Liver Injury as a Surrogate for Inflammation and Predictor of Outcomes in COVID-19

COVID-19-related liver injury: Mechanisms, diagnosis, management; its impact on pre-existing conditions, cancer and liver transplant: A comprehensive review

AIMS

This review explores the mechanisms, diagnostic approaches, and management strategies for COVID-19-induced liver injury, with a focus on its impact on patients with pre-existing liver conditions, liver cancer, and those undergoing liver transplantation.

MATERIALS AND METHODS

A comprehensive literature review included studies on clinical manifestations of liver injury due to COVID-19. Key areas examined were direct viral effects, drug-induced liver injury, cytokine storms, and impacts on individuals with chronic liver diseases, liver transplants, and the role of vaccination. Data were collected from clinical trials, observational studies, case reports, and review literature.

KEY FINDINGS

COVID-19 can cause a spectrum of liver injuries, from mild enzyme elevations to severe hepatic dysfunction. Injury mechanisms include direct viral invasion, immune response alterations, drug toxicity, and hypoxia-reperfusion injury. Patients with chronic liver conditions (such as alcohol-related liver disease, nonalcoholic fatty liver disease, cirrhosis, and hepatocellular carcinoma) face increased risks of severe outcomes. The pandemic has worsened pre-existing liver conditions, disrupted cancer treatments, and complicated liver transplantation. Vaccination remains crucial for reducing severe disease, particularly in chronic liver patients and transplant recipients. Telemedicine has been beneficial in managing patients and reducing cross-infection risks.

SIGNIFICANCE

This review discusses the importance of improved diagnostic methods and management strategies for liver injury caused by COVID-19. It emphasizes the need for close monitoring and customized treatment for high-risk groups, advocating for future research to explore long-term effects, novel therapies, and evidence-based approaches to improve liver health during and after the pandemic.

Association between Body Mass Index and Serum Uric Acid: mediation analysis involving liver enzymes indicators

BACKGROUND

Numerous studies have indicated a growing prevalence of hyperuricemia. Elevated levels of serum uric acid (SUA) have been established as influential factors in conditions such as obesity, metabolic syndrome, diabetes mellitus, gout, and cardiovascular disease. Overweight and obesity are closely related to an increase in SUA. Our objective is to demonstrate the mediating role of liver enzyme in the correlation between body mass index (BMI) and SUA.

METHODS

A total of 5925 adults aged 18 to 65 were included in this cross-sectional study. Logistic regression and mediation analysis were used to investigate the relationship between BMI and hyperuricemia as well as liver enzyme levels. Standard methods were used to determine the biochemical indexes, including SUA, liver enzymes, and blood lipids in the collected samples.

RESULTS

The study revealed that the prevalence of hyperuricemia was 28.0%. Furthermore, the prevalence of overweight and obesity was as high as 48.5%, with 70.7% of this subgroup presenting with hyperuricemia. There was a positive correlation between BMI and hyperuricemia, and elevated levels of liver enzymes (ALT, AST, GGT) were associated with a higher risk of hyperuricemia. The study also observed a positive correlation between BMI and liver enzymes (ALT, AST, GGT). The study findings suggested that ALT, AST, and GGT played significant mediating roles in the relationship between BMI and SUA. Specifically, the unadjusted model revealed that ALT and GGT accounted for 22.12% and 18.13% of the mediation effects, respectively.

CONCLUSIONS

The study found that BMI is associated with hyperuricemia, where liver enzyme abnormalities may have a mediating role. It is suggested that being overweight or obese may affect liver enzyme levels, leading to increased SUA levels. Controlling weight and liver enzyme levels may help prevent and treat hyperuricemia.

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

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

COVID-19 associated liver injury: An updated review on the mechanisms and management of risk groups

Coronavirus disease 2019 (COVID-19) has been associated with various liver injury cases worldwide. To date, the prevalence, mechanism, clinical manifestations, diagnosis, and outcomes of COVID-19-induced liver injury in various at-risk groups are not well defined. Liver injury may arise in the prevention and treatment of COVID-19 from direct causes such as viral infection and indirect causes such as systemic inflammation, hypoxic changes, and drugs that exacerbate any pre-existing liver disease. Studies have found that patients with underlying liver disease are at higher risk of COVID-19-induced liver injury. Certain condition of cardiopulmonary and metabolic diseases and vulnerable stages in lifespan may also involve in the development of COVID-19-induced liver injury. This review summarized studies of COVID-19-induced liver injury in different at-risk groups regarding their clinical characteristics, parameters, and correlations of the severity with these indicators and signs as well as potential treatment suggestions, to increase attention to physiological and pathological conditions and continue liver function monitoring as they can help in strengthening early supportive treatment and reducing the incidence of adverse outcomes.

Meta-analysis of liver injury in patients with COVID-19

BACKGROUND

The coronavirus disease 2019 (COVID-19) is a major public health problem threatening human health. It can lead to multiple system complications, among which liver damage is also a common complication of COVID-19. The pathogenesis of liver injury is complex and involves the interaction of multiple factors. This study aims to investigate the incidence and risk factors of liver injury in COVID-19 patients and analyze the impact of liver injury on clinical prognosis of patients, so as to provide corresponding basis for clinical diagnosis and treatment.

METHODS

PubMed and Cochrane Library were searched in computer to collect original studies on liver injury cases, laboratory indicators and clinical outcomes in COVID-19 patients. Articles were screened according to inclusion and exclusion criteria, and data were meta-analyzed using Stata12.0 software.

RESULTS

A total of 49 studies, including 23,611 patients with COVID-19, had a prevalence of liver injury of 39.63%. Subgroup analysis found that patients in the Americas had the highest incidence of liver injury at 43.7% and lowest in Africa (25.99%). The vast majority of liver injury is manifested by aminotransferase or bilirubin levels greater than 1 times the upper limit of normal (49.16%). The older the age, the male, the associated chronic liver disease, and the higher the levels of white blood cells, neutrophils, and C-reactive protein, the higher the risk of liver injury. The use of hormones, hydroxychloroquine, and tocilizumab increases the risk of liver injury. Patients with concurrent liver injury have longer hospital stays, are more likely to progress to severe cases, and have a higher risk of death than patients without liver injury.

CONCLUSION

The incidence of liver injury in COVID-19 patients was high, affected by age, gender, chronic liver disease, inflammatory state and medication, and patients with liver injury were hospitalized longer and were more likely to have a poor prognosis. Therefore, clinical attention should be paid to early intervention.

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

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

COVID-19-Associated Liver Injury

This review analyzes data regarding liver injury associated with COVID-19 infection. We discuss reported effects on the liver from both COVID-19 and COVID-19 treatment as well as pathophysiology, review the potential role of drug-induced liver injury as an etiology of COVID-19-associated liver injury, and touch on other reports of significant outcomes including COVID-19 cholangiopathy and autoimmune hepatitis. Finally, we review the implications of COVID-19 infection in liver transplant recipients.

Changing Features of Liver Injury in COVID-19 Patients: Impact of Infection with the SARS-CoV-2 Delta (B.1.617.2) Variants

BACKGROUND

There is growing evidence that abnormal liver function tests (LFTs) are common in patients with coronavirus disease 2019 (COVID-19). However, it is not known whether viral involvement in the liver differs according to the strain. We investigated the impact on liver injury in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta (B.1.617.2) variants.

MATERIALS AND METHODS

We conducted a single-center, retrospective cohort study, including 372 patients admitted during the pre-Delta period (PDP: between February 1 and November 30, 2020) and 137 patients admitted during the Delta period (DP: between August 1 and August 31, 2021). Initial liver injury was defined as alanine aminotransferase (ALT) or aspartate aminotransferase (AST) levels ≥3 × the upper limit of normal (ULN) or alkaline phosphatase (ALP) or total bilirubin ≥2 × the ULN within 3 days from admission.

RESULTS

Of 509 patients with COVID-19 included in our study, 38 (7.5%) patients had initial liver injury. The DP group had a significantly higher rate of initial liver injury than the PDP group (PDP: 5.9% vs. DP: 11.7%, P = 0.028). The DP group (adjusted odds ratio [aOR]: 2.737, 95% confidence interval [CI]: 1.322 - 5.666) was independently associated with initial liver injury. During hospitalization, 160 (31.4%) patients had severe COVID-19. The DP group and initial liver injury had higher odds of progressing to severe COVID-19 (aOR: 2.664, 95% CI: 1.526 - 4.648, and aOR: 4.409, 95% CI: 1.816 - 10.707, respectively). The mediation analysis suggested that initial liver injury mediates the relationship between SARS-CoV-2 Delta variant infection and severe COVID-19 (unstandardized beta coefficient = 0.980, Standard error = 0.284, P = 0.001).

CONCLUSION

Initial liver injury is more common in COVID-19 patients with Delta variants. Also, Delta variants and initial liver injury are associated with poor clinical outcomes.

COVID-19 associated liver injury: A general review with special consideration of pregnancy and obstetric outcomes

Liver injury is an increasingly recognized extra-pulmonary manifestation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Coronavirus disease 2019 (COVID-19) associated liver injury (COVALI) is a clinical syndrome encompassing all patients with biochemical liver injury identified in the setting of SARS-CoV-2 infection. Despite profound clinical implications, its pathophysiology is poorly understood. Unfortunately, most information on COVALI is derived from the general population and may not be applicable to individuals under-represented in research, including pregnant individuals. This manuscript reviews: Clinical features of COVALI, leading theories of COVALI, and existing literature on COVALI during pregnancy, a topic not widely explored in the literature. Ultimately, we synthesized data from the general and perinatal populations that demonstrates COVALI to be a hepatocellular transaminitis that is likely induced by systemic inflammation and that is strongly associated with disease severity and poorer clinical outcome, and offered perspective on approaching transaminitis in the potentially COVID-19 positive patient in the obstetric setting.

Effect of COVID-19 on Serum Activity of Liver Enzymes: Is This Associated with Severity and Mortality Rate?

Introduction Coronavirus disease 2019 (COVID-19) is a viral infection caused by a novel coronavirus known as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease raises an enormous public health challenge for the international community. Liver enzymes have been reported to be frequently elevated in hospitalized patients with severe COVID-19 disease.

Materials and Methods This article is a narrative review of abnormal liver tests and liver injury as a manifestation of progression to severe pneumonia. We collected data from the PubMed database (National Library of Medicine, Bethesda, Maryland, United States). We used the search term “abnormal liver test” and relevant records were measured. The review article was organized thematically.

Results This narrative review aims to summarize the available clinical data on abnormal liver enzymes in coronavirus infection and its association with the risk of mortality, severer pneumonia, and systemic inflammation. Some clinical studies refer to abnormal liver tests and liver injury as a manifestation of progression to severe pneumonia. Recent research verified the relationship between hepatic liver enzyme activities and liver damage in patients with COVID-19, which suggested that it might reflect the infection severity and the mortality risk. Thus, this review investigated the correlation between liver serum enzymes level and the severity of COVID-19 patients, by reviewing investigating the relationship between the illness severity in COVID-19 patients with abnormal liver tests, liver pathology, and markers of inflammation.

Conclusion In the current pandemic of SARS-CoV-2, abnormalities of liver enzyme tests were commonly observed in patients with COVID-19. However, because of multiorgan damages that observed in COVID-19 patients, various issues should be considered such as the pathology and pathophysiology of the liver tissue, especially on the activation process of the immune response and cytokine storm to prevent the severity of the disease.

The prevalence, predictors and outcomes of acute liver injury among patients with COVID-19: A systematic review and meta-analysis

The data on the predictors and prognosis of acute liver injury (ALI) among patients in coronavirus disease 2019 (COVID-19) patients are limited. The aim of this study was to determine the prevalence, predictors and outcomes of ALI among patients with COVID-19. A systematic review was conducted up to 10 June 2021. The relevant papers were searched from PubMed, Embase, Cochrane and Web of Science, and the data were analysed using a Z test. A total of 1331 papers were identified and 16 papers consisting of 1254 COVID-19 with ALI and 4999 COVID-19 without ALI were analysed. The cumulative prevalence of ALI among patients with COVID-19 was 22.8%. Male and having low lymphocyte levels were more likely to be associated with ALI compared with female and having higher lymphocyte level, odds ratio (OR): 2.70; 95% confidence interval (CI): 2.03, 3.60 and mean difference (MD) -125; 95% CI: -207, -43, respectively. COVID-19 patients with ALI had higher risk of developing severe COVID-19 compared with those without ALI (OR: 3.61; 95% CI: 2.60, 5.02). Our findings may serve as the additional evaluation for the management of ALI in COVID-19 patients.

Serum ferritin as a predictive biomarker in COVID-19. A systematic review, meta-analysis and meta-regression analysis

Ferritin is a known inflammatory biomarker in COVID-19. However, many factors and co-morbidities can confound the level of serum ferritin. This current metaanalysis evaluates serum ferritin level in different severity levels in COVID-19. Studies evaluating serum ferritin level in different clinical contexts (COVID-19 vs. control, mild to moderate vs. severe to critical, non-survivor vs. survivor, organ involvement, ICU and mechanical ventilation requirement) were included (total 9 literature databases searched). Metaanalysis and metaregression was carried out using metaphor "R" package. Compared to control (COVID-19 negative), higher ferritin levels were found among the COVID-19 patients [SMD -0.889 (95% C.I. -1.201, -0.577), I2 = 85%]. Severe to critical COVID-19 patients showed higher ferritin levels compared to mild to moderate COVID-19 patients [SMD 0.882 (0.738, 1.026), I2 = 85%]. In meta-regression, high heterogeneity was observed could be attributed to difference in "mean age", and "percentage of population with concomitant co-morbidities". Non-survivors had higher serum ferritin level compared to survivors [SMD 0.992 (0.672, 1.172), I2 = 92.33%]. In meta-regression, high heterogeneity observed could be attributed to difference in "mean age" and "percentage of male sex". Patients requiring ICU [SMD 0.674 (0.515 to 0.833), I2 = 80%] and mechanical ventilation [SMD 0.430 (0.258, 0.602), I2 = 32%] had higher serum ferritin levels compared to those who didn't. To conclude, serum ferritin level may serve as an important biomarker which can aid in COVID-19 management. However, presence of other co-morbid conditions/confounders warrants cautious interpretation.

Association of Statins and 28-Day Mortality Rates in Patients Hospitalized With Severe Acute Respiratory Syndrome Coronavirus 2 Infection

BACKGROUND

Statins may be protective in severe acute respiratory syndrome coronavirus 2 SARS-CoV-2 infection. The aim of the current study was to evaluate the effect of in-hospital statin use on 28-day mortality rates and intensive care unit (ICU) admission among patients with SARS-CoV-2, stratified into 4 groups: those who used statins before hospitalization (treatment continued or discontinued in the hospital) and those who did not (treatment newly initiated in the hospital or never initiated).

METHODS

In a cohort study of 1179 patients with SARS-CoV-2, record review was used to assess demographics, laboratory measurements, comorbid conditions, and time from admission to death, ICU admission, or discharge. Using marginal structural Cox models, we estimated hazard ratios (HRs) for death and ICU admission.

RESULTS

Among 1179 patients, 676 (57%) were male, 443 (37%) were >65 years old, and 493 (46%) had a body mass index ≥30 (calculated as weight in kilograms divided by height in meters squared). Inpatient statin use reduced the hazard of death (HR, 0.566; P=.008). This association held among patients who did and those who did not use statins before hospitalization (HR, 0.270 [P=.003] and 0.493 [P=.04], respectively). Statin use was associated with improved time to death for patients aged >65 years but not for those ≤65 years old.

CONCLUSION

Statin use during hospitalization for SARS-CoV-2 infection was associated with reduced 28-day mortality rates. Well-designed randomized control trials are needed to better define this relationship.

Liver injury in COVID-19: Known and unknown

Since the first report of the coronavirus disease 2019 (COVID-19) in December 2019 in Wuhan, China, the outbreak of the disease is currently continuously evolving. Previous studies have shown varying degrees of liver damage in patients with COVID-19. However, the exact causes of liver injury and the relationship between COVID-19 and liver injury is unclear. This article describes liver injury induced by COVID-19, analyzes its causes, and discusses the treatment and prognosis of liver damage in patients with COVID-19.

Statins Are Associated with Improved 28-day Mortality in Patients Hospitalized with SARS-CoV-2 Infection

Background:

Statins may be protective in viral infection and have been proposed as treatment in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection.

Objective:

We evaluated the effect of statins on mortality in four groups hospitalized with (SARS-CoV-2) infection (continued statin, newly initiated statin, discontinued statin, never on statin).

Design:

In a single center cohort study of 1179 patients hospitalized with SARS-CoV-2 infection, the outcome of death, Intensive Care Unit (ICU) admission or hospital discharge was evaluated. Patients’ statin use, laboratory data, and co-morbidities were determined via chart review and electronic health records. Using marginal structural models to account for timing of statin initiation and competing risks, we compared the likelihood of severe outcomes in the four statin exposure groups.

Setting:

Academic medical center in the United States

Participants:

Patients hospitalized with SARS-CoV-2 infection

Measurements:

28-day mortality, ICU admission, or discharge

Results:

Among 1179 patients, 360 were never on a statin, 311 were newly initiated on a statin, 466 were continued on a statin, and 42 had a statin discontinued. In this cohort, 154 (13.1%) patients died by 28-days. With marginal structural model analysis, statin use reduced the hazard of 28-day mortality (HR 0.566 [CI 0.372, 0.862], p = 0.008). Both new initiation of statins (HR 0.493 [CI 0.253, 0.963], p=0.038) and continuing statin therapy reduced the hazard of 28-day mortality (HR 0.270 [CI 0.114, 0.637], p=0.003). Sensitivity analysis found that statin use was associated with improved mortality for patients > 65 years, but not for patients 65 years or younger.

Limitation:

Observational design

Conclusion:

Statin therapy during hospitalization for SARS-CoV-2 infection, including new initiation and continuation of therapy, was associated with reduced short-term mortality.