Systemic viral infections and collateral damage in the liver

Liver injury, SARS-COV-2 infection and COVID-19: What physicians should really know?

BACKGROUND & AIMS

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for coronavirus disease 2019 (COVID-19), which in males, especially in advanced age, can sometimes evolve into acute respiratory distress syndrome. In addition, mild to moderate alterations in liver function tests (LFTs) have been reported in the worst affected patients. Our review aims to analyse data on the incidence and prognostic value of LFT alterations, the underlying mechanisms and the management of pre-existing liver disease in COVID-19 affected patients.

METHODS

We searched available literature through online PubMed database using terms as "SARS-CoV-2," "Liver damage," "Liver Function tests," "COVID-19," "pre-existing liver disease," "drug-induced liver injury."

RESULTS

Available evidence suggest that there could be a relationship between SARS-CoV-2 infection and liver damage, although the underlying involved mechanism remains unclear. Cohort studies have shown that high ALT levels, low platelet counts and low albumin levels at admission and during hospitalisation are associated with a high mortality rate. Unfortunately, little is known about the impact of COVID-19 on pre-existing liver damage. While chronic viral infections or NAFLD are associated with an increased risk of COVID-19 progression, patients with cirrhosis may have increased susceptibility to SARS-CoV-2 infection due to their systemic immunocompromised status. DILI seems common among hospitalised patient with severe pneumonia.

CONCLUSION

Mild to moderate liver impairment during Covid-19 is common, especially in patients with pre-existing liver disease. Further studies should be performed in order to understand how pre-existing liver conditions may influence and worsen progression of liver disease in COVID-19 patients.

Pathological findings in organs and tissues of patients with COVID-19: A systematic review

BACKGROUND

Coronavirus disease (COVID-19) is the pandemic caused by SARS-CoV-2 that has caused more than 2.2 million deaths worldwide. We summarize the reported pathologic findings on biopsy and autopsy in patients with severe/fatal COVID-19 and documented the presence and/or effect of SARS-CoV-2 in all organs.

METHODS AND FINDINGS

A systematic search of the PubMed, Embase, MedRxiv, Lilacs and Epistemonikos databases from January to August 2020 for all case reports and case series that reported histopathologic findings of COVID-19 infection at autopsy or tissue biopsy was performed. 603 COVID-19 cases from 75 of 451 screened studies met inclusion criteria. The most common pathologic findings were lungs: diffuse alveolar damage (DAD) (92%) and superimposed acute bronchopneumonia (27%); liver: hepatitis (21%), heart: myocarditis (11.4%). Vasculitis was common only in skin biopsies (25%). Microthrombi were described in the placenta (57.9%), lung (38%), kidney (20%), Central Nervous System (CNS) (18%), and gastrointestinal (GI) tract (2%). Injury of endothelial cells was common in the lung (18%) and heart (4%). Hemodynamic changes such as necrosis due to hypoxia/hypoperfusion, edema and congestion were common in kidney (53%), liver (48%), CNS (31%) and GI tract (18%). SARS-CoV-2 viral particles were demonstrated within organ-specific cells in the trachea, lung, liver, large intestine, kidney, CNS either by electron microscopy, immunofluorescence, or immunohistochemistry. Additional tissues were positive by Polymerase Chain Reaction (PCR) tests only. The included studies were from numerous countries, some were not peer reviewed, and some studies were performed by subspecialists, resulting in variable and inconsistent reporting or over statement of the reported findings.

CONCLUSIONS

The main pathologic findings of severe/fatal COVID-19 infection are DAD, changes related to coagulopathy and/or hemodynamic compromise. In addition, according to the observed organ damage myocarditis may be associated with sequelae.

COVID-19 in a Patient with Liver Cirrhosis

BACKGROUND The severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), which manifests mainly as a respiratory condition, has become a global pandemic that causes coronavirus disease-2019 (COVID-19). Although the symptoms remain mild in most patients, the elderly and patients with previous comorbidities have higher rates of morbidity and mortality. Patients with liver cirrhosis, especially after decompensation, may be more susceptible to SARS-CoV-2 infection due to systemic immune dysfunction. CASE REPORT The patient was a 51-year-old man who was hypertensive, an ex-alcoholic abstinent for 6 months, and a smoker. He was diagnosed with alcoholic liver cirrhosis in July 2019, and was using norfloxacin at home for secondary prophylaxis of bacterial peritonitis. He was also using furosemide and spironolactone to control ascites and propranolol for primary prophylaxis of esophageal varices. The patient entered our hospital in July 2020 with cough, dyspnea, runny nose, diarrhea, and fever. During hospitalization, we confirmed infection by COVID-19 and secondary nosocomial pulmonary infection. Chest tomography compatible with ground-glass standard was performed. The patient developed the need for auxiliary oxygen but without invasive mechanical ventilation. The patient received dexamethasone 6 mg/day and broad-spectrum antibiotic therapy (he was started on cefepime but switched to meropenem). At the end of the 14-day isolation period, he was discharged with improved respiratory status. CONCLUSIONS Despite high mortality rates in patients with advanced cirrhosis who become infected with COVID-19, we report a case with a favorable outcome. Success has been achieved with the use of medications in studies of broad-spectrum antibiotics and the rapid detection of complications caused by the virus. Further studies in SARS-CoV-2 patients with chronic liver disease are needed.

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.

Abnormal liver tests in patients with SARS-CoV-2 or influenza - prognostic similarities and temporal disparities

Background & Aims

Abnormal liver tests are common in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but a possible direct role of the virus in liver injury and its association with short-term outcomes are controversial. Therefore, we aimed to compare the pattern of abnormal liver tests in patients with SARS-CoV-2 with those of patients infected with influenza, a non-hepatotropic respiratory virus, and their association with worse outcomes during hospitalisation.

Methods

We performed a retrospective cohort study of 1,737 hospitalised patients (865 with influenza and 872 with SARS-CoV-2) in a tertiary medical centre. We defined abnormal liver tests as alanine transaminase or aspartate transaminase ≥40 IU/ml at any time-point during hospitalisation.

Results

Abnormal liver tests were mild to moderate in most patients regardless of infection type, but the majority of patients with influenza had a transaminase peak earlier during hospitalisation compared with patients with SARS-CoV-2. Abnormal liver tests correlated with markers of severe disease in either influenza or SARS-CoV-2 infections, and were associated with death, occurring mainly in patients with severe liver test abnormalities (>200 IU/L) (38.7% and 60% of patients with influenza or SARS-CoV-2, respectively). In multivariate analysis, controlling for age, sex, lymphopaenia, and C-reactive protein, liver test abnormalities remained significantly associated with death for influenza (odds ratio 4.344; 95% CI 2.218-8.508) and SARS-CoV-2 (odds ratio 3.898; 95% CI 2.203-6.896). These results were confirmed upon propensity score matching.

Conclusions

Abnormal liver tests during hospitalisation with SARS-CoV-2 or influenza infections are common, may differ in their time course, and reflect disease severity. They are associated with worse outcomes, mainly in patients with severe liver test abnormalities, regardless of infection type.

Lay summary

Coronavirus disease 2019 (COVID-19) is a serious global health pandemic, the causative agent of which is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Abnormal liver tests are common among SARS-CoV-2 infected patients and are often associated with worse outcomes. Herein, we compare the pattern of abnormal liver tests and their association with disease severity between 2 major non-hepatotropic respiratory viruses: SARS-CoV-2 and influenza. We show that abnormal liver tests are common in both infections, may slightly differ in their kinetics, and are associated with worse outcomes, especially in patients with severe liver test abnormalities. These results strongly suggest that abnormal liver tests in SARS-CoV-2 patients reflect disease severity, rather than a virus-mediated direct liver injury, and should be closely followed in admitted patients.

Comparative sequence analysis of SARS-CoV-2 suggests its high transmissibility and pathogenicity

Aim: Because the highly pathogenic SARS-CoV-2 is newly introduced to humans, we aimed to understand the unique features of its genome and proteins, crucial for high transmissibility and disease severity. Materials & methods: The available genome and protein sequences of SARS-CoV-2 with known human and nonhuman CoV were analyzed using multiple sequence alignment programs. Results: Our analysis revealed some unique mutations in SARS-CoV-2 spike, ORF1a/b, ORF3a/3b and ORF8. The most interesting ones were in the spike angiotensin-converting enzyme 2 receptor binding-motif and generation of a furin-like cleavage site as well as deletions of ORF3a ‘diacidic motif’ and the entire ORF3b. Conclusion: Our data suggest that SARS-CoV-2 has diverged from SARS-CoV-1 but is most close to bat-SL-CoV. Unique mutations in spike and ORF3a/b proteins strongly endorse its adaptive evolution, enhanced infectivity and severe pathogenesis in humans.

Implications of COVID-19 for the busy gastroenterologist

Coronavirus disease 2019 (COVID-19) is an infection caused by a novel coronavirus (SARS-CoV-2) originated in China in December 2020 and declared pandemic by WHO. This coronavirus mainly spreads through the respiratory tract and enters cells through angiotensin-converting enzyme 2 (ACE2). The clinical symptoms of COVID-19 patients include fever, cough, and fatigue. Gastrointestinal symptoms (diarrhea, anorexia, and vomiting) may be present in 50% of patients and may be associated with worst prognosis. Other risk factors are older age, male gender, and underlying chronic diseases. Mitigation measures are essential to reduce the number of people infected. Hospitals are a place of increased SARS-CoV-2 exposure. This has implications in the organization of healthcare services and specifically endoscopy departments. Patients and healthcare workers safety must be optimized in this new reality. Comprehension of COVID-19 gastrointestinal manifestations and implications of SARS-CoV-2 in the management of patients with gastrointestinal diseases, under or not immunosuppressant therapies, is essential. In this review, we summarized the latest research progress and major societies recommendations regarding the implications of COVID-19 in gastroenterology, namely the adaptations that gastroenterology/endoscopy departments and professionals must do in order to optimize the provided assistance, as well as the implications that this infection will have, in particularly vulnerable patients such as those with chronic liver disease and inflammatory bowel disease under or not immunosuppressant therapies.

Viral Nanoparticles: Cancer Vaccines and Immune Modulators

In the last decades, viruses have gained great interest in the field of immuno-oncology (I-O) for their ability of interacting both with the immune system and the tumour microenvironment. Those pathogens have naturally evolved and been evolutionary to specifically infect hosts, replicate, deliver their genome, and spread. These properties, initially considered a disadvantage, have been investigated and edited to turn viruses into precious allies for molecular biology serving as gene therapy vectors, adjuvants for the immune system, drug cargos, and, lately, anticancer therapeutics. As anticancer drug, one interesting option is viral engineering. Modification of either the viral genome or the outer shell of viruses can change infectivity and tissue targeting and add new functions to the viral particle. Remarkably, in the field of cancer virotherapy, scientists realized that a specific viral genomic depletion would turn the normal tropism of viruses to conditionally replicate in cancer cells only. This category of viruses, named 'Oncolytic viruses', have been investigated and used for cancer treatment in the past decades resulting in the approval of the first oncolytic virus, a herpes simplex virus expressing a stimulating factor, named T-Vec, in 2015. As such, oncolytic viruses achieved positive outcome but still are not able to completely eradicate the disease. This has brought the scientific community to edit those agents, adding to their ability to directly lysate cancer cells, few modifications to mainly boost their interaction with the immune system. Viruses experienced then a renaissance not only as infecting agent but as nanoparticle and cancer vaccines too. These strategies bring new life to the concept of using viruses as viral particles for therapeutic applications.

Impact of chronic liver disease upon admission on COVID-19 in-hospital mortality: Findings from COVOCA study

BACKGROUND

Italy has been the first Western country to be heavily affected by the spread of SARS-COV-2 infection and among the pioneers of the clinical management of pandemic. To improve the outcome, identification of patients at the highest risk seems mandatory.

OBJECTIVES

Aim of this study is to identify comorbidities and clinical conditions upon admission associated with in-hospital mortality in several COVID Centers in Campania Region (Italy).

METHODS

COVOCA is a multicentre retrospective observational cohort study, which involved 18 COVID Centers throughout Campania Region, Italy. Data were collected from patients who completed their hospitalization between March-June 2020. The endpoint was in-hospital mortality, assessed either from data at discharge or death certificate, whilst all exposure variables were collected at hospital admission.

RESULTS

Among 618 COVID-19 hospitalized patients included in the study, 143 in-hospital mortality events were recorded, with a cumulative incidence of about 23%. At multivariable logistic analysis, male sex (OR 2.63, 95%CI 1.42-4.90; p = 0.001), Chronic Liver Disease (OR 5.88, 95%CI 2.39-14.46; p<0.001) and malignancies (OR 2.62, 95%CI 1.21-5.68; p = 0.015) disclosed an independent association with a poor prognosis, Glasgow Coma Scale (GCS) and Respiratory Severity Scale allowed to identify at higher mortality risk. Sensitivity analysis further enhanced these findings.

CONCLUSION

Mortality of patients hospitalized for COVID-19 appears strongly affected by both clinical conditions on admission and comorbidities. Originally, we observed a very poor outcome in subjects with a chronic liver disease, alongside with an increase of hepatic damage.

Severe acute respiratory syndrome coronavirus-2 infection and the gut-liver axis

Patients affected by coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, manifest various gastrointestinal and hepatic abnormalities alongside respiratory disorders. The identification of this virus in the feces of more than 50% of infected individuals indicates the possibility of viral shedding and fecal-to-oral transmission. Preliminary reports have also identified alterations in the intestinal microbiota profile in infected individuals. Moreover, COVID-19 patients manifest various degrees of liver injury characterized by alterations in liver enzymes. Digestive symptoms and liver abnormalities correlate with disease severity, the incidence of critical outcomes and patient's recovery. However, the pathogenic mechanisms behind COVID-19-induced abnormalities in the gut-liver axis seem to be multifactorial in origin. This review compiles current knowledge sourced from preclinical and clinical research and summarizes gastrointestinal and hepatic dysfunctions observed following SARS-CoV-2 infection, and also explores the possible mechanisms generating abnormalities in the gut-liver axis. Furthermore, this review sheds light on possible therapeutic targets against these disorders.

COVID-19 and multiorgan failure: A narrative review on potential mechanisms

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) in December 2019 form Wuhan, China leads to coronavirus disease 2019 (COVID-19) pandemic. While the common cold symptoms are observed in mild cases, COVID-19 is accompanied by multiorgan failure in severe patients. The involvement of different organs in severe patients results in lengthening the hospitalization duration and increasing the mortality rate. In this review, we aimed to investigate the involvement of different organs in COVID-19 patients, particularly in severe cases. Also, we tried to define the potential underlying mechanisms of SARS-CoV2 induced multiorgan failure. The multi-organ dysfunction is characterized by acute lung failure, acute liver failure, acute kidney injury, cardiovascular disease, and as well as a wide spectrum of hematological abnormalities and neurological disorders. The most important mechanisms are related to the direct and indirect pathogenic features of SARS-CoV2. Although the presence of angiotensin-converting enzyme 2, a receptor of SARS-CoV2 in the lung, heart, kidney, testis, liver, lymphocytes, and nervous system was confirmed, there are controversial findings to about the observation of SARS-CoV2 RNA in these organs. Moreover, the organ failure may be induced by the cytokine storm, a result of increased levels of inflammatory mediators, endothelial dysfunction, coagulation abnormalities, and infiltration of inflammatory cells into the organs. Therefore, further investigations are needed to detect the exact mechanisms of pathogenesis. Since the involvement of several organs in COVID-19 patients is important for clinicians, increasing their knowledge may help to improve the outcomes and decrease the rate of mortality and morbidity.

Effect of SARS-CoV-2 coinfection was not apparent on the dynamics of chronic hepatitis B infection

In patients coinfected with SARS-CoV-2 and HBV, liver injury was common. However, the interactions between SARS-CoV-2 and HBV coinfection remained unknown. Sixty-seven COVID-19 patients from the previous cohort were enrolled and classified into 2 groups (7 with HBsAg+ and 60 with HBsAg-). The association of HBV- and SARS-CoV-2-related markers were analyzed. During the acute course of SARS-CoV-2 infection, markers of HBV replication did not extensively fluctuate during SARS-CoV-2 infection. Coinfection with HBV did not extend the viral shedding cycle or incubation periods of SARS-CoV-2. Effects of SARS-CoV-2 on the dynamics of chronic HBV infection seemed not apparent. SARS-CoV-2 infection would not be the source of HBV reactivation in these individuals.

Gastrointestinal predictors of severe COVID-19: systematic review and meta-analysis

BACKGROUND

COVID-19 pandemic has created a need to identify potential predictors of severe disease. We performed a systematic review and meta-analysis of gastrointestinal predictors of severe COVID-19.

METHODS

An extensive literature search was performed using PubMed, Embase, Web of Science and Cochrane. Odds ratio (OR) and mean difference (MD) were calculated for proportional and continuous outcomes using a random-effect model. For each outcome, a 95% confidence interval (CI) and P-value were generated.

RESULTS

A total of 83 studies (26912 patients, mean age 43.5±16.4 years, 48.2% female) were included. Gastrointestinal predictors of severe COVID-19 included the presence of diarrhea (OR 1.50, 95%CI 1.10-2.03; P=0.01), elevated serum aspartate aminotransferase (AST) (OR 4.00, 95%CI 3.02-5.28; P<0.001), and elevated serum alanine aminotransferase (ALT) (OR 2.54, 95%CI 1.91-3.37; P<0.001). Significantly higher levels of mean AST (MD 14.78 U/L, 95%CI 11.70-17.86 U/L; P<0.001), ALT (MD 11.87 U/L, 95%CI 9.23-14.52 U/L; P<0.001), and total bilirubin (MD 2.08 mmol/L, 95%CI 1.36-2.80 mmol/L; P<0.001) were observed in the severe COVID-19 group compared to non-severe COVID-19 group.

CONCLUSION

Gastrointestinal symptoms and biomarkers should be assessed early to recognize severe COVID-19.

Hepatocytes trap and silence coxsackieviruses, protecting against systemic disease in mice

Previous research suggests that hepatocytes catabolize chemical toxins but do not remove microbial agents, which are filtered out by other liver cells (Kupffer cells and endothelial cells). Here we show that, contrary to current understanding, hepatocytes trap and rapidly silence type B coxsackieviruses (CVBs). In genetically wildtype mice, this activity causes hepatocyte damage, which is alleviated in mice carrying a hepatocyte-specific deletion of the coxsackievirus-adenovirus receptor. However, in these mutant mice, there is a dramatic early rise in blood-borne virus, followed by accelerated systemic disease and increased mortality. Thus, wild type hepatocytes act similarly to a sponge for CVBs, protecting against systemic illness at the expense of their own survival. We speculate that hepatocytes may play a similar role in other viral infections as well, thereby explaining why hepatocytes have evolved their remarkable regenerative capacity. Our data also suggest that, in addition to their many other functions, hepatocytes might be considered an integral part of the innate immune system.

Kimura, Flynn and Whitton find that hepatocytes act as a sponge to trap viruses, but that doing so damages the liver cells. They show that, when mouse hepatocytes are altered to prevent trapping of circulating virus, the mice are more likely to develop systemic disease and die, providing strong evidence for an important overlooked function of hepatocytes.

A Case of Fulminant Liver Failure in a 24-Year-Old Man with Coinfection with Hepatitis B Virus and SARS-CoV-2

Patient: Male, 24-year-old

Final Diagnosis: Acute kidney injury • coagulopathy • liver failure • SARS-CoV-2

Symptoms: Cough • fever

Medication: —

Clinical Procedure: —

Specialty: Gastroenterology and Hepatology • Infectious Diseases

Tocilizumab and liver injury in patients with COVID-19

Current mortality rate in patients with COVID-19 disease is about 2%, whereas 5% of patients require admission to the intensive care unit. It is assumed that interleukin (IL)-6 may be involved in the pathogenesis of severe COVID-19 infections; therefore, in the absence of a specific antiviral therapy, some authors have suggested that tocilizumab - a drug used to block the signal transduction pathway of IL-6 - could have beneficial effects in the management of severe COVID-19 disease. However, mild-to-moderate elevation in transaminases and drug-induced liver injury have been observed in patients treated with tocilizumab. We present seven cases of patients with elevated liver enzymes [up to five times the upper limit of normal (ULN)] at baseline who received tocilizumab for life-threatening COVID-19 disease. All patients had no history of liver or pulmonary disease and were admitted for acute hypoxemic respiratory failure, dyspnea and fever due to COVID-19 bilateral pneumonia. IL-6 was available in six patients, and was significantly increased particularly in those with severe impairment of lung function. All patients received tocilizumab (8 mg/kg/day) for two consecutive days because of lack of improvement after hydroxychloroquine, azithromycin and lopinavir/ritonavir treatment. After tocilizumab administration, clinical condition rapidly improved and liver function test normalized within 3 weeks of treatment. Tocilizumab may be effective for the treatment of severe COVID-19 disease, even in patients with elevated liver function tests. Further studies are needed to evaluate the impact of tocilizumab use on liver function tests in patients with pre-existing chronic liver disease.

Liver injury in severe COVID-19 infection: current insights and challenges

INTRODUCTION

The outbreak of COVID-19 is a serious health threat worldwide. Different degrees of liver injury or liver dysfunctions have been reported in patients with COVID-19 infection. However, currently, it remains unclear to what extent liver diseases should be considered as significant risk factors for the severity and mortality of COVID-19. Moreover, the mechanisms involved in liver injury in severe COVID-19 infection are not yet well understood.

AREA COVERED

This review summarizes the current evidence on liver function abnormalities in COVID-19 patients and the effects of preexisting liver disease on the disease severity. This review also illustrates the possible underlying mechanisms linking COVID-19 to liver injury, as well as provides recommendations to prevent liver damage in COVID-19 infection.

EXPERT OPINION

The elevated levels of ALT, AST, GGT and bilirubin are common in more severe patients than non-severe or mild COVID-19 patients. Patients with preexisting medical conditions including chronic hepatic diseases are at higher risk for severe illness from COVID-19 infection. The drug's effects, possible viral inclusion in liver cells, systemic inflammation and hypoxia are potential causes of liver injury in severe COVID-19. Nevertheless, further studies are needed focusing on the preexisting hepatic diseases on prevention, treatment and outcome of COVID-19.

Arbones-Mainar J. SARS-CoV-2 Infection Induces a Dual Response in Liver Function Tests: Association with Mortality during Hospitalization

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with abnormal liver function tests. We hypothesized that early altered liver biochemistries at admission might have different clinical relevance than subsequent changes during hospitalization. A single-center retrospective study was conducted on 540 consecutive hospitalized patients, PCR-diagnosed with SARS-CoV-2. Liver test abnormalities were defined as the elevation of either gamma-glutamyltransferase (GGT), alanine aminotransferase (ALT), or aspartate aminotransferase (AST), above the upper limit of normality set by our laboratory. Linear mixed models (LMM) evaluated longitudinal associations, incorporating all available follow-up laboratory chemistries. By the end of the follow-up period, 502 patients (94.5%) were discharged (109 (20.5%) died). A total of 319 (64.3%) had at least one abnormal liver test result at admission. More prevalent were elevated AST (40.9%) and GGT (47.3%). Abnormalities were not associated with survival but with respiratory complications at admission. Conversely, LMM models adjusted for age and sex showed that longitudinal increases during hospitalization in ferritin, GGT, and alkaline phosphatase (ALP), as well as a decreased albumin levels, were associated with reduced survival. This dual pattern of liver damage might reconcile previous conflicting reports. GGT and ALP trajectories could be useful to determine who might need more surveillance and intensive care.

Incidence, pattern and severity of abnormal liver blood tests among hospitalised patients with SARS-COV2 (COVID-19) in South Wales

INTRODUCTION

SARS-CoV-2 (COVID-19) is a novel coronavirus that emerged in Wuhan, China in late 2019 and since become a global pandemic. As such, its clinical behaviour is a subject of much interest. Initial reports suggested a significant proportion of patients have abnormal liver blood tests. Gwent has experienced one of the highest incidences of COVID-19 infection in the UK, which itself has among the highest COVID-19 impacts worldwide.

METHOD

We set out to report the incidence, clinical pattern and severity of liver blood test abnormalities in hospitalised patients with confirmed COVID-19 in our institution over a 3-week period. Data on clinical outcomes such as admission to intensive therapy unit (ITU), hospital discharge and mortality were recorded.

RESULTS

318 hospitalised COVID-19 positive had liver blood tests available for analysis. Ninety-seven patients (31%) had one or more abnormal liver blood tests and were abnormal admission in 64%. Liver tests were predominantly cholestatic (72%) in contrast to other studies to date. Male gender and abnormal liver blood tests were associated with ITU admission.

CONCLUSIONS

Almost one-third of admissions with COVID-19 have abnormal LBTs which are typically mild and are associated with male gender. Importantly, we have identified that cholestatic patterns dominate but were not clearly associated with ITU admission or death.

Correlations of Clinical and Laboratory Characteristics of COVID-19: A Systematic Review and Meta-Analysis

(1) Background: The global threat of Coronavirus disease 2019 (COVID-19) continues. The diversity of clinical characteristics and progress are reported in many countries as the duration of the pandemic is prolonged. We aimed to perform a novel systematic review and meta-analysis focusing on findings about correlations between clinical characteristics and laboratory features of patients with COVID-19. (2) Methods: We analyzed cases of COVID-19 in different countries by searching PubMed, Embase, Web of Science databases and Google Scholar, from the early stage of the outbreak to late March. Clinical characteristics, laboratory findings, and treatment strategies were retrospectively reviewed for the analysis. (3) Results: Thirty-seven (n = 5196 participants) COVID-19-related studies were eligible for this systematic review and meta-analysis. Fever, cough and fatigue/myalgia were the most common symptoms of COVID-19, followed by some gastrointestinal symptoms which are also reported frequently. Laboratory markers of inflammation and infection including C-reactive protein (CRP) (65% (95% confidence interval (CI) 56–81%)) were elevated, while lymphocyte counts were decreased (63% (95% CI 47–78%)). Meta-analysis of treatment approaches indicated that three modalities of treatment were predominantly used in the majority of patients with a similar prevalence, including antiviral agents (79%), antibiotics (78%), and oxygen therapy (77%). Age was negatively correlated with number of lymphocytes, but positively correlated with dyspnea, number of white blood cells, neutrophils, and D-dimer. Chills had been proved to be positively correlated with chest tightness, lung abnormalities on computed tomography (CT) scans, neutrophil/lymphocyte/platelets count, D-dimer and CRP, cough was positively correlated with sputum production, and pulmonary abnormalities were positively correlated with CRP. White blood cell (WBC) count was also positively correlated with platelet counts, dyspnea, and neutrophil counts with the respective correlations of 0.668, 0.728, and 0.696. (4) Conclusions: This paper is the first systematic review and meta-analysis to reveal the relationship between various variables of clinical characteristics, symptoms and laboratory results with the largest number of papers and patients until now. In elderly patients, laboratory and clinical characteristics indicate a more severe disease course. Moreover, treatments such as antiviral agents, antibiotics, and oxygen therapy which are used in over three quarters of patients are also analyzed. The results will provide “evidence-based hope” on how to manage this unanticipated and overwhelming pandemic.

Hepatic consequences of COVID-19 infection. Lapping or biting?

The outbreak of coronavirus disease 2019 (COVID-19) starting last December in China placed emphasis on liver involvement during infection. This review discusses the underlying mechanisms linking COVID-19 to liver dysfunction, according to recent available information, while waiting further studies. The manifestations of liver damage are usually mild (moderately elevated serum aspartate aminotransferase activities), and generally asymptomatic. Few patients can still develop severe liver problems, and therapeutic options can be limited. Liver dysfunction may affect about one-third of the patients, with prevalence greater in men than women, and in elderly. Mechanisms of damage are complex and include direct cholangiocyte damage and other coexisting conditions such as the use of antiviral drugs, systemic inflammatory response, respiratory distress syndrome-induced hypoxia, sepsis, and multiple organ dysfunction. During new COVID-19 infections, liver injury may be observed. If liver involvement appears during COVID-19 infection, however, attention is required. This is particularly true if patients are older or have a pre-existing history of liver diseases. During COVID-19 infection, the onset of liver damage impairs the prognosis, and hospital stay is longer.

Review article: COVID-19 and liver disease-what we know on 1st May 2020

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative pathogen of coronavirus disease 2019 (COVID-19), became a global threat to human health. Liver impairment has been frequently reported as a common manifestation, although its clinical significance is still unclear, particularly in patients with underlying chronic liver disease (CLD).

AIMS

To summarise the changes in liver function tests during SARS-CoV-2 infection and the impact of COVID-19 in patients with underlying CLD.

METHODS

A literature review using online database PubMed was done using the search terms "SARS-CoV-2", "COVID-19", "liver", "cirrhosis" and "liver transplantation".

RESULTS

COVID-19 is frequently associated with different degrees of abnormal liver function tests, most notably transaminases, which are usually transitory and of mild degree. Available evidence suggests that liver injury may result from direct pathogenic effect by the virus, systemic inflammation or toxicity from commonly used drugs in this subset of patients. SARS-CoV-2 infection in children is associated with minimal or no increase in liver enzymes, thus the presence of abnormal liver function tests should trigger evaluation for underlying liver diseases. Although it seems that patients with CLD are not at greater risk for acquiring the infection, those with cirrhosis, hepatocellular carcinoma, non-alcoholic fatty liver disease, autoimmune liver diseases or liver transplant may have a greater risk for severe COVID-19.

CONCLUSIONS

Abnormal liver function tests during the course of COVID-19 are common, though clinically significant liver injury is rare. Further research is needed focusing on the effect of existing liver-related comorbidities on treatment and outcome of COVID-19.

Cytochrome P450-mediated drug interactions in COVID-19 patients: Current findings and possible mechanisms

At the end of 2019, the entire world has witnessed the birth of a new member of coronavirus family in Wuhan, China. Ever since, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has swiftly invaded every corner on the planet. By the end of April 2020, almost 3.5 million cases have been reported worldwide, with a death toll of about 250,000 deaths. It is currently well-recognized that patient’s immune response plays a pivotal role in the pathogenesis of Coronavirus Disease 2019 (COVID-19). This inflammatory element was evidenced by its elevated mediators that, in severe cases, reach their peak in a cytokine storm. Together with the reported markers of liver injury, such hyperinflammatory state may trigger significant derangements in hepatic cytochrome P450 metabolic machinery, and subsequent modulation of drug clearance that may result in unexpected therapeutic/toxic response. We hypothesize that COVID-19 patients are potentially vulnerable to a significant disease-drug interaction, and therefore, suitable dosing guidelines with therapeutic drug monitoring should be implemented to assure optimal clinical outcomes.

Liver injury in COVID-19: The current evidence

Patients with novel coronavirus disease 2019 (COVID-19) experience various degrees of liver function abnormalities. Liver injury requires extensive work-up and continuous surveillance and can be multifactorial and heterogeneous in nature. In the context of COVID-19, clinicians will have to determine whether liver injury is related to an underlying liver disease, drugs used for the treatment of COVID-19, direct effect of the virus, or a complicated disease course. Recent studies proposed several theories on potential mechanisms of liver injury in these patients. This review summarizes current evidence related to hepatobiliary complications in COVID-19, provides an overview of the available case series and critically elucidates the proposed mechanisms and provides recommendations for clinicians.

SARS-CoV-2 Infection and the Liver

A novel strain of coronoviridae (SARS-CoV-2) was reported in Wuhan China in December 2019. Initially, infection presented with a broad spectrum of symptoms which typically included muscle aches, fever, dry cough, and shortness of breath. SARS-CoV-2 enters cells via ACE2 receptors which are abundant throughout the respiratory tract. However, there is evidence that these receptors are abundant throughout the body, and just as abundant in cholangiocytes as alveolar cells, posing the question of possible direct liver injury. While liver enzymes and function tests do seem to be deranged in some patients, it is questionable if the injury is due to direct viral damage, drug-induced liver injury, hypoxia, or microthromboses. Likely, the injury is multifactoral, and management of infected patients with pre-existing liver disease should be taken into consideration. Ultimately, a vaccine is needed to aid in reducing cases of SARS-CoV-2 and providing immunity to the general population. However, while considering the types of vaccines available, safety concerns, particularly of RNA- or DNA-based vaccines, need to be addressed.

Respiratory and Nonrespiratory Diagnoses Associated With Influenza in Hospitalized Adults

IMPORTANCE

Seasonal influenza virus infection is a major cause of morbidity and mortality and may be associated with respiratory and nonrespiratory diagnoses.

OBJECTIVE

To examine the respiratory and nonrespiratory diagnoses reported for adults hospitalized with laboratory-confirmed influenza between 2010 and 2018 in the United States.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study used data from the US Influenza Hospitalization Surveillance Network (FluSurv-NET) from October 1 through April 30 of the 2010-2011 through 2017-2018 influenza seasons. FluSurv-NET is a population-based, multicenter surveillance network with a catchment area that represents approximately 9% of the US population. Patients are identified by practitioner-ordered influenza testing. Adults (aged ≥18 years) hospitalized with laboratory-confirmed influenza were included in the study.

EXPOSURES

FluSurv-NET defines laboratory-confirmed influenza as a positive influenza test result by rapid antigen assay, reverse transcription-polymerase chain reaction, direct or indirect fluorescent staining, or viral culture.

MAIN OUTCOMES AND MEASURES

Acute respiratory or nonrespiratory diagnoses were defined using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) and International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10) discharge diagnosis codes. The analysis included calculation of the frequency of acute respiratory and nonrespiratory diagnoses with a descriptive analysis of patient demographic characteristics, underlying medical conditions, and in-hospital outcomes by respiratory and nonrespiratory diagnoses.

RESULTS

Of 89 999 adult patients hospitalized with laboratory-confirmed influenza, 76 649 (median age, 69 years; interquartile range, 55-82 years; 55% female) had full medical record abstraction and at least 1 ICD code for an acute diagnosis. In this study, 94.9% of patients had a respiratory diagnosis and 46.5% had a nonrespiratory diagnosis, including 5.1% with only nonrespiratory diagnoses. Pneumonia (36.3%), sepsis (23.3%), and acute kidney injury (20.2%) were the most common acute diagnoses. Fewer patients with only nonrespiratory diagnoses received antiviral therapy for influenza compared with those with respiratory diagnoses (81.4% vs 88.9%; P < .001).

CONCLUSIONS AND RELEVANCE

Nonrespiratory diagnoses occurred frequently among adults hospitalized with influenza, further contributing to the burden of infection in the United States. The findings suggest that during the influenza season, practitioners should consider influenza in their differential diagnosis for patients who present to the hospital with less frequently recognized manifestations and initiate early antiviral treatment for patients with suspected or confirmed infection.

The hepatic lipidome: From basic science to clinical translation

The liver is the key organ involved in lipid metabolism and transport. Excessive lipid accumulation due to dysregulated lipid metabolism predisposes the liver to steatosis, cirrhosis, and hepatocellular carcinoma. Lipids are generally compartmentalized in specialized organelles called lipid droplets that enable cells to store and release lipids in a regulated manner. However, during flux-in and flux-out of droplets, lipids are converted into toxic species leading to lipid-mediated liver damage. Lipids are categorized into 'toxic' or 'healthy' lipids that are involved in liver disease pathogenesis or resolution, respectively. Lipidomic analysis have revealed unique lipid signature that correlates with the disease progression therefore being used for disease diagnosis. In this comprehensive review, we provide an overview on hepatic lipid homeostasis, lipid compartmentalization mechanisms and lipidomic profiles in different liver diseases. We further discuss promising therapeutics targeting the hepatic lipidome including pro-resolving lipids, liposomes, and small-molecule inhibitors for the treatment of liver diseases.

Type I Interferon Signaling Disrupts the Hepatic Urea Cycle and Alters Systemic Metabolism to Suppress T Cell Function

Infections induce complex host responses linked to antiviral defense, inflammation, and tissue damage and repair. We hypothesized that the liver, as a central metabolic hub, may orchestrate systemic metabolic changes during infection. We infected mice with chronic lymphocytic choriomeningitis virus (LCMV), performed RNA sequencing and proteomics of liver tissue, and integrated these data with serum metabolomics at different infection phases. Widespread reprogramming of liver metabolism occurred early after infection, correlating with type I interferon (IFN-I) responses. Viral infection induced metabolic alterations of the liver that depended on the interferon alpha/beta receptor (IFNAR1). Hepatocyte-intrinsic IFNAR1 repressed the transcription of metabolic genes, including Otc and Ass1, which encode urea cycle enzymes. This led to decreased arginine and increased ornithine concentrations in the circulation, resulting in suppressed virus-specific CD8+ T cell responses and ameliorated liver pathology. These findings establish IFN-I-induced modulation of hepatic metabolism and the urea cycle as an endogenous mechanism of immunoregulation. VIDEO ABSTRACT.

Influenza A virus infection induces liver injury in mice

Respiratory infections such as SARS-CoV in humans are often accompanied by mild and self-limiting hepatitis. As a respiratory disease, influenza A virus (IAV) infection can lead to hepatitis, but the mechanism remains unclear. This study aimed to investigate the occurrence of hepatitis by establishing a model for infected mice for three different subtypes of respiratory IAVs (H1N1, H5N1, and H7N2). Histological analysis was performed, and results showed increase serum aminotransferase (ALT and AST) levels and evident liver injury on days 3 and 7, especially on day 5 post infection. Immunohistochemistry (IHC) results indicated a wide distribution of IAV's positive signals in the liver of infected mice. Real-time PCR results further revealed a similar viral titer to IHC that presented a remarkedly positive correlation with histology injury. All these data showed that the mouse model suitably contributed valuable information about the mechanism underlying the occurrence of hepatitis induced by respiratory influenza virus.

The potential protective effect of two actinomycete extracts against carbon tetrachloride-induced hepatotoxicity in rats

The aim of this study was to investigate the potential protective effect of two extracts derived from two soil actinomycete strains, designated S19 and G30, against CCl4-induced hepatotoxicity in male rats. Sixty-four male rats were divided into four groups of 16 rats per group. The first group was a control group given corn oil and the nutritive medium which is composed of a mixture of the two used media. The second group received CCl₄ only, the third group was administered CCl₄ and the extract S19, and the fourth group was administered CCl₄ and the extract G30. The results were taken after a treatment period of 8 weeks. Our data demonstrated that the two actinomycete extracts significantly (P < 0.01) lowered the CCl₄-induced elevation of serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) after 8 weeks of treatment. The extract S19 had no effect on serum lactate dehydrogenase (LDH) and total bilirubin, whereas the extract G30 significantly decreased (P < 0.01) the elevated levels of these parameters in the serum, especially after 4 weeks of treatment. The levels of hepatic glutathione (GSH), glutathione peroxidase (GSH-Px), peroxidase (Px), catalase (CAT), and superoxide dismutase (SOD) significantly increased (P < 0.01), while those of malondialdehyde (MDA) markedly decreased in rats treated with the two extracts. Furthermore, histopathological lesions in the liver, including necrosis, inflammatory cell infiltration, hydropic degeneration, and congestion of the central vein, were partially reversed by treatment with the two microbial extracts. Our results provided evidence for the protective effect of the two used actinomycete extracts against CCl₄-induced liver damage occurred through the reduction of oxidative stress and improvement of antioxidant defense markers.

A/H1N1/09 Influenza is Associated With High Mortality in Liver Cirrhosis

BACKGROUND/AIMS

A/H1N1/09 influenza is associated with a high risk of complications in patients with chronic diseases. In view of patients with cirrhosis being recognized as another high-risk group for influenza morbidity and mortality, we report a cluster of suspected A/H1N1/09 infection in 110 patients admitted to a hepatology intensive care unit.

METHODS

The pattern of spread, clinical outcome, and respiratory parameters of A/H1N1/09 of 22 positive cirrhotic patients were compared with those from a control group of 88 patients with chronic liver disease (CLD) with influenza-like pneumonia who tested negative for A/H1N1/09.

RESULTS

A/H1N1/09 infection was confirmed in 22 (20%) patients. Eighteen of 22 (81.8%) CLD patients with A/H1N1/09 died of pneumonia and acute respiratory distress syndrome despite timely antiviral treatment. In contrast, only 35 (40%)of the control group of cirrhotic patients without A/H1N1/09 died. On univariate analysis, age > 45 years [OR 1.3; 95% CI 1.1-5.7, (P = 0.054)], encephalopathy > grade 2 [OR 5.4; 95% CI 2.8-12.3, (P = 0.042)], serum bilirubin >8 mg/dl [OR 2.1; 95% CI 1.8-12.3, (P = 0.052)], serum creatinine >1.8 mg/dl [OR 2.8; 95% CI 1.9-9.2, (P = 0.042)], PaO₂/FiO₂ ratio <200 [OR 4.5; 95% CI 3.1-18.5, (P = 0.026)] and INR > 2.5 [OR 2.2; 95% CI 1.8-6.7, (P = 0.032)] were risk factors for mortality at presentation. However, on multivariate analysis only PaO₂/FiO₂ ratio <200 and serum creatinine >1.8 mg/dl remained predictors of mortality. Secondary infections, whether fungal or bacterial, were noted to be independent risk factors for disease severity in patients with cirrhosis.

CONCLUSION

Early detection and referral, and early antiviral treatment with a strict control of nosocomial spread is essential in patients with cirrhosis during epidemic influenza.

Pulmonary influenza A virus infection leads to suppression of the innate immune response to dermal injury

The innate immune system is responsible for many important functions in the body including responding to infection, clearing cancerous cells, healing wounds, and removing foreign substances. Although many of these functions happen simultaneously in life, most laboratory studies of the innate immune response focus on one activity. How the innate immune system responds to concurrent insults in different parts of the body is not well understood. This study explores the impact of a lung infection on the cutaneous wound healing process. We used two complimentary models of injury: the excisional tail wound and subcutaneous implantation of polyvinyl alcohol (PVA) sponges. These models allow for assessment of the rate of closure and measurement of cellular and cytokine responses during acute wound healing, respectively. When mice with these healing wounds were infected with influenza A virus (IAV) in the lung there was a delay in wound healing. The viral lung infection suppressed the innate immune response in a healing wound, including cellular infiltrate, chemokines, growth factors, and cytokines. However, there was not a global immune suppression as there was an increase in inflammation systemically in mice with both infection and healing wounds compared to mice with only wounds or IAV infection. In addition, the lung immune response was largely unaffected indicating that responding to a lung infection is prioritized over a healing wound. This study introduces the concept of immune triage, in that when faced with multiple insults the immune system prioritizes responses. This paradigm likely applies to many situations that involve the innate immune system, and understanding how the innate immune system handles multiple insults is essential to understanding how it can efficiently clear pathogens while responding to other inflammatory events.

In a natural setting, the innate immune system is frequently faced with multiple insults, against which it must mount overlapping inflammatory responses. We are interested in how the innate immune system deals with multiple, simultaneously occurring inflammatory insults, and if the response to one will take priority. For example, the innate immune system is essential in mediating both the early control of pathogen replication in infected tissue and in the early stages of wound healing. Pulmonary infections occur frequently in injured patient populations; therefore, we set out to determine the impact of a respiratory infection on a healing wound. To examine this, mice with healing dermal wounds were infected with influenza A virus (IAV), a common cause of viral pneumonia. We found that the innate immune response to the lung infection took priority at the expense of the healing wound, in that the initial control of viral replication in the lung was not impacted, while the wound healing response was suppressed. Very little work has been done examining how the immune response can respond to overlapping inflammatory insults. Our work shows that not all immune responses are created equal, and that the cells of the innate immune system are preferentially routed towards fighting a lung infection rather than the healing dermal wound. This apparent prioritization of the innate immune response opens up a new direction of study. It is relevant to many fields where competing insults may alter the disease state.

Sero-prevalence of hepatitis B infection among blood donors in a secondary care hospital, Ghana (2014): a retrospective analysis

BACKGROUND

The prevalence of transfusion associated hepatitis B virus infection varies across different geographical populations. Establishing the sero-prevalence of the disease is important to informing the direction of preventive and control strategies. We sought to estimate the sero-prevalence of hepatitis B surface antigen among blood donors in Ho Municipal Hospital, Ghana.

METHODS

This was a retrospective study which involved reviewing of blood donation records for the year 2014 in Ho Municipal Hospital. The records were analysed to determine the prevalence of hepatitis B virus among blood donors. Data analysis was done using STATA statistical package.

RESULTS

A total of 576 blood donors were screened in 2014, out of which 520 (90%) were males and the rest females. The overall sero-prevalence of hepatitis B virus was 7.5% (95% CI 5.6-9.9%). The prevalence was highest (8.9%; 95% CI 5.6-14.0) among donors between 30 and 39 years old and among females (14.3%; 95% CI 7.4-25.7). Females were about 2.5 times more likely to be HBsAg positive compared with males (p < 0.05).

CONCLUSIONS

The findings suggest that the study region is of intermediate to high endemicity with hepatitis B infection. Generally, females are more likely to be HBsAg positive than males. Planning more extensive screening and vaccination campaigns and educational programmes would help reduce the transmission of the infection among the general population.

The liver is a metabolic and immunologic organ: A reconsideration of metabolic decompensation due to infection in inborn errors of metabolism (IEM)

Metabolic decompensation in inborn errors of metabolism (IEM) is characterized by a rapid deterioration in metabolic status leading to life-threatening biochemical perturbations (e.g. hypoglycemia, hyperammonemia, acidosis, organ failure). Infection is the major cause of metabolic decompensation in patients with IEM. We hypothesized that activation of the immune system during infection leads to further perturbations in end-organ metabolism resulting in increased morbidity. To address this, we established model systems of metabolic decompensation due to infection. Using these systems, we have described the pathologic mechanisms of metabolic decompensation as well as changes in hepatic metabolic reserve associated with infection. First and foremost, our studies have demonstrated that the liver experiences a significant local innate immune response during influenza infection that modulates hepatic metabolism. Based on these findings, we are the first to suggest that the role of the liver as a metabolic and immunologic organ is central in the pathophysiology of metabolic decompensation due to infection in IEM. The dual function of the liver as a major metabolic regulator and a lymphoid organ responsible for immunosurveillance places this organ at risk for hepatotoxicity. Mobilization of hepatic reserve and the regenerative capacity of a healthy liver compensates for this calculated risk. However, activation of the hepatic innate immune system may be deleterious in IEM. Based on this assertion, strategies aimed at modulating the innate immune response may be a viable target for intervention in the treatment of hepatic metabolic decompensation.

JNK signaling is required for the MIP‑1α‑associated regulation of Kupffer cells in the heat stroke response

Severe heat stroke (HS) consists of extreme hyperthermia with thermoregulatory failure, leading to high morbidity and mortality. Liver injury is a complication of HS that is associated with inflammatory responses and Kupffer cells (KCs), which are resident macrophages in the liver that serve as a major source of inflammatory cytokines; however, the association and the underlying mechanisms of KC functions in HS-induced endotoxemia and inflammation require an improved understanding. The important chemokine macrophage inflammatory protein-1α (MIP-1α) increases inflammatory responses and the secretion of inflammatory molecules from KCs, including tumor necrosis factor-α, interleukin (IL)-1β and IL-6. In addition, the activation of c-Jun N-terminal kinase (JNK) signaling is responsible for the development of liver inflammation. Therefore, HS animal and cell models were constructed in order to investigate the pathways involved in the HS-induced dysfunction of KCs. The results of the present study suggest that JNK may be involved in the MIP-1α-associated pathogenesis of KCs in HS injury.

Viral Hepatitis: Other Viral Hepatides

Non-hepatotropic viruses cause acute hepatitis and/or acute liver failure, without causing any chronic damage to the liver. These viruses do not primarily target the liver. These viruses include the herpes viruses (Epstein-Barr virus, cytomegalovirus, and herpes simplex virus), parvovirus, adenovirus, influenza, and severe acute respiratory syndrome (SARS)-associated coronavirus.

The risk of acquiring infection from any of the non-hepatotropic viruses is specific to each virus. Infection with the herpesviruses is ubiquitous, with clinically significant hepatitis being less common. Considerations for determining the risk of hepatitis from non-hepatotropic viruses include prior exposure (risk of reactivation), host immune status (increase severity in immunosuppressed), and duration of infection in the contact.

Diagnosis is made with a combination of serology, polymerase chain reaction, or liver biopsy. Treatment is supportive in the majority. In certain clinical scenarios, such as cytomegalovirus infection in transplant patients, and acute liver failure from herpes simplex virus, specific antiviral therapy is warranted.

Prospects for Adult Stem Cells in the Treatment of Liver Diseases

Hepatocytes constitute the main bulk of the liver and perform several essential functions. After injury, the hepatocytes have a remarkable capacity to regenerate and restore functionality. However, in some cases, the endogenous hepatocytes cannot replicate or restore the function, and liver transplantation, which is not exempt of complications, is required. Stem cells offer in theory the possibility of generating unlimited supply of hepatocytes in vitro due to their capacity to self-renew and differentiate when given the right cues. Stem cells isolated from an array of tissues have been investigated for their capacity to differentiate into hepatocyte-like cells in vitro and are employed in rescue experiments in vivo. Adult stem cells have gained in attractiveness over embryonic stem cells for liver cell therapy due to their origin, multipotentiality, and the possibility of autologous transplantation. This review deals with the promise and limitations of adult stem cells in clinically restoring liver functionality.

Inhibitor-Based Therapeutics for Treatment of Viral Hepatitis

Viral hepatitis remains a significant worldwide threat, in spite of the availability of several successful therapeutic and vaccination strategies. Complications associated with acute and chronic infections, such as liver failure, cirrhosis and hepatocellular carcinoma, are the cause of considerable morbidity and mortality. Given the significant burden on the healthcare system caused by viral hepatitis, it is essential that novel, more effective therapeutics be developed. The present review attempts to summarize the current treatments against viral hepatitis, and provides an outline for upcoming, promising new therapeutics. Development of novel therapeutics requires an understanding of the viral life cycles and viral effectors in molecular detail. As such, this review also discusses virally-encoded effectors, found to be essential for virus survival and replication in the host milieu, which may be utilized as potential candidates for development of alternative therapies in the future.