on the pediatric population is limited. We herein report a multi-center, multi-organ cohort analysis of COVID-19-positive transplant recipients ≤ 18 years at time of transplant. Data were collected via institutions' respective electronic medical record systems. Local review boards approved this cross-institutional study. Among 5 transplant centers, 26 patients (62% male) were reviewed with a median age of 8 years. Six were heart recipients, 8 kidney, 10 liver, and 2 lung. Presenting symptoms included cough (n = 12 (46%)), fever (n = 9 (35%)), dry/sore throat (n = 3 (12%)), rhinorrhea (n = 3 (12%)), anosmia (n = 2 (8%)), chest pain (n = 2 (8%)), diarrhea (n = 2 (8%)), dyspnea (n = 1 (4%)), and headache (n = 1 (4%)). Six patients (23%) were asymptomatic. No patient required supplemental oxygen, intubation, or ECMO. Eight patients (31%) were hospitalized at time of diagnosis, 3 of whom were already admitted for unrelated problems. Post-transplant immunosuppression was reduced for only 2 patients (8%). All symptomatic patients recovered within 7 days. Our multi-institutional experience suggests the prognoses of pediatric transplant recipients infected with COVID-19 may mirror those of immunocompetent children, with infrequent hospitalization and minimal treatment, if any, required.

Use of Anti-Cytokine Therapy in Kidney Transplant Recipients with COVID-19

In the context of the coronavirus disease 2019 (COVID-19) pandemic, we aimed to evaluate the impact of anti-cytokine therapies (AT) in kidney transplant recipients requiring hospitalization due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This is an observational retrospective study, which included patients from March to May 2020. An inverse probability of treatment weighting from a propensity score to receive AT was used in all statistical analyses, and we applied a bootstrap procedure in order to calculate an estimation of the 2.5th and 97.5th percentiles of odds ratio (OR). outcomes were measured using an ordinal scale determination (OSD). A total of 33 kidney recipients required hospitalization and 54% of them received at least one AT, mainly tocilizumab (42%), followed by anakinra (12%). There was no statistical effect in terms of intensive care unit (ICU) admission, respiratory secondary infections (35% vs. 7%) or mortality (16% vs. 13%) comparing patients that received AT with those who did not. Nevertheless, patients who received AT presented better outcomes during hospitalization in terms of OSD ≥5 ((OR 0.31; 2.5th, 97.5th percentiles (0.10; 0.72)). These analyses indicate, as a plausible hypothesis, that the use of AT in kidney transplant recipients presenting with COVID-19 could be beneficial, even though multicenter randomized control trials using these therapies in transplanted patients are needed.

Management of lung transplantation in the COVID-19 era-An international survey

It is unknown if solid organ transplant recipients are at higher risk for severe COVID-19. The management of a lung transplantation (LTx) program and the therapeutic strategies to adapt the immunosuppressive regimen and antiviral measures is a major issue in the COVID-19 era, but little is known about worldwide practice. We sent out to 180 LTx centers worldwide in June 2020 a survey with 63 questions, both regarding the management of a LTx program in the COVID-19 era and the therapeutic strategies to treat COVID-19 LTx recipients. We received a total of 78 responses from 15 countries. Among participants, 81% declared a reduction of the activity and 47% restricted LTx for urgent cases only. Sixteen centers observed deaths on waiting listed patients and eight centers performed LTx for COVID-19 disease. In 62% of the centers, COVID-19 was diagnosed in LTx recipients, most of them not severe cases. The most common immunosuppressive management included a decreased dose or pausing of the cell cycle inhibitors. Remdesivir, hydroxychloroquine, and azithromycin were the most proposed antiviral strategies. Most of the centers have been affected by the COVID-19 pandemic and proposed an active therapeutic strategy to treat LTx recipients with COVID-19.

Clinical manifestations and outcomes of coronavirus disease-19 in heart transplant recipients: a multicentre case series with a systematic review and meta-analysis

Available data on clinical presentation and mortality of coronavirus disease‐2019 (COVID‐19) in heart transplant (HT) recipients remain limited. We report a case series of laboratory‐confirmed COVID‐19 in 39 HT recipients from 3 French heart transplant centres (mean age 54.4 ± 14.8 years; 66.7% males). Hospital admission was required for 35 (89.7%) cases including 14/39 (35.9%) cases being admitted in intensive care unit. Immunosuppressive medications were reduced or discontinued in 74.4% of the patients. After a median follow‐up of 54 (19–80) days, death and death or need for mechanical ventilation occurred in 25.6% and 33.3% of patients, respectively. Elevated C‐reactive protein and lung involvement ≥50% on chest computed tomography (CT) at admission were associated with an increased risk of death or need for mechanical ventilation. Mortality rate from March to June in the entire 3‐centre HT recipient cohort was 56% higher in 2020 compared to the time‐matched 2019 cohort (2% vs. 1.28%, P = 0.15). In a meta‐analysis including 4 studies, pre‐existing diabetes mellitus (OR 3.60, 95% CI 1.43–9.06, I² = 0%, P = 0.006) and chronic kidney disease stage III or higher (OR 3.79, 95% CI 1.39–10.31, I² = 0%, P = 0.009) were associated with increased mortality. These findings highlight the aggressive clinical course of COVID‐19 in HT recipients.

A propensity score-matched analysis of mortality in solid organ transplant patients with COVID-19 compared to non-solid organ transplant patients

In the context of COVID-19 pandemic, we aimed to analyze the epidemiology, clinical characteristics, risk factors for mortality and impact of COVID-19 on outcomes of solid organ transplant (SOT) recipients compared to a cohort of non transplant patients, evaluating if transplantation could be considered a risk factor for mortality. From March to May 2020, 261 hospitalized patients with COVID-19 pneumonia were evaluated, including 41 SOT recipients. Of these, thirty-two were kidney recipients, 4 liver, 3 heart and 2 combined kidney-liver transplants. Median time from transplantation to COVID-19 diagnosis was 6 years. Thirteen SOT recipients (32%) required Intensive Care Unit (ICU) admission and 5 patients died (12%). Using a propensity score match analysis, we found no significant differences between SOT recipients and non-transplant patients. Older age (OR 1.142; 95% [CI 1.08–1.197]) higher levels of C-reactive protein (OR 3.068; 95% [CI 1.22–7.71]) and levels of serum creatinine on admission (OR 3.048 95% [CI 1.22–7.57]) were associated with higher mortality. The clinical outcomes of SARS-CoV-2 infection in our cohort of SOT recipients appear to be similar to that observed in the non-transplant population. Older age, higher levels of C-reactive protein and serum creatinine were associated with higher mortality, whereas SOT was not associated with worse outcomes.

Clinical implications of SARS-CoV-2 cycle threshold values in solid organ transplant recipients

Detection of SARS-CoV-2 viral RNA by RT-PCR assays is the primary diagnostic test for COVID-19. Cycle threshold (C_T ) values generated by some of these assays provide inversely proportional proxy measurements of viral load. The clinical implications of C_T values are incompletely characterized, particularly in solid organ transplant (SOT) recipients. We conducted a retrospective chart review of 25 adult SOT recipients admitted to the Yale New Haven Health System between March 1 and May 15, 2020, analyzing 50 test results to investigate the clinical implications of SARS-CoV-2 C_T values in this population. Initial C_T values from upper respiratory tract samples were significantly higher in patients on tacrolimus, but were not associated with admission severity nor highest clinical acuity. Viral RNA was detected up to 38 days from symptom onset with a gradual increase in C_T values over time. In five patients with serial testing, C_T values <35.0 were detected >21 days after symptom onset in 4/5 and ≥27 days in 2/5, demonstrating prolonged RNA detection. These data describe SARS-CoV-2 viral dynamics in SOT patients and suggest that C_T values may not be useful to predict COVID-19 severity in SOT patients. SARS-CoV-2 C_T values may be more useful in informing infection prevention measures.

Impact of COVID-19 in solid organ transplant recipients

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exploded onto the world stage in early 2020. The impact on solid organ transplantation (SOT) has been profound affecting potential donors, candidates, and recipients. Importantly, decreased donations and the pressure of limited resources placed on health care by the pandemic also disrupted transplant systems. We address the impact of COVID-19 on organ transplantation globally and review current understanding of the epidemiology, outcomes, diagnosis, and treatment of COVID-19 in SOT recipients.

COVID-19 in immunocompromised patients: A systematic review of cancer, hematopoietic cell and solid organ transplant patients

BACKGROUND

The clinical impact of severe coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in immunocompromised patients has not been systematically evaluated.

METHODS

We reviewed current literature reporting on COVID-19 in cancer (CA), hematopoietic cell (HCT), and solid organ transplant (SOT) patients and compared their clinical data and outcomes to the general population. For adult CA, HCT and SOT patients, an extensive search strategy retrieved all articles published until July 20, 2020 by combining the terms coronavirus, coronavirus infection, COVID-19, and SARS-CoV-2 in PubMed, Cochrane, and Web of Science, and following the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. For the pediatric CA cohort, a global COVID-19 registry was used. For the general population cohort, a large meta-analysis was used to compare pooled prevalence estimates, and two large meta-analyses were utilized to serve as pooled comparators for hospitalized COVID-19 patients.

FINDINGS

Compared to the general population, adult CA and SOT patients with COVID-19 had higher comorbidities, greater levels of inflammatory markers at diagnosis, and higher rates of intensive care and hospital mortality. Pediatric CA patients and HCT patients with COVID-19 tended to have clinical presentations and outcomes similar to the general population.

INTERPRETATION

To our knowledge, this is the first systematic review evaluating COVID-19 phenotype and outcomes in immunocompromised patients and comparing them to the general population, which shows that hospital outcomes appear to be worse in adult CA and SOT patients, potentially due to their higher co-morbidity burden.

FUNDING

None.

COVID-19 in hospitalized liver transplant recipients: An early systematic review and meta-analysis

Adverse clinical outcomes related to SARS‐CoV‐2 infection among liver transplant (LTx) recipients remain undefined. We performed a meta‐analysis to determine the pooled prevalence of outcomes among hospitalized LTx recipients with COVID‐19. A database search of literature published between December 1, 2019, and November 20, 2020, was performed per PRISMA guidelines. Twelve studies comprising 517 hospitalized LTx recipients with COVID‐19 were analyzed. Common presenting symptoms were fever (71%), cough (62%), dyspnea (48%), and diarrhea (28%). Approximately 77% (95% CI, 61%‐93%) of LTx recipients had a history of liver cirrhosis. The most prevalent comorbidities were hypertension (55%), diabetes (45%), and cardiac disease (21%). In‐hospital mortality was 20% (95% CI, 13%‐28%) and rose to 41% (95% CI, 19%‐63%) (P < 0.00) with ICU admission. Additional subgroup analysis demonstrated a higher mortality risk in the elderly (>60‐65 years) (OR 4.26; 95% CI, 2.14‐8.49). There was no correlation in respect to sex or time since transplant. In summary, LTx recipients with COVID‐19 had a high prevalence of dyspnea and gastrointestinal symptoms. In‐hospital mortality was comparable to non‐transplant populations with similar comorbidities but appeared to be less than what is reported elsewhere for cirrhotic patients (26%‐40%). Importantly, the observed high case fatality in the elderly could be due to age‐associated comorbidities.

COVID-19 and Renal Diseases: An Update

BACKGROUND

It becomes increasingly evident that the SARS-CoV-2 infection is not limited to the respiratory system. In addition to being a target of the virus, the kidney also seems to have a substantial influence on the outcomes of the disease.

METHODS

Data was obtained by a comprehensive and non-systematic search in the PubMed, Cochrane, Scopus and SciELO databases, using mainly the terms "SARS-CoV-2", "COVID-19", "chronic kidney disease", "renal transplantation", acute kidney injury" and "renal dysfunction" Discussion: The membrane-bound angiotensin-converting enzyme 2 is the receptor for SARS-CoV- -2, and this interaction may lead to an imbalance of the Renin-Angiotensin System (RAS), associated with worse clinical presentations of COVID-19, including acute pulmonary injury, hyperinflammatory state and hematological alterations. In the framework of renal diseases, the development of acute kidney injury is associated mostly with immune alterations and direct cytopathic lesions by the virus, leading to higher mortality. As for chronic kidney disease, the patients at a non-terminal stage have a worse prognosis, while the hemodialysis patients appear to have mild courses of COVID-19, probably due to lower chances of being affected by the cytokine storm. Furthermore, the current scenario is unfavorable to kidney donation and transplantation. The relationship between COVID-19 and immunosuppression in kidney transplantation recipients has been greatly discussed to determine whether it increases mortality and how it interacts with immunosuppressive medications.

CONCLUSION

The kidney and the RAS exert fundamental roles in the SARS-CoV-2 infection, and more research is required to have a complete understanding of the repercussions caused by COVID-19 in renal diseases.