The etiology, diagnosis and prevention of liver cirrhosis: part 1 of a series on liver cirrhosis

Mental health and quality of life in patients with chronic liver disease: a single-center structural equation model

BACKGROUND

Chronic liver disease (CLD) is one of the leading disease burdens in Pakistan. Until now, there has only been limited focus in the country on providing health services through tertiary services in urban cities, whereas there is almost no research in Pakistan on the mental health and quality of life of CLD patients. This study aimed to understand which predictors influence the mental health and quality of life of CLD patients in order to advise better policy protection.

METHODS

Data was collected from CLD patients at the Pakistan Kidney and Liver Institute and Research Centre, Lahore, Pakistan. A total of 850 respondents were part of the final sample. The age of respondents ranged from 18 to 79 years and included the following diagnosis: (i) Chronic Viral Hepatitis (n = 271), (ii) Cirrhosis (n = 259), (iii) Hepatocellular Carcinoma (n = 193), and (iv) Non-viral Liver Disease (n = 127).

RESULTS

Mean results reveal that females as well as illiterate patients need more support for mental health and communication with their physician; whereas men need more support to develop coping strategies. Structural equation modelling results reveal that the severity of symptoms (β = 0.24, p < 0.001), coping strategies (β=-0.51, p < 0.001), and doctor communication (β=-0.35, p < 0.001) predict mental health. Quality of life is associated with the severity of symptoms (β=-0.36, p < 0.001), coping strategies (β = 0.26, p < 0.05), and doctor communication (β = 0.09, p < 0.05).

CONCLUSIONS

A 'bio-psycho-social-spiritual' model is recommended for Pakistan's CLD patients which includes the integration of social officers to provide support in four key areas to secure mental health and quality of life of patients.

Serum biomarkers for liver fibrosis assessment

Liver fibrosis is the result of chronic liver injury of different etiologies produced by an imbalance between the synthesis and degeneration of the extracellular matrix and dysregulation of physiological mechanisms. Liver has a high regenerative capacity in the early stage of chronic diseases so a prompt liver fibrosis detection is important. Consequently, an easy and economic tool that could identify patients with liver fibrosis at the initial stages is needed. To achieve this, many non-invasive serum direct, such as hyaluronic acid or metalloproteases, and indirect biomarkers have been proposed to evaluate liver fibrosis. Also, there have been developed formulas that combine these biomarkers, some of them also introduce clinical and/or demographic parameters, like FIB-4, non-alcoholic fatty liver disease fibrosis score (NFS), enhance liver fibrosis (ELF) or Hepamet fibrosis score (HFS). In this manuscript we critically reviewed different serum biomarkers and formulas for their utility in the diagnosis and progression of liver fibrosis.

Biomarcadores séricos para la evaluación de la fibrosis hepática

La fibrosis hepática se desarrolla como respuesta a la presencia de daño hepático crónico de diferentes etiologías, provocando un desequilibrio entre la síntesis y degeneración de la matriz extracelular y la desregulación de diversos mecanismos fisiológicos. En los estadios iniciales de las patologías crónicas, el hígado posee una elevada capacidad de regeneración, por lo que la detección temprana de la fibrosis hepática resulta esencial. En este contexto, es preciso contar con herramientas sencillas y económicas que permitan detectar la fibrosis hepática en sus fases iniciales. Para evaluar la fibrosis hepática, se han propuesto multitud de biomarcadores séricos no invasivos, tanto directos, como el ácido hialurónico o las metaloproteasas, como indirectos. Así mismo, se han desarrollado diversas fórmulas que combinan dichos biomarcadores junto con parámetros demográficos, como el índice FIB-4, el índice de fibrosis en la enfermedad de hígado graso no alcohólico (NFS, por sus siglas en inglés), la prueba ELF o el score de fibrosis Hepamet (HFS, por sus siglas en inglés). En el presente manuscrito, realizamos una revisión crítica del valor diagnóstico y pronóstico de los diferentes biomarcadores séricos y fórmulas actualmente existentes.

Role of albumin infusion in cirrhosis-associated complications

Cirrhosis is an advanced-stage liver disease that occurs due to persistent physiological insults such as excessive alcohol consumption, infections, or toxicity. It is characterised by scar tissue formation, portal hypertension, and ascites (accumulation of fluid in the abdominal cavity) in decompensated cirrhosis. This review evaluates how albumin infusion ameliorates cirrhosis-associated complications. Since albumin is an oncotic plasma protein, albumin infusion allows movement of water into the intravascular space, aids with fluid resuscitation, and thereby contributes to resolving cirrhosis-induced hypovolemia (loss of extracellular fluid) seen in ascites. Thus, albumin infusion helps prevent paracentesis-induced circulatory dysfunction, a complication that occurs when treating ascites. When cirrhosis advances, other complications such as spontaneous bacterial peritonitis and hepatorenal syndrome can manifest. Infused albumin helps mitigate these by exhibiting plasma expansion, antioxidant, and anti-inflammatory functions. In hepatic encephalopathy, albumin infusion is thought to improve cognitive function by reducing ammonia concentration in blood and thereby tackle cirrhosis-induced hepatocyte malfunction in ammonia clearance. Infused albumin can also exhibit protective effects by binding to the cirrhosis-induced proinflammatory cytokines TNFα and IL6. While albumin administration has shown to prolong overall survival of cirrhotic patients with ascites in the ANSWER trial, the ATTIRE and MACHT trials have shown either no effect or limitations such as development of pulmonary oedema and multiorgan failure.  Thus, albumin infusion is not a generic treatment option for all cirrhosis patients. Interestingly, cirrhosis-induced structural alterations in native albumin (which lead to formation of different albumin isoforms) can be used as prognostic biomarkers because specific albumin isoforms indicate certain complications of decompensated cirrhosis.

Health-Related Quality of Life Assessment for Liver Cirrhosis Patients at a Tertiary Care Hospital in Karachi, Pakistan

Background The global health challenge of cirrhosis affects millions of individuals. Still, there is a notable lack of research on the health-related quality of life (HRQOL) of cirrhosis patients, especially in specific regions. This study aims to assess the impact of cirrhosis on HRQOL, including factors influencing it in a tertiary care setting in Pakistan. Methodology A cross-sectional study was conducted on a cohort of 115 patients diagnosed with cirrhosis, confirmed on imaging. HRQOL was measured using the short-form 36 (SF-36) survey. Furthermore, socioeconomic factors and self-rated health perceptions regarding HRQOL were recorded. Factors Influencing HRQOL domains in liver cirrhosis patients were also analyzed. Results Among 115 liver cirrhosis patients, 63.5% (N=73) were aged 40-60 years, and 73.9% (N=85) lived primarily in urban areas. HRQOL assessments highlighted moderate disability in physical functioning (62.6 ± 26.5) and notable impacts on mental health, emotional well-being, and bodily pain. Statistical analysis demonstrated the complexity of factors influencing HRQOL. Physical functioning was significantly associated with a higher Child-Turcotte-Pugh class, diabetes mellitus, hypertension, smoking status, and family monthly income (p-value < 0.05). While the duration of liver cirrhosis showed a significant association with bodily pain (p < 0.05). Additionally, residence status with social well-being (p-value = 0.01), and family monthly income with vitality (p-value < 0.05).  Conclusion Our study in Pakistan highlights significant impacts on the HRQOL of liver cirrhosis patients, affecting physical function, mental health, emotional well-being, and bodily pain. Factors influencing HRQOL include liver disease severity, comorbidities, and socio-economic status. Recommendations include educational programs and specialized nursing care to address diverse challenges. The findings stress the importance of a personalized approach to patient care, urging urgent, targeted efforts to improve the health-related standard of life for cirrhotic patients.

Review on Kidney-Liver Crosstalk: Pathophysiology of Their Disorders

Kidney-liver crosstalk plays a crucial role in normal and certain pathological conditions. In pathologic states, both renal-induced liver damage and liver-induced kidney diseases may happen through these kidney-liver interactions. This bidirectional crosstalk takes place through the systemic conditions that mutually influence both the liver and kidneys. Ischemia and reperfusion, cytokine release and pro-inflammatory signaling pathways, metabolic acidosis, oxidative stress, and altered enzyme activity and metabolic pathways establish the base of this interaction between the kidneys and liver. In these concomitant kidney-liver diseases, the survival rates strongly correlate with early intervention and treatment of organ dysfunction. Proper care of a nephrologist and hepatologist and the identification of pathological conditions using biomarkers at early stages are necessary to prevent the complications induced by this complex and potentially vicious cycle. Therefore, understanding the characteristics of this crosstalk is essential for better management. In this review, we discussed the available literature concerning the detrimental effects of kidney failure on liver functions and liver-induced kidney diseases.

Revealing curcumin therapeutic targets on SRC, PPARG, MAPK8 and HSP90 as liver cirrhosis therapy based on comprehensive bioinformatic study

Cirrhosis naturally progresses through three stages: compensated, decompensated, and late decompensated, which carry an elevated risk of death. Although curcumin's anti-cirrhosis effects have been studied, underlying mechanism in preventing cirrhosis progression and the correlation between curcumin's action with upregulated genes remains insufficiently explored. In this study, we employed network pharmacology approach to construct a drug-target-disease network through bioinformatics and validate the findings with molecular docking and dynamic simulation. The curcumin-targeted liver cirrhosis network encompassed 54 nodes with 282 edges in protein-protein interactions (PPI) network. By utilizing network centrality analysis, we identified eight crucial genes. KEGG enrichment pathway revealed that these crucial genes are involved in pathway of cancer, endocrine resistance, estrogen signaling, chemical carcinogenesis-receptor activation, lipid metabolism, and atherosclerosis. Notably, these eight genes predominantly participate in cancer-related pathways. Further investigation revealed upregulation of four genes and downregulation of four others in hepatocellular carcinoma patients. These upregulated genes-MAPK8, SRC, PPARG, and HSP90AA1-strongly correlated with reduced survival probability in liver hepatocellular carcinoma patients with survival times approximately under 4000 days (∼11 years). Molecular docking and molecular dynamic results exhibited curcumin's superior binding affinities and stability compared to native ligands of MAPK8, SRC, PPARG, and HSP90AA1 within 50 ns simulations. Moreover, MM-GBSA analysis showed stronger binding energy of curcumin to MAPK8, SRC, and HSP90AA1 than native ligand. In conclusion, this study provides valuable insights into curcumin's potential mechanisms in preventing liver cirrhosis progression, specifically in HCC. These findings offer a theoretical basis for further pharmacological research into anti-HCC effect of curcumin.Communicated by Ramaswamy H. Sarma.

Increasing Prevalence and High Survival Rate of Liver Transplanted Patients with NASH and PSC Cirrhosis

BACKGROUND

Epidemiological studies on liver transplant (LT) patients can provide valuable information about the etiology and trends of cirrhosis. The present study aimed to investigate the prevalence and trend of different etiologies and survival rates of LT patients at the Namazi Transplant Center in Shiraz, Iran, between 2001 and 2018.

METHODS

In this single-center, retrospective cohort study, the demographic and clinical characteristics of 3751 patients who underwent LT and met the study inclusion criteria, including age, gender, blood group, body mass index, model for end-stage liver disease (MELD) score, cause of cirrhosis, and diabetes, were extracted from patients' physical or electronic medical records between 2001 and 2018.

RESULTS

The MELD scores of LT patients with primary sclerosing cholangitis (PSC), hepatitis B virus (HBV), and non-alcoholic steatohepatitis (NASH) cirrhosis significantly decreased over the study period (P<0.001). Among the LT patients, HBV infection had the highest frequency (21.09%), followed by cryptogenic (17.33%) and PSC (17.22%). The proportion of patients with PSC and NASH (both P<0.001) cirrhosis was significantly increased, so that PSC cirrhosis (2016: 19.4%, 2018: 18.8%) surpassed HBV (2016: 18.4%, 2018: 13.5%), autoimmune hepatitis (2016: 11.7%, 2018: 12.7%), and cryptogenic cirrhosis (2016: 16.1%, 2018:14%) as the leading indication for LT from 2016 to the end of the study period. Fortunately, these patients had a better survival rate than other common diseases (HR: 0.53, CI: 0.43‒0.66; P<0.001).

CONCLUSION

The proportion of NASH and PSC cirrhosis significantly increased during the 18 years of study. However, these patients had an improved survival rate. Therefore, health organizations should pay more attention to non-communicable diseases, especially fatty liver disease and cholangitis.

Liver Transplantation for Hepatocellular Carcinoma in Patients with Inherited Metabolic Liver Diseases: A Single-Center Analysis

BACKGROUND/AIMS

Liver transplantation is an acceptable treatment for some selected hepatocellular carcinoma. We report our experience of 6 patients with liver transplantation for hepatocellular carcinoma with background inherited metabolic disease.

MATERIALS AND METHODS

This is a single-center retrospective, descriptive study. Consecutive patients who underwent liver transplantation for hepatocellular carcinoma with background inherited metabolic disease were included in the study. The record of the patients was accessed, and the following data were extracted: sociodemographic variables, type of metabolic disease, date of liver transplantation, tumor characteristics, laboratory parameters, Model for End-Stage Liver Disease score, immediate- and long-term outcome after transplantation, disease-free survival, and overall survival. Data were analyzed using Statistical Package for the Social Sciences version 25.0.

RESULTS

Six patients received liver transplantation for hepatocellular carcinoma with background inherited metabolic liver disease. The median age was 4.5 years. The median Model for End-Stage Liver Disease score was 29.30. The median maximum tumor diameter was 2.15 cm. Three patients had multiple tumor nodules. Half of the patients had microvascular invasion. Four of the patients had a moderately differentiated tumor. Progressive familial intrahepatic cholestasis type II is the commonest inherited metabolic disease seen in 3 patients. Median follow-up is 46.1 months. Half of the patients are currently more than 5 years post liver transplantation with no features of recurrence. The estimated survival rates at 1, 3, and 5 years are 100%, 83.3%, and 83.3%, respectively.

CONCLUSION

Liver transplant for these categories of patients is associated with good disease-free and overall survival, even in the presence of some seemingly poor prognostic features.

Circulating neutrophil anti-pathogen dysfunction in cirrhosis

Neutrophils are the largest population of leucocytes and are among the first cells of the innate immune system to fight against intruding pathogens. In patients with cirrhosis, neutrophils exhibit altered functionality, including changes in phagocytic ability, bacterial killing, chemotaxis, degranulation, reactive oxygen species production and NET (neutrophil extracellular trap) formation. This results in their inability to mount an adequate antibacterial response and protect the individual from infection. Prognosis and survival in patients with cirrhosis are greatly influenced by the development of infectious complications. Multidrug-resistant bacterial infections in patients with cirrhosis are currently a growing problem worldwide; therefore, alternative methods for the prevention and treatment of bacterial infections in cirrhosis are urgently needed. The prevention and treatment of neutrophil dysfunction could be a potential way to protect patients from bacterial infections. However, the reasons for changes in neutrophil function in cirrhosis are still not completely understood, which limits the development of efficient therapeutic strategies. Both cellular and serum factors have been proposed to contribute to the functional impairment of neutrophils. Herein, we review the current knowledge on features and proposed causes of neutrophil dysfunction in cirrhosis, with a focus on current knowledge gaps and limitations, as well as opportunities for future investigations in this field.

Uncovering the Cardiovascular Threat: A Comprehensive Examination of Liver Fibrosis and Subclinical Atherosclerosis in Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) has emerged as a global epidemic intricately linked to the rising tide of obesity and metabolic syndrome. This comprehensive review delves into the complex web of relationships between NAFLD, liver fibrosis, and subclinical atherosclerosis, shedding light on their interplay, shared risk factors, and clinical implications. NAFLD encompasses a spectrum of liver conditions, from the benign non-alcoholic fatty liver (NAFL) to the more severe non-alcoholic steatohepatitis (NASH), characterized by inflammation and hepatocellular injury. Central to the discussion is the insidious development of liver fibrosis, the ominous harbinger of progressive liver damage, cirrhosis, and hepatocellular carcinoma. The increasing prevalence of NAFLD, now affecting a quarter of the global population, poses a significant public health challenge. Its association with obesity, insulin resistance, and metabolic syndrome highlights the multifactorial nature of this disease. However, NAFLD's repercussions extend beyond the liver. This review unveils a potent connection between NAFLD and subclinical atherosclerosis, the early precursor to cardiovascular disease. Individuals with NAFLD face an elevated risk of atherosclerosis, even without traditional cardiovascular risk factors. The intricate link between these two conditions is illuminated through shared pathophysiological pathways, including systemic inflammation, insulin resistance, and dyslipidemia. Understanding the interplay between liver fibrosis and subclinical atherosclerosis has profound clinical implications. Patients with advanced fibrosis or cirrhosis are not only at risk of liver-related complications but also of cardiovascular events. This necessitates a holistic approach to patient care, with lifestyle modifications and pharmacological interventions simultaneously managing both conditions. Physicians must prioritize early detection and collaborate across disciplines to provide comprehensive care. Looking ahead, the future holds promising avenues of research. Emerging areas include genetics and precision medicine, microbiome research, and epigenetics, which may unveil new therapeutic targets. Innovations in diagnostics and therapeutics, such as non-invasive biomarkers and combination therapies, offer hope for more effective management. Long-term outcomes and survivorship research will provide insights into the lasting impact of interventions. In conclusion, this review underscores the imperative of addressing liver fibrosis and atherosclerosis in the context of NAFLD. It is a call to action for healthcare professionals, researchers, and policymakers to work collaboratively, promote early detection, and advance our understanding of these interconnected conditions. By doing so, we can enhance patient outcomes and chart a course toward a healthier future for those grappling with NAFLD and its intricate web of consequences.

Patients With Cirrhosis Have Higher Costs of Care, Longer Length of Stays, and More Perioperative Complications Following Total Knee Arthroplasty: A National Inpatient Sample-Based Study

Background Cirrhosis is a growing disease affecting millions of people in the United States annually. Many cirrhosis patients undergo significant procedures and are met with increased risks such as encephalopathy, impaired immune response, ascites, variceal bleeding, renal disease, and increased malnutrition. Many cirrhosis patients need to undergo major surgical procedures such as total knee arthroplasty (TKA); however, perioperative complications following TKA in cirrhosis patients have not been studied. The purpose of this study was to analyze the demographic characteristics and perioperative complications of cirrhosis patients following TKA. Methods Using the National Inpatient Sample (NIS) database, we looked at retrospective data from the years 2016-2019 to analyze the incidence of perioperative complications, length of stay (LOS), and the cost of care (COC) among patients undergoing TKA who were categorized as cirrhosis patients, compared with those who are not. A propensity match was conducted to consider associated comorbidities that influence perioperative complications. Results Of the 558,256 patients analyzed who underwent TKA, 1670 (0.3%) were diagnosed with cirrhosis. After matching, cirrhosis patients had a longer LOS (4.22 vs. 3.68 days, p=0.016) and COC ($90,624 vs. 80676.87, p<0.001) than patients in the control group. Moreover, cirrhosis patients had a higher likelihood of developing acute renal failure (odds ratio (OR): 3.05, 95% CI: 2.07-4.50, p<0.001), blood loss anemia (OR: 1.60, 95% CI: 1.34-1.92, p<0.001), periprosthetic fracture (OR: 3.27, 95% CI: 1.31-8.18, p=0.007), periprosthetic infection (OR: 3.14, 95% CI: 1.99-4.95, p<0.001), and blood transfusions (OR: 1.62, 95% CI: 1.12-2.35, p=0.009) than patients in the control group. Conclusion The cirrhosis group had a significantly higher COC, longer LOS, and higher rates of perioperative complications than non-cirrhosis patients. This data will help providers make informed decisions about patient care and resource allocation for cirrhosis patients undergoing TKA.

The Demographic and Clinicopathological Characteristics of Hepatopancreatobiliary Cancers From a Specialized Center in India

Introduction Hepatopancreatobiliary (HPB) cancers are a distinct group requiring specialized multidisciplinary care. The present study was an analysis of HPB cancers. Methods The institutional data for two years from 2017 to 2018 was retrieved from the hospital-based cancer registry (HBCR) database in Excel format (Microsoft® Corp., Redmond, WA). The demographic details, method of diagnosis, tumor characteristics, and disease extent of the patients with HPB primary sites were retrospectively analyzed. Results Out of the 1417 patients with HPB malignancies, 1193 were analyzed. Most of the patients at our center hailed from North India. The distribution of HPB cancers was as follows: hepatocellular carcinoma (HCC) (n=717, 60.1%), gallbladder (GB) (n=230, 19.3%), periampullary carcinoma (n=76, 6.37%), head of the pancreas (HOP) (n=55, 4.61%), extrahepatic bile duct (EBD) (n=53, 4.44%), intrahepatic bile duct (IBD) (n=32, 2.68%), and body of the pancreas (BOP) (n=30, 2.52%). The most common disease presentation of HPB cancers was in the seventh and sixth decades of life. Male predominance was seen in all HPB cancers except in GB with a higher incidence in females. The predominant cause of chronic liver disease (CLD) with HCC was viral-related (53.7%) with hepatitis B virus (HBV) (34.3%) higher than hepatitis C virus (HCV) (19.2%) followed by non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) (24.8%) and then alcohol. Adenocarcinoma was the most common morphology in pancreatobiliary malignancies. The disease presentation was locoregional in 63.4% of HCC, 69.7% of periampullary carcinoma, and 50.9% of HOP cases. The patients with EBD and IBD cancers presented commonly with locoregional disease extent in 60.4% and 62.5%, respectively. Perihilar subsite was more commonly detected (71.7%) as compared to the distal one in the patients with EBD cancers. The patients with GB cancers (GBC) presented with distant metastases in 53.5% and locoregional disease in 33%. Distant metastases were present in 76.7% of the patients with BOP cancers. The liver was a common site of distant metastases in GB, periampullary, and pancreatic cancers. Conclusions The present study highlights the characteristics and the variations in disease presentation in different primary tumor sites of HPB cancers. In view of the common locoregionally advanced disease presentation of HCC, the patients with CLD need surveillance for the early detection of lesions. As the patients with HPB cancers show advanced disease presentation, effective locoregional and systemic therapies are needed.

Dietary fiber intake and mortality among survivors of liver cirrhosis: A prospective cohort study

Background

Liver cirrhosis is associated with significant nutritional risks and poor survival rates. Little is known about the impact of dietary factors on metabolic complications and mortality from cirrhosis.

Aim

The present study investigated the potential associations between dietary fibers and the risk of cirrhosis-related mortality.

Methods

In this prospective study, 121 ambulatory cirrhotic patients with more than six months of cirrhosis diagnosis were followed-up for 4 years. Dietary intakes were assessed using a 168-item semi-quantitative validated food frequency questionnaire. Crude and multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated through cox proportional hazards regression models.

Results

Comparing the highest versus the lowest tertile, soluble and insoluble fiber intake was associated with 62% (HR = 0.38, 95% CI = 0.045-3.5, p trend = 0.047) and 73% (HR = 0.27, 95% CI = 0.06-1.2, p trend = 0.021) lower mortality risk, respectively, after full adjustment for potential confounders. Higher intakes of total fiber were inversely but non-significantly associated with mortality risk.

Conclusion

Comprehensive assessment of dietary fiber intake associations with cirrhosis-related mortality showed that higher intakes of soluble and insoluble fiber were significantly associated with reduced mortality risk.

The use of phase angle in patients with digestive and liver diseases

Diseases of the liver and the digestive system can lead to malnutrition through an action of reduced food intake or nutrient use, inflammation and impaired metabolism, which result in substantial changes in body composition. Frequently, malnutrition manifests itself with weight loss and reduced muscle mass. However, weight loss and body mass index lack sensitivity to detect the loss of muscle mass and are not informative in distinguishing body water compartments and in characterizing their distribution. This issue is particularly relevant to these two disease models, which are frequently associated with fluid volume imbalances. Phase angle is a useful indicator for cell membrane integrity, water distribution between the intracellular and extracellular spaces and prediction of body cell mass as it is described by measured components of electrical impedance. Malnutrition, inflammation and oxidative stress impair electric tissue properties leading to lower values of PhA. In patients with inflammatory bowel and liver diseases, PhA was consistently found to be related to nutritional status and body composition, particularly the depletion of lean body mass and sarcopenia. It has been associated with prognosis, disease stage and severity and found to be helpful in monitoring fluid shifts and response to interventions.

A Review of Stem Cell Technology Targeting Hepatocyte Growth as an Alternative to Organ Transplantation

Currently, the only feasible option for patients with progressive and/or end-stage organ degeneration is to undergo transplantation. Due to the growing unmatched demand of available organ donors and, as a consequence, the continuous growth of patients' waiting lists, the development of new tissue engineering technologies is a relevant need. In this chapter, we will focus on the liver as a model organ to discuss contemporary tissue engineering strategies. Induced pluripotent cells are an attractive alternative to serve as a cell source for tissue engineering applications due to their pluripotency, the potentiality to generate autologous transplantation, and for their high proliferation rate. Among the main liver tissue engineering technologies, 3D bioprinting, hepatic organoids, and decellularization/recellularization of biological matrixes have grown much attention as alternatives to derive functional liver grafts. Thus, this chapter will discuss how recent publications have demonstrated the use of induced pluripotent cells in the development of the aforementioned technologies. Bioprinting is an additive manufacturing biofabrication process where cells are dispersed within a matrix formulation (i.e., bioink) and extruded in a modified 3D-printer. Polymers within bioink can be cross-linked to increase stiffness. Hepatic spheroids showed greater viability and liver function, due to preserved epithelial phenotype over time. Organoid is multi-lineage tissue constructs derived from a stem cell that recapitulates the early stages of organogenesis. The influence of cellular composition of non-parenchymal cells using induced pluripotent-derived cells or primary adult cells for hepatic organoid formation was recently tested. Decellularization is a process where harvested tissues or organs are washed with a detergent-based solution, to lyse and remove all cellular components. The final product is an extracellular scaffold with preserved tissue vasculature and ultra-structure, which can be used for subsequent recellularization with recipient cells. This chapter sheds light on recent works on the use of induced pluripotent-derived cells for liver tissue engineering approaches and on how such technologies could potentially generate therapeutic alternatives for patients on waiting lists for liver transplantation.

Survival of primary liver cancer for people from culturally and linguistically diverse backgrounds in Australia

BACKGROUND

Survival for Primary Liver Cancer (PLC) has been investigated in Australia, but limited work has been conducted on the burden for people with different socioeconomic status, region of residence, causes of PLC, and culturally and linguistically diverse (CALD) backgrounds. This study aimed to cover this gap in the literature by investigating PLC survival with the aforementioned factors.

METHODS

This study linked four administrative datasets: Victorian Cancer Registry, Admitted Episodes Dataset, Emergency Minimum Dataset, and Death Index. The cohort was all cases with a PLC notification within the Victorian Cancer Registry between 01/01/2008 and 01/01/2016. The Kaplan-Meier method was used to estimate survival probabilities and the log-rank test was used to compare the difference in survival between subgroups. The Cox proportional hazard model was used to explore factors associated with PLC survival.

RESULTS

The 1-, 3- and 5-year survival rates were 50.0%, 28.1% and 20.6%, respectively, with a median survival of 12.0 months (95% confidence interval (CI): 11.0 - 12.9 months). Higher survival was associated with younger age, hepatocellular carcinoma, and higher socio-economic status. People born in Asian, African, and American regions had higher survival than those born in Australia and New Zealand. Cases with viral hepatitis as an identified aetiology had higher survival than those whose PLC was related to alcohol consumption (hazard ratio=1.52, 95% CI: 1.19 - 1.96), diabetes and fatty liver disease (hazard ratio=1.35, 95% CI: 1.08 - 1.68).

CONCLUSION

Survival outcomes for people diagnosed with PLC were still poor and affected by many factors. Asian and African cases had better survival than Australian and New Zealand patients as PLC in Asian and African cases was mostly caused by viral hepatitis. Metropolitan areas were associated with a higher survival than rural areas, not only due to accessibility to surveillance and healthcare services but also because the majority of overseas-born patients reside in metropolitan areas.

Sociodemographic and medical characteristics of liver cirrhosis deaths in a Ghanaian tertiary hospital

Objective

Cirrhosis is common in Ghana because of its high risk factors prevalence. However, information on cirrhosis in Ghana is lacking. This study aimed to study the clinical, and laboratory characteristics of cirrhotic patients in a tertiary hospital in Ghana.

Design

This was a retrospective study of sociodemographic characteristics, symptoms and signs, biochemical and fibrotic indices, treatments, and complications data of 247 patients with cirrhosis who died on admission.

Setting

This study was carried out at the Gastroenterology Unit of the Korle-Bu Teaching Hospital, Ghana.

Results

Two-thirds (68.0%) of the patients were within 30 to 60 years, with more than half (73.7%) being males. The most common aetiological factors among the patients were Hepatitis B virus infection (53.8%), alcohol use (31.6%) and Hepatitis C virus infection (4.9%). More than half (55.0%) of the patients reported late for admission, and 67.2% died within the first two weeks of admission. The most common clinical feature was abdominal distension (61.1% of patients), and the least was upper-abdominal mass (14.2%). The levels of most liver test parameters were elevated, fibrotic indices were high, and haemoglobin and albumin levels were reduced. More than half (53.8%) of the patients were in Child Pugh class B. The most common complication was hepatic encephalopathy; the least was hepato-renal syndrome. Definite treatment for complications of cirrhosis was lacking.

Conclusion

Deaths from cirrhosis at the hospital were mostly of young males with chronic hepatitis B infection. Implementation of hepatitis B prevention and treatment guidelines can help reduce cirrhosis deaths.

Funding

None declared.

A stacking ensemble machine learning model to predict alpha-1 antitrypsin deficiency-associated liver disease clinical outcomes based on UK Biobank data

Alpha-1 antitrypsin deficiency associated liver disease (AATD-LD) is a rare genetic disorder and not well-recognized. Predicting the clinical outcomes of AATD-LD and defining patients more likely to progress to advanced liver disease are crucial for better understanding AATD-LD progression and promoting timely medical intervention. We aimed to develop a tailored machine learning (ML) model to predict the disease progression of AATD-LD. This analysis was conducted through a stacking ensemble learning model by combining five different ML algorithms with 58 predictor variables using nested five-fold cross-validation with repetitions based on the UK Biobank data. Performance of the model was assessed through prediction accuracy, area under the receiver operating characteristic (AUROC), and area under the precision-recall curve (AUPRC). The importance of predictor contributions was evaluated through a feature importance permutation method. The proposed stacking ensemble ML model showed clinically meaningful accuracy and appeared superior to any single ML algorithms in the ensemble, e.g., the AUROC for AATD-LD was 68.1%, 75.9%, 91.2%, and 67.7% for all-cause mortality, liver-related death, liver transplant, and all-cause mortality or liver transplant, respectively. This work supports the use of ML to address the unanswered clinical questions with clinically meaningful accuracy using real-world data.

Diagnostic Accuracy of Elastography and Liver Disease: A Meta-Analysis

BACKGROUND

Ultrasound-based transient elastography (TE) is a non-invasive alternative to liver biopsy for the staging of hepatic fibrosis due to various chronic liver diseases. This meta-analysis aims to assess the diagnostic accuracy of TE for detecting liver cirrhosis (F4) and severe fibrosis (F3) in patients with chronic liver diseases, in comparison to the gold standard liver biopsy.

METHODS

A systematic search was performed using PubMed search engine following Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines from inception to May 2021. The meta-analysis studies evaluating the diagnostic accuracy of TE for severe fibrosis and cirrhosis were identified. We conducted a meta-meta-analysis to generate pooled estimates of the sensitivity, specificity, and diagnostic odds ratios (ORs) for F3 and F4 fibrosis stage.

RESULTS

We included five studies with a total of 124 sub-studies and 20,341 patients in our analysis. Three studies have reported the diagnostic accuracy of TE in detecting F3/severe fibrosis stage and found 81.9% pooled sensitivity (95% confidence interval (CI): 79.9-83.7%; P < 0.001) (I2 = 0%), 84.7% pooled specificity (95% CI: 81.3-87.6%) (I2 = 81%; P = 0.02). All five studies reported the diagnostic accuracy of TE in detecting F4/liver cirrhosis stage. We found 84.8% pooled sensitivity (95% CI: 81.4-87.7%) (I2 = 86.4%; P < 0.001), 87.5% pooled specificity (95% CI: 85.4-89.3%) (I2 = 90%; P < 0.001) and pooled diagnostic OR (41.8; 95% CI: 3.9 - 56.5) (I2 = 87%; P < 0.001).

CONCLUSIONS

Ultrasound-based TE has excellent diagnostic accuracy for identifying cirrhosis and liver fibrosis stages 3. Future studies should focus on estimating the diagnostic accuracy of other fibrosis stages in chronic liver disease patients. This will eventually decrease the risk associated with invasive liver biopsy.

Spleen and Liver Stiffness Evaluation by ARFI Imaging: A Reliable Tool for a Short-Term Monitoring of Portal Hypertension?

BACKGROUND

Assessment of hepatic venous pressure gradient (HVPG) is the most reliable, though invasive method for evaluation of portal hypertension. Non-invasive, elastography-based techniques are well established in diagnosis, but not in monitoring of portal hypertension. The aim of our prospective study was to determine the value of acoustic radiation force impulse (ARFI) elastography technique of the liver and spleen in diagnosis and monitoring of portal hypertension.

METHODS

We prospectively assessed portal hypertension by HVPG and corresponding elastography of the liver and spleen in 31 patients with liver cirrhosis and an indication for primary prophylaxis by non-cardio selective beta-blockers. Investigations were performed at baseline and a follow-up visit after 6-8 weeks. To address the known large variability of values for spleen elastography, well-defined corresponding areas in the spleen were used for baseline and follow-up elastography. Sensitivity, specificity, and AUC-ROC values for both spleen and liver elastography monitoring of portal hypertension were calculated.

RESULTS

Liver but not spleen elastography significantly correlated with HVPG results and was suitable for initial evaluation of portal hypertension. However, changes in HVPG results did not show any correlation with alterations of ARFI values from baseline to follow-up visits both for liver and spleen elastography. Spleen stiffness results were not homogeneous across the whole organ differing significantly between the upper, hilar, and bottom placed investigation areas.

CONCLUSIONS

In this prospective study ARFI-based assessment of liver elastography showed itself suitable for initial assessment but not for monitoring of portal hypertension. Spleen elastography was not appropriate for both, evaluation and monitoring of portal hypertension. A possible explanation for this new data that are in some contrast to previously published results is the degree of portal hypertension in our study, a comparatively short follow-up period, and well-defined investigation areas for spleen elastography in repetitive ARFI investigations. This trial is registered with NCT03315767.

Comparison of plasminogen activator inhibitor-1 levels in chronic hepatitis B patients with hepatic cirrhosis and without hepatic cirrhosis

Introduction: One of the hepatic cirrhosis manifestations is bleeding disorders. Among all the substance that plays a pivotal role in maintaining the balance between thrombosis and thrombolysis is PAI-1, synthesized by hepatocytes. The dynamics of increase and decrease of PAI-1 is a natural response to the ongoing hepatic cirrhosis, but may not be seen in non-hepatic cirrhosis. PAI-1 levels also depends on the stage of fibrosis. Several conditions may interfere with PAI-1 levels including age, body mass index, and gender Objectives: This study aims to find out the comparison of PAI-1 levels in hepatitis B patients with hepatic cirrhosis and without hepatic cirrhosis and to compare it with every stage of hepatic cirrhosis. Patients and Methods: This study is an observational analytical study with a cross-sectional approach conducted at Wahidin Sudirohusodo hospitals, Makassar. Subjects are chronic hepatitis B patients with and without hepatic cirrhosis which meet inclusion criteria. Serum PAI-1 levels were measured by using Bender MedSystems human plasminogen activator inhibitor-1 ELISA kit (BMS2033) and using the ELISA technique. Statistical analysis was performed using the Kolmogorov Smirnov normality test as well as the Mann-Whitney method. Statistical results are considered significant if the p-value <0.05. Results: The research was conducted on 60 subjects who meet inclusion criteria, consisting of 33 men and 27 women. There were 16 patients with hepatic cirrhosis. Levels of PAI-1 in hepatic cirrhosis was significantly different which lower than non-hepatic cirrhosis patient (0.43 ng/mL Vs 1.11 ng/mL, p=0.024).  By staging of hepatic fibrosis, stage F2 hepatic fibrosis had the highest levels of PAI-1, in contrast with end-stage hepatic fibrosis which had the lowest levels. Conclusion: Levels of PAI-1 fluctuate through different stages of hepatic fibrosis. The significant difference in PAI-1 levels in hepatic cirrhosis and non-hepatic cirrhosis demonstrates a correlation between PAI-1 and hepatic cirrhosis  Keywords: Chronic hepatitis B, Hepatic cirrhosis, Plasminogen Activator Inhibitor-1

Computational simulation of liver fibrosis dynamics

Liver fibrosis is a result of homeostasis breakdown caused by repetitive injury. The accumulation of collagens disrupts liver structure and function, which causes serious consequences such as cirrhosis. Various mathematical simulation models have been developed to understand these complex processes. We employed the agent-based modelling (ABM) approach and implemented inflammatory processes in central venous regions. Collagens were individually modelled and visualised depending on their origin: myofibroblast and portal fibroblast. Our simulation showed that the administration of toxic compounds induced accumulation of myofibroblast-derived collagens in central venous regions and portal fibroblast-derived collagens in portal areas. Subsequently, these collagens were bridged between central-central areas and spread all over areas. We confirmed the consistent dynamic behaviour of collagen formulation in our simulation and from histological sections obtained via in vivo experiments. Sensitivity analyses identified dead hepatocytes caused by inflammation and the ratio of residential liver cells functioned as a cornerstone for the initiation and progression of liver fibrosis. The validated mathematical model demonstrated here shows virtual experiments that are complementary to biological experiments, which contribute to understanding a new mechanism of liver fibrosis.

Structural changes of proteins in liver cirrhosis and consequential changes in their function

The liver is the site of synthesis of the majority of circulating proteins. Besides initial polypeptide synthesis, sophisticated machinery is involved in the further processing of proteins by removing parts of them and/or adding functional groups and small molecules tailoring the final molecule to suit its physiological purpose. Posttranslational modifications (PTMs) design a network of molecules with the common protein ancestor but with slightly or considerably varying activity/localization/purpose. PTMs can change under pathological conditions, giving rise to aberrant or overmodified proteins. Undesired changes in the structure of proteins most often accompany undesired changes in their function, such as reduced activity or the appearance of new effects. Proper protein processing is essential for the reactions in living beings and crucial for the overall quality control. Modifications that occur on proteins synthesized in the liver whose PTMs are cirrhosis-related are oxidation, nitration, glycosylation, acetylation, and ubiquitination. Some of them predominantly affect proteins that remain in liver cells, whereas others predominantly occur on proteins that leave the liver or originate from other tissues and perform their function in the circulation. Altered PTMs of certain proteins are potential candidates as biomarkers of liver-related diseases, including cirrhosis. This review will focus on PTMs on proteins whose structural changes in cirrhosis exert or are suspected to exert the most serious functional consequences.

Diagnostik erhöhter Leberwerte in der Primärversorgung – Befunde einer Studienreihe aus haus- und fachärztlicher Perspektive

Hintergrund In der Primärversorgung treten Leberwerterhöhungen häufig als Zufallsbefund in Erscheinung. Neben der Beachtung von Symptomen ist für eine effektive Abklärung entscheidend, welche Leberwerte als Indikatoren einbezogen und wann Patient*innen zur weiterführenden Diagnostik überwiesen werden. Ebenso kommt es auf eine geregelte Zusammenarbeit zwischen haus- und fachärztlicher Versorgungsebene an. Bislang fehlt es für den deutschsprachigen Raum an belastbaren Erkenntnissen über den Status quo hinsichtlich der Abklärung (unklarer) Leberwerterhöhungen im niedergelassenen und hausärztlichen Bereich. Der Überblicksartikel komprimiert die Bilanz einer explorativen Studienreihe, deren Ziel darin bestand, eine Bestandsaufnahme hinsichtlich des Status quo der hausarztbasierten Diagnostik (unklar) erhöhter Leberwerte zu leisten. Aus den Ergebnissen werden Ansatzpunkte einer Optimierung abgeleitet.

Methodik Zwischen 2017 und 2021 wurden 4 schriftliche Befragungen von Hausärzt*innen und gastroenterologischen Fachärzt*innen in verschiedenen Bundesländern durchgeführt. Die vorliegende Studienbilanz diskutiert die Gesamtbefunde komprimiert auf übergeordneter Ebene, geht jedoch auch auf spezifische Befunde ein.

Ergebnisse Mit Blick auf Abklärung erhöhter Leberwerte zeigen sich diverse Herausforderungen und Problematiken. So ziehen Hausärzt*innen stark unterschiedliche Laborparameter heran (95% γ-GT, 65% AST, 63% ALT), die sich in verschiedenen Clustern bündeln. Im Fall erhöhter Leberwerte präferiert eine Mehrheit der Hausärzt*innen ein kontrolliertes Zuwarten (66%), macht allerdings im Alltag oft aufgrund von diagnostischen Unsicherheiten von direkten Überweisungen zu Spezialist*innen Gebrauch (40%). In der Zusammenarbeit mit gastroenterologischen Fachärzt*innen bestehen aus hausärztlicher Sicht Schnittstellenprobleme, die u.a. mit der im Vorfeld geleisteten Abklärung sowie dem Überweisungszeitpunkt einhergehen. Sowohl Haus- als auch Fachärzt*innen erachten die Einführung eines evidenzbasierten Diagnosealgorithmus als wichtigen Ansatz für die Verbesserung der Früherkennung sowie eine bessere Koordination zwischen den Versorgungsebenen (80% bzw. 85%).

Diskussion Es sollte darauf hingewirkt werden, zu einer stärkeren Professionalisierung und Vereinheitlichung der primärärztlichen Diagnostik beizutragen und die Zusammenarbeit mit gastroenterologischen Spezialisten besser zu strukturieren. Dazu zählen ein breiteres Angebot von Fortbildungsformaten, die Entwicklung eines validierten Diagnosepfads und die feste Verankerung einer leberwertassoziierten Blutuntersuchung im Rahmen des Check-ups. Auch die Entwicklung einer hausarztbasierten Leitlinie zum Umgang mit erhöhten Leberwerten erscheint ratsam.

Urinary free cortisol is a reliable index of adrenal cortisol production in patients with liver cirrhosis

BACKGROUND

The measurement of total and free cortisol has been studied as a clinical index of adrenal cortisol production in patients with liver cirrhosis. Correlations between free plasma and salivary cortisol have previously been reported in stable cirrhotic patients. Urinary free cortisol constitutes an index of adrenal cortisol production; however, it has never been used in assessing adrenal function in patients with liver cirrhosis.

AIMS

The aim of this observational study was to determine associations between urinary free cortisol, serum total, salivary, measured and calculated plasma free cortisol levels in cirrhotics, determining which of them can be used as an indirect index of free cortisol levels. Moreover, we investigated the potential use of 24 h urinary free cortisol as a prognostic factor for mortality.

METHODS

Seventy-eight outpatients with liver cirrhosis were included. Serum, salivary and urinary free cortisol were measured using the electrochemiluminenscence immunoassay. Plasma free cortisol determination was conducted using a single quadrupole mass spectrometer. The quantification of free cortisol was achieved by determining the signal response on negative ESI-MS mode.

RESULTS

Twenty-four hour urinary free cortisol levels correlated with free cortisol determined by mass spectrometer, total cortisol and calculated free cortisol levels. Patients with low levels of urinary free cortisol presented a significantly higher mortality rate compared to those with high levels. The factors associated with death risk were determined by Cox regression. In the multivariate analysis, two models were applied; in the first model, CP score, PVT and urinary free cortisol were found to be significantly related to patients' survival, whereas in the second, MELD score, ascites and urinary free cortisol were independently related to survival.

CONCLUSIONS

This study suggests that 24 h urinary free cortisol could be considered as a potential index of adrenal cortisol production in patients with liver cirrhosis and it potentially detects patients with a high mortality risk.

Deep learning supports the differentiation of alcoholic and other-than-alcoholic cirrhosis based on MRI

Although CT and MRI are standard procedures in cirrhosis diagnosis, differentiation of etiology based on imaging is not established. This proof-of-concept study explores the potential of deep learning (DL) to support imaging-based differentiation of the etiology of liver cirrhosis. This retrospective, monocentric study included 465 patients with confirmed diagnosis of (a) alcoholic (n = 221) and (b) other-than-alcoholic (n = 244) cirrhosis. Standard T2-weighted single-slice images at the caudate lobe level were randomly split for training with fivefold cross-validation (85%) and testing (15%), balanced for (a) and (b). After automated upstream liver segmentation, two different ImageNet pre-trained convolutional neural network (CNN) architectures (ResNet50, DenseNet121) were evaluated for classification of alcohol-related versus non-alcohol-related cirrhosis. The highest classification performance on test data was observed for ResNet50 with unfrozen pre-trained parameters, yielding an area under the receiver operating characteristic curve of 0.82 (95% confidence interval (CI) 0.71–0.91) and an accuracy of 0.75 (95% CI 0.64–0.85). An ensemble of both models did not lead to significant improvement in classification performance. This proof-of-principle study shows that deep-learning classifiers have the potential to aid in discriminating liver cirrhosis etiology based on standard MRI.

Evaluation of elevated liver values in primary care - a series of studies on the status quo of care in Germany with special reference to alcoholic liver disease

BACKGROUND

In primary care, elevated liver values often appear as incidental findings. As well considering the presenting symptoms, key factors in effective diagnosis are which liver values to include as indicators and when to refer patients for further diagnostics. It is also important that there is coordinated collaboration between GPs and specialists. There has hitherto been a lack of reliable findings on the status quo regarding the evaluation of (abnormally) elevated liver values in primary care.

METHODS

Between 2017 and 2021, four written explorative surveys of GPs and gastroenterological specialists were conducted in various German states, aimed at taking stock of the current status of GP-based diagnostics of (abnormally) elevated liver values. In addition, interviews were conducted with 14 GPs and gastroenterological specialists. This review article discusses the overall findings of the series of studies in a condensed manner at a higher level. The article aims to derive starting points for optimising the diagnosis of liver cirrhosis in primary care.

RESULTS

There are various challenges and problems associated with the evaluation of elevated liver values. For example, GPs draw on very different laboratory parameters, which are combined in different clusters. When elevated liver values are found, a majority of GPs prefer a controlled wait-and-see period, but often make use of direct referrals to specialists due to diagnostic uncertainties. GPs report interface problems with gastroenterological specialists, which are associated, among other things, with the preliminary evaluation that has been made and the timing of referral. Both GPs and specialists consider the introduction of an evidence-based diagnostic algorithm to be an important starting point for improving early detection and better coordination between healthcare levels.

CONCLUSIONS

Efforts should be made to contribute to greater professionalisation and standardisation of primary care diagnostics and to better structure the interaction with gastroenterological specialists. These include a wider range of training formats, the development of a validated diagnostic pathway and the mandating of a liver function test as part of the check-up. The development of a GP-based guideline for managing elevated liver values also seems advisable.

A Novel Sprague-Dawley Rat Model Presents Improved NASH/NAFLD Symptoms with PEG Coated Vitexin Liposomes

Chronic liver disease (CLD) is a global threat to the human population, with manifestations resulting from alcohol-related liver disease (ALD) and non-alcohol fatty liver disease (NAFLD). NAFLD, if not treated, may progress to non-alcoholic steatohepatitis (NASH). Furthermore, inflammation leads to liver fibrosis, cirrhosis, and hepatocellular carcinoma. Vitexin, a natural flavonoid, has been recently reported for inhibiting NAFLD. It is a lipogenesis inhibitor and activates lipolysis and fatty acid oxidation. In addition, owing to its antioxidant properties, it appeared as a hepatoprotective candidate. However, it exhibits low bioavailability and low efficacy due to its hydrophobic nature. A novel rat model for liver cirrhosis was developed by CCL4/Urethane co-administration. Vitexin encapsulated liposomes were synthesized by the ‘thin-film hydration’ method. Polyethylene glycol (PEG) was coated on liposomes to enhance stability and stealth effect. The diseased rats were then treated with vitexin and PEGylated vitexin liposomes, administered intravenously and orally. Results ascertained the liposomal encapsulation of vitexin and subsequent PEG coating to be a substantial strategy for treating liver cirrhosis through oral drug delivery.

Association between viral hepatitis and increased risk of severe coronavirus disease 2019 (COVID-19) outcome: a systematic review and meta-analysis

Aim

The purpose of the current study is to analyze the potential association between viral hepatitis and the severity of COVID-19.

Background

Coronavirus disease 2019 (COVID-19) is a worldwide concern that has created major issues with many aspects. It is important to identify the risk factors for severe outcomes of this disease. To date, no association between viral hepatitis and severe COVID-19 has not been established.

Methods

Through November 5^th, 2020, the databases of PubMed, Google Scholar, and medRxiv were systematically searched using specific keywords related to the focus of the study. All articles published on COVID-19 and viral hepatitis were retrieved. The Mantel-Haenszel formula with random-effects models was used to obtain the risk ratio (RR) along with its 95% confidence intervals (CIs) for dichotomous variables. The two-tailed p-value was set with a value ≤0.05 considered statistically significant. Restricted-maximum likelihood meta-regression was done for several variables, such as age, gender, hypertension, diabetes, and other liver disease.

Results

Analysis results included a total of 16 studies with a total of 14,682 patients. Meta-analysis showed that viral hepatitis increases the risk of developing severe COVID-19 (RR 1.68 (95% CI 1.26 - 2.22), p = 0.0003, I ² = 21%, random-effect modeling). According to the meta-regression analysis, the association between viral hepatitis and severe COVID-19 was not influenced by age (p = 0.067), diabetes (p = 0.057), or other liver disease (p = 0.646).

Conclusion

An increase of severe COVID-19 risk is associated with viral hepatitis. To reduce the risk of COVID-19, patients with viral hepatitis should be monitored carefully.

Self-expandable metallic stents (SEMS) in esophageal varices post-band ulcer refractory bleeding: a retrospective study

Background

Post-variceal band ligation bleeding ulcer is a severe complication with considerable mortality. We tried evaluating self-expandable metallic stent (SEMS) with concern to the ulcer morphology not well studied.

Results

We did a retrospective analysis of patients with bleeding post-band ulcers and treated by SEMS with concern to control bleeding and 6 weeks survival. Twenty-eight patients studied had their age (mean ± S.D.) 57.8 ± 8.6 years, and 85.7% were males. The Child-Pugh score range was 5–12]. Control of bleeding by SEMS was achieved in 23 (82.1%) patients, and overall, 6-week survival was 75%. Both post-band ulcer types B (oozing blood and type C (active spurted) were a risk for 6 weeks mortality (P = 0.04, OR 1.58, CI 95% 1.12–2.23).

Conclusion

SEMS is considered an excellent choice to control esophageal post-banding ulcer bleeding and a definite treatment bridge.

Working relationship between primary and specialist care in analysing elevated liver values-a survey from the point of view of gastroenterologists

Elevated liver values are often an incidental finding in outpatient care. A solid working relationship between general practitioners and specialists plays as much of a role in effective diagnostics as do selection and examination of liver values and context as indicators for referral towards more in-depth diagnosis. This article focuses on the status quo as well as potential hurdles and challenges in the relationship between general practitioners and specialists with regard to analysing elevated liver values of uncertain origin. A total of 529 physicians in gastroenterological practices in the German states of Baden-Württemberg, Hesse and Thuringia were invited to take part in an online survey in 2020, of which 313 responded. This contribution focuses on those parts of the survey covering the relationship between general practitioners and specialists. According to the results, 72% of the surveyed gastroenterologists saw working relationships between general practitioners and specialists as beneficial and effective. Even so, a variety of challenges and difficulties in everyday care dominate. Specialists especially criticised preliminary analyses performed by general practitioners as well as time of referral. Apart from that, a wide majority (85%) saw a major role in a structured diagnostic algorithm towards improving early detection and coordination between primary and specialist care. The survey revealed problems in the relationship between general practitioners and specialists. Together with targeted training and further training programmes for general practitioners, a validated diagnostic algorithm for classifying and analysing elevated liver values may be a valuable tool for general practitioners to perform diagnostics and improve the structure within which they work with specialists.

Liver Cirrhosis, Etiology and Clinical Characteristics Disparities Among Minority Population

Liver cirrhosis (LC) is a common disease with varied primary causes and ethnic disparities. Clinical characteristics and outcomes of Arab Bedouin (AB) and Jewish patients with LC were retrospective collected and compared. We included 1048 patients, 95 (9%) Arab Bedouin and 953 (91%) Jewish patients. The incidence of cirrhosis was much lower among AB. Age at diagnosis was 47 ± 18 years among Bedouins compared to 61 ± 13 years (p < 0.001) among Jews. The most frequent causes of cirrhosis among Bedouin patients were fatty liver 21.1%, cryptogenic 20%, hepatitis B 17.9% and autoimmune hepatitis 15.8%, while hepatitis C (39.2%), fatty liver (17.2%) and alcoholic liver disease (14.4%) were most common among Jewish patients. An all-cause mortality of 48.4% was observed in AB patients compared to 66.4% in Jewish patients (p < 0.001). Significant disparities regarding incidence, clinical characteristics and outcomes of cirrhosis among Arab Bedouin compared with Jewish population were found.

Self-expandable metallic stents (SEMS) in esophageal varices post-band ulcer refractory bleeding: a retrospective study

Background

Post-variceal band ligation bleeding ulcer is a severe complication with considerable mortality. We tried evaluating self-expandable metallic stent (SEMS) with concern to the ulcer morphology not well studied.

Results

We did a retrospective analysis of patients with bleeding post-band ulcers and treated by SEMS with concern to control bleeding and 6 weeks survival. Twenty-eight patients studied had their age (mean ± S.D.) 57.8 ± 8.6 years, and 85.7% were males. The Child-Pugh score range was 5–12]. Control of bleeding by SEMS was achieved in 23 (82.1%) patients, and overall, 6-week survival was 75%. Both post-band ulcer types B (oozing blood and type C (active spurted) were a risk for 6 weeks mortality (P = 0.04, OR 1.58, CI 95% 1.12–2.23).

Conclusion

SEMS is considered an excellent choice to control esophageal post-banding ulcer bleeding and a definite treatment bridge.

Early Normalization of Alanine Aminotransferase during Antiviral Therapy Reduces Risk of Hepatocellular Carcinoma in HBV Patients

Potent antiviral agents effectively reduce liver-related events in patients with chronic hepatitis B. This study aimed to determine whether alanine aminotransferase normalization using potent antiviral agents was related to hepatocellular carcinoma development. From 2007 to 2017, we included 610 patients with chronic hepatitis B who received entecavir or tenofovir disoproxil fumarate. The patients were divided into the alanine aminotransferase normalization group (Gr.1) and non-normalization group (Gr.2) within a year of potent antiviral treatment. Liver-related events included hepatic encephalopathy, variceal bleeding, and ascites. The mortality rate and hepatocellular carcinoma incidence were investigated for each group. The patients who showed ALT normalization at 1 year of treatment were 397 (65.1%) of 610. During a median follow-up period of 86 months, 65 (10.7%) patients developed hepatocellular carcinoma. The cumulative incidence of hepatocellular carcinoma was significantly lower in Gr.1 than in Gr.2 (p < 0.001). Risk factors for alanine aminotransferase non-normalization were body mass index, cholesterol, and liver cirrhosis at baseline. Male sex, age, platelet level, alcohol use, presence of cirrhosis at baseline, and non-normalization after 1 year of treatment were independent risk factors for hepatocellular carcinoma. Alanine aminotransferase normalization within 1 year of initiating antiviral agents reduces the risk of hepatocellular carcinoma development.

Pathophysiology and Management of Variceal Bleeding

Cirrhosis is the fifth leading cause of death in adults. Advanced cirrhosis can cause significant portal hypertension (PH), which is responsible for many of the complications observed in patients with cirrhosis, such as varices. If portal pressure exceeds a certain threshold, the patient is at risk of developing life-threatening bleeding from varices. Variceal bleeding has a high incidence among patients with liver cirrhosis and carries a high risk of mortality and morbidity. The management of variceal bleeding is complex, often requiring a multidisciplinary approach involving pharmacological, endoscopic, and radiologic interventions. In terms of management, three stages can be considered: primary prophylaxis, active bleeding, and secondary prophylaxis. The main goal of primary and secondary prophylaxis is to prevent variceal bleeding. However, active variceal bleeding is a medical emergency that requires swift intervention to stop the bleeding and achieve durable hemostasis. We describe the pathophysiology of cirrhosis and PH to contextualize the formation of gastric and esophageal varices. We also discuss the currently available treatments and compare how they fare in each stage of clinical management, with a special focus on drugs that can prevent bleeding or assist in achieving hemostasis.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) levels are not associated with severity of liver disease and are inversely related to cholesterol in a cohort of thirty eight patients with liver cirrhosis

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is of particular importance in cholesterol metabolism with high levels contributing to hypercholesterolemia. Cholesterol and sphingolipids are low in patients with liver cirrhosis. Purpose of this study was to find associations of plasma PCSK9 with circulating cholesterol and sphingolipid species and measures of liver disease severity in patients with liver cirrhosis.

METHODS

PCSK9 protein levels were determined by ELISA in systemic vein (SVP), hepatic vein (HVP) and portal vein plasma of patients with mostly alcoholic liver cirrhosis. PCSK9 and LDL-receptor protein expression were analysed in cirrhotic and non-cirrhotic liver tissues.

RESULTS

Serum PCSK9 was reduced in patients with liver cirrhosis in comparison to non-cirrhotic patients. In liver cirrhosis, plasma PCSK9 was not correlated with Child-Pugh score, Model for End-Stage Liver Disease score, bilirubin or aminotransferases. A negative association of SVP PCSK9 with albumin existed. PCSK9 protein in the liver did not change with fibrosis stage and was even positively correlated with LDL-receptor protein levels. Ascites volume and variceal size were not related to PCSK9 levels. Along the same line, transjugular intrahepatic shunt to lower portal pressure did not affect PCSK9 concentrations in the three blood compartments. Serum cholesterol, sphingomyelin and ceramide levels did not correlate with PCSK9. Stratifying patients by high versus low PCSK9 levels using the median as cut-off, several cholesteryl ester species were even low in the subgroup with high PCSK9 levels. A few sphingomyelin species were also reduced in the patients with PCSK9 levels above the median. PCSK9 is highly expressed in the liver but systemic, portal and hepatic vein levels were similar. PCSK9 was not correlated with the inflammatory proteins C-reactive protein, IL-6, galectin-3, resistin or pentraxin 3. Of note, HVP PCSK9 was positively associated with HVP chemerin and negatively with HVP adiponectin levels.

CONCLUSIONS

In the cohort of patients with liver cirrhosis mostly secondary to alcohol consumption high PCSK9 was associated with low levels of certain cholesteryl ester and sphingomyelin species. Positive correlations of PCSK9 and LDL-receptor protein in the liver of patients with chronic liver injury are consistent with these findings.

Circulating non-coding RNAs as potential diagnostic biomarkers in liver diseases

The liver plays a principal role in the human body as a metabolic and detoxifying unit. Liver diseases are the world's major health problems and affect millions of people worldwide. Early detection of liver diseases is certainly effective in timely treatment and prevention of their progression. Liver injury is associated with significant alterations in immune responses and pattern changes in various tissue-related gene expressions and cytokine production. Increasing or decreasing the specific spectrum of non-coding RNAs in different phases of liver disease can be a criterion for diagnosis. Novel diagnostic biomarkers are needed for liver diseases. Currently, micro-RNAs (miRNAs) are known to play important roles in the diagnosis of liver diseases. Circulating biomarkers such as miRNA-assisted diagnosis can conceivably be helpful for the early treatment of liver diseases. In this review, we look at miRNAs and their potential applications in liver diseases as diagnostic biomarkers were investigated.

Extracellular Matrix Remodeling in Chronic Liver Disease

PURPOSE OF THE REVIEW

This review aims to summarize the current knowledge of the extracellular matrix remodeling during hepatic fibrosis. We discuss the diverse interactions of the extracellular matrix with hepatic cells and the surrounding matrix in liver fibrosis, with the focus on the molecular pathways and the mechanisms that regulate extracellular matrix remodeling.

RECENT FINDINGS

The extracellular matrix not only provides structure and support for the cells, but also controls cell behavior by providing adhesion signals and by acting as a reservoir of growth factors and cytokines.

SUMMARY

Hepatic fibrosis is characterized by an excessive accumulation of extracellular matrix. During fibrogenesis, the natural remodeling process of the extracellular matrix varies, resulting in the excessive accumulation of its components, mainly collagens. Signals released by the extracellular matrix induce the activation of hepatic stellate cells, which are the major source of extracellular matrix and most abundant myofibroblasts in the liver.

GRAPHICAL ABSTRACT

Severity of Non-B and Non-C Hepatitis Versus Hepatitis B and C Associated Chronic Liver Disease: A Retrospective, Observational, Comparative Study

Background and objectives

Chronic liver disease (CLD) encompasses a variety of etiologies, and the infectious causes are mainly hepatitis B and hepatitis C virus. Chronic alcohol abuse and non-alcoholic fatty liver disease also have a major contribution to CLD. The Child-Pugh scoring system indicates the probable prognosis and mortality risk of a patient with cirrhosis. The primary objective of this research is to observe the mortality risks of CLD caused by a variety of etiologies mentioned above. The secondary objective is to determine the biochemical markers that are correlating with the severity of the study groups. Another aim was to determine the Model for End-Stage Liver Disease (MELD) scoring of each study group predicting the severity of disease among the Child-Pugh classification.

Materials and methods

We broadly classified the etiologies into two study groups: (1) hepatitis B, C associated CLD (hepatitis B, C­-CLD) and (2) non-hepatitis B, C associated CLD (non-hepatitis B, C-CLD). This study was conducted as a descriptive, retrospective study involving patients admitted to the Gastroenterology Department at Dow University Hospital between July 2019 and December 2019. All patients who met the inclusion criteria were included in the study in order to document their levels of severity markers of CLD. A total of 167 individuals met the inclusion criteria, and the sampling was done through non-probability consecutive methods. All continuous variables were described as mean and standard deviations, which were then compared using an independent sample t-test. The comparison of categorical data was done either using the chi-square test or Fisher’s exact test accordingly. A p-value of <0.05 was considered statistically significant (two-tailed).

Results

The mean age of the study population was 51.83 ± 13.67, with no difference in gender and type of CLD. The frequent co-morbidities (other than CLD) found in the study population were diabetes, hypertension, ischemic heart disease, and chronic kidney disease, with most of them having significant association with non-hepatitis B, C-CLD. Both types of CLD had equal gender proportion (p=0.708). Among the study groups, 56.28% (n=94) had hepatitis B, C-CLD, out of which 18 (19%) belonged to Child-Pugh class A, 36 (38%) to Child-Pugh class B, and 40 (43%) to Child-Pugh class C, whereas 43.72% (n=71) had non-hepatitis B, C-CLD, comprising of 13% (n=10) of Child-Pugh class A patients, 42% (n=31) of Child-Pugh class B patients, and 44% (n=32) of Child-Pugh class C patients (p=0.631). Bilirubin levels (p=0.055), serum creatinine (p=0.201), and International normalized ratio (INR) are found higher in non-hepatitis B, C-CLD (p=0.312), whereas thrombocytopenia was more likely to be associated with hepatitis B, C-CLD (p=0.205). Hyponatremia was slightly associated with non-hepatitis B, C-CLD (p=0.281). The mean MELD score was comparable among the two study groups in both Child-Pugh classes A and B, but in Child-Pugh class C it was significantly higher in non-hepatitis B, C-CLD patients as compared to hepatitis B, C­-CLD (p=0.006).

Conclusion

Non-hepatitis B, C-CLD was proved to be milder in Child-Pugh class A as compared to hepatitis B, C-CLD, but its mortality risk increases with severity, as mean MELD score was found significantly higher in Child-Pugh class C. Our research was able to identify severe biochemical markers in both types of CLD.

Natural history of grade 1 ascites in patients with liver cirrhosis

Background

No evidence is available on the natural history of grade 1 ascites and its progression to grade 2/3 in patients with liver cirrhosis. The aim of the current study was to address this issue, to assess the development of main comorbid disorders closely related to ascites progression, and to identify the predictive factors for survival in this setting.

Methods

Consecutive Caucasian cirrhotic patients with grade 1 ascites were retrospectively analyzed. None of patients was under treatment with diuretics at diagnosis. Control groups consisted of 145 cirrhotics with grade 2/3 ascites and 175 cirrhotics without ascites.

Results

Diuretics were initiated in 58 patients with grade 1 ascites at baseline by the attending physician. At the last follow up, 29 patients had no ascites, 33 patients had grade 1 and 38 patients had grade 2/3 ascites. No variable was found to be an independent predictor of grade 2/3 ascites. Seven patients developed spontaneous bacterial peritonitis while under treatment with diuretics; at that time only 1 patient had grade 1 ascites. The mortality rate was similar among all examined groups.

Conclusions

This study suggests that the presence of grade 1 ascites does not constitute a precursor of grade 2/3 ascites in patients with cirrhosis. Thus, patients with grade 1 ascites do not require specific treatment with diuretics.

Early Multiplexed Detection of Cirrhosis using Giant Magnetoresistive Biosensors with Protein Biomarkers

Liver cirrhosis is one of the leading causes of death in adults worldwide. It is highly prevalent in developing countries and is growing in prevalence in developed countries mostly because of chronic liver diseases, such as chronic hepatitis B and C and alcoholic and nonalcoholic fatty liver disease. However, the prevalence of cirrhosis may be highly underestimated because early stages are asymptomatic and current early detection methods are inadequate. Here, we evaluate the potential of a set of novel cirrhotic protein biomarkers, including soluble intercellular adhesion molecule-1 and mac-2 binding protein glycosylation isomer, for early detection of cirrhosis in a multiplexed assay using our giant magnetoresistive (GMR) sensor arrays. We evaluated the diagnostic performance of the biomarkers, individually and in combination, using multivariate logistic regression and random forest in a blinded proof-of-concept retrospective case-controlled study. The biomarkers in combination exhibited high diagnostic performance in both logistic regression and random forest models, with an area under the curve of 0.98 (0.94-1.00). In addition, the combination of biomarkers resulted in a high sensitivity of 0.97 (0.95-1.00) and a high specificity of 1.00. We showed that the diagnostic performance of our novel set of cirrhotic protein biomarkers on our multiplexed GMR sensor arrays is higher than the performance of currently used clinical biomarkers and factors (i.e., age, sex, alanine aminotransferase, aspartate aminotransferase, etc.). With this combination of novel biomarkers and GMR technology, we could potentially boost the diagnostic power of early cirrhosis detection.

Dendritic Cell and T Cell Crosstalk in Liver Fibrogenesis and Hepatocarcinogenesis: Implications for Prevention and Therapy of Liver Cancer

Liver fibrosis is a chronic, highly prevalent disease that may progress to cirrhosis and substantially increases the risk for development of hepatocellular carcinoma (HCC). Fibrotic livers are characterized by an inflammatory microenvironment that is composed of various immunologically active cells, including liver-resident populations (e.g., Kupffer cells, hepatic stellate cells and sinusoidal endothelium) and infiltrating leukocytes (e.g., monocytes, monocyte-derived macrophages, neutrophils and lymphocytes). While inflammatory injury drives both fibrogenesis and carcinogenesis, the tolerogenic microenvironment of the liver conveys immunosuppressive effects that encourage tumor growth. An insufficient crosstalk between dendritic cells (DCs), the professional antigen presenting cells, and T cells, the efficient anti-tumor effector cells, is one of the main mechanisms of HCC tumor tolerance. The meticulous analysis of patient samples and mouse models of fibrosis-HCC provided in-depth insights into molecular mechanisms of immune interactions in liver cancer. The therapeutic modulation of this multifaceted immunological response, e.g., by inhibiting immune checkpoint molecules, in situ vaccination, oncolytic viruses or combinations thereof, is a rapidly evolving field that holds the potential to improve the outcome of patients with HCC. This review aims to highlight the current understanding of DC–T cell interactions in fibrogenesis and hepatocarcinogenesis and to illustrate the potentials and pitfalls of therapeutic clinical translation.

The many faces of cirrhosis

There are many different imaging features of cirrhosis, some of which are less commonly recognized. It is important that the radiologist is familiar with these features as cirrhosis can be first discovered on imaging performed for other indications, thus alerting the clinician for the need to screen for complications of cirrhosis and referral for potential treatment. This article reviews the various imaging findings of cirrhosis seen on cross-sectional imaging of the abdomen and pelvis.

[Evaluation of abnormal liver chemistries in primary care - A survey on the prerequisites, procedure and challenges faced by general practitioners]

Hintergrund  In der hausärztlichen Versorgung treten Leberwerterhöhungen als häufiger Zufallsbefund auf. Neben der Beachtung von Symptomen ist für eine effektive Abklärung entscheidend, welche Leberwerte als Indikatoren einbezogen und wann Patienten zur weiterführenden Diagnostik überwiesen werden. Ebenso kommt es auf eine geregelte Zusammenarbeit zwischen Haus- und Fachärzten an. Bislang fehlt es für den deutschsprachigen Raum an belastbaren Erkenntnissen über das Vorgehen und erlebte Herausforderungen von Hausärzten, wenn es um die Abklärung (unklarer) Leberwerterhöhungen geht.

Methodik  Im Zuge einer schriftlichen Befragung, die auf mehreren Vorstudien basiert, wurden zwischen Oktober 2019 und März 2020 insgesamt 2701 Hausärzte in Hessen und Baden-Württemberg zum Vorgehen bei Leberwerterhöhungen befragt. Neben der deskriptiven Analyse erfolgte eine Faktorenanalyse.

Ergebnisse  Die Ergebnisse zeigen für die Hausarztmedizin verschiedene Herausforderungen und Problematiken. Hinsichtlich der Beachtung von Warnzeichen sowie mit Blick auf die herangezogenen leberassoziierten Laborparameter sind stark unterschiedliche Cluster hausärztlichen Vorgehens auszumachen. Im Fall erhöhter Leberwerte präferiert eine Mehrheit der Befragten ein kontrolliertes Zuwarten (59 %), allerdings machen Hausärzte im Alltag oft von direkten Überweisungen zu Spezialisten Gebrauch (66 %). In der Zusammenarbeit mit gastroenterologischen Fachärzten bestehen aus hausärztlicher Sicht diverse Schnittstellenprobleme.

Diskussion  Es erscheint sinnvoll, Maßnahmen zu ergreifen, die zu einer verstärkten Professionalisierung und Vereinheitlichung der hausärztlichen Diagnostik beitragen und die Zusammenarbeit mit gastroenterologischen Spezialisten besser strukturieren. Dazu zählen etwa ein breiteres Angebot von Schulungs- und Fortbildungsformaten, die Entwicklung eines validierten Diagnose- und Behandlungspfads (v. a. Früherkennung von Patienten mit erhöhtem Risiko für eine Leberfibrose oder Leberzirrhose) oder die feste Verankerung einer leberwertassoziierten Blutuntersuchung im Rahmen des Check-ups. Der Entwicklung einer fundierten hausarztbasierten Leitlinie zur Erkennung und zum Umgang mit erhöhten Leberwerten sollte nachgegangen werden.

Thalidomide for the Treatment of Thrombocytopenia and Hypersplenism in Patients With Cirrhosis or Thalassemia

Hypersplenism and thrombocytopenia are common complications of liver cirrhosis or thalassemia, but current treatment strategies are limited. This study aimed to evaluate the efficacy and safety of thalidomide in the treatment of hypersplenism and thrombocytopenia in patients with liver cirrhosis or thalassemia. A total of 31 patients with hepatic cirrhosis (n=19) or thalassemia (n=12) diagnosed with hypersplenism and thrombocytopenia (platelet count [PLT] <100×10⁹/L) were included in this prospective cohort study between January 2015 and May 2017. Patients were treated with thalidomide (150-200 mg/d) plus conventional therapy. Spleen length, PLT, leukocyte count (WBC), absolute neutrophil count (ANC), and hemoglobin level (Hb) were measured at baseline, 3, 6, and 12 months. Any adverse events were noted. All of the 31 patients were showed a progressive increase PLT during the 12-month follow-up, and similar results were obtained when subgroup analyses were performed based on the primary disease (cirrhosis or thalassemia). WBC, ANC, and Hb also increased progressively during the 12-month follow-up. Spleen length decreased progressively during the follow-up. No serious adverse events occurred. Thalidomide is a potential treatment for thrombocytopenia caused by hypersplenism in patients with cirrhosis or thalassemia.

Differential fibrotic phenotypes of hepatic stellate cells within 3D liver organoids

Liver fibrosis occurs in most cases of chronic liver disease, which are somewhat common, but also a potentially deadly group of diseases. In vitro modeling of liver fibrosis relies primarily on the isolation of in vivo activated hepatic stellate cells (aHSCs) and studying them in standard tissue culture dishes (two-dimensional [2D]). In contrast, modeling of fibrosis in a biofabricated three-dimensional (3D) construct allows us to study changes to the environment, such as extracellular matrix (ECM) composition and structure, and tissue rigidity. In the current study, we used aHSCs produced through subcultures in 2D and encapsulated them in a 3D collagen gel to form spherical constructs. In parallel, and as a comparison, we used an established HSC line, LX-2, representing early and less severe fibrosis. Compared with LX-2 cells, the aHSCs created a stiffer environment and expressed higher levels of TIMP1 and LOXL2, all of which are indicative of advanced liver fibrosis. Collectively, this study presents a fibrosis model that could be incorporated with multi-cellular models to more accurately reflect the effects of a severe fibrotic environment on liver function.

Matrix Metalloproteinases as Potential Biomarkers and Therapeutic Targets in Liver Diseases

Chronic liver diseases, characterized by an excessive accumulation of extracellular matrix (ECM) resulting in scar tissue formation, are a growing health problem causing increasing morbidity and mortality worldwide. Currently, therapeutic options for tissue fibrosis are severely limited, and organ transplantation is the only treatment for the end-stage liver diseases. During liver damage, injured hepatocytes release proinflammatory factors resulting in the recruitment and activation of immune cells that activate quiescent hepatic stellate cells (HSCs). Upon activation, HSCs transdifferentiate into highly proliferative, migratory, contractile and ECM-producing myofibroblasts. The disrupted balance between ECM deposition and degradation leads to the formation of scar tissue referred to as fibrosis. This balance can be restored either by reducing ECM deposition (by inhibition of HSCs activation and proliferation) or enhancing ECM degradation (by increased expression of matrix metalloproteinases (MMPs)). MMPs play an important role in ECM remodeling and represent an interesting target for therapeutic drug discovery. In this review, we present the current knowledge about ECM remodeling and role of the different MMPs in liver diseases. MMP expression patterns in different stages of liver diseases have also been reviewed to determine their role as biomarkers. Finally, we highlight MMPs as promising therapeutic targets for the resolution of liver diseases.