COVID-19 in Kidney Transplantation: Epidemiology, Management Considerations, and the Impact on Kidney Transplant Practice

A Scoping Review of the Impact of COVID-19 on Kidney Transplant Patients in the United States

SARS-CoV-2, responsible for the COVID-19 pandemic, is a highly infectious virus that quickly became and continues to be a public health emergency, given the severe international implications. Immunocompromised patients, such as those undergoing kidney transplantation, are at an increased risk for severe illness from COVID-19 and require hospitalization for more aggressive treatment to ensure survival. COVID-19 has been infecting kidney transplant recipients (KTRs), affecting their treatment protocols, and threatening their survival. The objective of this scoping review was to summarize the published literature regarding the impact of COVID-19 on KTRs in the United States in terms of prevention, various treatment protocols, COVID-19 vaccination, and risk factors. The databases such as PubMed, MEDLINE/Ebsco, and Embase were used to search for peer-reviewed literature. The search was restricted to articles that were published on KTRs in the United States from January 1, 2019, to March 2022. The initial search yielded 1,023 articles after removing duplicates, leading to a final selection of 16 articles after screening with inclusion and exclusion criteria. Four domains emerged from the review: (1) impacts of COVID-19 on performing kidney transplants, (2) impacts of COVID-19 vaccinations on KTRs, (3) outcomes of treatment regiments for KTRs with COVID-19, and (4) risk factors associated with an increased mortality rate of COVID-19 in KTRs. Waitlisted patients for kidney transplants had a higher risk of mortality compared to nontransplant patients. COVID-19 vaccinations in KTRs are found to be safe, and the immune response can be improved by placing patients on a low dose of mycophenolate before vaccination. Withdrawal of immunosuppressants showed a mortality rate of 20% without increasing the rate of acute kidney injury (AKI). There is evidence to support that kidney transplantation with the accompanying immunosuppressant regimen can provide KTRs with better COVID-19 infection outcomes compared to waitlisted patients. Hospitalization, graft dysfunction, AKI, and respiratory failure were the most common risk factors that increased the risk of mortality in COVID-19-positive KTRs. Withdrawing KTRs from immunosuppressive drugs increased the mortality rate. Further studies are needed to investigate the effects of specific drugs and dosages on the severity and mortality rate of COVID-19 in KTRs.

In Silico Prediction of Hub Genes Involved in Diabetic Kidney and COVID-19 Related Disease by Differential Gene Expression and Interactome Analysis

Diabetic kidney disease (DKD) is a frequently chronic kidney pathology derived from diabetes comorbidity. This condition has irreversible damage and its risk factor increases with SARS-CoV-2 infection. The prognostic outcome for diabetic patients with COVID-19 is dismal, even with intensive medical treatment. However, there is still scarce information on critical genes involved in the pathophysiological impact of COVID-19 on DKD. Herein, we characterize differential expression gene (DEG) profiles and determine hub genes undergoing transcriptional reprogramming in both disease conditions. Out of 995 DEGs, we identified 42 shared with COVID-19 pathways. Enrichment analysis elucidated that they are significantly induced with implications for immune and inflammatory responses. By performing a protein-protein interaction (PPI) network and applying topological methods, we determine the following five hub genes: STAT1, IRF7, ISG15, MX1 and OAS1. Then, by network deconvolution, we determine their co-expressed gene modules. Moreover, we validate the conservancy of their upregulation using the Coronascape database (DB). Finally, tissue-specific regulation of the five predictive hub genes indicates that OAS1 and MX1 expression levels are lower in healthy kidney tissue. Altogether, our results suggest that these genes could play an essential role in developing severe outcomes of COVID-19 in DKD patients.

Mortalidad secundaria a SARS-CoV-2 en pacientes con trasplante renal de un centro del nordeste colombiano

Objetivo Describir la tasa de mortalidad de infección por coronavirus de tipo 2 causante del síndrome respiratorio agudo severo (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2, en inglés) y los factores de riesgo asociados a la severidad de la enfermedad en pacientes con trasplante renal de un centro del nordeste colombiano.

Materiales y Métodos Estudio descriptivo de una cohorte de pacientes en seguimiento postrasplante renal, en el que se hizo una búsqueda retrospectiva de los que presentaron infección por SARS-CoV-2 entre marzo del 2020 y mayo del 2021. Para el análisis, se incluyeron los pacientes con infección confirmada mediante pruebas de reacción en cadena de la polimerasa (polymerase chain reaction, PCR, en inglés), de antígenos, o de anticuerpos. Se realizó un análisis descriptivo de las variables sociodemográficas y clínicas, y un análisis bivariado de los posibles factores asociados con el riesgo de mortalidad.

Resultados Con un total de 307 individuos en seguimiento, se encontró una prevalencia del 14,3% (n = 44) de infección por enfermedad por coronavirus 2019 (coronavirus disease 2019, COVID-19, en inglés). La media de edad fue de 56 años, con predominio del género masculino. El esquema de inmunosupresión más frecuente fue micofenolato–tacrolimus–prednisona. Entre los pacientes infectados, la mortalidad fue del 34,1% (15/44), lo que representa el 4,8% de toda la población a estudio. Maás de la mitad de los pacientes requirieron hemodiálisis, y en el 86,7% fue necesario hacer ajustes en el esquema de inmunosupresión.

Conclusión La prevalencia de infección por SARS-CoV-2 en nuestro grupo de trasplantes fue similar a la reportada por otros grupos de trasplante del país, y mayor a la de la población no trasplantada. El valor de creatinina previo a la infección, la edad y las comorbilidades se asociaron con un mayor riesgo de mortalidad.

The impact of COVID-19 on organ donation and transplantation in the UK: lessons learned from the first year of the pandemic

The COVID-19 pandemic had a major impact on UK deceased organ donation and transplantation activity. We used national audit data from NHS Blood and Transplant to explore in detail the effects of the pandemic in comparison with 12 months pre-pandemic, and to consider the impact of the mitigating strategies and challenges placed on ICU by 'waves' of patients with COVID-19. Between 11 March 2020 and 10 March 2021, referrals to NHS Blood and Transplant of potential organ donors were initially inversely related to the number of people with COVID-19 undergoing mechanical ventilation in intensive care (incident rate ratio (95%CI) per 1000 patients 0.93 (0.88-0.99), p = 0.018), although this pattern reversed during the second wave (additional incident rate ratio (95%CI) 1.12 (1.05-1.19), p < 0.001). Adjusted numbers of donors (incident rate ratio (95%CI) 0.71 (0.61-0.81), p < 0.001) and organs retrieved (incident rate ratio (95%CI) 0.89 (0.82-0.97), p = 0.007) were inversely dependent on COVID-19 workload, though weekly numbers of transplants were unrelated (incident rate ratio (95%CI) 0.95 (0.86-1.04), p = 0.235). Non-COVID-19 mortality fell from 15,007 to 14,087 during the first wave (rate ratio (95%CI) 0.94 (0.92-0.96), p < 0.001) but climbed from 18,907 to 19,372 during the second wave (rate ratio (95%CI) 1.02 (1.00-1.05), p = 0.018). There were fewer in-hospital deaths from cardiac arrest and intracranial catastrophes throughout (rate ratio (95%CI) 0.83 (0.81-0.86), p < 0.001 and rate ratio (95%CI) 0.88 (0.85-0.91), p < 0.001, respectively). There were overall fewer eligible donors (n = 4282) when compared with pre-pandemic levels (n = 6038); OR (95%CI) 0.58 (0.51-0.66), p < 0.001. The total number of donations during the year fell from 1620 to 1140 (rate ratio (95%CI) 0.70 (0.65-0.76), p < 0.001), but the proportion of eligible donors who proceeded to donation (27%) was unchanged (OR (95%CI) 0.99 (0.91-1.08), p = 0.821). The reduction in donations and transplantation during the pandemic was multifactorial, but these data highlight the impact in the UK of a fall in eligible donors and an inverse relationship of referrals to COVID-19 workload. Despite the challenges faced, the foundations underpinning the UK deceased organ donation programme remained strong.

A Comprehensive Comparison of Clinical Presentation and Outcomes of Kidney Transplant Recipients with COVID-19 during Wave 1 versus Wave 2 at a Tertiary Care Center, India

Data comparing the clinical spectrum of COVID-19 in kidney transplant recipients (KTRs) during the first and second waves of the pandemic in India is limited. Our single-center retrospective study compared the clinical profile, mortality, and associated risk factors in KTRs with COVID-19 during the 1st wave (1^st February 2020 to 31^st January 2021) and the second wave (1^st March-31^st August 2021). 156 KTRs with PCR confirmed SARS-CoV-2 infection treated at a tertiary care hospital in New Delhi during the 1st and the second waves were analyzed. The demographics and baseline transplant characteristics of the patients diagnosed during both waves were comparable. Patients in the second wave reported less frequent hospitalization, though the intensive care unit (ICU) and ventilator requirements were similar. Strategies to modify immunosuppressants such as discontinuation of antinucleoside drugs with or without change in calcineurin inhibitors and the use of steroids were similar during both waves. Overall patient mortality was 27.5%. The demographics and baseline characteristics of survivors and nonsurvivors were comparable. A higher percentage of nonsurvivors presented with breathing difficulty, low SpO₂, and altered sensorium. Both wave risk factors for mortality included older age, severe disease, ICU/ventilator requirements, acute kidney injury (AKI) needing dialysis, Chest Computerized Tomographic (CT) scan abnormalities, and higher levels of inflammatory markers particularly D-dimer and interleukin-6 levels. Conclusions. KTRs in both COVID-19 waves had similar demographics and baseline characteristics, while fewer patients during the second wave required hospitalization. The D-dimer and IL-6 levels are directly correlated with mortality.

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.

The Tsunami of COVID-19 Infection Among Kidney Transplant Recipients: A Single-Center Study from Iran

BACKGROUND

Although most evidence supports the fact that kidney transplant (KT) recipients are at significant risk of morbidity and mortality, risk factors of accruing COVID-19 in this population have remained poorly defined.

METHODS

All KT recipients who had been transplanted in Sina Hospital and were actively followed between March 1996 and January 2021 were enrolled in a retrospective manner. The demographic characteristics, immunosuppressive treatment before KT, and death were gathered by calling patients with a designed questionnaire.

RESULTS

108 (about 21%) of 523 KT recipients were diagnosed with COVID-19. The mean age of COVID-19 patients was 46.9 ± 13.6, of whom 43% were women. In the multivariate model, body mass index (BMI) ≥ 30 independently increased the risk of COVID-19 incidence with OR 2.00 (95% CI 1.23, 3.26) (P = 0.00), and besides, having diabetes had a marginal association with COVID-19 incidence (OR 1.62 [95% CI 0.98, 2.66]; P = 0.057). The mortality rate of COVID-19 was 15%. In the multivariate model, only pre-transplantation diabetes significantly increased the risk of death by COVID-19 with OR of 3.90 (95% CI 1.00-15.16) (P = 0.04).

CONCLUSION

Given the higher incidence rate in KT recipients with obesity and diabetes and higher mortality rate in KT recipients with diabetes as the cause of ESRD, more attention should be paid to KT recipients with these risk factors.

The Role of HLA Antigens and Steroid Dose on the Course of COVID-19 of Patients After Kidney Transplantation

Background: Kidney transplant recipients appear to be at higher risk for critical COVID-19. Our analysis aimed to identify the possible risk factors for a severe course of the COVID-19 disease and to determine the influence of selected human leukocyte antigens (HLAs) on the course of the disease.

Methods: This is a retrospective, multicenter analysis that included patients that were confirmed to be severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) positive after kidney transplantation (KT). The group of patients was divided into two subgroups according to the course of the infection, as follows: non-hospitalized and hospitalized.

Results: A total of 186 patients (men, 69.4%) with confirmed SARS-CoV-2 positivity were included in the group. The following independent risk factors for the outcome of hospitalization were identified: the age at the time of infection [odds ratio (OR) = 1.19, P < 0.0001], a body mass index (BMI) >29.9 kg/m² (OR = 7.21, P < 0.0001), <7.5-mg prednisone dose/day (OR = 2.29, P = 0.0008), and HLA-DQ2 with a protective nature (OR = 0.05, P = 0.0034).

Conclusions: Higher doses of corticosteroids (>7.5 mg/kg) in standard immunosuppressive regimes and HLA-DQ2 appear to be protective factors in our analysis.

COVID-19 Infection Clinical Profile, Management, Outcome, and Antibody Response in Kidney Transplant Recipients: A Single Centre Experience

INTRODUCTION

Experience of COVID-19 in kidney transplant recipients (KTRs) with clinical presentation, management, factors influencing mortality, and antibody response is limited. Material and Methods. A retrospective data of COVID-19 in KTRs was collected and analyzed. The mortality rate, risk factors, and antibody response were primary objectives, while the clinical presentation, laboratory indicators, and pharmacological management were secondary objectives.

RESULTS

The 67 KTRs with polymerase chain reaction (PCR) confirmed COVID-19 infection reported between 1 May 2020 and 31 December 2020; 61.2% of patients were hospitalized; and 20.9% needed ventilation. The overall mortality was 26.9%, while blood group A had 50% mortality. The treatment options and used were steroids (100%), convalescent plasma (32.8%), ivermectin (58.2%), doxycycline (55.2%), remdesivir (34.3%), tocilizumab (10.4%), antibiotics (61.2%), anti-fungals (26.9%), low molecular weight heparin (45.3%), and oral anti-coagulants (26.9%). Anti-nucleosides (mycophenolate or azathioprine) were discontinued in 76.1% and calcineurin inhibitors (CNI) in 26.9%. Significant mortality (p < 0.001) was observed in patients presenting with SpO2 <94 needing ICU care, ventilation, dialysis/acute kidney injury (AKI), and empirical therapies like convalescent plasma and remdesivir. The age of survivors versus nonsurvivors was not significantly different (p=0.02). The positive blood culture, low serum albumin, high TLC, high blood urea, interleukin-6, and CT severity score ≥15 were statistically significant in nonsurvivors. Overall mortality, mortality of hospitalized patients, and mortality of ventilated patients was 27%, 44%, and 100%, respectively. The median value of SARS-CoV-2 (COVID-19) IgG antibody was 68.60 (IQR, 28.5-94.25) AU/ml in more than 90% of survivors.

CONCLUSION

KTRs with COVID-19, needing ICU care, dialysis and ventilation support had poor outcomes. Recovered patients mounted adequate antibody response.

mTOR-Inhibition and COVID-19 in Kidney Transplant Recipients: Focus on Pulmonary Fibrosis

Kidney transplant recipients are at high risk of developing severe COVID-19 due to the coexistence of several transplant-related comorbidities (e.g., cardiovascular disease, diabetes) and chronic immunosuppression. As a consequence, a large part of SARS-CoV-2 infected patients have been managed with a reduction of immunosuppression. The mTOR-I, together with antimetabolites, have been often discontinued in order to minimize the risk of pulmonary toxicity and to antagonize pharmacological interaction with antiviral/anti-inflammatory drugs. However, at our opinion, this therapeutic strategy, although justified in kidney transplant recipients with severe COVID-19, should be carefully evaluated in asymptomatic/paucisymptomatic patients in order to avoid the onset of acute allograft rejections, to potentially exploit the mTOR-I antiviral properties, to reduce proliferation of conventional T lymphocytes (which could mitigate the cytokine storm) and to preserve Treg growth/activity which could reduce the risk of progression to severe disease. In this review, we discuss the current literature regarding the therapeutic potential of mTOR-Is in kidney transplant recipients with COVID-19 with a focus on pulmonary fibrosis.

Coronavirus Disease (COVID)-19 and Diabetic Kidney Disease

The present review describes COVID-19 severity in diabetes and diabetic kidney disease. We discuss the crucial effect of COVID-19-associated cytokine storm and linked injuries and associated severe mesenchymal activation in tubular epithelial cells, endothelial cells, and macrophages that influence neighboring cell homeostasis, resulting in severe proteinuria and organ fibrosis in diabetes. Altered microRNA expression disrupts cellular homeostasis and the renin-angiotensin-system, targets reno-protective signaling proteins, such as angiotensin-converting enzyme 2 (ACE2) and MAS1 receptor (MAS), and facilitates viral entry and replication in kidney cells. COVID-19-associated endotheliopathy that interacts with other cell types, such as neutrophils, platelets, and macrophages, is one factor that accelerates prethrombotic reactions and thrombus formation, resulting in organ failures in diabetes. Apart from targeting vital signaling through ACE2 and MAS, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections are also associated with higher profibrotic dipeptidyl transferase-4 (DPP-4)-mediated mechanisms and suppression of AMP-activated protein kinase (AMPK) activation in kidney cells. Lowered DPP-4 levels and restoration of AMPK levels are organ-protective, suggesting a pathogenic role of DPP-4 and a protective role of AMPK in diabetic COVID-19 patients. In addition to standard care provided to COVID-19 patients, we urgently need novel drug therapies that support the stability and function of both organs and cell types in diabetes.

Estimated impact of novel coronavirus-19 and transplant center inactivity on end-stage renal disease-related patient mortality in the United States

To predict whether the COVID‐19 pandemic and transplant center responses could have resulted in preventable deaths, we analyzed registry information of the US end‐stage renal disease (ESRD) patient population awaiting kidney transplantation. Data were from the Organ Procurement and Transplantation Network (OPTN), the US Centers for Disease Control and Prevention, and the United States Renal Data System. Based on 2019 OPTN reports, annualized reduction in kidney transplantation of 25%–100% could result in excess deaths of wait‐listed (deceased donor) transplant candidates from 84 to 337 and living donor candidate excess deaths from 35 to 141 (total 119–478 potentially preventable deaths of transplant candidates). Changes in transplant activity due to COVID‐19 varied with some centers shutting down while others simply heeded known or suspected pandemic risks. Understanding potential excess mortality for ESRD transplant candidates when circumstances compel curtailment of transplant activity may inform policy and procedural aspects of organ transplant systems allowing ways to best inform patients and families as to potential risks in shuttering organ transplant activity. Considering that more than 700 000 Americans have ESRD with 100 000 awaiting a kidney transplant, our highest annual estimate of 478 excess total deaths from postponing kidney transplantation seems modest.

Solid Organ Transplantation During COVID-19 Pandemic: An International Web-based Survey on Resources' Allocation

Supplemental Digital Content is available in the text.

Solid organ transplants (SOTs) are life-saving interventions, recently challenged by coronavirus disease 2019 (COVID-19). SOTs require a multistep process, which can be affected by COVID-19 at several phases.