COVID-19 and the liver

COVID-19 and liver disease: mechanistic and clinical perspectives

Our understanding of the hepatic consequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and its resultant coronavirus disease 2019 (COVID-19) has evolved rapidly since the onset of the pandemic. In this Review, we discuss the hepatotropism of SARS-CoV-2, including the differential expression of viral receptors on liver cell types, and we describe the liver histology features present in patients with COVID-19. We also provide an overview of the pattern and relevance of abnormal liver biochemistry during COVID-19 and present the possible underlying direct and indirect mechanisms for liver injury. Furthermore, large international cohorts have been able to characterize the disease course of COVID-19 in patients with pre-existing chronic liver disease. Patients with cirrhosis have particularly high rates of hepatic decompensation and death following SARS-CoV-2 infection and we outline hypotheses to explain these findings, including the possible role of cirrhosis-associated immune dysfunction. This finding contrasts with outcome data in pharmacologically immunosuppressed patients after liver transplantation who seem to have comparatively better outcomes from COVID-19 than those with advanced liver disease. Finally, we discuss the approach to SARS-CoV-2 vaccination in patients with cirrhosis and after liver transplantation and predict how changes in social behaviours and clinical care pathways during the pandemic might lead to increased liver disease incidence and severity.

Impact of cytokine storm and systemic inflammation on liver impairment patients infected by SARS-CoV-2: Prospective therapeutic challenges

Coronavirus disease 2019 (COVID-19) is a devastating worldwide pandemic infection caused by a severe acute respiratory syndrome namely coronavirus 2 (SARS-CoV-2) that is associated with a high spreading and mortality rate. On the date this review was written, SARS-CoV-2 infected about 96 million people and killed about 2 million people. Several arguments disclosed the high mortality of COVID-19 due to acute respiratory distress syndrome or change in the amount of angiotensin-converting enzyme 2 (ACE2) receptor expression or cytokine storm strength production. In a similar pattern, hepatic impairment patients co-infected with SARS-CoV-2 exhibited overexpression of ACE2 receptors and cytokine storm overwhelming, which worsens the hepatic impairment and increases the mortality rate. In this review, the impact of SARS-CoV-2 on hepatic impairment conditions we overviewed. Besides, we focused on the recent studies that indicated cytokine storm as well as ACE2 as the main factors for high COVID-19 spreading and mortality while hinting at the potential therapeutic strategies.

Dynamic Changes in Liver Function Tests and Their Correlation with Illness Severity and Mortality in Patients with COVID-19: A Retrospective Cohort Study

Objective

To describe the longitudinal changes in liver function tests, and their association with illness severity and mortality in patients with COVID-19.

Methods

A retrospective cohort study of 1003 hospitalized patients with COVID-19 was conducted. Longitudinal liver function tests and clinical outcomes were analyzed.

Results

Abnormal liver function parameters were observed, both at admission (ALT 13.2%, AST 8.5%, ALP 2.0%, GGT 7.4%, LDH 37.6%, TBIL 4.0%, DBIL 7.8%, Albumin 10.1%) and peak hospitalization (ALT 29.4%, AST 17.5%, ALP 2.6%, GGT 13.4%, LDH 49.4%, TBIL 10.1%, DBIL 18.0%, Albumin 30.6%) in patients with COVID-19. Compared with non-severe patients, severe patients had markedly higher liver function parameters from baseline to 30 days after hospital admission. Abnormal ALT and LDH at hospital admission and some medications use (Hydroxychloroquine, Lopinavir/Ritonavir, and Traditional Chinese medicines) were associated with peak hospitalization ALT > 5× the upper limit unit of normal (ULN). On multivariate analysis, age >60 years, male, obesity, comorbidity, abnormal LDH and albumin at hospital admission and peak hospitalization were associated with progression to severe COVID-19 (OR > 1; p < 0.05). COX analysis revealed that ALT > 2 ULN (HR=7.0, p=0.011), AST > 2 ULN (HR=34.7, p < 0.001), and TBIL > 2 ULN (HR=54.6, p < 0.001) were associated with a higher mortality.

Conclusion

Dynamic abnormalities of liver function parameters are common in hospitalized patients with COVID-19, and associated with illness severity and mortality.

Bioinformatics and system biology approach to identify the influences of SARS-CoV-2 infections to idiopathic pulmonary fibrosis and chronic obstructive pulmonary disease patients

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), better known as COVID-19, has become a current threat to humanity. The second wave of the SARS-CoV-2 virus has hit many countries, and the confirmed COVID-19 cases are quickly spreading. Therefore, the epidemic is still passing the terrible stage. Having idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) are the risk factors of the COVID-19, but the molecular mechanisms that underlie IPF, COPD, and CVOID-19 are not well understood. Therefore, we implemented transcriptomic analysis to detect common pathways and molecular biomarkers in IPF, COPD, and COVID-19 that help understand the linkage of SARS-CoV-2 to the IPF and COPD patients. Here, three RNA-seq datasets (GSE147507, GSE52463, and GSE57148) from Gene Expression Omnibus (GEO) is employed to detect mutual differentially expressed genes (DEGs) for IPF, and COPD patients with the COVID-19 infection for finding shared pathways and candidate drugs. A total of 65 common DEGs among these three datasets were identified. Various combinatorial statistical methods and bioinformatics tools were used to build the protein–protein interaction (PPI) and then identified Hub genes and essential modules from this PPI network. Moreover, we performed functional analysis under ontologies terms and pathway analysis and found that IPF and COPD have some shared links to the progression of COVID-19 infection. Transcription factors–genes interaction, protein–drug interactions, and DEGs-miRNAs coregulatory network with common DEGs also identified on the datasets. We think that the candidate drugs obtained by this study might be helpful for effective therapeutic in COVID-19.

Epidemiological and Clinical Characteristics of 217 Cases of COVID-19 in Jiangsu Province, China

BACKGROUND COVID-19 has become a worldwide epidemic disease and is a public health crisis. We aim to provide evidence for clinical diagnosis and assessment of severity by analyzing patients' clinical data and early laboratory results and exploring the correlation between laboratory results and clinical classification. MATERIAL AND METHODS We enrolled 283 cases of suspected and diagnosed COVID-19 from 16 hospitals in Jiangsu Province from January to April 2020. The routine laboratory blood examinations, T lymphocyte subsets, and biochemical and coagulation function among different populations were contrasted by t test and chi-square (χ²) test. RESULTS Cough, fever, and dyspnea could be helpful to diagnose COVID-19 infection (P<0.05). Patients who were older or had comorbidities tended to become severe and critical cases. Among all the patients, the most obvious abnormal laboratory results were higher neutrophil count, CRP, total bilirubin, BUN, CRE, APTT, PT, and D-dimer, and lower blood platelet and lymphocyte count. CD3⁺ T cell, CD4⁺ T cell, and CD8⁺ T cell counts gradually decreased with exacerbation of the disease (P<0.05). CONCLUSIONS Cough and fever were the most common symptom. Patients with comorbidities were in more serious condition. The detection of inflammatory indexes, coagulation function, lymphocyte subsets, and renal function can help diagnose and assess the severity of COVID-19.

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.

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.

New Roles for Vitamin D Superagonists: From COVID to Cancer

Vitamin D is a potent steroid hormone that induces widespread changes in gene expression and controls key biological pathways. Here we review pathophysiology of vitamin D with particular reference to COVID-19 and pancreatic cancer. Utility as a therapeutic agent is limited by hypercalcemic effects and attempts to circumvent this problem have used vitamin D superagonists, with increased efficacy and reduced calcemic effect. A further caveat is that vitamin D mediates multiple diverse effects. Some of these (anti-fibrosis) are likely beneficial in patients with COVID-19 and pancreatic cancer, whereas others (reduced immunity), may be beneficial through attenuation of the cytokine storm in patients with advanced COVID-19, but detrimental in pancreatic cancer. Vitamin D superagonists represent an untapped resource for development of effective therapeutic agents. However, to be successful this approach will require agonists with high cell-tissue specificity.

SARS-CoV-2 infection represents a high risk for the elderly: analysis of pathogenesis

As people get older, age-related alterations occur that lead to increased susceptibility to disease. In the current COVID-19 pandemic, older people are particularly susceptible to a SARS-CoV-2 infection developing into severe disease. The objective of this review was to examine the literature regarding factors that may explain the tendency of this population to develop severe COVID-19. Research articles considered in this review were searched for in EMBASE, PubMed, and Web of Science from December 2019 to December 2020. Citations were screened by two independent reviewers. Studies of the immune system in older individuals found alterations in both the adaptive and innate immune systems. The adaptive system is depressed in its functions, and the innate system is in a pro-inflammatory state that can lead to chronic disease. This pro-inflammatory state may be related to a severe course of disease in COVID-19. This review shows that the level of evidence supporting an association between immune alterations in the elderly and susceptibly to severe progression of SARS-CoV-2 infection is generally consistent. Preventive measures such as early antiviral treatment are of key importance for prevention of severe progression of COVID19.

Optimal diagnostic tool for surveillance of oesophageal varices during COVID-19 pandemic

AIM

To study the diagnostic accuracy and utility of triphasic abdominal computed tomography (CT) in the diagnosis and grading of oesophageal varices (OVs) as an alternative to endoscopy during the COVID-19 pandemic.

MATERIALS AND METHODS

A prospective analysis was undertaken of retrospective data from cirrhotic patients who underwent oesophago-gastro-duodenoscopy (OGD) and a triphasic abdominal CT from January to December 2019. Endoscopists and radiologists provided their respective independent assessment of OV grading after being blinded to the clinical details. Performance of CT grading of OVs was compared with the reference standard endoscopic grading using weighted kappa (k). Non-invasive scores such, as aspartate transaminase (AST)-to-platelet ratio index (APRI), Fibrosis-4 (FIB-4) Index, platelet: spleen (PS) ratio were correlated between the two techniques.

RESULTS

OV grading between endoscopists and radiologists showed 81.73% agreement (85 out of 104 patients) in the comparative analysis of 104 cirrhotic patients, of which no varices (57.1%, n=4), small (85.1%, n=23), medium (72.2%%, n=26), and large varices (94.1%, n=32) with a weighted k score of 0.88 (95% confidence interval 0.82-0.94). Overall, the sensitivity of CT in the diagnosis of no, small, medium, and large OVs was 66.6%, 79.3%, 89.6%, and 94.1%, respectively, with an area under the receiver operating curve (AUROC) score of 0.775, 0.887, 0.839, and 0.914. Performance of APRI, FIB-4, and PS ratio correlated well with the severity of OVs with no difference between OGD and CT grading.

CONCLUSION

Triphasic abdominal CT can be an invaluable tool in the diagnosis and grading of OVs during the COVID-19 pandemic.

Severe liver dysfunction complicating course of COVID-19 in the critically ill: multifactorial cause or direct viral effect?

Background

SARS-CoV-2 caused a pandemic and global threat for human health. Presence of liver injury was commonly reported in patients with coronavirus disease 2019 (COVID-19). However, reports on severe liver dysfunction (SLD) in critically ill with COVID-19 are lacking. We evaluated the occurrence, clinical characteristics and outcome of SLD in critically ill patients with COVID-19.

Methods

Clinical course and laboratory was analyzed from all patients with confirmed COVID-19 admitted to ICU of the university hospital. SLD was defined as: bilirubin ≥ 2 mg/dl or elevation of aminotransferase levels (> 20-fold ULN).

Results

72 critically ill patients were identified, 22 (31%) patients developed SLD. Presenting characteristics including age, gender, comorbidities as well as clinical presentation regarding COVID-19 overlapped substantially in both groups. Patients with SLD had more severe respiratory failure (paO₂/FiO_2: 82 (58–114) vs. 117 (83–155); p < 0.05). Thus, required more frequently mechanical ventilation (95% vs. 64%; p < 0.01), rescue therapies (ECMO) (27% vs. 12%; p = 0.106), vasopressor (95% vs. 72%; p < 0.05) and renal replacement therapy (86% vs. 30%; p < 0.001). Severity of illness was significantly higher (SAPS II: 48 (39–52) vs. 40 (32–45); p < 0.01). Patients with SLD and without presented viremic during ICU stay in 68% and 34%, respectively (p = 0.002). Occurrence of SLD was independently associated with presence of viremia [OR 6.359; 95% CI 1.336–30.253; p < 0.05] and severity of illness (SAPS II) [OR 1.078; 95% CI 1.004–1.157; p < 0.05]. Mortality was high in patients with SLD compared to other patients (68% vs. 16%, p < 0.001). After adjustment for confounders, SLD was independently associated with mortality [HR3.347; 95% CI 1.401–7.999; p < 0.01].

Conclusion

One-third of critically ill patients with COVID-19 suffer from SLD, which is associated with high mortality. Occurrence of viremia and severity of illness seem to contribute to occurrence of SLD and underline the multifactorial cause.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-021-00835-3.

In the eye of the storm: SARS-CoV-2 infection and replication at the ocular surface?

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) first emerged in December 2019 and spread quickly causing the coronavirus disease 2019 (COVID‐19) pandemic. Recent single cell RNA‐Seq analyses have shown the presence of SARS‐CoV‐2 entry factors in the human corneal, limbal, and conjunctival superficial epithelium, leading to suggestions that the human ocular surface may serve as an additional entry gateway and infection hub for SARS‐CoV‐2. In this article, we review the ocular clinical presentations of COVID‐19 and the features of the ocular surface that may underline the overall low ocular SARS‐CoV‐2 infection. We critically evaluate the studies performed in nonhuman primates, ex vivo organ culture ocular models, stem cell derived eye organoids and the differences in infection efficiency observed in different parts of human ocular surface epithelium. Finally, we highlight the additional work that needs to be carried out to understand the immune response of the ocular surface to SARS‐CoV‐2 infection, which can be translated into prophylactic treatments that may be applied to other organ systems.

Clinical characteristics and peripheral immunocyte subsets alteration of 85 COVID-19 deaths

Objectives: To retrospectively evaluate the clinical and immunological characteristics of patients who died of COVID-19 and to identify patients at high risk of death at an early stage and reduce their mortality.

Results: Total white blood cell count, neutrophil count and C-reactive protein were significantly higher in patients who died of COVID-19 than those who recovered from it (p < 0.05), but the total lymphocyte count, CD4 + T cells, CD8 + T cells, B cells and natural killer cells were significantly lower when compared in the same groups. Multiple logistic regression analysis showed that increased D-dimer, decreased CD4 + T cells and increased neutrophils were risk factors for mortality. Further multiple COX regression demonstrated that neutrophil ≥ 5.27 × 109/L increased the risk of death in COVID-19 patients after adjustment for age and gender. However, CD4 + T cells ≥ 260/μL appeared to reduce the risk of death.

Conclusion: SARS-CoV-2 infection led to a significant decrease of lymphocytes, and decreased CD4 + T cell count was a risk factor for COVID-19 patients to develop severe disease and death.

Methods: This study included 190 hospitalized COVID-19 patients from January 30, 2020 to March 4, 2020 in Wuhan, China, of whom 85 died and 105 recovered. Two researchers independently collected the clinical and laboratory data from electronic medical records.

COVID-19 in Children With Liver Disease

Background: The global pandemic caused by novel Coronavirus SARS-CoV-2 disease (COVID-19) is a major threat to the general population and for patients with pre-existing chronic conditions. We report data concerning SARS-CoV-2 infection in children with chronic liver disease (CLD). Methods: A literature review using the online database PubMed was performed to summarize available findings on the association between pre-existing liver disease and COVID-19 infection in children. Results: Children with COVID-19 have preserved effector and immunosuppressive components resulting in a milder disease compared to adults. The most common hepatic manifestation is an elevation of hepatic transaminases. Liver damage may be directly caused by viral infection of liver cells, by medications or by the chronic hypoxia seen in COVID-19 patients. A multicenter study reported that the majority of children with a CLD remained healthy during the outbreak. Similarly, studies reported that children on immunosuppressive treatment, including patients with autoimmune liver disease (AILD) and liver transplantation (LT), maintained good health during the outbreak without experiencing major complications even if infected with COVID-19. Conclusion: COVID-19-related liver injury presents with a mild elevation of transaminases, although its clinical significance is unclear. Children with CLD, including those with AILD and post-LT, do not have an increased risk for severe disease course of SARS-CoV-2 infection with little or no liver dysfunction. These data highlight the necessity to ensure normal standards of care while adhering to national Covid-19 guidelines, and particularly to maintain immunosuppressive medication to prevent relapse or rejection. Further research is required to evaluate the differences in clinical course between immunosuppressed adults and children and in particular whether asymptomatic infection is a concern.

Hepatic manifestations of COVID-19 and effect of remdesivir on liver function in patients with COVID-19 illness

COVID-19 has emerged as a major global health crisis since the first cases were reported in China in December 2019. Remdesivir is the only broad-spectrum antiviral approved by the US Food and Drug Administration to treat hospitalized patients with COVID-19 infection. Although the adverse effects of remdesivir are largely unknown, data from randomized controlled trials have demonstrated its deleterious effect on the liver. This review briefly addresses the hepatic manifestations of COVID-19 infection and the data regarding the efficacy and adverse effects of remdesivir on liver function when used in patients hospitalized with COVID-19. Through a literature search, we identified five randomized controlled trials, two case reports, and one case series, including a total of 2375 patients. Although mild transaminase elevation has been reported as a feature of COVID-19, there has been a concern of hepatotoxicity associated with the use of remdesivir. Based on the limited available data regarding the adverse effects of remdesivir on hepatic function, it is prudent to exercise caution by evaluating baseline liver function, avoiding the use of potentially hepatotoxic drugs, and closely monitoring liver function when using remdesivir in patients hospitalized with COVID-19.

SARS-CoV-2 and tissue damage: current insights and biomaterial-based therapeutic strategies

The effect of SARS-CoV-2 infection on humanity has gained worldwide attention and importance due to the rapid transmission, lack of treatment options and high mortality rate of the virus. While scientists across the world are searching for vaccines/drugs that can control the spread of the virus and/or reduce the risks associated with infection, patients infected with SARS-CoV-2 have been reported to have tissue/organ damage. With most tissues/organs having limited regenerative potential, interventions that prevent further damage or facilitate healing would be helpful. In the past few decades, biomaterials have gained prominence in the field of tissue engineering, in view of their major role in the regenerative process. Here we describe the effect of SARS-CoV-2 on multiple tissues/organs, and provide evidence for the positive role of biomaterials in aiding tissue repair. These findings are further extrapolated to explore their prospects as a therapeutic platform to address the tissue/organ damage that is frequently observed during this viral outbreak. This study suggests that the biomaterial-based approach could be an effective strategy for regenerating tissues/organs damaged by SARS-CoV-2.

Abnormal Liver Function Test in Patients Infected with Coronavirus (SARS-CoV-2): A Retrospective Single-Center Study from Spain

The outbreak of the novel coronavirus SARS-CoV-2 epidemic has rapidly spread and still poses a serious threat to healthcare systems worldwide. In the present study, electronic medical records containing clinical indicators related to liver injury in 799 COVID-19-confirmed patients admitted to a hospital in Madrid (Spain) were extracted and analyzed. Correlation between liver injury and disease outcome was also evaluated. Serum levels of Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), Gamma-glutamyltransferase (GGT), Alkaline phosphatase (ALP), Lactate dehydrogenase (LDH) and AST/ALT ratio were elevated above the Upper Limit of Normal (ULN) in 25.73%, 49.17%, 34.62%, 24.21%, 55.84% and 75% of patients, respectively. Interestingly, significant positive correlation between LDH levels and the AST/ALT ratio with disease outcome was found. Our data showed that SARS-CoV-2 virus infection leads to mild, but significant changes in serum markers of liver injury. The upregulated LDH levels as well as AST/ALT ratios upon admission may be used as additional diagnostic characteristic for COVID-19 patients.

Urinary trace elements in association with disease severity and outcome in patients with COVID-19

BACKGROUND

The dynamics of urinary trace elements in patients with COVID-19 still remains to be investigated.

METHODS

A retrospective study was performed on a cohort of 138 confirmed COVID-19 patients for their urinary levels of essential and/or toxic metals including chromium, manganese, copper, arsenic, selenium, cadmium, mercury, thallium and lead according to the different disease severity (severe or non-severe) and outcome (recovered or deceased).

RESULTS

Urinary concentrations of chromium, manganese, copper, selenium, cadmium, mercury and lead after creatinine adjustment were found to be higher in severe patients than the non-severe cases with COVID-19. And among the severe cases, these elements were also higher in the deceased group than the recovered group. When the weeks of the post-symptom onset were taken in account, the changes of these urinary elements were existed across the clinical course since the disease onset. These urinary elements were found to be mostly positively inter-correlated, and further positively correlated with other laboratory inflammatory parameters including serum cytokines (IL-1B, IL2R, IL6, IL8, IL10, TNFα), ferritin, and neutrophil count and white blood cell count. As a independently predictive factor, urinary creatinine-adjusted copper of ≥25.57 μg/g and ≥99.32 μg/g were associated with significantly increased risk of severe illness and fatal outcome in COVID-19, respectively.

CONCLUSIONS

These results suggest abnormities in urinary levels of the trace metals were tightly associated with the severe illness and fatal outcome of COVID-19.

What would be the impact of COVID-19 on liver function of a patient with chronic hepatitis B? About a case and literature review

Liver damage during COVID-19 disease has been described in numerous studies. Its mechanism is poorly understood. It is mainly reserved for severe forms and is manifested by abnormalities of the hepatic assessment and more particularly cytolysis. Particular attention must be paid to patients with chronic liver disease, both in terms of follow-up and treatment. We wanted to know the evolution of COVID-19 and its treatment, on the liver function of a 27-year-old patient followed for chronic non-cirrhotic hepatitis B at the Hassan II University Hospital in Fez. Our patient had stopped the antiviral B treatment and presented COVID-19 infection with minimal to moderate impairment. The initial evaluation showed cytolysis at 4 times upper limit of normal (ULN). Management consisted in the immediate resumption of Tenofovir in combination with hydroxychloroquine (HCQ) and azythromycin with good clinical and biological evolution.

COVID-19-associated liver injury: from bedside to bench

The outbreak of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been a global challenge since December 2019. Although most patients with COVID-19 exhibit mild clinical manifestations, in approximately 5% of these patients, the disease eventually progresses to severe lung injury or even multiorgan dysfunction. This situation represents various challenges to hepatology. In the context of liver injury in patients with COVID-19, several key problems need to be solved. For instance, it is important to determine whether SARS-CoV-2 can directly invade liver, especially when ACE2 appears to be negligibly expressed on hepatocytes. In addition, the mechanisms underlying liver dysfunction in COVID-19 patients are not fully understood, which are likely multifactorial and related to hyperinflammation, dysregulated immune responses, abnormal coagulation and drugs. Here, we systematically describe the potential pathogenesis of COVID-19-associated liver injury and propose several hypotheses about its etiopathogenesis.

Impact of liver enzymes on SARS-CoV-2 infection and the severity of clinical course of COVID-19

BACKGROUND AND AIM

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for the current pandemic, can have multi-organ impact. Recent studies show that liver injury could be a manifestation of the disease, and that liver disease could also be related to a worse prognosis. Our aim was to compare the characteristics of patients with severe coronavirus disease 2019 (COVID-19) due to SARS-CoV-2 who required intubation versus stable hospitalized patients to identify the early biochemical predictive factors of a severe course of COVID-19 and subsequent requirement for intubation, specifically in Mexican.

METHODS

This was an observational case-control study nested in a cohort study. Complete medical records of patients admitted for confirmed COVID-19 at a tertiary level center in Mexico City were reviewed. Clinical and biochemical data were collected, and the characteristics of patients who required invasive mechanical ventilation (IMV) (cases) were compared with stable hospitalized patients without ventilation (controls).

RESULTS

We evaluated 166 patients with COVID-19 due to SARS-CoV-2 infection; 114 (68.7%) were men, the mean age was 50.6 ± 13.3 years, and 27 (16.3%) required IMV. The comparative analysis between cases and controls showed (respectively) significantly lower blood oxygen saturation (SpO2) (73.5 ± 12.0% vs. 83.0 ± 6.8%, P < 0.0001) and elevated alanine aminotransferase (ALT) (128 (14-1123) IU/L vs. 33 (8-453) IU/L, P = 0.003), aspartate aminotransferase (AST) (214 (17-1247) vs. 44 (12-498) IU/L, P = 0.001), lactic dehydrogenase (LDH) (764.6 ± 401.9 IU/L vs. 461.0 ± 185.6 IU/L, P = 0.001), and D-dimer (3463 (524-34,227) ng/mL vs. 829 (152-41,923) ng/mL, P = 0.003) concentrations. Patients in the cases group were older (58.6 ± 12.7 years vs. 49.1 ± 12.8 years, P=0.001). Multivariate analysis showed that important factors at admission predicting the requirement for IMV during hospitalization for COVID-19 were AST ≥250 IU/L (odds ratio (OR) = 64.8, 95% confidence interval (CI) 7.5-560.3, P < 0.0001) and D-dimer ≥ 3500 ng/mL (OR = 4.1, 95% CI 1.2-13.7, P=0.02).

CONCLUSIONS

Our study confirms the importance of monitoring liver enzymes in hospitalized patients with COVID-19; seriously ill patients have significantly elevated AST and D-dimer concentrations, which have prognostic implications in the SARS-CoV-2 disease course.

Outcomes following SARS-CoV-2 infection in patients with chronic liver disease: An international registry study

BACKGROUND & AIMS

Chronic liver disease (CLD) and cirrhosis are associated with immune dysregulation, leading to concerns that affected patients may be at risk of adverse outcomes following SARS-CoV-2 infection. We aimed to determine the impact of COVID-19 on patients with pre-existing liver disease, which currently remains ill-defined.

METHODS

Between 25th March and 8th July 2020, data on 745 patients with CLD and SARS-CoV-2 (including 386 with and 359 without cirrhosis) were collected by 2 international registries and compared to data on non-CLD patients with SARS-CoV-2 from a UK hospital network.

RESULTS

Mortality was 32% in patients with cirrhosis compared to 8% in those without (p <0.001). Mortality in patients with cirrhosis increased according to Child-Pugh class (A [19%], B [35%], C [51%]) and the main cause of death was from respiratory failure (71%). After adjusting for baseline characteristics, factors associated with death in the total CLD cohort were age (odds ratio [OR] 1.02; 1.01-1.04), Child-Pugh A (OR 1.90; 1.03-3.52), B (OR 4.14; 2.4-7.65), or C (OR 9.32; 4.80-18.08) cirrhosis and alcohol-related liver disease (OR 1.79; 1.03-3.13). Compared to patients without CLD (n = 620), propensity-score-matched analysis revealed significant increases in mortality in those with Child-Pugh B (+20.0% [8.8%-31.3%]) and C (+38.1% [27.1%-49.2%]) cirrhosis. Acute hepatic decompensation occurred in 46% of patients with cirrhosis, of whom 21% had no respiratory symptoms. Half of those with hepatic decompensation had acute-on-chronic liver failure.

CONCLUSIONS

In the largest such cohort to date, we demonstrate that baseline liver disease stage and alcohol-related liver disease are independent risk factors for death from COVID-19. These data have important implications for the risk stratification of patients with CLD across the globe during the COVID-19 pandemic.

LAY SUMMARY

This international registry study demonstrates that patients with cirrhosis are at increased risk of death from COVID-19. Mortality from COVID-19 was particularly high among patients with more advanced cirrhosis and those with alcohol-related liver disease.

Challenging management of severe chronic disorders in acute pandemic situation: Chronic liver disease under COVID-19 pandemic as the proof-of-principle model to orchestrate the measures in 3PM context

Chronic liver disease management is a comprehensive approach requiring multi-professional expertise and well-orchestrated healthcare measures thoroughly organized by responsible medical units. Contextually, the corresponding multi-faceted chain of healthcare events is likely to be severely disturbed or even temporarily broken under the force majeure conditions such as global pandemics. Consequently, the chronic liver disease is highly representative for the management of any severe chronic disorder under lasting pandemics with unprecedented numbers of acutely diseased persons who, together with the chronically sick patient cohorts, have to be treated using the given capacity of healthcare systems with their limited resources. Current study aimed at exploring potentially negative impacts of the SARS CoV-2 outbreak on the quality of the advanced chronic liver disease (ACLD) management considering two well-classified parameters, namely, (1) the continuity of the patient registrations and (2) the level of mortality rates, comparing pre-COVID-19 statistics with these under the current pandemic in Slovak Republic. Altogether 1091 registrations to cirrhosis registry (with 60.8% versus 39.2% males to females ratio) were included with a median age of 57 years for patients under consideration. Already within the very first 3 months of the pandemic outbreak in Slovakia (lockdown declared from March 16, 2020, until May 20, 2020), the continuity of the patient registrations has been broken followed by significantly increased ACLD-related death rates. During this period of time, the total number of new registrations decreased by about 60% (15 registrations in 2020 versus 38 in 2018 and 38 in 2019). Corresponding mortality increased by about 52% (23 deaths in 2020 versus 10 in 2018 and 12 in 2019). Based on these results and in line with the framework of 3PM guidelines, the pandemic priority pathways (PPP) are strongly recommended for maintaining tertiary care uninterrupted. For the evidence-based implementation of PPP, creation of predictive algorithms and individualized care strategy tailored to the patient is essential. Resulting classification of measures is summarized as follows:The Green PPP Line is reserved for prioritized (urgent and comprehensive) treatment of patients at highest risk to die from ACLD (tertiary care) as compared to the risk from possible COVID-19 infection.The Orange PPP Line considers patients at middle risk of adverse outcomes from ACLD with re-addressing them to the secondary care. As further deterioration of ACLD is still probable, pro-active management is ascertained with tertiary center serving as the 24/7 telemedicine consultation hub for a secondary facility (on a physician-physician level).The Red PPP Line is related to the patients at low risk to die from ACLD, re-addressing them to the primary care. Since patients with stable chronic liver diseases without advanced fibrosis are at trivial inherent risk, they should be kept out of the healthcare setting as far as possible by the telemedical (patient-nurse or patient- physician) measurements. The assigned priority has to be monitored and re-evaluated individually-in intervals based on the baseline prognostic score such as MELD. The approach is conform with principles of predictive, preventive and personalized medicine (PPPM / 3PM) and demonstrates a potential of great clinical utility for an optimal management of any severe chronic disorder (cardiovascular, neurological and cancer) under lasting pandemics.

Pathological findings in the postmortem liver of patients with coronavirus disease 2019 (COVID-19)

Although coronavirus disease 2019 (COVID-19) is transmitted via respiratory droplets, there are multiple gastrointestinal and hepatic manifestations of the disease, including abnormal liver-associated enzymes. However, there are not many published articles on the pathological findings in the liver of patients with COVID-19. We collected the clinical data from 17 autopsy cases of patients with COVID-19 including age, sex, Body mass index (BMI), liver function test (alanine aminotransaminase (ALT), aspartate aminotransaminase (AST), alkaline phosphatase (ALP), direct bilirubin, and total bilirubin), D-dimer, and anticoagulation treatment. We examined histopathologic findings in postmortem hepatic tissue, immunohistochemical (IHC) staining with antibody against COVID-19 spike protein, CD68 and CD61, and electron microscopy. We counted the number of megakaryocytes in liver sections from these COVID-19-positive cases. Abnormal liver-associated enzymes were observed in 12 of 17 cases of COVID-19 infection. With the exception of three cases that had not been tested for D-dimer, all 14 patients' D-dimer levels were increased, including the cases that received varied doses of anticoagulation treatment. Microscopically, the major findings were widespread platelet-fibrin microthrombi, steatosis, histiocytic hyperplasia in the portal tract, mild lobular inflammation, ischemic-type hepatic necrosis, and zone 3 hemorrhage. Rare megakaryocytes were found in sinusoids. COVID-19 IHC demonstrates positive staining of the histiocytes in the portal tract. Under electron microscopy, histiocyte proliferation is present in the portal tract containing lipid droplets, lysosomes, dilated ribosomal endoplasmic reticulum, microvesicular bodies, and coronavirus. The characteristic findings in the liver of patients with COVID-19 include numerous amounts of platelet-fibrin microthrombi, as well as various degrees of steatosis and histiocytic hyperplasia in the portal tract. Possible mechanisms are also discussed.

Liver disease and outcomes among COVID-19 hospitalized patients - A systematic review and meta-analysis

INTRODUCTION AND OBJECTIVES

The coronavirus disease 2019 (COVID-19) pandemic has been a challenge globally. In severe acute respiratory syndrome (SARS) epidemic 60% of patients had hepatic injury, due to phylogenetic similarities of the viruses it is assumed that COVID-19 is associated with acute liver injury. In this meta-analysis, we aim to study the occurrence and association of liver injury, comorbid liver disease and elevated liver enzymes in COVID-19 confirmed hospitalizations with outcomes.

MATERIALS AND METHODS

Data from observational studies describing comorbid chronic liver disease, acute liver injury, elevated aspartate aminotransferase (AST), alanine aminotransferase (ALT) levels and outcomes of COVID-19 hospitalized patients from December 1, 2019, to June 30, 2020 was extracted following PRISMA guidelines. Adverse outcomes were defined as admission to intensive care unit (ICU), oxygen saturation <90%, invasive mechanical ventilation (IMV), severe disease and in-hospital mortality. Odds ratio (OR) and 95% confidence interval (95% CI) were obtained.

RESULTS

24 studies with 12,882 confirmed COVID-19 patients were included. Overall prevalence of CM-CLD was 2.6%, COVID-19-ALI was 26.5%, elevated AST was 41.1% and elevated ALT was 29.1%. CM-CLD had no significant association with poor outcomes (pooled OR: 0.96; 95% CI: 0.71-1.29; p=0.78). COVID-19-ALI (1.68;1.04-2.70; p=0.03), elevated AST (2.98; 2.35-3.77; p<0.00001) and elevated ALT (1.85;1.49-2.29; p<0.00001) were significantly associated with higher odds of poor outcomes.

CONCLUSION

Our meta-analysis suggests that acute liver injury and elevated liver enzymes were significantly associated with COVID-19 severity. Future studies should evaluate changing levels of biomarkers amongst liver disease patients to predict poor outcomes of COVID-19 and causes of liver injury during COVID-19 infection.

Lipid metabolism changes in patients with severe COVID-19

Background

We investigated the dynamic changes in lipid profiles and their correlations with disease severity and clinical outcome in patients with severe COVID-19.

Methods

We retrospectively reviewed 519 severe COVID-19 patients with confirmed outcomes (discharged or deceased), admitted to the West Court of Union Hospital in Wuhan, China, between 29 January and 8 April 2020.

Results

Altogether, 424 severe COVID-19 patients, including 34 non-survivors and 390 survivors, were included in the final analyses. During hospitalization, low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A-I (apoA-I) showed an increasing trend in survivors, but showed a downward trend in non-survivors. The serum concentrations of HDL-C and apoA-I were inversely correlated with C-reactive protein (CRP), length of hospital stay of survivors, and disease severity scores. For in-hospital deaths, the areas under the receiver operating characteristic curves (AUCs) of the ratios of CRP/HDL-C and CRP/apoA-I at admission were 0.84 and 0.83, respectively. Moreover, patients with high ratios of CRP/HDL-C (＞77.39) or CRP/apoA-I (＞72.37) had higher mortality rates during hospitalization (log-rank p < 0.001). Logistic regression analysis demonstrated that hypertension, lactate dehydrogenase, SOFA score, and High CRP/HDL-C ratio were independent predictors of in-hospital mortality.

Conclusions

During severe COVID-19, HDL-C and apoA-I concentrations are dramatically decreased in non-survivors. Moreover, High CRP/HDL-C ratio is significantly associated with an increase in mortality and a poor prognosis.

Coronavirus (SARS-CoV-2) in gastroenterology and its current epidemiological situation: An updated review until January 2021

Coronaviruses are positive-sense single-strand RNA viruses that infect amphibians, birds, and mammals. Coronavirus Disease 2019 (COVID-19) has become a major health problem caused by one of the coronaviruses called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It has spread fast throughout the globe since its first identification in Wuhan, China, in December 2019. Although COVID-19 is principally defined by its respiratory symptoms, it is now clear that the virus can also affect the digestive system causing gastrointestinal (GI) symptoms like diarrhea, loss of appetite, nausea/vomiting, and abdominal pain as a major complaint. GI symptoms could be the initial signs of preceding respiratory signs, carrying a potential for slowed investigation and raised disease transmission opportunities. Various studies recognized the COVID-19 RNA in stool specimens of infected patients, and its viral receptor angiotensin-converting enzyme-2 (ACE-2) is highly expressed in GI epithelial cells. Many cases were reported negative using nasopharyngeal/oropharyngeal swabs and finally, SARS-CoV-2 RNA was detected in their anal/rectal swabs and stool specimens. These suggest that COVID-19 can actively infect and replicate in the GI tract. In this review, we elaborate on the close relationship between SARS-CoV-2 and the digestive system, focusing on the current status in the field of COVID-19 in gastroenterology, liver injury, endoscopy, inflammatory bowel disease, imaging, and the potential underlying mechanisms with illustrating the current epidemiological status regarding this pandemic.

Microvascular Angiopathic Consequences of COVID-19

The coronavirus disease-2019 (COVID-19) pandemic has rapidly spread across the world. The disease is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which first appeared in Wuhan, China in December, 2019. Ever increasing data is continuing to emerge about the impact of COVID-19 on cardiovascular tissue and other organ system. Clinical features associated with COVID-19 suggest that endothelial cell dysfunction and microvascular thrombosis are to a large extent contributing to resultant multi-organ complications. This review is aimed at highlighting the critical aspects associated with COVID-19 and its presumed microvascular angiopathic consequences on the cardiovascular system leading to multi-organ dysfunction.

Association of coagulopathy with liver dysfunction in patients with COVID-19

AIM

Liver dysfunction is sometimes observed in patients with coronavirus disease 2019 (COVID-19), but most studies are from China, and the frequency in other countries is unclear. In addition, previous studies suggested several mechanisms of liver damage, but precise or additional mechanisms are not clearly elucidated. Therefore, we examined COVID-19 patients to explore the proportion of patients with liver dysfunction and also the factors associated with liver dysfunction.

METHODS

We retrospectively examined 60 COVID-19 patients hospitalized at the Hospital affiliated with The Institute of Medical Science, The University of Tokyo (Tokyo, Japan). Patients who presented ≥40 U/L alanine aminotransferase (ALT) levels at least once during their hospitalization were defined as high-ALT patients, and the others as normal-ALT patients. The worst values of physical and laboratory findings during hospitalization for each patient were extracted for the analyses. Univariable and multivariable logistic regression models with bootstrap (for 1000 times) were carried out.

RESULTS

Among 60 patients, there were 31 (52%) high-ALT patients. The high-ALT patients were obese, and had significantly higher levels of D-dimer and fibrin/fibrinogen degradation products, as well as white blood cell count, and levels of C-reactive protein, ferritin, and fibrinogen. Multivariable analysis showed D-dimer and white blood cells as independent factors.

CONCLUSIONS

Considering that higher D-dimer level and white blood cell count were independently associated with ALT elevation, liver dysfunction in COVID-19 patients might be induced by microvascular thrombosis in addition to systemic inflammation.

[Histopathological features due to the SARS-CoV-2]

The infection due to the SARS-CoV-2 leads lesions mainly observed at the respiratory tract level, but not exclusively. The analyses of these lesions benefited from different autopsy studies. Thus, these lesions were observed in different organs, tissues and cells. These observations allowed us to rapidly improve the knowledge of the pathophysiological mechanisms associated with this emergent infectious disease. The virus can be detected in formalin fixed paraffin embedded tissues using immunohistochemistry, in situ hybridization, molecular biology and/or electron microscopy approaches. However, many uncertainties are still present concerning the direct role of the SARS-CoV-2 on the different lesions observed in different organs, outside the lung, such as the heart, the brain, the liver, the gastrointestinal tract, the kidney and the skin. In this context, it is pivotal to keep going to increase the different tissue and cellular studies in the COVID-19 positive patients aiming to better understanding the consequences of this new infectious disease, notably considering different epidemiological and co-morbidities associated factors. This could participate to the development of new therapeutic strategies too. The purpose of this review is to describe the main histological and cellular lesions associated with the infection due to the SARS-CoV-2.

The risks of liver injury in COVID-19 patients and pharmacological management to reduce or prevent the damage induced

BACKGROUND

The global pandemic COVID-19 caused by the new coronavirus SARS-CoV-2 has already caused about 1.4 million deaths, and to date, there are no effective or direct antiviral vaccines. Some vaccines are in the last stages of testing. Overall mortality rates vary between countries, for example, from a minimum of 0.05% in Singapore to a maximum of 9.75 in Mexico; however, mortality and severity of COVID-19 are higher in the elderly and in those with comorbidities already present such as diabetes, hypertension, and heart disease.

MAIN TEXT

Recent evidence has shown that an underlying liver disease can also be a risk factor, and SARS-CoV-2 itself can cause direct or indirect damage to liver tissue through multisystem inflammation generated especially in the more severe stages. In the current pandemic, liver dysfunction has been observed in 14-53% of patients with severe COVID-19. In addition, drugs administered during infection may be an additional factor of liver damage. The mechanism of cellular penetration of the virus that occurs by viral entry is through the receptors of the angiotensin 2 conversion enzyme (ACE-2) host that are abundantly present in type II pneumocytes, heart cells, but also liver cholangiocytes.

CONCLUSION

In this manuscript, we describe the clinical management aimed at preserving the liver or reducing the damage caused by COVID-19 and anti-COVID-19 drug treatments.

Clinical features and potential mechanism of coronavirus disease 2019-associated liver injury

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, has posed a serious threat to global public health security. With the increase in the number of confirmed cases globally, the World Health Organization has declared the outbreak of COVID-19 an international public health emergency. Despite atypical pneumonia as the primary symptom, liver dysfunction has also been observed in many clinical cases and is associated with the mortality risk in patients with COVID-19, like severe acute respiratory syndrome and Middle East respiratory syndrome. Here we will provide a schematic overview of the clinical characteristics and the possible mechanisms of liver injury caused by severe acute respiratory syndrome coronavirus 2 infection, which may provide help for optimizing the management of liver injury and reducing mortality in COVID-19 patients.

SARS-CoV-2 infection associated with hepatitis in an infant with X-linked severe combined immunodeficiency

X-linked severe combined immunodeficiency (X-SCID) is a disorder of adaptive immunity caused by mutations in the IL-2 receptor common gamma chain gene resulting in deficiencies of T and natural killer cells, coupled with severe dysfunction in B cells. X-SCID is lethal without allogeneic stem cell transplant or gene therapy due to opportunistic infections. An infant with X-SCID became infected with SARS-CoV-2 while awaiting transplant. The patient developed severe hepatitis without the respiratory symptoms typical of COVID-19. He was treated with convalescent plasma, and thereafter was confirmed to have SARS-CoV-2 specific antibodies, as detected with a microfluidic antigen array. After resolution of the hepatitis, he received a haploidentical CD34 selected stem cell transplant, without conditioning, from his father who had recovered from COVID-19. SARS CoV-2 was detected via RT-PCR on nasopharyngeal swabs until 61 days post transplantation. He successfully engrafted donor T and NK cells, and continues to do well clinically.

Liver function recovery of COVID-19 patients after discharge, a follow-up study

Objective: The aim of this study was to observe the liver function recovery of COVID-19 patients after discharge. Patients and Methods: A total of 253 discharged COVID-19 patients in Shenzhen city, China were selected. The clinical characteristics of these patients were assessed. A 2-month follow-up and laboratory hematology test were performed to examine the status of patients' liver function. Results: Patients combined with liver diseases, especially fatty liver, are more likely to progress to severe condition (P<0.05). Patients in severe condition and those with liver diseases have higher rates of liver injuries during hospitalization, characterized by a significant increase in alanine aminotransferase (ALT) and aspartate aminotransferase (AST, P<0.01). The ALT, AST/ALT, gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), total protein (TP), albumin (ALB), and A/G levels showed significant differences in comparison with the control group (P<0.05, and P<0.001); and the outlier ratio of A/G, ALT, GGT and ALP of patients remained abnormal higher within 14 days after discharge (P<0.001). Liver injuries of COVID-19 patients may be related to the epidemiological characteristics, clinical indexes, basic diseases, symptoms, drug treatment during hospitalization and the complications. Indicators of liver function were correlated with cardiac function, renal function, thyroid function, lipid metabolism, glucose metabolism, immune index, leukocyte, erythrocyte, hemoglobin and platelet related indexes. The outlier ratio of TP, ALB and GLB remained extremely low throughout the follow-up period; the outlier ratio of ALT, AST and GGT decreased below 10% from a high level at 40 days after discharged. However, the outlier ratio of A/G, AST/ALT and ALP remained high during the follow-up period. Conclusions: Abnormal liver function might indicate worse recovery of COVID-19 patients. Changes in liver function should be emphasized during long-term follow-up of COVID-19 patients after hospital discharge; the necessity of employing appropriate interventions for liver function repair should be emphasized.

Pathophysiological mechanisms of liver injury in COVID-19

The recent outbreak of coronavirus disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has resulted in a world-wide pandemic. Disseminated lung injury with the development of acute respiratory distress syndrome (ARDS) is the main cause of mortality in COVID-19. Although liver failure does not seem to occur in the absence of pre-existing liver disease, hepatic involvement in COVID-19 may correlate with overall disease severity and serve as a prognostic factor for the development of ARDS. The spectrum of liver injury in COVID-19 may range from direct infection by SARS-CoV-2, indirect involvement by systemic inflammation, hypoxic changes, iatrogenic causes such as drugs and ventilation to exacerbation of underlying liver disease. This concise review discusses the potential pathophysiological mechanisms for SARS-CoV-2 hepatic tropism as well as acute and possibly long-term liver injury in COVID-19.

SARS-CoV-2 infection in patients with a normal or abnormal liver

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), a novel coronavirus causing coronavirus disease 19 (COVID-19), with an estimated 22 million people infected worldwide so far although involving primarily the respiratory tract, has a remarkable tropism for the liver and the biliary tract. Patients with SARS-CoV-2 infection and no antecedent liver disease may display evidence of cytolytic liver damage, proportional to the severity of COVID-19 but rarely of clinical significance. The mechanism of hepatocellular injury is unclear and possibly multifactorial. The clinical impact of SARS-CoV-2 infection in patients with underlying chronic liver disease, a cohort whose global size is difficult to estimate, has been assessed appropriately only recently and data are still evolving. Patients with cirrhosis are at higher risk of developing severe COVID-19 and worse liver-related outcomes as compared to those with non-cirrhotic liver disease. OLT patients have an intermediate risk. Specific interventions in order to reduce the risk of transmission of infection among this high-risk population have been outlined by international societies, together with recommendations for modified treatment and follow-up regimens during the COVID-19 pandemic. When a vaccine against SARS-CoV-2 becomes available, patients with fibrotic liver disease and those with OLT should be considered as prime targets for prophylaxis of COVID-19, as all other highly susceptible subjects.

SARS-Cov-2 infection in transplant-related biology: Where do we stand?

Since December 2019, the novel coronavirus (SARS-CoV-2) emerged in Wuhan and rapidly spread throughout the world. There are nearly 3 951 905 confirmed cases of novel coronary pneumonia and more than 275 067 deaths worldwide, [JHU data-09/05/2020, https://www.arcgis.com/apps/opsdashboard/index.html#/bda7594740fd40299423467b48e9ecf6]. A great number of patients contracted SARS-Cov-2 pneumonia (COVID-19). SARS-CoV-2 invades human target cells through receptor angiotensin-converting enzyme II (ACE2), which are expressed in the lung, kidney, and ileum and mediate inflammatory responses and immune activities. High plasma levels of proinflammatory cytokines were detected in the infected patients. These factors may predispose transplant patients to high risk of poor outcomes. Therefore, transplant patients might be affected by this coronavirus infection and protection of allografts should receive special attention during this outbreak. In the present study we attempt to delineate the transplant-related biology of SARS-CoV-2 infection.

Evaluation of serum hepatic enzyme activities in different COVID-19 phenotypes

Coronavirus disease 2019 (COVID-19) is a newly emerging infectious disease. Our understanding of the clinical characteristics of liver damage and the relationship with disease severity in COVID-19 is still limited. To investigate the serum hepatic enzyme activities in different phenotypes of COVID-19 patients, evaluate their relationship with the illness severity and analyze the correlation of glycyrrhizin treatment and abnormal liver enzyme activities, one hundred and forty-seven patients with COVID-19 were enrolled in a retrospective study that investigated hepatic dysfunction. Liver alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactic dehydrogenase (LDH), Y-glutamyl transferase (GGT), superoxide dismutase (SOD), and alkaline phosphatase (ALP) were analyzed in these patients. Patients with diammonium glycyrrhizinate (DG) treatment were further investigated. Of the 147 patients, 56 (38.1%) had abnormal ALT activity and 80 (54.4%) had abnormal AST activity. The peak of abnormal hepatic enzyme activities occurred at 3 to 6 days after on admission. Serum AST and LDH levels were elevated, while the SOD level was decreased in severe and critical patients, compared with mild cases. DG treatment may alleviate the abnormal liver enzyme activities in non-critical COVID-19 patients. Abnormal liver functions may be observed in patients with COVID-19, and were associated with SARS-CoV-2-induced acute liver damage. Glycyrrhizin treatment may be an effective therapeutic approach for the outcome of abnormal hepatic enzyme activities in severe COVID-19 cases. Serum hepatic enzyme tests may reflect the illness severity and should be monitored.

Clinical Characteristics and Risk Factors in Coronavirus Disease 2019 Patients with Liver Injury

BACKGROUND Emerging studies noted that liver injury in coronavirus disease 2019 (COVID-19) patients may be induced by virus-mediated inflammation, which was confirmed by liver pathology. The aim of this study was to observe clinical characteristics and explore risk factors in COVID-19 patients with liver injury. MATERIAL AND METHODS In this retrospective study, 40 confirmed COVID-19 patients with normal alanine transaminase (ALT) on admission were divided into a group of normal ALT patients whose ALT was always less than 40 U/l during hospitalization and a group of elevated ALT patients whose ALT was at least once more than 40 U/l after admission. Clinical data, especially virus-induced inflammatory parameters, were analyzed for risk factors and predictive value. The Mann-Whitney U test and t test for comparing means and logistic regression were performed for analysis of risk factors. Area under the ROC curve was used for predictive values. RESULTS Sixteen of 40 (40.0%) patients developed elevated ALT, many of them with more severe COVID-19. The highest ALT level was 101 U/l. The risk factors for liver injury were C-reactive protein (CRP), interleukin 6 (IL6), erythrocyte sedimentation rate (ESR), CD8+T cell count, and severity of disease, and CRP (OR 1.13, 95% CI 1.045-1.222, p=0.002) was the independent risk factor. CONCLUSIONS Liver injury in COVID-19 patients was mild and associated with inflammatory markers, especially CRP, which suggests that liver injury may be induced by virus-mediated inflammation in COVID-19 patients.

Diabetic patients with COVID-19 need more attention and better glycemic control

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a pandemic disease spreading all over the world and has aroused global concerns. The increasing mortality has revealed its severity. It is important to distinguish severe patients and provide appropriate treatment and care to prevent damages. Diabetes is reported to be a common comorbidity in COVID-19 patients and associated with higher mortality. We attempted to clarify the relationship between diabetes and COVID-19 patients' severity.

AIM

To determine the role of type 2 diabetes in COVID-19 patients.

METHODS

To study the relationship between diabetes and COVID-19, we retrospectively collected 61 patients' data from a tertiary medical center in Wuhan. All the patients were diagnosed with laboratory-confirmed COVID-19 and admitted to the center from February 13 to March 1, 2020. Patients' age, sex, laboratory tests, chest computed tomography findings, capillary blood glucose (BG), and treatments were collected and analyzed. Fisher exact test was used for categorical data. Univariate and multivariate logistic regressions were used to explore the relationship between clinical characteristics and patients' severity.

RESULTS

In the 61 patients, the comorbidity of type 2 diabetes, hypertension, and heart diseases were 24.6% (15 out of 61), 37.7% (23 out of 61), and 11.5% (7 out of 61), respectively. The diabetic group was related to more invasive treatments (P = 0.02) and severe status (P = 0.003). In univariate logistic regression, histories of diabetes (OR = 7.13, P = 0.003), hypertension (OR = 3.41, P = 0.039), and hepatic dysfunction (OR = 7.69, P = 0.002) were predictors of patients' severity while heart disease (OR = 4.21, P = 0.083) and large lung involvement (OR = 2.70, P = 0.093) also slightly exacerbated patients' conditions. In the multivariate analysis, diabetes (OR = 6.29, P = 0.016) and hepatic dysfunction (OR = 5.88, P = 0.018) were risk factors for severe patients. Diabetic patients showed elevated BG in 61.7% of preprandial tests and 33.3% of postprandial tests, revealing the limited control of glycemia in COVID-19 patients.

CONCLUSION

A history of type 2 diabetes is correlated with invasive treatments and severe status. Suboptimal glycemic control and hepatic dysfunction have negative effects on severity status and may lead to the exacerbation of COVID-19 patients.

Coronavirus Disease (COVID-19) Caused by (SARS-CoV-2) Infections: A Real Challenge for Human Gut Microbiota

The current COVID-19 pandemic is a great challenge for worldwide researchers in the human microbiota area because the mechanisms and long-term effects of the infection at the GI level are not yet deeply understood. In the current review, scientific literature including original research articles, clinical studies, epidemiological reports, and review-type articles concerning human intestinal infection with SARS-CoV-2 and the possible consequences on the microbiota were reviewed. Moreover, the following aspects pertaining to COVID-19 have also been discussed: transmission, resistance in the human body, the impact of nutritional status in relation to the intestinal microbiota, and the impact of comorbid metabolic disorders such as inflammatory bowel disease (IBS), obesity, and type two diabetes (T2D). The articles investigated show that health, age, and nutritional status are associated with specific communities of bacterial species in the gut, which could influence the clinical course of COVID-19 infection. Fecal microbiota alterations were associated with fecal concentrations of SARS-CoV-2 and COVID-19 severity. Patients suffering from metabolic and gastrointestinal (GI) disorders are thought to be at a moderate-to-high risk of infection with SARS-CoV-2, indicating the direct implication of gut dysbiosis in COVID-19 severity. However, additional efforts are required to identify the initial GI symptoms of COVID-19 for possible early intervention.

Pathophysiological mechanisms of liver injury in COVID-19

The recent outbreak of coronavirus disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has resulted in a world-wide pandemic. Disseminated lung injury with the development of acute respiratory distress syndrome (ARDS) is the main cause of mortality in COVID-19. Although liver failure does not seem to occur in the absence of pre-existing liver disease, hepatic involvement in COVID-19 may correlate with overall disease severity and serve as a prognostic factor for the development of ARDS. The spectrum of liver injury in COVID-19 may range from direct infection by SARS-CoV-2, indirect involvement by systemic inflammation, hypoxic changes, iatrogenic causes such as drugs and ventilation to exacerbation of underlying liver disease. This concise review discusses the potential pathophysiological mechanisms for SARS-CoV-2 hepatic tropism as well as acute and possibly long-term liver injury in COVID-19.

Innate immunity plays a key role in controlling viral load in COVID-19: mechanistic insights from a whole-body infection dynamics model

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a pathogen of immense public health concern. Efforts to control the disease have only proven mildly successful, and the disease will likely continue to cause excessive fatalities until effective preventative measures (such as a vaccine) are developed. To develop disease management strategies, a better understanding of SARS-CoV-2 pathogenesis and population susceptibility to infection are needed. To this end, physiologically-relevant mathematical modeling can provide a robust in silico tool to understand COVID-19 pathophysiology and the in vivo dynamics of SARS-CoV-2. Guided by ACE2-tropism (ACE2 receptor dependency for infection) of the virus, and by incorporating cellular-scale viral dynamics and innate and adaptive immune responses, we have developed a multiscale mechanistic model for simulating the time-dependent evolution of viral load distribution in susceptible organs of the body (respiratory tract, gut, liver, spleen, heart, kidneys, and brain). Following calibration with in vivo and clinical data, we used the model to simulate viral load progression in a virtual patient with varying degrees of compromised immune status. Further, we conducted global sensitivity analysis of model parameters and ranked them for their significance in governing clearance of viral load to understand the effects of physiological factors and underlying conditions on viral load dynamics. Antiviral drug therapy, interferon therapy, and their combination was simulated to study the effects on viral load kinetics of SARS-CoV-2. The model revealed the dominant role of innate immunity (specifically interferons and resident macrophages) in controlling viral load, and the importance of timing when initiating therapy following infection.

Hereditary Hypofibrinogenemia with Hepatic Storage

Fibrinogen is a 340-kDa plasma glycoprotein constituted by two sets of symmetrical trimers, each formed by the Aα, Bβ, and γ chains (respectively coded by the FGA, FGB, and FGG genes). Quantitative fibrinogen deficiencies (hypofibrinogenemia, afibrinogenemia) are rare congenital disorders characterized by low or unmeasurable plasma fibrinogen antigen levels. Their genetic basis is represented by mutations within the fibrinogen genes. To date, only eight mutations, all affecting a small region of the fibrinogen γ chain, have been reported to cause hereditary hypofibrinogenemia with hepatic storage (HHHS), a disorder characterized by protein aggregation in the endoplasmic reticulum, hypofibrinogenemia, and liver disease of variable severity. Here, we will briefly review the clinic characteristics of HHHS patients and the histological feature of their hepatic inclusions, and we will focus on the molecular genetic basis of this peculiar type of coagulopathy.

Paracetamol-Induced Glutathione Consumption: Is There a Link With Severe COVID-19 Illness?

COVID-19 pandemic is posing an unprecedented sanitary threat: antiviral and host-directed medications to treat the disease are urgently needed. A great effort has been paid to find drugs and treatments for hospitalized, severely ill patients. However, medications used for the domiciliary management of early symptoms, notwithstanding their importance, have not been and are not presently regarded with the same attention and seriousness. In analogy with other airways viral infections, COVID-19 patients in the early phase require specific antivirals (still lacking) and non-etiotropic drugs to lower pain, fever, and control inflammation. Non-steroidal anti-inflammatory drugs (NSAIDs) and paracetamol (PAC) are widely used as non-etiotropic agents in common airways viral infections and hence are both theoretically repurposable for COVID-19. However, a warning from some research reports and National Authorities raised NSAIDs safety concerns because of the supposed induction of angiotensin-converting enzyme 2 (ACE2) levels (the receptor used by SARS-CoV2 to enter host airways cells), the increased risk of bacterial superinfections and masking of disease symptoms. As a consequence, the use of NSAIDs was, and is still, discouraged while the alternative adoption of paracetamol is still preferred. On the basis of novel data and hypothesis on the possible role of scarce glutathione (GSH) levels in the exacerbation of COVID-19 and of the GSH depleting activity of PAC, this commentary raises the question of whether PAC may be the better choice.