Outcomes of COVID-19 in Patients with Cirrhosis or Liver Transplantation

Spectrum of COVID-19 induced liver injury: A review report

The coronavirus disease 2019 (COVID-19) pandemic has caused changes in the global health system, causing significant setbacks in healthcare systems worldwide. This pandemic has also shown resilience, flexibility, and creativity in reacting to the tragedy. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection targets most of the respiratory tract, resulting in a severe sickness called acute respiratory distress syndrome that may be fatal in some individuals. Although the lung is the primary organ targeted by COVID-19 viruses, the clinical aspect of the disease is varied and ranges from asymptomatic to respiratory failure. However, due to an unorganized immune response and several affected mechanisms, the liver may also experience liver cell injury, ischemic liver dysfunction, and drug-induced liver injury, which can result in respiratory failure because of the immune system's disordered response and other compromised processes that can end in multisystem organ failure. Patients with liver cirrhosis or those who have impaired immune systems may be more likely than other groups to experience worse results from the SARS-CoV-2 infection. We thus intend to examine the pathogenesis, current therapy, and consequences of liver damage concerning COVID-19.

Vaccine Responses in Patients with Liver Cirrhosis: From the Immune System to the Gut Microbiota

Vaccines prevent a significant number of deaths annually. However, certain populations do not respond adequately to vaccination due to impaired immune systems. Cirrhosis, a condition marked by a profound disruption of immunity, impairs the normal immunization process. Critical vaccines for cirrhotic patients, such as the hepatitis A virus (HAV), hepatitis B virus (HBV), influenza, pneumococcal, and coronavirus disease 19 (COVID-19), often elicit suboptimal responses in these individuals. The humoral response, essential for immunization, is less effective in cirrhosis due to a decline in B memory cells and an increase in plasma blasts, which interfere with the creation of a long-lasting response to antigen vaccination. Additionally, some T cell subtypes exhibit reduced activation in cirrhosis. Nonetheless, the persistence of memory T cell activity, while not preventing infections, may help to attenuate the severity of diseases in these patients. Alongside that, the impairment of innate immunity, particularly in dendritic cells (DCs), prevents the normal priming of adaptive immunity, interrupting the immunization process at its onset. Furthermore, cirrhosis disrupts the gut-liver axis balance, causing dysbiosis, reduced production of short-chain fatty acids (SCFAs), increased intestinal permeability, and bacterial translocation. Undermining the physiological activity of the immune system, these alterations could impact the vaccine response. Enhancing the understanding of the molecular and cellular factors contributing to impaired vaccination responses in cirrhotic patients is crucial for improving vaccine efficacy in this population and developing better prevention strategies.

COVID-19, Possible Hepatic Pathways and Alcohol Abuse-What Do We Know up to 2023?

The pandemic period due to coronavirus disease 2019 (COVID-19) revolutionized all possible areas of global health. Significant consequences were also related to diverse extrapulmonary manifestations of this pathology. The liver was found to be a relatively common organ, beyond the respiratory tract, affected by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Multiple studies revealed the essential role of chronic liver disease (CLD) in the general outcome of coronavirus infection. Present concerns in this field are related to the direct hepatic consequences caused by COVID-19 and pre-existing liver disorders as risk factors for the severe course of the infection. Which mechanism has a key role in this phenomenon-previously existing hepatic disorder or acute liver failure due to SARS-CoV-2-is still not fully clarified. Alcoholic liver disease (ALD) constitutes another not fully elucidated context of coronavirus infection. Should the toxic effects of ethanol or already developed liver cirrhosis and its consequences be perceived as a causative or triggering factor of hepatic impairment in COVID-19 patients? In the face of these discrepancies, we decided to summarize the role of the liver in the whole picture of coronavirus infection, paying special attention to ALD and focusing on the pathological pathways related to COVID-19, ethanol toxicity and liver cirrhosis.

Real-Life Experience in the Efficacy and Safety of COVID-19 Vaccination in Patients with Advanced Cirrhosis

COVID-19 infections accelerate liver decompensation and serious liver-related co-morbidities. The aim is to evaluate the safety and impact of COVID vaccines on hepatic disease progression in patients with advanced liver disease and to identify parameters that predict the occurrence of complications. The study involved 70 patients with advanced liver disease who were vaccinated with different COVID vaccines from January 2021 to April 2022. They were evaluated clinically. The laboratory investigation included a complete blood count, liver and kidney function tests, calculation of CTP and MELD scores, plasma levels of ammonia, abdominal ultrasound, and upper GI endoscopy. Twenty patients had experienced complications 64 ± 12 days from the last dose of a vaccination. Twenty patients (28.6%) developed hepatic decompensation and hypothyroidism (n = 11, 15.7%), and five (7.14%) patients developed splanchnic thrombosis. There were no COVID-19 reinfections except for two patients who received Sinopharm and developed vaccine-associated enhanced disease (2.9%). Complications after COVID vaccinations were correlated with ALT (r = 0.279, p = 0.019), serum sodium (r = -0.30, p = 0.005), creatinine (r = 0.303, p = 0.011), liver volume (LV) (r = -0.640, p = 0.000), and MELD score (r = 0.439, p = 0.000). Multivariate logistic regression revealed that LV is the only independent predictor (p = 0.001). LV ≤ 682.3 has a sensitivity of 95.24% and a specificity of 85.71% in predicting complications with an AUC of 0.935, p < 0.001. In conclusion, the hepatic reserve and prognosis in liver cirrhosis should be evaluated prior to COVID vaccinations using the MELD score and liver volume as promising risk stratification criteria. In summary, the research proposes a novel triaging strategy that involves utilizing the MELD score and liver volume as risk stratification parameters of the hepatic reserve and prognosis of advanced liver cirrhosis prior to COVID immunization to determine who should not receive a COVID vaccination.

Consensus document on acute-on-chronic liver failure (ACLF) established by the Mexican Association of Hepatology

Acute-on chronic liver failure (ACLF) has been an intensively debated topic mainly due to the lack of a unified definition and diagnostic criteria. The growing number of publications describing the mechanisms of ACLF development, the progression of the disease, outcomes and treatment has contributed to a better understanding of the disease, however, it has also sparked the debate about this condition. As an attempt to provide medical professionals with a more uniform definition that could be applied to our population, the first Mexican consensus was performed by a panel of experts in the area of hepatology in Mexico. We used the most relevant and impactful publications along with the clinical and research experience of the consensus participants. The consensus was led by 4 coordinators who provided the most relevant bibliography by doing an exhaustive search on the topic. The entire bibliography was made available to the members of the consensus for consultation at any time during the process and six working groups were formed to develop the following sections: 1.- Generalities, definitions, and criteria, 2.- Pathophysiology of cirrhosis, 3.- Genetics in ACLF, 4.- Clinical manifestations, 5.- Liver transplantation in ACLF, 6.- Other treatments.

Catch-up antibody responses and hybrid immunity in mRNA vaccinated patients at risk of severe COVID-19

BACKGROUND

The immunogenicity of repeated vaccination and hybrid immunity in vulnerable patients remains unclear.

METHODS

We studied the impact of iterative Covid-19 mRNA vaccination and hybrid immunity on antibody levels in immunosuppressed subjects. Patients with liver cirrhosis (n = 38), survivors of allogeneic haematopoietic stem cell transplantation (allo-HSCT) (n = 36) and patients with autoimmune liver disease (n = 14) along with healthy controls (n = 20) were monitored for SARS-CoV-2-S1 IgG after their 1st-3rd vaccine doses, 31 of whom became infected with the Omicron variant after the 2nd dose. Ten uninfected allo-HSCT recipients received an additional 4th vaccine dose.

RESULTS

Unexpectedly, immunosuppressed patients achieved antibody levels in parity with controls after the 3rd vaccine dose. In all study cohorts, hybrid immunity (effect of vaccination and natural infection) resulted in approximately 10-fold higher antibody levels than vaccine-induced immunity alone.

CONCLUSIONS

Three doses of the Covid-19 mRNA vaccine entailed high antibody concentrations even in immunocompromised individuals, and hybrid-immunity resulted further augmented levels than vaccination alone. Clinical trial registration: EudraCT 2021-000349-42.

Evaluation of the effects of the pandemic period on cirrhosis patients

Introduction

Cirrhosis is a common liver disease, which is characterized by life-limiting complications. In cirrhosis, liver ACE2 mRNA levels were 34-times upregulated, ACE2 protein 97-times upregulated, and ACE2 receptors increased in 80% of hepatocytes. Increased ACE2 receptor sensitizes hepatocytes to COVID-19.

Aim

To evaluate the applications of cirrhosis patients to the Emergency Department before and after the pandemic.

Material and methods

The study was conducted retrospectively in a single centre on cirrhotic patients who applied to the Emergency Department in a 2-year period. The obtained data were compared with the laboratory values of the patients: the severity of cirrhosis, the reasons for applying to the Emergency Department, hospitalization/discharge status, and pre-pandemic and pandemic period values. The mortality of the patients was recorded.

Results

The biochemical values, CTP score, and complications of cirrhosis patients deteriorated during the pandemic period, which contributed to the increase in mortality and that the CTP score and its complications worsened, which contributed to the increase in mortality. COVID-19 positivity contributes to the progression of the CTP score, but it is not directly associated with mortality.

Conclusions

We think that new treatment protocols should be included in the guidelines to minimize the effects of this type of viral infection on the liver.

A third dose of the BNT162b2 mRNA vaccine sufficiently improves the neutralizing activity against SARS-CoV-2 variants in liver transplant recipients

Introduction

We examined the neutralizing antibody production efficiency of the second and third severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine doses (2^nd- and 3^rd-dose) and neutralizing activity on mutant strains, including, the Ancestral, Beta and Omicron strains using green fluorescent protein-carrying recombinant SARS-CoV-2, in living-donor liver transplantation (LDLT) recipients.

Methods

The patients who were administered vaccines other than Pfizer- BioNTechBNT162b2 and who had coronavirus disease 2019 in this study period were excluded. We enrolled 154 LDLT recipients and 50 healthy controls.

Result

The median time were 21 days (between 1^st and 2^nd vaccination) and 244 days (between 2^nd and 3^rd vaccination). The median neutralizing antibody titer after 2^nd-dose was lower in LDLT recipients than in controls (0.46 vs 1.00, P<0.0001). All controls had SARS-CoV-2 neutralizing antibodies, whereas 39 LDLT recipients (25.3%) had no neutralizing antibodies after 2^nd-dose; age at vaccination, presence of ascites, multiple immunosuppressive treatments, and mycophenolate mofetil treatment were significant risk factors for nonresponder. The neutralizing activities of recipient sera were approximately 3-fold and 5-fold lower than those of control sera against the Ancestral and Beta strains, respectively. The median antibody titer after 3^rd-dose was not significantly different between recipients and controls (1.02 vs 1.22, p=0.0758); only 5% recipients was non-responder. The neutralizing activity after third dose to Omicron strains were enhanced and had no significant difference between two groups.

Conclusion

Only the 2nd-dose was not sufficiently effective in recipients; however, 3rd-dose had sufficient neutralizing activity against the mutant strain and was as effective as that in healthy controls.

SARS-CoV-2 induced liver injury: Incidence, risk factors, impact on COVID-19 severity and prognosis in different population groups

Liver is unlikely the key organ driving mortality in coronavirus disease 2019 (COVID-19) however, liver function tests (LFTs) abnormalities are widely observed mostly in moderate and severe cases. According to this review, the overall prevalence of abnormal LFTs in COVID-19 patients ranges from 2.5% to 96.8% worldwide. The geographical variability in the prevalence of underlying diseases is the determinant for the observed discrepancies between East and West. Multifactorial mechanisms are implicated in COVID-19-induced liver injury. Among them, hypercytokinemia with "bystander hepatitis", cytokine storm syndrome with subsequent oxidative stress and endotheliopathy, hypercoagulable state and immuno-thromboinflammation are the most determinant mechanisms leading to tissue injury. Liver hypoxia may also contribute under specific conditions, while direct hepatocyte injury is an emerging mechanism. Except for initially observed severe acute respiratory distress syndrome corona virus-2 (SARS-CoV-2) tropism for cholangiocytes, more recent cumulative data show SARS-CoV-2 virions within hepatocytes and sinusoidal endothelial cells using electron microscopy (EM). The best evidence for hepatocellular invasion by the virus is the identification of replicating SARS-CoV-2 RNA, S protein RNA and viral nucleocapsid protein within hepatocytes using in-situ hybridization and immunostaining with observed intrahepatic presence of SARS-CoV-2 by EM and by in-situ hybridization. New data mostly derived from imaging findings indicate possible long-term sequelae for the liver months after recovery, suggesting a post-COVID-19 persistent live injury.

COVID-19 and liver injury: Pathophysiology, risk factors, outcome and management in special populations

The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 is an ongoing health concern. In addition to affecting the respiratory system, COVID-19 can potentially damage other systems in the body, leading to extra-pulmonary manifestations. Hepatic manifestations are among the common consequences of COVID-19. Although the precise mechanism of liver injury is still questionable, several mechanisms have been hypothesized, including direct viral effect, cytokine storm, hypoxic-ischemic injury, hypoxia-reperfusion injury, ferroptosis, and hepatotoxic medications. Risk factors of COVID-19-induced liver injury include severe COVID-19 infection, male gender, advanced age, obesity, and underlying diseases. The presentations of liver involvement comprise abnormalities in liver enzymes and radiologic findings, which can be utilized to predict the prognosis. Increased gamma-glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase levels with hypoalbuminemia can indicate severe liver injury and anticipate the need for intensive care units’ hospitalization. In imaging, a lower liver-to-spleen ratio and liver computed tomography attenuation may indicate a more severe illness. Furthermore, chronic liver disease patients are at a higher risk for severe disease and death from COVID-19. Nonalcoholic fatty liver disease had the highest risk of advanced COVID-19 disease and death, followed by metabolic-associated fatty liver disease and cirrhosis. In addition to COVID-19-induced liver injury, the pandemic has also altered the epidemiology and pattern of some hepatic diseases, such as alcoholic liver disease and hepatitis B. Therefore, it warrants special vigilance and awareness by healthcare professionals to screen and treat COVID-19-associated liver injury accordingly.

Outcomes of COVID-19 among patients with liver disease

Coronavirus disease 2019 (COVID-19) is primarily a respiratory disease with multi-organ involvement, including impaired liver function. It has been noticed that a significant proportion of COVID-19 patients have liver dysfunction, especially those with a more severe disease course. The coronavirus causes direct damage to the liver using the angiotensin-converting enzyme 2, a cell-surface receptor for cellular entry, that is expressed in the liver. According to previous research, liver enzyme abnormalities were observed in a considerable proportion of COVID-19 patients, and elevated liver transaminases were found in about 20% of these patients, alkaline phosphatase in 6.1%, and gamma-glutamyl transferase in 21.1%. COVID-19 might trigger a deterioration of liver function in patients with pre-existing chronic liver diseases (CLDs) and also in those without previous liver disorders. The majority of COVID-19 patients who develop liver injury are men, the elderly, and those with a higher body mass index. Compared to the general population, COVID-19 is associated with significant morbidity and mortality in patients with liver disease (cirrhosis and liver transplantation recipients). However, some studies indicate that CLDs have a lesser role in determining patient progression towards higher disease severity.

Pathogenetic Mechanisms of Liver-Associated Injuries, Management, and Current Challenges in COVID-19 Patients

The global outbreak of COVID-19 possesses serious challenges and adverse impacts for patients with progression of chronic liver disease and has become a major threat to public health. COVID-19 patients have a high risk of lung injury and multiorgan dysfunction that remains a major challenge to hepatology. COVID-19 patients and those with liver injury exhibit clinical manifestations, including elevation in ALT, AST, GGT, bilirubin, TNF-α, and IL-6 and reduction in the levels of CD4 and CD8. Liver injury in COVID-19 patients is induced through multiple factors, including a direct attack of SARS-CoV-2 on liver hepatocytes, hypoxia reperfusion dysfunction, cytokine release syndrome, drug-induced hepatotoxicity caused by lopinavir and ritonavir, immune-mediated inflammation, renin-angiotensin system, and coagulopathy. Cellular and molecular mechanisms underlying liver dysfunction are not fully understood in severe COVID-19 attacks. High mortality and the development of chronic liver diseases such as cirrhosis, alcoholic liver disease, autoimmune hepatitis, nonalcoholic fatty liver disease, and hepatocellular carcinoma are also associated with patients with liver damage. COVID-19 patients with preexisting or developing liver disease should be managed. They often need hospitalization and medication, especially in conjunction with liver transplants. In the present review, we highlight the attack of SARS-CoV-2 on liver hepatocytes by exploring the cellular and molecular events underlying the pathophysiological mechanisms in COVID-19 patients with liver injury. We also discuss the development of chronic liver diseases during the progression of SARS-CoV-2 replication. Lastly, we explore management principles in COVID-19 patients with liver injury and liver transplantation.

Living with liver disease in the era of COVID-19-the impact of the epidemic and the threat to high-risk populations

The cardinal symptoms of severe acute respiratory syndrome coronavirus 2 infection as the pandemic began in 2020 were cough, fever, and dyspnea, thus characterizing the virus as a predominantly pulmonary disease. While it is apparent that many patients presenting acutely to the hospital with coronavirus disease 2019 (COVID-19) infection have complaints of respiratory symptoms, other vital organs and systems are also being affected. In fact, almost half of COVID-19 hospitalized patients were found to have evidence of some degree of liver injury. Incidence and severity of liver injury in patients with underlying liver disease were even greater. According to the Centers of Disease Control and Prevention, from August 1, 2020 to May 31, 2022 there have been a total of 4745738 COVID-19 hospital admissions. Considering the gravity of the COVID-19 pandemic and the incidence of liver injury in COVID-19 patients, it is imperative that we as clinicians understand the effects of the virus on the liver and conversely, the effect of underlying hepatobiliary conditions on the severity of the viral course itself. In this article, we review the spectrum of novel studies regarding COVID-19 induced liver injury, compiling data on the effects of the virus in various age and high-risk groups, especially those with preexisting liver disease, in order to obtain a comprehensive understanding of this disease process. We also provide an update of the impact of the new Omicron variant and the changing nature of COVID-19 pathogenesis.

Current management of liver diseases and the role of multidisciplinary approach

Liver is an organ having extremely diversified functions, ranging from metabolic and synthetic to detoxification of harmful chemicals. The multifunctionality of the liver in principle requires the multidisciplinary and pluralistic interventions for its management. Several studies have investigated liver function, dysfunction and clinic. This editorial work discusses new ideas, challenges and perspectives of current research regarding multidisciplinary and pluralistic management of liver diseases. In one hand the discussions have carried out on the involvement of extracellular vesicles, Na⁺/H⁺ exchangers, severe acute respiratory syndrome coronavirus 2 and Epstein–Barr virus infections, Drug-induced liver injury, sepsis, pregnancy, and food supplements in hepatic disorders. In the other hand this study has discussed hepatocellular carcinoma algorithms and new biochemical and imaging experiments pertaining to liver diseases. Relevant articles with an impact index value "> 0" from reference citation analysis, which is an open multidisciplinary citation analysis database based on artificial intelligence technology, have served for the study’s argumentation. This work may be a useful tool for the clinical practice and research in managing and investigating liver disorders.

Ferroptosis in COVID-19-related liver injury: A potential mechanism and therapeutic target

The outbreak and worldwide spread of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been a threat to global public health. SARS-CoV-2 infection not only impacts the respiratory system but also causes hepatic injury. Ferroptosis, a distinct iron-dependent form of non-apoptotic cell death, has been investigated in various pathological conditions, such as cancer, ischemia/reperfusion injury, and liver diseases. However, whether ferroptosis takes part in the pathophysiological process of COVID-19-related liver injury has not been evaluated yet. This review highlights the pathological changes in COVID-19-related liver injury and presents ferroptosis as a potential mechanism in the pathological process. Ferroptosis, as a therapeutic target for COVID-19-related liver injury, is also discussed. Discoveries in these areas will improve our understanding of strategies to prevent and treat hepatic injuries caused by COVID-19.

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

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

Impaired SARS-CoV-2-specific T cell reactivity in patients with cirrhosis following mRNA COVID-19 vaccination

Background & Aims

Cirrhosis entails elevated risk of COVID-19-associated mortality. This study determined T cell-mediated and antibody reactivity against the spike 1 (S1) protein of SARS-CoV-2 among 48 patients with cirrhosis and 39 healthy controls after mRNA COVID-19 vaccination.

Methods

SARS-CoV-2-specific T-cell reactivity was measured by induced level of T cell-derived interferon-γ (IFN-γ) in blood cells stimulated ex vivo with multimeric peptides spanning the N-terminal portion of S1. S1-induced IFN-γ was quantified before and after the 1^st and 2^nd vaccination (BNT162b2, Pfizer-BioNTech or mRNA-1273, Moderna) alongside serum IgG against the receptor-binding domain (RBD) within S1 (anti-RBD-S1 IgG).

Results

T-cell reactivity against S1 was reduced in patients with cirrhosis after the 1^st (p <0.001 vs. controls) and 2^nd (p <0.001) vaccination. Sixty-eight percent of patients lacked detectable S1-specific T-cell reactivity after the 1^st vaccination vs. 19% in controls (odds ratio 0.11, 95% CI 0.03-0.48, p = 0.003) and 36% remained devoid of reactivity after the 2^nd vaccination vs. 6% in controls (odds ratio 0.12, 95% CI 0.03-0.59, p = 0.009). T-cell reactivity in cirrhosis remained significantly impaired after correction for potential confounders in multivariable analysis. Advanced cirrhosis (Child-Pugh class B) was associated with absent or lower T-cell responses (p <0.05 vs. Child-Pugh class A). The deficiency of T-cell reactivity was paralleled by lower levels of anti-RBD-S1 IgG after the 1^st (p <0.001 vs. controls) and 2^nd (p <0.05) vaccination.

Conclusions

Patients with cirrhosis show deficient T-cell reactivity against SARS-CoV-2 antigens along with diminished levels of anti-RBD-S1 IgG after dual COVID-19 vaccination, highlighting the need for vigilance and additional preventative measures.

Clinical trial registration

EudraCT 2021-000349-42

Lay summary

T cells are a pivotal component in the defence against viruses. We show that patients with cirrhosis have impaired SARS-CoV-2-specific T-cell responses and lower antibody levels after mRNA vaccination against COVID-19 compared with healthy controls. Patients with more advanced liver disease exhibited particularly inferior vaccine responses. These results call for additional preventative measures in these patients.

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After COVID-19 vaccination, patients with cirrhosis had impaired T-cell and antibody responses.

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Child-Pugh class B cirrhosis was associated with poorer immune responses than class A.

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Multivariate analyses excluded potential confounding variables.

COVID-19 and liver dysfunction: Epidemiology, association and potential mechanisms

Currently, there have been more than one hundred million confirmed cases of coronavirus disease 2019 (COVID-19), with two million deaths worldwide. This has caused a huge medical burden. Severe COVID-19 patients can experience multi-organ damage, including cardiac injury, kidney injury, and liver injury. About 2.0%-4.9% of COVID-19 cases involve patients with preexisting liver diseases. Additionally, preexisting liver diseases were reported and associated with severity (odds ratio (OR) or risk ratio (RR) = 1.48-1.70) and mortality (OR or RR = 1.08-2.65) among COVID-19 patients. Furthermore, the prevalence of liver injury was 16%-29% in COVID-19 patients. Higher prevalence of liver injury may worsen prognosis in patients (severity: OR or RR = 1.9-2.6; mortality: OR or RR = 1.1-4.0). The mechanisms of this association between liver injury and severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection are complex, including direct cholangiocyte damage induced by SARS-COV-2, cytokine storm, and drug-induced liver injury. In particular, drug-induced liver injury may be the most important reason. This review discusses the epidemiology of COVID-19 and liver dysfunction as well as potential mechanisms underlying the association between COVID-19 and liver dysfunction or other preexisting liver diseases. However, the association between preexisting liver diseases and COVID-19 prognosis and potential mechanisms underlying these associations require further prospective studies.

Sivaramakrishnan V, Bhangui P, Mohanka R, Asthana S, Rohatgi S. Liver Transplant Society of India Guidelines for Liver Transplant During COVID-19 times

Coronavirus disease-2019 (COVID-19) pandemic has affected liver transplantation in many ways. There is risk of infection to the transplant recipients; and COVID-19 is associated with significant risk of mortality in patients on wait list. The Liver Transplant Society of India (LTSI) has prepared guidelines regarding selection of adult and pediatric patients for liver transplantation, transplant for acute liver failure, use of deceased donor organs, transplant techniques and minimally invasive donor hepatectomy, pre- and postsurgery testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related coronavirus disease 2019 in donors and recipients, role of COVID-19 antibody testing, shifting of recipients from COVID-19 to non-COVID-19 areas after recovery, isolation policy of team members exposed to COVID-19 patients, drug therapy of proven or suspected COVID-19 infection early posttransplant, care of SARS-CoV-2 positive donors and recipients and a separate COVID-19 consent for surgery.

Impact of COVID-19 on liver transplant recipients-A systematic review and meta-analysis

BACKGROUND

Immunosuppression and comorbidities increase the risk of severe coronavirus disease-2019 (COVID-19) in solid organ transplant (SOT) recipients. The outcomes of COVID-19 in liver transplant (LT) recipients remain unclear. We aimed to analyse the outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in LT recipients.

METHODS

The electronic databases were searched for articles published from 1 December 2019 to 20 May 2021 with MeSH terms COVID-19, SARS-CoV-2, and liver transplantation. Studies reporting outcomes in more than 10 LT recipients were included for analysis. LT vs non-LT patients with COVID-19 infection were compared for all-cause mortality, which was the primary outcome studied. We also evaluated the relation between the timing of COVID-19 infection post-LT (< one year vs > one year) and mortality.

FINDINGS

Eighteen articles reporting 1,522 COVID-19 infected LT recipients were included for the systematic review. The mean age (standard deviation [SD]) was 60·38 (5·24) years, and 68·5% were men. The mean time (SD) to COVID-19 infection was 5·72 (1·75) years. Based on 17 studies (I2 = 7·34) among 1,481 LT recipients, the cumulative incidence of mortality was 17·4% (95% confidence interval [CI], 15·4-19·6). Mortality was comparable between LT (n = 610) and non-LT (n = 239,704) patients, based on four studies (odds ratio [OR], 0·8 [0·6-1·08]; P = 0·14). Additionally, there was no significant difference in mortality between those infected within one year vs after one year of LT (OR, 1·5 [0·63-3·56]; P = 0·35). The cumulative incidence of graft dysfunction was 2·3% (1·3-4·1). Nearly 23% (20·71-25) of the LT patients developed severe COVID-19 infection. Before infection, 71% and 49% of patients were on tacrolimus and mycophenolate mofetil, respectively. Immunosuppression was modified in 55·9% (38·1-72·2) patients after COVID-19 infection.

INTERPRETATION

LT and non-LT patients with COVID-19 have a similar risk of adverse outcomes.