慢性基础肝病对新型冠状病毒肺炎患者结局的影响

目的 目前,由严重急性呼吸综合征冠状病毒-2(SARS-Co V-2)感染导致的新型冠状病毒肺炎(COVID-19)仍在全球肆虐,成为国际关注的卫生公共事件。报道显示约2%～11%SARS-Co V-2感染患者患有慢性肝病基础,可出现不同程度的肝脏生化学异常。然而,SARS-Co V-2感染是否加重慢性肝病人群肝功能恶化导致慢加急性肝衰竭或急性肝功能失代偿等事件,仍有待于深入研究。本综述讨论了不同慢性肝病人群感染COVID-19的临床病程和预后情况,为临床治疗提供参考。     

COVID-19 and liver injury: An ongoing challenge

The new coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified in December 2019, in Wuhan, China. The virus was rapidly spread worldwide, causing coronavirus disease 2019 (COVID-19) pandemic. Although COVID-19 is presented, usually, with typical respiratory symptoms (i.e., dyspnea, cough) and fever, extrapulmonary manifestations are also encountered. Liver injury is a common feature in patients with COVID-19 and ranges from mild and temporary elevation of liver enzymes to severe liver injury and, even, acute liver failure. The pathogenesis of liver damage is not clearly defined; multiple mechanisms contribute to liver disorder, including direct cytopathic viral effect, cytokine storm and immune-mediated hepatitis, hypoxic injury, and drug-induced liver toxicity. Patients with underlying chronic liver disease (i.e., cirrhosis, non-alcoholic fatty liver disease, alcohol-related liver disease, hepatocellular carcinoma, etc.) may have greater risk to develop both severe COVID-19 and further liver deterioration, and, as a consequence, certain issues should be considered during disease management. The aim of this review is to present the prevalence, clinical manifestation and pathophysiological mechanisms of liver injury in patients with SARS-CoV-2 infection. Moreover, we overview the association between chronic liver disease and SARS-CoV-2 infection and we briefly discuss the management of liver injury during COVID-19.     

SARS-CoV-2 Infection and Liver Disease: A Review of Pathogenesis and Outcomes

The impact of the coronavirus disease 2019 (COVID-19) pandemic has been immense, and it continues to have lasting repercussions. While the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus primarily infects the respiratory system, other organ systems are affected, including the liver. Scientific knowledge on the role of SARS-CoV-2 infection and liver injury has evolved rapidly, with recent data suggesting specific hepatotropism of SARS-CoV-2. Moreover, additional concerns have been raised in regard to long-term liver damage, related to emerging cases of post-COVID-19 cholangiopathy and chronic cholestasis. Great effort has also been focused on studying how specific subpopulations with chronic medical conditions might be disproportionately impacted by COVID-19. One such population includes individuals with chronic liver disease (CLD) and cirrhosis, with an expanding body of research indicating these patients being particularly susceptible to adverse outcomes. In this review, we provide an updated summary on the current pathogenesis and mechanism of liver injury in the setting of SARS-CoV-2 infection, the association between health outcomes and SARS-CoV-2 infection in patients with CLD, and the unique consequences of the COVID-19 pandemic on the routine care of patients with CLD.     

COVID-19 and the liver: What do we know so far?

The coronavirus disease 2019(COVID-19) pandemic has caused unprecedented pressure on public health and healthcare. The pandemic surge and resultant lockdown have affected the standard-of-care of many medical conditions and diseases. The initial uncertainty and fear of cross transmission of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) have changed the routine management of patients with pre-existing liver diseases, hepatocellular carcinoma, and patients either listed for or received a liver transplant. COVID-19 is best described as a multisystem disease caused by SARS-CoV-2, and it can cause acute liver injury or decompensation of the pre-existing liver disease. There has been considerable research on the pathophysiology, infection transmission, and treatment of COVID-19 in the last few months. The pathogenesis of liver involvement in COVID-19 includes viral cytotoxicity, the secondary effect of immune dysregulation, hypoxia resulting from respiratory failure, ischemic damage caused by vascular endotheliitis, congestion because of right heart failure, or drug-induced liver injury. Patients with chronic liver diseases, cirrhosis, and hepatocellular carcinoma are at high risk for severe COVID-19 and mortality. The phase Ⅲ trials of recently approved vaccines for SARS-CoV-2 did not include enough patients with pre-existing liver diseases and excluded immunocompromised patients or those on immunomodulators. This article reviews the currently published research on the effect of COVID-19 on the liver and the management of patients with pre-existing liver disease, including SARS-CoV-2 vaccines.     

Autoimmune liver diseases and SARS-CoV-2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing coronavirus disease 2019 (COVID-19), can trigger autoimmunity in genetically predisposed individuals through hyperstimulation of immune response and molecular mimicry. Here we summarise the current knowledge about auto-immune liver diseases (AILDs) and SARS-CoV-2, focusing on: (1) The risk of SARS-CoV-2 infection and the course of COVID-19 in patients affected by AILDs; (2) the role of SARS-CoV-2 in inducing liver damage and triggering AILDs; and (3) the ability of vaccines against SARS-CoV-2 to induce autoimmune responses in the liver. Data derived from the literature suggest that patients with AILDs do not carry an increased risk of SARS-Cov-2 infection but may develop a more severe course of COVID-19 if on treatment with steroids or thiopurine. Although SARS-CoV-2 infection can lead to the development of several autoimmune diseases, few reports correlate it to the appearance of de novo manifestation of immune-mediated liver diseases such as autoimmune hepatitis (AIH), primary biliary cholangitis (PBC) or AIH/PBC overlap syndrome. Different case series of an AIH-like syndrome with a good prognosis after SARS-CoV-2 vaccination have been described. Although the causal link between SARS-CoV-2 vaccines and AIH cannot be definitively established, these reports suggest that this association could be more than coincidental.     

Molecular mechanisms implicated in SARS-CoV-2 liver tropism

The coronavirus disease 2019 (COVID-19) pandemic is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Hepatic involvement is common in SARS-CoV-2-infected individuals. It is currently accepted that the direct and indirect hepatic effects of SARS-CoV-2 infection play a significant role in COVID-19. In individuals with pre-existing infectious and non-infectious liver disease, who are at a remarkably higher risk of developing severe COVID-19 and death, this pathology is most medically relevant. This review emphasizes the current pathways regarded as contributing to the gastrointestinal and hepatic ailments linked to COVID-19-infected patients due to an imbalanced interaction among the liver, systemic inflammation, disrupted coagulation, and the lung.     

COVID-19 and the Liver: Lessons Learnt from the EAST and the WEST,A Year Later

Globally, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 virus) has been a major cause for significant morbidity and mortality. Since the start of the pandemic, several hepato-biliary manifestations in coronavirus disease 2019 (COVID-19) have been described and unique considerations raised. The review aims to summarize the pathogenesis and hepato-biliary manifestations in COVID-19 and discuss the similarities, contrasting features and disease-specific management across a range of hepato-biliary diseases from the EAST and the WEST. Published studies and regional society guidelines from the EAST and the WEST were comprehensively reviewed and summarized. A wide range of hepato-biliary manifestations, including the infrequent and chronic manifestation of cholangiopathy, has been observed in COVID-19. The pathogenesis of liver injury is multifactorial and with scant evidence for a direct SARS-CoV-2 infection of the liver. Patients with non-alcoholic fatty liver disease, cirrhosis, and liver cancer are potentially at increased risk for severe COVID-19, and there are unique considerations in chronic hepatitis B or C, hepatocellular carcinoma, and in those immunosuppressed such as autoimmune hepatitis or liver transplant recipients. With the surges in SARS-CoV-2 infection, liver transplant activity has variably been impacted. Preliminarily, SARS-CoV-2 vaccines appear to be safe in those with chronic liver disease and in transplant recipients, while emerging data suggest the need for a third dose in immunosuppressed patients. In conclusion, patients with chronic liver disease, particularly cirrhosis, and liver transplant recipients, are vulnerable to severe COVID-19. Over the past year, several unique considerations have been highlighted across a spectrum of hepato-biliary diseases. Vaccination is strongly recommended for those with chronic liver disease and liver transplant recipients.     

COVID-19 and comorbidities of hepatic diseases in a global perspective

The worldwide outbreak of coronavirus disease 2019 (COVID-19) has challenged the priorities of healthcare system in terms of different clinical management and infection transmission, particularly those related to hepatic-disease comorbidities. Epidemiological data evidenced that COVID-19 patients with altered liver function because of hepatitis infection and cholestasis have an adverse prognosis and experience worse health outcomes. COVID-19-associated liver injury is correlated with various liver diseases following a severe acute respiratory syndrome-coronavirus type 2 (SARS-CoV-2) infection that can progress during the treatment of COVID-19 patients with or without pre-existing liver disease. SARS-CoV-2 can induce liver injury in a number of ways including direct cytopathic effect of the virus on cholangiocytes/hepatocytes, immune-mediated damage, hypoxia, and sepsis. Indeed, immediate cytopathogenic effects of SARS-CoV-2 via its potential target, the angiotensin-converting enzyme-2 receptor, which is highly expressed in hepatocytes and cholangiocytes, renders the liver as an extra-respiratory organ with increased susceptibility to pathological outcomes. But, underlying COVID-19-linked liver disease pathogenesis with abnormal liver function tests (LFTs) is incompletely understood. Hence, we collated COVID-19-associated liver injuries with increased LFTs at the nexus of pre-existing liver diseases and COVID-19, and defining a plausible pathophysiological triad of COVID-19, hepatocellular damage, and liver disease. This review summarizes recent findings of the exacerbating role of COVID-19 in pre-existing liver disease and vice versa as well as international guidelines of clinical care, management, and treatment recommendations for COVID-19 patients with liver disease.     

Liver injury in the era of COVID-19

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has undoubtedly revolutionized the whole globe and given a new point of view on respiratory tract infections. Nevertheless, coronavirus disease 2019 (COVID-19) cannot be perceived as a disease limited only to pneumonia with diverse severity. More and more reports have demonstrated a wide range of possible systemic symptoms, including hepatic complications. Liver injury has been observed in a significant proportion of patients, especially in those with a severe or critical illness. COVID-19 might provoke a deterioration of liver function in patients with already diagnosed chronic liver diseases and without pre-existing liver disorders. The deterioration of liver function worsens the prognosis, increases the risk of a severe course of SARS-CoV-2 infection and prolongs the hospital stay. In general, patients who develop liver dysfunction in COVID-19 are mainly males, elderly people, and those with higher body mass index. The underlying mechanisms for hepatic failure in patients infected with SARS-CoV-2 are still unclear, nevertheless liver damage appears to be directly connected with virus-induced cytopathic effects. A liver injury observed during hospitalization might be simultaneously caused by the use of potentially hepatotoxic drugs, mainly antiviral agents. This minireview focuses on a possible relationship between COVID-19 and the liver, potential molecular mechanisms of liver damage, the characteristics of liver injury and suggested factors predisposing to hepatic manifestations in COVID-19 patients.     

COVID-19 and its effects on the digestive system

Coronavirus disease 2019 (COVID-19) is caused by infection of the coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with typical respiratory symptoms. SARS-CoV-2 invades not only the respiratory system, but also other organs expressing the cell surface receptor angiotensin converting enzyme 2. In particular, the digestive system is a susceptible target of SARS-CoV-2. Gastrointestinal symptoms of COVID-19 include anorexia, nausea, vomiting, diarrhea, abdominal pain, and liver damage. Patients with digestive damage have a greater chance of progressing to severe or critical illness, a poorer prognosis, and a higher risk of death. This paper aims to summarize the digestive system symptoms of COVID-19 and discuss fecal-oral contagion of SARS-CoV-2. It also describes the characteristics of inflammatory bowel disease patients with SARS-CoV-2 infection and discusses precautions for preventing SARS-CoV-2 infection during gastrointestinal endoscopy procedures. Improved attention to digestive system abnormalities and gastrointestinal symptoms of COVID-19 patients may aid health care providers in the process of clinical diagnosis, treatment, and epidemic prevention and control.     

COVID-19 pandemic: Its impact on liver disease and liver transplantation

Severe pulmonary disease caused by the novel coronavirus [severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)], has devastated many countries around the world.It has overwhelmed the medical system.The priorities of many institutions have changed to manage critically ill corona virus infectious disease-2019(COVID-19) patients,which affected the working style of many departments.Hepatologists and transplant surgeons look after a very sensitive patient group.Patients with liver disease need special attention and continuous follow-up.Similarly,transplant candidates also need special care.Healthcare professionals in the field of hepatology face the overwhelming task of taking care of COVID-19 patients with hepatic complications,liver disease or transplant patients who are SARS-CoV-2 positive,and the patients on routine surveillance who do not have COVID-19.This review will evaluate COVID-19 from the perspective of its effect on the liver and its possible effects on patients with liver disease.Furthermore,the level of care for liver transplant recipients during the pandemic will be discussed.     

Liver and COVID-19:From care of patients with liver diseases to liver injury

The global pandemic of coronavirus disease 2019(COVID-19) changed dramatically all priorities on medical society and created several challenges for clinicians caring for patients with liver diseases. We performed a comprehensive review about how COVID-19 can affect the liver, the influence of liver diseases on the risk of developing severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and COVID-19 severity and also some strategies to overcome all the challenges clinicians have to face in the management of patients with liver diseases in a period of time when all the focus turned on COVID-19. We analyze the relationship between COVID-19 and non-alcoholic fatty liver disease, alcoholic liver disease, viral hepatitis, autoimmune liver disease, cirrhosis, hepatocellular carcinoma and liver transplantation, as well as the approach to SARS-CoV-2 vaccination.     

Interaction between hepatitis B virus and SARS-CoV-2 infections

Coronavirus disease 2019(COVID-19)has become a global pandemic and garnered international attention.The causative pathogen of COVID-19 is severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),a novel,highly contagious coronavirus.Numerous studies have reported that liver injury is quite common in patients with COVID-19.Hepatitis B has a worldwide distribution as well as in China.At present,hepatitis B virus(HBV)remains a leading cause of cirrhosis,liver failure,and hepatocellular carcinoma.Because both viruses challenge liver physiology,it raises questions as to how coinfection with HBV and SARS-CoV-2 affect disease progression and mortality.Is there an increased risk of COVID-19 in patients with HBV infection?In this review,we summarize the current reports of SARS-CoV-2 and HBV coinfection and elaborate the interaction of the two diseases.The emphasis was placed on evaluating the impact of HBV infection on disease severity and clinical outcomes in patients with COVID-19 and discussing the potential mechanism behind this effect.     

Acute-on-chronic liver failure in patients with severe acute respiratory syndrome coronavirus 2 infection

The corona virus disease 2019(COVID-19) pandemic caused by the severe acute respiratory syndrome corona virus 2(SARS-CoV-2) has had a significant impact on the lives of millions of people,especially those with other concomitant diseases,such as chronic liver diseases.To date,seven corona viruses have been identified to infect humans.The main site of pathological action of these viruses is lung tissue.However,a substantial number of studies have proven that SARSCoV-2 shows affinity towards severa...     

Liver dysfunction during COVID-19 pandemic: Contributing role of associated factors in disease progression and severity

In December 2019, a new strain of coronavirus was discovered in China, and the World Health Organization declared it a pandemic in March 2020. The majority of people with coronavirus disease 19 (COVID-19) exhibit no or only mild symptoms such as fever, cough, anosmia, and headache. Meanwhile, approximately 15% develop a severe lung infection over the course of 10 d, resulting in respiratory failure, which can lead to multi-organ failure, coagulopathy, and death. Since the beginning of the pandemic, it appears that there has been consideration that pre-existing chronic liver disease may predispose to deprived consequences in conjunction with COVID-19. Furthermore, extensive liver damage has been linked to immune dysfunction and coagulopathy, which leads to a more severe COVID-19 outcome. Besides that, people with COVID-19 frequently have abnormal liver function, with more significant elevations in alanine aminotransferase and aspartate aminotransferase in patients with severe COVID-19 compared to those with mild/moderate disease. This review focuses on the pathogenesis of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in the liver, as well as the use of liver chemistry as a prognostic tool during COVID-19. We also evaluate the findings for viral infection of hepatocytes, and look into the potential mechanisms behind SARS-CoV-2-related liver damage.     

Liver injury in COVID-19: The hepatic aspect of the respiratory syndrome — what we know so far

The 2019 novel coronavirus disease (COVID-19) pandemic due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed a serious threat to global public health. Although primarily, the infection causes lung injury, liver enzyme abnormalities have also been reported to occur during the course of the disease. We conducted an extensive literature review using the PubMed database on articles covering a broad range of issues related to COVID-19 and hepatic injury. The present review summarizes available information on the spectrum of liver involvement, the possible mechanisms and risk factors of liver injury due to SARS-CoV-2 infection, and the prognostic significance of the presence of liver injury. Hopefully, this review will enable clinicians, especially the hepatologists, to understand and manage the liver derangements they may encounter in these patients better and provide guidance for further studies on the liver injury of COVID-19.     

Management of COVID-19 patients with chronic liver diseases and liver transplants

The epidemic of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has increasingly attracted worldwide concern. Liver damage or dysfunction occurred in patients with COVID-19 (mainly characterized by moderately elevated serum aspartate aminotransferase levels). However, it is not yet clear whether the COVID-19-related liver injury is mainly caused by the virus infection, potentially hepatotoxic drugs, or other coexisting conditions. Progression of pre-existing chronic liver disease (CLD) may be the underlying mechanism of liver injury. Although COVID-19 patients with CLD, such as nonalcoholic fatty liver disease, liver cirrhosis, and liver cancer, have been deemed at increased risk for serious illness in many studies, little is known about the impact of CLD on the natural history and outcome of COVID-19 patients. Thereby, based on the latest evidence from case reports and case series, this paper discusses the clinical manifestations, treatment, prognosis, and management of the COVID-19 patients with different CLD. This article also reviews the effect of COVID-19 on liver transplantation patients (LT), hoping to work for future prevention, management, and control measures of COVID-19. However, due to the lack of relevant research, most of them are still limited to the theoretical stage, further study of COVID-19 and CLD needs to be improved in the future.     

Liver-spleen axis dysfunction in COVID-19

Coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an acute infectious disease that spreads mainly through the respiratory route. Besides interstitial pneumonia, a number of other clinical manifestations were noticed in COVID-19 patients. In particular, liver and spleen dysfunctions have been described both as complications of COVID-19 and as potential predisposing factors for severe COVID-19. Liver damage is rather common in COVID-19 patients, and it is most likely multifactorial, caused by the direct insult of SARS-CoV-2 to the liver by the cytokine storm triggered by the virus, by the use of hepatotoxic drugs, and as a consequence of hypoxia. Although generally mild, liver impairment has been found to be associated with a higher rate of intensive care unit admission. A higher mortality rate was reported among chronic liver disease patients. Instead, spleen impairment in patients with COVID-19 has been poorly described. The main anatomical changes are the architectural derangement of the B cell compartment, white pulp atrophy, and reduction or absence of lymphoid follicles, while, from a functional point of view, the IgM memory B cell pool is markedly depleted. The outcome of COVID-19 in asplenic or hyposplenic patients is yet to be defined. In this review, we will summarise the current knowledge regarding the impact of SARS-CoV-2 on the liver and spleen function, as well as the outcome of patients with a pre-existent liver disease or defective spleen function.     

Coronavirus disease 2019 and non-alcoholic fatty liver disease

The coronavirus disease 2019(COVID-19) pandemic may present with a broad range of clinical manifestations, from no or mild symptoms to severe disease. Patients with specific pre-existing comorbidities, such as obesity and type 2 diabetes, are at high risk of coming out with a critical form of COVID-19. Nonalcoholic fatty liver disease(NAFLD) is the most common chronic liver disease, and, because of its frequent association with metabolic alterations including obesity and type 2 diabetes, it has recently been re-named as metabolic-associated fatty liver disease(MAFLD). Several studies and systematic reviews pointed out the increased risk of severe COVID-19 in NAFLD/MAFLD patients. Even though dedicated mechanistic studies are missing, this higher probability may be justified by systemic low-grade chronic inflammation associated with immune dysregulation in NAFLD/MAFLD, which could trigger cytokine storm and hypercoagulable state after severe acute respiratory syndrome coronavirus 2 infection. This review focuses on the predisposing role of NAFLD/MAFLD in favoring severe COVID-19, discussing the available information on specific risk factors, clinical features, outcomes, and pathogenetic mechanisms.     

Clinical perspectives,assessment, and mechanisms of metabolic-associated fatty liver disease in patients with COVID-19

Metabolic diseases are highly prevalent worldwide and have been associated with adverse clinical outcomes, including mortality, in patients developing coronavirus disease (COVID-19). Because of the close relationship between metabolic diseases such as type 2 diabetes mellitus and obesity and the presence of metabolic-associated fatty liver disease (MAFLD), a high number of cases of patients affected by both MAFLD and COVID-19 would be expected, especially in high-risk populations. Some studies have shown an increased risk of adverse clinical outcomes, viral shedding, and deep vein thrombosis, especially in patients with MAFLD- related liver fibrosis. The predisposition to poor outcomes and severe acute respiratory syndrome coronavirus 2 infection in patients with MAFLD could be secondary to mechanisms common to both, including preexisting systemic chronic inflammation, endothelial dysfunction, and involvement of the renin-angiotensin system. Because of the increased risk of adverse outcomes, MAFLD should be screened in all patients admitted for COVID-19. Available computed tomography scans could be of help, assessment of liver fibrosis is also recommended, favoring noninvasive methods to limit the exposure of healthcare workers. Liver involvement in this population ranges from abnormalities in liver chemistry to hepatic steatosis in postmortem biopsies. Finally, preventive measures should be strongly advocated in patients already known to have MAFLD, including the use of telemedicine and vaccination in addition to general measures.