Critical Care Management of Acute-on-Chronic Liver Failure: Certainties and Unknowns.

Intensive care unit (ICU) admission is frequently required in patients with decompensated cirrhosis for organ support. This entity, known as acute-on-chronic liver failure (ACLF), is associated with high short-term mortality. ICU management of ACLF is complex, as these patients are prone to develop new organ failures and infectious or bleeding complications. Poor nutritional status, lack of effective liver support systems, and shortage of liver donors are also factors that contribute to increase their mortality. ICU therapy parallels that applied in the general ICU population in some complications but has differential characteristics in others. This review describes the current knowledge on critical care management of patients with ACLF including organ support, prognostic assessment, early liver transplantation, and futility rules. Certainties and knowledge gaps in this area are also discussed.

Urinary L-FABP is a promising prognostic biomarker of ACLF and mortality in patients with decompensated cirrhosis.

BACKGROUND & AIMS: Decompensated cirrhosis (DC) is associated with high mortality, mainly owing to the development of acute-on-chronic liver failure (ACLF). Identifying the patients with DC who are at high risk of mortality and ACLF development is an unmet clinical need. Liver fatty acid-binding protein (L-FABP) is expressed in several organs and correlates with liver and systemic inflammation. Herein, we aimed to assess the prognostic value of L-FABP in patients with DC. METHODS: A prospective series of 444 patients hospitalized for DC was divided into 2 cohorts: study cohort (305 patients) and validation cohort (139 patients). L-FABP was measured in urine and plasma samples collected at admission. Neutrophil gelatinase-associated lipocalin (NGAL) was also measured in urine samples for comparison. RESULTS: Urine but not plasma L-FABP correlated with 3-month survival on univariate analysis. On multivariate analysis, urine L-FABP and model for end-stage liver disease (MELD)-Na were the only independent predictors of prognosis. Urine L-FABP levels were higher in patients with ACLF than in those without and also predicted the development of ACLF, together with MELD-Na, during follow-up. In patients with ACLF, urine L-FABP correlated with liver, coagulation, and circulatory failure. Urine L-FABP levels were also increased in patients with acute kidney injury, particularly in those with acute tubular necrosis. The ability of urinary L-FABP to predict survival and ACLF development was confirmed in the validation cohort. Urine NGAL predicted outcome on univariate but not multivariate analysis. CONCLUSIONS: Urinary L-FABP levels are independently associated with the 3-month clinical course in patients with DC, in terms of mortality and ACLF development. Urinary L-FABP is a promising prognostic biomarker for patients with DC. LAY SUMMARY: Increased levels of liver fatty acid-binding protein (L-FABP), a protein related to lipid metabolism, have been associated with liver-related diseases. The present study analyzed urinary L-FABP levels in 2 independent groups of patients with decompensated cirrhosis and showed that higher urinary L-FABP levels correlated with increased mortality and risk of acute-on-chronic liver failure development. Therefore, urinary L-FABP levels could be useful as a new tool to predict complications in patients with decompensated cirrhosis.

Rectal colonization by resistant bacteria increases the risk of infection by the colonizing strain in critically ill patients with cirrhosis.

BACKGROUND & AIMS: It remains unclear whether rectal colonization with multidrug-resistant organisms (MDROs) is prevalent and predisposes to infections by the same pathogens in patients with cirrhosis. METHODS: Two series of critically ill patients were evaluated. In the Barcelona cohort, 486 consecutive patients were prospectively evaluated, 129 with and 357 without cirrhosis (2015-2016). Rectal swabs were performed at admission and weekly thereafter (until intensive care unit [ICU] discharge) to detect MDRO colonization. Risk factors for colonization and infection by MDROs were evaluated. A retrospective cohort from Frankfurt (421 patients with cirrhosis; 2010-2018) was investigated to evaluate MDRO rectal colonization in another epidemiological scenario. RESULTS: In the Barcelona cohort, 159 patients were colonized by MDROs (32.7%), 102 (64.2%) at admission and 57 (35.8%) during follow-up. Patients with cirrhosis showed higher rates of rectal colonization at admission than those without cirrhosis (28.7% vs. 18.2%, p = 0.01) but similar colonization rates during ICU stay. Extended-spectrum beta-lactamase-Enterobacterales were the most frequent MDROs isolated in both groups. Colonization by MDROs independently increased the risk of infection by MDROs at admission and during follow-up. Risk of new infection by the colonizing strain was also significantly increased in patients with (hazard ratio [HR] 7.41) and without (HR 5.65) cirrhosis. Rectal colonization by MDROs was also highly prevalent in Frankfurt (n = 198; 47%; 131 at admission [66.2%] and 67 [33.8%] during follow-up), with vancomycin-resistant enterococci being the most frequent colonizing organism. Rectal colonization by MDROs was also associated with an increased risk of infection by MDROs in this cohort. Infections occurring in MDR carriers were mainly caused by the colonizing strain. CONCLUSION: Rectal colonization by MDROs is extremely frequent in critically ill patients with cirrhosis. Colonization increases the risk of infection by the colonizing resistant strain. LAY SUMMARY: Rectal colonization by multidrug-resistant organisms (MDROs) is a prevalent problem in patients with cirrhosis requiring critical care. The pattern of colonizing bacteria is heterogeneous with relevant differences between centers. Colonization by MDROs is associated with increased risk of infection by the colonizing bacteria in the short term. This finding suggests that colonization data could be used to guide empirical antibiotic therapy and de-escalation policies in patients with cirrhosis.

Decompensation in Advanced Nonalcoholic Fatty Liver Disease May Occur at Lower Hepatic Venous Pressure Gradient Levels Than in Patients With Viral Disease.

BACKGROUND & AIMS: Portal hypertension is the strongest predictor of hepatic decompensation and death in patients with cirrhosis. However, its discriminatory accuracy in patients with nonalcoholic fatty liver disease (NAFLD) has been challenged because hepatic vein catheterization may not reflect the real portal vein pressure as accurately as in patients with other etiologies. We aimed to evaluate the relationship between hepatic venous pressure gradient (HVPG) and presence of portal hypertension-related decompensation in patients with advanced NAFLD (aNAFLD). METHODS: Multicenter cross-sectional study included 548 patients with aNAFLD and 444 with advanced RNA-positive hepatitis C (aHCV) who had detailed portal hypertension evaluation (HVPG measurement, gastroscopy, and abdominal imaging). We examined the relationship between etiology, HVPG, and decompensation by logistic regression models. We also compared the proportions of compensated/decompensated patients at different HVPG levels. RESULTS: Both cohorts, aNAFLD and aHVC, had similar baseline age, gender, Child-Pugh score, and Model for End-Stage Liver Disease score. Median HVPG was lower in the aNAFLD cohort (13 vs 15 mmHg) despite similar liver function and higher rates of decompensation in aNAFLD group (32% vs 25%; P = .019) than in the aHCV group. For any of the HVPG cutoff analyzed (<10, 10-12, or 12 mmHg) the prevalence of decompensation was higher in the aNAFLD group than in the aHCV group. CONCLUSIONS: Patients with aNAFLD have higher prevalence of portal hypertension-related decompensation at any value of HVPG as compared with aHCV patients. Longitudinal studies aiming to identify HVPG thresholds able to predict decompensation and long-term outcomes in aNAFLD population are strongly needed.

Agreement between wedged hepatic venous pressure and portal pressure in non-alcoholic steatohepatitis-related cirrhosis.

BACKGROUND & AIMS: Wedge hepatic vein pressure (WHVP) accurately estimates portal pressure (PP) in alcohol- or viral hepatitis-related cirrhosis. Whether this also holds true in cirrhosis caused by non-alcoholic steatohepatitis (NASH) is unknown. We aimed to evaluate the agreement between WHVP and PP in patients with NASH cirrhosis in comparison to patients with alcohol- or HCV-related cirrhosis. METHODS: All consecutive patients with NASH cirrhosis treated with a transjugular intrahepatic portosystemic shunt (TIPS) in 3 European centres were included (NASH group; n = 40) and matched with 2 controls (1 with alcohol-related and 1 with HCV-related cirrhosis) treated with TIPS contemporaneously (control group; n = 80). Agreement was assessed by Pearson's correlation (R), intra-class correlation coefficient (ICC), and Bland-Altman method. Disagreement between WHVP and PP occurred when both pressures differed by >10% of PP value. A binary logistic regression analysis was performed to identify factors associated with this disagreement. RESULTS: Correlation between WHVP and PP was excellent in the control group (R 0.92; p <0.001; ICC 0.96; p <0.001) and moderate in the NASH group (R 0.61; p <0.001; ICC 0.74; p <0.001). Disagreement between WHVP and PP was more frequent in the NASH group (37.5% vs. 14%; p = 0.003) and was mainly because of PP underestimation. In uni- and multivariate analyses, only NASH aetiology was associated with disagreement between WHVP and PP (odds ratio 4.03; 95% CI 1.60-10.15; p = 0.003). CONCLUSIONS: In patients with decompensated NASH cirrhosis, WHVP does not estimate PP as accurately as in patients with alcohol- or HCV-related cirrhosis, mainly because of PP underestimation. Further studies aimed to assess this agreement in patients with compensated NASH cirrhosis are needed. LAY SUMMARY: Portal pressure is usually assessed by measuring wedge hepatic vein pressure because of solid evidence demonstrating their excellent agreement in alcohol- and viral hepatitis-related cirrhosis. Our results show that in patients with decompensated cirrhosis caused by non-alcoholic steatohepatitis, wedge hepatic vein pressure estimates portal pressure with less accuracy than in patients with other aetiologies of cirrhosis, mainly because of portal pressure underestimation.

Sequential changes in urinary biomarker levels in patients with cirrhosis and severe hepatorenal syndrome.

Whether tubular injury develops in patients with acute kidney injury owing to hepatorenal syndrome (AKI-HRS) is controversial. We performed repeated measurements of biomarkers of tubular injury during a 14-day period in 60 patients with cirrhosis and AKI (34 with AKI-HRS meeting the classical definition of type 1 HRS and 26 with AKI owing to acute tubular necrosis, AKI-ATN). Nineteen of 34 patients had resolution of AKI-HRS, while the remainder had persistent AKI-HRS. The persistence of AKI-HRS was associated with remarkably high short-term mortality. There were no significant differences in urinary NGAL or IL-18 between patients with resolution vs those with persistent AKI-HRS throughout the 14-day period. By contrast, biomarker levels were significantly lower in AKI-HRS, even if persistent, compared to AKI-ATN. These findings are highly suggestive of lack of significant tubular injury in AKI-HRS and could be of value in the clinical decision between combined liver-kidney or liver transplantation alone in patients with cirrhosis and AKI candidates to transplantation.

Development of chronic kidney disease after acute kidney injury in patients with cirrhosis is common and impairs clinical outcomes.

BACKGROUND & AIMS: Acute kidney injury (AKI) is common in cirrhosis and is associated with poor prognosis. In patients who survive after AKI, it is not known whether the acute injury leads to chronic impairment of kidney function (chronic kidney disease [CKD]). The aim of the study was to determine the frequency of CKD at 3 months after an AKI episode and its effects on patient outcomes. METHODS: Patients admitted for complications of cirrhosis during a 6.5-year period were evaluated using the same protocol, with assessment of kidney function at regular intervals during and after hospitalization. CKD was defined as estimated glomerular filtration rate (eGFR) <60 ml/min/1.73m2 at 3 months after AKI. RESULTS: A total of 409 patients (168 with AKI and 241 without AKI) were included. After 3 months, 97 patients with AKI and 188 patients without AKI had survived. Of the 97 patients with AKI, 24 had developed CKD at 3 months compared to only 2 of the 188 patients without AKI (25% vs. 1%, odds ratio 31; p <0.0001). Risk factors independently associated with CKD were nosocomial AKI and severity of AKI (stage ≥1B). At diagnosis of CKD, all patients had stage 3A CKD and one-quarter of them progressed to stages 3B and 4 after 1 year. The transition from AKI to CKD was associated with an increased rate of 3-month hospital readmission, increased frequency of AKI, bacterial infections, ascites, and refractory ascites and a trend towards a higher need for liver transplantation. Transplant-free survival was not impaired. CONCLUSIONS: CKD frequently develops in patients with cirrhosis who survive AKI and has a negative impact on relevant clinical outcomes. The transition from AKI to CKD is common and should be considered a high-risk condition in patients with cirrhosis. LAY SUMMARY: Episodes of acute impairment of kidney function are common in patients with cirrhosis. This study shows that the development of chronic impairment of kidney function is frequent in patients surviving these acute episodes and that it is associated with a higher risk of developing other complications of cirrhosis and to a higher rate of 3-month hospital readmissions.

Plasma Exchange: An Effective Rescue Therapy in Critically Ill Patients With Coronavirus Disease 2019 Infection.

OBJECTIVES: Infection by severe acute respiratory syndrome coronavirus-2 can induce uncontrolled systemic inflammation and multiple organ failure. The aim of this study was to evaluate if plasma exchange, through the removal of circulating mediators, can be used as rescue therapy in these patients. DESIGN: Single center case series. SETTING: Local study. SUBJECTS: Four critically ill adults with coronavirus disease 19 pneumonia that failed conventional interventions. INTERVENTIONS: Plasma exchange. Two to six sessions (1.2 plasma volumes). Human albumin (5%) was used as the main replacement fluid. Fresh frozen plasma and immunoglobulins were administered after each session to avoid coagulopathy and hypogammaglobulinemia. MEASUREMENTS AND MAIN RESULTS: Serum markers of inflammation and macrophage activation. All patients showed a dramatic reduction in inflammatory markers, including the main cytokines, and improved severity scores after plasma exchange. All survived to ICU admission. CONCLUSIONS: Plasma exchange mitigates cytokine storm, reverses organ failure, and could improve survival in critically ill patients with coronavirus disease 2019 infection.

Neutrophil Gelatinase-Associated Lipocalin for Assessment of Acute Kidney Injury in Cirrhosis: A Prospective Study.

Kidney biomarkers appear to be useful in differential diagnosis between acute tubular necrosis (ATN) and other types of acute kidney injury (AKI) in cirrhosis, particularly hepatorenal syndrome (HRS-AKI). Distinction is important because treatment is different. However, kidney biomarkers are still not used in clinical practice. The aim of the current study was to investigate the accuracy of several biomarkers in differential diagnosis of AKI and in predicting kidney outcome and patient survival. This was a prospective study of 320 consecutive cases of AKI in patients hospitalized for decompensated cirrhosis. Evaluation of AKI was made with a diagnostic algorithm that included identification and removal/treatment of precipitating factors and albumin administration (1 g/kg for 2 days) to patients with AKI stage 1B or greater. Urinary neutrophil gelatinase-associated lipocalin (NGAL), monomeric NGAL (mNGAL), interleukin-18, and standard biomarkers were measured at diagnosis and on days 3, 7, and 14. Of the 320 cases, 153 were hypovolemia-induced AKI (48%), 93 were HRS-AKI (29%), 39 were ATN (12%), and 35 were due to miscellaneous causes (11%). Among all biomarkers, urinary NGAL measured at day 3 had the greatest accuracy for differential diagnosis between ATN and other types of AKI (area under the receiver operating characteristic curve, 0.87; 95% confidence interval, 0.78-0.95). The cutoff with the best predictive accuracy for ATN diagnosis was 220 µg/g creatinine. Progression of AKI during hospitalization was associated with persistently high NGAL levels, and NGAL was an independent predictive factor of AKI progression. Likewise, NGAL was also an independent predictive factor of 28-day mortality together with Model for End-Stage Liver Disease score. Conclusion: These results support the use of NGAL in clinical practice within the context of a diagnostic algorithm for differential diagnosis of AKI and outcome prediction in cirrhosis.

Acute liver failure: A practical update.

Acute liver failure is a rare and dynamic condition, with a broad aetiology and an incompletely understood pathophysiology. Management of this life-threatening disease requires critical care and organ support and frequently early liver transplantation. Proper identification, prevention and treatment of complications such as intracranial hypertension and sepsis are critical to optimising outcomes. The identification of the cause of acute liver failure and the prompt initiation of the aetiological treatment can also improve prognosis. Survival has progressively improved in parallel to advances in medical treatment. Intracranial hypertension complicating hepatic encephalopathy is less frequent than in the past and intracranial pressure monitoring now relies on non-invasive techniques. Current prognostic models have good accuracy to identify patients who will die without liver transplantation but are not able to identify those in whom transplantation is futile. New prognostic markers to select patients for transplantation are still in the pipeline. Therapeutic plasma exchange and, in some centers, early renal replacement therapy are well established treatments for the disease. The use of other artificial liver devices in clinical practice is not supported by evidence. This review is intended to provide a clinical update on the management of acute liver failure, incorporating the most recent advances in the field.

Therapeutic targeting of adipose tissue macrophages ameliorates liver fibrosis in non-alcoholic fatty liver disease.

Background & Aims: : The accumulation of adipose tissue macrophages (ATMs) in obesity has been associated with hepatic injury. However, the contribution of ATMs to hepatic fibrosis in non-alcoholic fatty liver disease (NAFLD) remains to be elucidated. Herein, we investigate the relationship between ATMs and liver fibrosis in patients with patients with NAFLD and evaluate the impact of modulation of ATMs over hepatic fibrosis in an experimental non-alcoholic steatohepatitis (NASH) model. Methods: Adipose tissue and liver biopsies from 42 patients with NAFLD with different fibrosis stages were collected. ATMs were characterised by immunohistochemistry and flow cytometry and the correlation between ATMs and liver fibrosis stages was assessed. Selective modulation of the ATM phenotype was achieved by i.p. administration of dextran coupled with dexamethasone in diet-induced obesity and NASH murine models. Chronic administration effects were evaluated by histology and gene expression analysis in adipose tissue and liver samples. In vitro crosstalk between human ATMs and hepatic stellate cells (HSCs) and liver spheroids was performed. Results: Patients with NAFLD presented an increased accumulation of pro-inflammatory ATMs that correlated with hepatic fibrosis. Long-term modulation of ATMs significantly reduced pro-inflammatory phenotype and ameliorated adipose tissue inflammation. Moreover, ATMs modulation was associated with an improvement in steatosis and hepatic inflammation and significantly reduced fibrosis progression in an experimental NASH model. In vitro, the reduction of the pro-inflammatory phenotype of human ATMs with dextran-dexamethasone treatment reduced the secretion of inflammatory chemokines and directly attenuated the pro-fibrogenic response in HSCs and liver spheroids. Conclusions: Pro-inflammatory ATMs increase in parallel with fibrosis degree in patients with NAFLD and their modulation in an experimental NASH model improves liver fibrosis, uncovering the potential of ATMs as a therapeutic target to mitigate liver fibrosis in NAFLD. Impact and implications: We report that human adipose tissue pro-inflammatory macrophages correlate with hepatic fibrosis in non-alcoholic fatty liver disease (NAFLD). Furthermore, the modulation of adipose tissue macrophages (ATMs) by dextran-nanocarrier conjugated with dexamethasone shifts the pro-inflammatory phenotype of ATMs to an anti-inflammatory phenotype in an experimental murine model of non-alcoholic steatohepatitis. This shift ameliorates adipose tissue inflammation, hepatic inflammation, and fibrosis. Our results highlight the relevance of adipose tissue in NAFLD pathophysiology and unveil ATMs as a potential target for NAFLD.

Impact of the COVID-19 pandemic on the care and outcomes of people with NAFLD-related cirrhosis.

Background & Aims: The COVID-19 pandemic has had a major negative impact on health systems and many chronic diseases globally. We aimed to evaluate the impact of the first year of the pandemic on the outcomes of people with NAFLD cirrhosis. Methods: We conducted a before-after study in four University hospitals in Catalonia, Spain. Study subperiods were divided into Pre-pandemic (March/2019-February/2020) vs. Pandemic (March/2020-February/2021). The primary outcome was the rate of first liver-related event (LRE). Overall clinical outcomes (LREs plus cardiovascular plus all-cause mortality) were also assessed. Results: A total of 354 patients were included, all of whom were compensated at the beginning of the study period; 83 individuals (23.5%) had a history of prior hepatic decompensation. Mean age was 67.3 years and 48.3% were female. Median BMI was 31.2 kg/m2 and type 2 diabetes was present in 72.8% of patients. The rates of first LRE in the Pre-pandemic and Pandemic periods were 7.4% and 11.3% (p = 0.12), respectively. Whilst the rate of overall events was significantly higher in the Pandemic period (9.9% vs. 17.8%; p = 0.009), this was strongly associated with COVID-19-related deaths. The rate of worsened metabolic status was significantly higher in the Pandemic period (38.4% vs. 46.1%; p = 0.041), yet this was not associated with the risk of first LRE during the Pandemic period, whereas type 2 diabetes (odds ratio [OR] 3.77; 95% CI 1.15-12.32; p = 0.028), albumin <4 g/L (OR 4.43; 95% CI 1.76-11.17; p = 0.002) and Fibrosis-4 score >2.67 (OR 15.74; 95% CI 2.01-123.22; p = 0.009) were identified as risk factors in the multivariable analysis. Conclusion: Overall, people with NAFLD cirrhosis did not present poorer liver-related outcomes during the first year of the pandemic. Health system preparedness seems key to ensure that people with NAFLD cirrhosis receive appropriate care during health crises. Lay summary: Mobility restrictions and social stress induced by the COVID-19 pandemic have led to increased alcohol drinking and worsened metabolic control (e.g., weight gain, poor control of diabetes) in a large proportion of the population in many countries. We aimed to analyze whether people with cirrhosis due to non-alcoholic fatty liver disease, who are particularly vulnerable to such lifestyle modifications, were significantly impacted during the first year of the pandemic. We compared the clinical situation of 354 patients one year before the pandemic and one year after. We found that although metabolic control was indeed worse after the first year of the pandemic and patients presented worse clinical outcomes, the latter was mostly due to non-liver causes, namely COVID-19 itself. Moreover, the care provided to these patients did not worsen during the first year of the pandemic.

High frequency of acute decompensation and cancer in patients with compensated cirrhosis due to nonalcoholic fatty liver disease: A retrospective cohort study.

The natural history of compensated cirrhosis due to nonalcoholic fatty liver disease (NAFLD) has not been completely characterized. The aim of the present study was to assess the incidence and risk factors of acute decompensation of cirrhosis, hepatocellular carcinoma, and extrahepatic cancers. This was a multicenter, retrospective, cohort study including 449 patients with compensated cirrhosis due to NAFLD. We calculated cumulative incidences and used competitive risk analysis to determine the risk factors associated with decompensation and cancer development. Over a median of 39 months of follow-up, 124 patients (28%) presented acute decompensation. The most frequent decompensation was ascites (21%) followed by hepatic encephalopathy (15%), variceal bleeding (9%), and spontaneous bacterial peritonitis (3%). Acute-on-chronic liver failure was diagnosed in 6% of patients during follow-up. Liver function parameters and specifically an albumin level below 40 g/L were independently associated with an increased risk of decompensation. The presence of ischemic heart disease was independently associated with acute decompensation. Seventy-eight patients (18%) developed hepatocellular carcinoma or extrahepatic cancers during follow-up (51 and 27, respectively). Conclusion: Patients with compensated cirrhosis due to NAFLD are at high risk of severe liver complications, such as the development of acute decompensation, in a relative short follow-up time. This population is at high risk of hepatic and extrahepatic cancers.