Livers

Background/Objectives: The approval of direct-acting antiviral (DAA) therapy for hepatitis C (HCV) resulted in a highly effective oral treatment for patients. The primary objective of this study was to identify reasons that patients were not treated versus why patients were treated. Identifying potential reasons for the failure to treat can provide a pathway to interventions using evidence-based data. Methods: The electronic medical records in an urban predominately African American (AA) population were searched for all patients with HCV seen at least once in a Gastroenterology or Infectious Disease clinic in 2019. Data collected included demographics, treatment visits, laboratory data, insurance and ZIP codes for median income. Results: Of the 441 patients who were not yet treated at the first 2019 visit, only 43% were treated by July 2020. Insurance and median income were not factors in failure to treat. Patients with an average of four visits were more likely to be treated than those with two or less, suggesting that failure to follow up was a significant factor for patient treatment (42% vs. 8% p < 0.0001). Confirmation of viral infection at first visit was an important factor with respect to treatment (treated 38% vs. not treated 25% p < 0.02). Conclusions: Significant numbers of our patients (57%) failed to be treated after at least one clinic visit. The two critical factors were PCR confirmation prior to the initial visit and the requirement for multiple visits before the initiation of treatment. Since the degree of fibrosis had no impact on treatment, initiating treatment immediately after confirming infection with HCV should improve patient treatment rates and outcomes. Full article

Infection of hepatitis B (HBV) patients with hepatitis D (HDV) can cause the most severe form of viral hepatitis, leading to liver fibrosis, liver failure, and hepatocellular carcinoma. HDV relies on simultaneous infection with HBV for the generation of infectious viral particles. The innate immune response, which is weakly induced in HBV infection, becomes strongly activated upon HDV co-infection. In HBV/HDV co-infection, the immune system comprises a cell-intrinsic strong IFN response, which leads to the induction of interferon-stimulated genes (ISGs), the local activation of liver-resident innate immune cells, and additional immune cell recruitment from the blood. Efficient innate immune responses are indispensable for successful viral control and spontaneous viral clearance. Despite this fact, innate immune cell activation can also contribute to adaptive immune cell inhibition and accelerate liver damage in HBV/HDV infection. While the intrinsic IFN response in HDV-infected cells is well characterized, far less is known about the cellular innate immune cell compartment. In this review, we summarize HBV/HDV replication characteristics and decipher the role of innate immune cell subsets in the anti-viral response in HBV/HDV infections. We further review the impact of epigenetic and metabolic changes in infected heptatocytes on the innate anti-viral response. Moreover, we discuss the potential of exploiting the innate immune response for improving vaccination strategies and treatment options, which is also discussed in this review. Full article

Background: Pediatric hepatitis B virus (HBV) serostatus remains variably characterized, hardly determined at times, or documented as part of national monitoring of the Extended Programs for Immunization (EPI). Methods: We cross-sectionally characterized the seroprevalence of HBV vaccine and/or infection status among 501 and 288 children <5 and 15–17 years old, respectively, in Kawempe Division, Kampala, Uganda, between May and August 2023. These children received HBV vaccination under the Uganda National Extended Program on Immunizations (UNEPI). Samples were qualitatively screened for hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (HBsAb or anti-HBs), hepatitis B e antigen (HBeAg), hepatitis B e antibody (HBeAb or anti-HBe), and for hepatitis B core antibody (HBcAb or anti-HBc) using three different HBV Combo test rapid immunochromatographic diagnostic tests: Nova, Fastep, and Beright. Results: The seroprevalence of HBsAg, anti-HBs, HBeAg, anti-HBe, and anti-HBc was 1.52%, 27.75%, 0.88%, 0.63%, and 0.76%, respectively, for the combined study age groups. The HBsAg seroprevalence of 2.78% was almost 3.5-fold higher among adolescents when compared to the 0.8% observed in the under-5-year-olds. The qualitative seroprevalence of anti-HBs was 33.1% and 18.4% in the under-5 and among the 15–17-year-old study groups, respectively. Conclusions: The proportion of qualitatively detectable anti-HBs in both groups of vaccinated children is low and probably indicates reduced seroprotection. Consequently, a large proportion of children who received the hepatitis B vaccine under UNEPI may be at risk of HBV infection, especially adolescents. A booster dose of the Hepatitis B Vaccine may be required for adolescents. Full article

Hepatic steatosis is considered the hepatic manifestation of metabolic disorders. Its global prevalence is a growing public health concern, estimated to affect over 30% of the population. Steatosis is strictly linked to metabolic dysfunction, leading to the revised terminology of MASLD (metabolic dysfunction-associated steatotic liver disease). The disease often progresses in conjunction with metabolic syndrome components, significantly increasing cardiovascular and overall mortality risks. The interplay between sex hormones and metabolic dysfunction is crucial, with male hypogonadism and female hyperandrogenism exacerbating the risk and severity of hepatic steatosis. In men, testosterone deficiency is associated with increased visceral adiposity and insulin resistance, creating a vicious cycle of metabolic deterioration. Conversely, in women, hyperandrogenism, particularly in conditions like polycystic ovary syndrome, may lead to severe metabolic disturbances, including hepatic steatosis. Estrogen deficiency also contributes to central adiposity and metabolic syndrome. The aim of this paper is to discuss this complex sex-dimorphic relationship. Full article

Background: Creating a model for acute liver failure in animal models is essential for research on liver regeneration and cancer. Current surgical techniques allow for a maximum of 80% partial hepatectomy in rats, with low survival rates due to poor inflow control. The common resection technique involves ligation at the liver lobe neck, causing peri-operative blood loss and postoperative blood loss. Methods: A 90% partial hepatectomy was performed on 5 rats using a bile duct-saving portal ligation technique, involving two hilum dissections for bile duct preservation. The first dissection controlled the blood supply to the median and left lateral lobes, and the second to the right inferior and superior lobes. Before closing, all rats were given 5 mL of 10% dextrose intraperitoneally and had access to ClearH₂O DietGel Recovery and 20% dextrose. Weight and behavior were closely monitored for seven days post-operatively. Results: This method resulted in 100% survival, with a 3.1% increase in liver mass and 12.3% increase in liver-to-body mass ratio. Conclusions: This technique is the first bile duct-saving portal ligation for rodent models of acute liver failure, with long-term survival and complete hepatic regeneration. Our procedure offers a viable 90% hepatectomy model for research with improved survival and regeneration outcomes. Full article

Background/Objectives: Efforts to preoperatively risk stratify and optimize patients before liver resection allow for improvements in postoperative outcomes, with hypoalbuminemia being increasingly researched as a surrogate for nutrition, overall health and functional status. Given the paucity of studies examining the relationship between hypoalbuminemia and liver resection, this study aims to determine the impact of hypoalbuminemia on outcomes following liver resections using a large multicenter database. Methods: The American College of Surgeons–National Surgical Quality Improvement Program (2017–2021) database was used to extract the data of patients who underwent a hepatic resection. Two cohorts were defined; those with hypoalbuminemia (HA; <3.0 g/L) and those with normal albumin levels (≥3.0 g/L). Both baseline characteristics and 30-day postoperative complication rates were compared between the two cohorts. Multivariable logistic regression models were used to assess the independent effect of HA on various outcomes. Area under curve–receiver operating characteristic (AUC-ROC) curves were used to identify optimal albumin thresholds for both serious complications and mortality. Results: We evaluated 26,394 patients who underwent liver resections, with 1347 (5.1%) having preoperative HA. The HA patients were older (62.3 vs. 59.8; p < 0.001) and more likely to be of an ASA class ≥ 4 (13.0% vs. 6.5%; p < 0.001). The patients with HA had significantly more complications such as an increased length of stay, readmission, reoperation, sepsis, surgical site infection, bile leak, and need for transfusion. After controlling for demographics and comorbidities, HA remained a significant independent predictor associated with both 30-day serious complication rates (aOR 2.93 [CI 95% 2.36–3.65, p < 0.001]) and mortality (aOR 2.15 [CI 95% 1.38–3.36, p = 0.001]). The optimal cut-off for albumin with respect to predicting serious complications was 4.0 g/dL (sensitivity 59.1%, specificity 56.8%, AUC-ROC 0.61) and 3.8 g/dL (sensitivity 56.6%, specificity 68.3%, AUC-ROC 0.67) for mortality. Conclusions: In this large, retrospective database analysis, preoperative HA was significantly associated with 30-day morbidity and mortality rates following hepatic resection. Preoperative albumin may serve as a useful marker for risk stratification in conjunction with pre-existing calculators. Future studies evaluating the risk mitigation impact of nutrition and exercise prehabilitation in these patients and its capacity to modify hypoalbuminemia would be beneficial. Full article

The primary objective of modern medicine is to extend human life expectancy. Currently, the majority of hospital patients across various clinical settings are elderly or advanced-age individuals, often with multiple comorbidities and age-related alterations in peripheral tissues. One such alteration is sarcopenia, a progressive decline in muscle mass, strength, and function, which significantly increases the risk of disability and mortality in older adults. Sarcopenia is associated with numerous adverse outcomes, and its underlying mechanisms are the subject of ongoing research. This narrative review discusses the epidemiology, pathophysiology, and diagnostic criteria for sarcopenia. It also examines the connections between sarcopenia and metabolic dysfunction-associated steatotic liver disease (MASLD), highlighting potential treatment approaches for the coexistence of these two pathologies. Full article

Intestinal mucus serves as the first line barrier within the mucosa to protect against microbiota attack due to its water-repellent properties, which are the result of the high abundance of phosphatidylcholine bound to mucins. A deficiency of mucus phosphatidylcholine predisposes it to mucosal inflammation by the attack of commensal microbiota, as it is intrinsically low in ulcerative colitis. However, for precipitation of an acute inflammatory episode, mucus phosphatidylcholine has to fall below the critical level required for mucosal protection. Bacterial ectophospholipase could be a candidate for further thinning of the mucus phosphatidylcholine shield as shown, for example, with the ectophospholipase containing Helicobacter pylori bacterium. Despite supporting evidence for this mechanism in the intestine, the responsible ectophospholipase-carrying bacteria species are still to be defined. Applying phosphatidylcholine to the lumen can serve to fill up empty mucin-binding sites in ulcerative colitis as well as provide a substrate for the ectophospholipase-carrying bacteria preventing their attacks on the mucus phosphatidylcholine layer. Evidence supporting this concept comes from clinical trials in humans with ulcerative colitis as well as from colitis mouse models where phosphatidylcholine was substituted in the lumen. An alternative strategy could involve adding non-absorbable phospholipase inhibitors to the intestinal lumen, which has been shown to be effective in a mouse model of ulcerative colitis. Bacterial phospholipase should be considered a pathogenetic factor of the intestinal microbiota and therapeutic strategies should be developed to prevent their hyperactivity for clinical improvement of intestinal inflammation. Full article

Metabolic dysfunction-associated steatotic liver disease (MASLD) encompasses metabolic dysfunction-associated fatty liver (MASL) and metabolic dysfunction-associated steatohepatitis (MASH), with MASH posing a risk of progression to cirrhosis and hepatocellular carcinoma (HCC). The global prevalence of MASLD is estimated at approximately a quarter of the population, with significant healthcare costs and implications for liver transplantation. The pathogenesis of MASLD involves intrahepatic liver cells, extrahepatic components, and immunological aspects, particularly the involvement of macrophages. Hepatic macrophages are a crucial cellular component of the liver and play important roles in liver function, contributing significantly to tissue homeostasis and swift responses during pathophysiological conditions. Recent advancements in technology have revealed the remarkable heterogeneity and plasticity of hepatic macrophage populations and their activation states in MASLD, challenging traditional classification methods like the M1/M2 paradigm and highlighting the coexistence of harmful and beneficial macrophage phenotypes that are dynamically regulated during MASLD progression. This complexity underscores the importance of considering macrophage heterogeneity in therapeutic targeting strategies, including their distinct ontogeny and functional phenotypes. This review provides an overview of macrophage involvement in MASLD progression, combining traditional paradigms with recent insights from single-cell analysis and spatial dynamics. It also addresses unresolved questions and challenges in this area. Full article

Non-alcoholic fatty liver disease (NAFLD) has emerged as a significant global health issue. The condition is closely linked to metabolic dysfunctions such as obesity and type 2 diabetes. The gut–liver axis, a bidirectional communication pathway between the liver and the gut, plays a crucial role in the pathogenesis of NAFLD. This review delves into the mechanisms underlying the gut–liver axis, exploring the influence of gut microbiota, intestinal permeability, and inflammatory pathways. This review also explores the potential therapeutic strategies centered on modulating gut microbiota such as fecal microbiota transplantation; phage therapy; and the use of specific probiotics, prebiotics, and postbiotics in managing NAFLD. By understanding these interactions, we can better comprehend the development and advancement of NAFLD and identify potential therapeutic targets. Full article

Liver transplantation is the most effective treatment for end-stage liver disease. Despite improvements in surgical techniques, transplant rejection remains a significant concern. The liver is considered an immune-privileged organ due to its unique microenvironment and complex interactions among various cell types. Alloimmune responses mediated by T cells and antigen-presenting cells (APCs) play crucial roles in transplant rejection. The liver’s dual blood supply and unique composition of its sinusoidal endothelial cells (LSECs), Kupffer cells (KCs), hepatocytes, and hepatic stellate cells (HSCs) contribute to its immune privilege. Alloantigen recognition by T cells occurs through direct, indirect, and semidirect pathways, leading to acute cellular rejection (ACR) and chronic rejection. ACR is a T cell-mediated process that typically occurs within the first few weeks to months after transplantation. Chronic rejection, on the other hand, is a gradual process characterized by progressive fibrosis and graft dysfunction, often leading to graft loss. Acute antibody-mediated rejection (AMR) is less common following surgery compared to other solid organ transplants due to the liver’s unique anatomy and immune privilege. However, when it does occur, AMR can be aggressive and lead to rapid graft dysfunction. Despite improvements in immunosuppression, rejection remains a challenge, particularly chronic rejection. Understanding the mechanisms of rejection and immune tolerance, including the roles of regulatory T cells (Tregs) and hepatic dendritic cells (DCs), is crucial for improving transplant outcomes. Strategies to induce immune tolerance, such as modulating DC function or promoting Treg activity, hold promise for reducing rejection and improving long-term graft survival. This review focuses on the liver’s unique predisposition to rejection and tolerance, highlighting the roles of individual cell types in these processes. Continued research into the mechanisms of alloimmune responses and immune tolerance in liver transplantation is essential for developing more effective therapies and improving long-term outcomes for patients with end-stage liver disease. Full article

Cell-death-inducing DNA fragmentation factor-alpha (DFFA)-like effector b (CIDEB) was first identified as an apoptosis-inducing protein. Further research revealed a pivotal role in lipid metabolism, regulating very-low-density lipoprotein (VLDL), lipid droplets (LD), sterol response element-binding protein (SREBP), and chylomicrons. Recent studies have uncovered that rare germline variants in CIDEB protect against liver diseases, including MAFLD, cirrhosis, and viral hepatitis. Furthermore, CIDEB influences steps of the hepatitis C virus (HCV) replication cycle. This review summarizes the current knowledge about CIDEB’s roles in apoptosis, lipid metabolism, and viral hepatitis, and highlights its critical role in liver diseases. Full article

Fibrolamellar hepatocellular carcinoma (FL-HCC) is a malignant primary hepatic cancer that affects mainly adolescents and young adults without underlying liver disease. Its biology remains unknown, but it is pathologically distinct from traditional HCC. Therapeutic strategies are not well defined and, as chemotherapies seem to have limited efficacy, surgical resection remains the only effective treatment. Here we report on a case of a metastatic FL-HCC in an 18-year-old man successfully treated with aggressive intra-thoracic bilateral lung metastasectomy following primary tumour resection and adjuvant chemotherapy. Survival time after initial hepatectomy is 39 months, with no recurrence of disease to date. Aggressive surgical resection and redo surgery should be considered until more effective multimodality therapies are identified. Multidisciplinary team discussion and involvement of medical and surgical specialties are essential in managing these rare entities. Full article

Hepatitis delta virus (HDV) infection is the most severe form of viral hepatitis. Genotype 1 (HDV-1) is by far the most prevalent in Europe and globally, while HDV-5 predominates in Western Africa. Data about HDV seroprevalence in Portugal are scarce and genotyping studies have not been performed yet. We aimed to assess the seroprevalence and genotypes of HDV in a large cohort of HBsAg-positive patients followed in our Hepatology Unit between 2012 and 2022. The anti-HDV-positive patients were subjected to a cross-sectional analysis, including blood sample collection for HDV RNA testing and genotype determination. In the cohort of HBsAg-positive patients, 57.5% (480/835) were born in African countries and 665/835 (79.6%) had been screened for anti-HDV antibodies. The HDV seroprevalence obtained was 6.5% (43/665). Twenty-one patients (age 41.2 ± 9.9 years; 57.1% male) were included in further molecular analyses. HDV RNA was positive in 8/21 (38.0%) and classified as HDV-5 in 7 patients (6 from Guinea-Bissau and 1 from Cape Verde) and HDV-1 in 1 patient (from Ukraine). In the largest and most comprehensive study performed in Portugal regarding HDV epidemiology to date, seroprevalence and genotype distribution of HDV (with predominance of HDV-5) were strongly influenced by immigration, notably from African countries. Full article

Acetaminophen (APAP) overdose can induce hepatocyte necrosis and acute liver failure in experimental rodents and humans. APAP is mainly metabolized via hepatic cytochrome P450 enzymes to generate the highly reactive metabolite N-acetyl-p-benzoquinone imine (NAPQI), which forms acetaminophen protein adducts (APAP-adducts) and damages mitochondria, triggering necrosis. APAP-adducts and damaged mitochondria can be selectively removed by autophagy. Increasing evidence implies that the activation of autophagy may be beneficial for APAP-induced liver injury (AILI). In this minireview, we briefly summarize recent progress on autophagy, in particular, the pharmacological targeting of SQSTM1/p62 and TFEB in AILI. Full article

The preS1 region of the large hepatitis B virus (HBV) surface protein is a crucial component in HBV infection; however, its impact on the development of hepatocellular carcinoma (HCC) remains unknown. This study investigated the relationship between serum preS1 levels and hepatocarcinogenesis in patients with chronic hepatitis B (CHB). The preS1 levels were measured in 531 patients with CHB without a history of HCC. Among the patients, 293 HBV carriers who had never received nucleotide/nucleoside analog (NA) therapy had their preS1 levels measured at their first visit (non-NA group), and 238 patients who had received NA therapy had their preS1 levels measured at the start of NA administration (NA group). The two groups had no significant differences in hepatitis B surface antigen (HBsAg) levels; however, the NA group’s preS1/HBsAg ratio was significantly higher. The preS1/HBsAg ratio was significantly different between patients with CHB not meeting the NA treatment criteria and patients with chronic hepatitis and cirrhosis who were eligible for NA treatment. The predictors of HCC development were analyzed, and the preS1/HBsAg ratio was identified in both groups. The preS1/HBsAg ratio could predict hepatocarcinogenesis in patients with CHB with or without NA administration. Full article

To clarify the risk factors for the aggravation of esophagogastric varices (EGVs) after hepatitis C virus (HCV) eradication with direct-acting antiviral (DAA) therapy, we enrolled 167 consecutive patients with HCV-related compensated cirrhosis who achieved a sustained virological response (SVR) after DAA therapy. During a median of 69 months, EGVs were aggravated in 42 (25%) patients despite SVR. The cumulative 1-, 3-, 5-, and 10-year aggravated EGV rates were 7%, 23%, 25%, and 27%, respectively. Multivariate analysis identified a platelet count < 11.0 × 10⁴/μL, LSM ≥ 18.0 kPa, total bile acid ≥ 33.0 μmol/L, and a diameter of left gastric vein (LGV) ≥ 5.0 mm at HCV eradication as independent risk factors for EGV aggravation post-SVR. In groups that met all of these risks, the cumulative EGV aggravation rates at 1, 3, and 5 years were 27%, 87%, and 91%, respectively. However, none of the patients who had only one or none of the risk factors experienced EGV aggravation. Platelet count, LSM, total bile acid, and diameter of LGV at HCV eradication were associated with aggravated EGV post-SVR. EGVs tend to worsen as two or more of these risk factors increase. Full article

Overdose of acetaminophen (APAP) produces fulminant hepatic necrosis. The underlying mechanism of APAP hepatotoxicity involves mitochondrial dysfunction, including mitochondrial oxidant stress and the onset of mitochondrial permeability transition (MPT). Reactive oxygen species (ROS) play an important role in APAP-induced hepatotoxicity, and iron is a critical catalyst for ROS formation. This review summarizes the role of mitochondrial ROS formation in APAP hepatotoxicity and further focuses on the role of iron. Normally, hepatocytes take up Fe³⁺-transferrin bound to transferrin receptors via endocytosis. Concentrated into lysosomes, the controlled release of iron is required for the mitochondrial biosynthesis of heme and non-heme iron-sulfur clusters. After APAP overdose, the toxic metabolite, NAPQI, damages lysosomes, causing excess iron release and the mitochondrial uptake of Fe²⁺ by the mitochondrial calcium uniporter (MCU). NAPQI also inhibits mitochondrial respiration to promote ROS formation, including H₂O₂, with which Fe²⁺ reacts to form highly reactive •OH through the Fenton reaction. •OH, in turn, causes lipid peroxidation, the formation of toxic aldehydes, induction of the MPT, and ultimately, cell death. Fe²⁺ also facilitates protein nitration. Targeting pathways of mitochondrial iron movement and consequent iron-dependent mitochondrial ROS formation is a promising strategy to intervene against APAP hepatotoxicity in a clinical setting. Full article

Segmental or lobar liver atrophy is a common but not well-understood clinical condition. Hepatic atrophy can be classified into hepatic atrophy secondary to other pathologies and primary segmental hepatic atrophy, which is a benign intrahepatic lesion (pseudotumor) not associated with any other pathology. The pathophysiological mechanisms underlying atrophy can be divided into three main situations: obstruction of biliary outflow, obstruction of the systemic venous outflow, and obstruction of incoming portal venous flow. For what may concern secondary hepatic atrophy, there are many pathologies that could underlie this condition, ranging from benign to intrahepatic malignancies, with particular reference to particularly hepatocellular carcinoma and biliary duct carcinoma. An accurate and prompt differential diagnosis between the various forms and causes of atrophy is important for early identification and adequate treatment of underlying pathologies. A comprehensive review of the literature on the etiology and the radiological and histological characteristics of different types of hepatic atrophy is currently unavailable. Therefore, the aim of this review is to summarize the primary and secondary causes of segmental or lobar liver atrophy (excluding forms involving the entire liver parenchyma) and to provide practical tools for clinical and radiological differential diagnosis. Full article