R.D. Abeles

Infection and systemic inflammation, not ammonia, are associated with Grade 3/4 hepatic encephalopathy, but not mortality in cirrhosis

BACKGROUND & AIMS Patients with cirrhosis are prone to infection which is a frequent precipitant of hepatic encephalopathy (HE). Clinical studies have examined the importance of inflammation and infection in modulating the manifestation of symptoms of HE in acute liver failure and patients with cirrhosis and minimal/low grade HE. It would be logical to presume that this relationship persists in patients who develop severe HE in cirrhosis although this has not been examined to date. METHODS We report the findings of a prospective audit of 100 consecutive patients with cirrhosis admitted between Jan 2000 and March 2008 to a liver Intensive Care Unit (ICU) where HE was the primary indication for admission (59% Grade 3; 41% Grade 4). Haematological and microbiological data were collected at ICU admission, and organ scores and outcomes were recorded. RESULTS 46% of patients had positive cultures taken within ± 48h from admission to ICU [25% blood] and a further 22% were culture negative but had evidence of systemic inflammation (SIRS). SIRS score (p=0.03) and SOFA score (p=0.006) were significantly higher in those patients with Grade 4 HE, who were also less likely to survive (p<0.001). HE grade/coma score did not correlate with ammonia, biochemistry or MELD score. Fifty-two percent of patients survived their ICU stay while the remainder developed progressive multiorgan failure and died; 38% survived to discharge, and 16% were transplanted. CONCLUSIONS These data support an association between infection/SIRS and not ammonia, in patients with cirrhosis that develop severe HE. The presence or absence of infection/SIRS did not determine survival.

Source and characterization of hepatic macrophages in acetaminophen‐induced acute liver failure in humans

Acetaminophen‐induced acute liver failure (AALF) is associated with innate immunity activation, which contributes to the severity of hepatic injury and clinical outcome. A marked increase in hepatic macrophages (h‐mϕ) is observed in experimental models of AALF, but controversy exists regarding their role, implicating h‐mϕ in both aggravation and resolution of liver injury. The role of h‐mϕ in human AALF is virtually unexplored. We sought to investigate the role of chemokine (C‐C motif) ligand 2 (CCL2) in the recruitment of circulating monocytes to the inflamed liver and to determine how the h‐mϕ infiltrate and liver microenvironment may contribute to tissue repair versus inflammation in AALF. We evaluated circulating monocytes, their chemokine (C‐C motif) receptor 2 (CCR2) expression, and serum CCL2 levels in patients with AALF. Cell subsets and numbers of circulation‐derived (MAC387+) or resident proliferating (CD68/Ki67+) h‐mϕ in hepatic immune infiltrates were determined by immunohistochemistry. Inflammatory cytokine levels were determined in whole and laser microdissected liver tissue by proteome array. In AALF, circulating monocytes were depleted, with the lowest levels observed in patients with adverse outcomes. CCL2 levels were high in AALF serum and hepatic tissue, and circulating monocyte subsets expressed CCR2, suggesting CCL2‐dependent hepatic monocyte recruitment. Significant numbers of both MAC387+ and CD68+ h‐mϕ were found in AALF compared with control liver tissue with a high proportion expressing the proliferation marker Ki67. Levels of CCL2, CCL3, interleukin (IL)‐6, IL‐10, and transforming growth factor‐β1 were significantly elevated in AALF liver tissue relative to chronic liver disease controls. Conclusion: In AALF, the h‐mϕ population is expanded in areas of necrosis, both through proliferation of resident cells and CCL2‐dependent recruitment of circulating monocytes. The presence of h‐mϕ within an anti‐inflammatory/regenerative microenvironment indicates that they are implicated in resolution of inflammation/tissue repair processes during AALF. (HEPATOLOGY 2012)

CD14, CD16 and HLA-DR reliably identifies human monocytes and their subsets in the context of pathologically reduced HLA-DR expression by CD14(hi) /CD16(neg) monocytes: Expansion of CD14(hi) /CD16(pos) and contraction of CD14(lo) /CD16(pos) monocytes in acute liver failure

Changes in monocytes and their subsets (CD14hi/CD16neg, CD14hi/CD16pos and CD14lo/CD16pos) have been described in several diseases. The combination of CD14, CD16 and HLA‐DR has been suggested to discriminate monocytes from the CD16pos/HLA‐DRneg NK‐cells and neutrophils but no data exist whether this strategy can be used in situations when monocyte HLA‐DR expression is pathologically reduced. Monocytes and their subsets were concurrently identified through negative (exclusion of CD66bpos neutrophils, CD56pos NKcells, CD19pos B‐cells, and CD3pos T‐cells) and positive gating (inclusion of monocytes by expression of CD14, CD16, and HLA‐DR) strategies on 30 occasions [9 healthy controls (HC) and 21 patients with conditions associated with low monocyte HLA‐DR expression]. Bland‐Altman and Passing and Bablok regression statistics did not demonstrate any significant measurement bias between the two strategies of monocyte identification. Monocyte subset phenotype was then compared in 18 HC and 41 patients with acute liver failure (ALF). Compared with HC, in ALF, the percentage of CD14hi/CD16pos monocytes was higher (7% vs 4%) whilst the percentage of CD14lo/CD16pos was lower (1.9% vs. 7%) (P ≤ 0.001); HLA‐DR and CD86 MFIs on all monocyte subsets were lower, whilst CCR5, CD64, and CD11b MFIs were higher (P < 0.05). The relative expression by monocyte subsets of HLA‐DR, CCR2, CCR5, CX3CR1, and CD11a was similar in ALF patients and HCs. Repeat analysis of an identical antibody‐fluorochrome “backbone” targeting HLA‐DR, CD14, and CD16 was assessed in 189 samples across 5 different experiments. There was excellent agreement in the results obtained using the positive gating strategy (interclass correlation coefficients > 0.8). Monocytes and their subsets can be reliably identified using an antibody‐fluorochrome “backbone” of HLA‐DR, CD14, and CD16. CD16pos monocytes continue to constitutively express HLA‐DR even in conditions where HLA‐DR is pathologically reduced on CD14hi/CD16neg monocytes. Understanding the changes in monocyte pheontype in ALF and similar clinico‐pathological diseases may allow the development of novel biomarkers or therapeutic strategies.

The impact of organ dysfunction in cirrhosis: survival at a cost?

BACKGROUND & AIMS The incidence of cirrhosis and subsequent development of organ dysfunction (OD) requiring intensive care unit (ICU) support is rising. Historically, critically ill cirrhotics are perceived as having poor prognosis and substantial cost of care. METHODS The aim was to prospectively analyse resource utilisation and cost of a large cohort of patients (n=660) admitted to a Liver ICU from 2000 to 2007 with cirrhosis and OD. Child Pugh, MELD, SOFA, APACHE II, and organ support requirements were collected. The Therapeutic Intervention Scoring System (TISS) score, a validated tool for estimating cost in ICU, was calculated daily. Logistic regression was used to determine independent predictors of increased cost. RESULTS Alcohol was the most common etiology (47%) and variceal bleeding (VB) the most common reason for admission (35%). Invasive ventilatory support was required in 74% of cases, vasopressors in 49%, and 50% required renal replacement therapy. Forty-nine per cent of non-transplanted patients survived to ICU discharge. Median TISS score and ICU cost per patient were 261 and €14,139, respectively. VB patients had the highest survival rates (53% vs. 24%; p<0.001) and lower associated cost. A combination of VB (OR 0.48), need for ventilation (OR 2.81), low PO(2)/FiO(2) on admission (OR 0.97), and lactate (OR 0.93) improved cost prediction on multivariate analysis (AUROC 0.7; p<0.001) but organ failure scores per se were poor predictors of cost. CONCLUSIONS Patients with cirrhosis and OD result in considerable resource expenditure but have acceptable hospital survival. Further health economic assessment and outcome prediction tools are required to appropriately target resource utilisation.

Secretory leukocyte protease inhibitor: a pivotal mediator of anti-inflammatory responses in acetaminophen-induced acute liver failure.

Acetaminophen‐induced acute liver failure (AALF) is characterized both by activation of innate immune responses and susceptibility to sepsis. Circulating monocytes and hepatic macrophages are central mediators of inflammatory responses and tissue repair processes during human AALF. Secretory leukocyte protease inhibitor (SLPI) modulates monocyte/macrophage function through inhibition of nuclear factor kappa B (NF‐κB) signaling. The aims of this study were to establish the role of SLPI in AALF. Circulating levels of SLPI, monocyte cluster of differentiation 163 (CD163), human leukocyte antigen‐DR (HLA‐DR), and lipopolysaccharide (LPS)‐stimulated levels of NF‐κBp65, tumor necrosis factor alpha (TNF‐α) and interleukin (IL)‐6 were determined in patients with AALF, chronic liver disease, and healthy controls. Immunohistochemistry and multispectral imaging of AALF explant tissue determined the cellular sources of SLPI and hepatic macrophage phenotype. The phenotype and function of monocytes and macrophages was determined following culture with recombinant human (rh)‐SLPI, liver homogenates, and plasma derived from AALF patients in the presence and absence of antihuman (α)SLPI. Hepatic and circulatory concentrations of SLPI were elevated in AALF and immunohistochemistry revealed SLPI expression in biliary epithelial cells and within hepatic macrophages (h‐mψ) in areas of necrosis. H‐mψ and circulating monocytes in AALF exhibited an anti‐inflammatory phenotype and functional characteristics; typified by reductions in NF‐κBp65, TNF‐α, and IL‐6 and preserved IL‐10 secretion following LPS challenge. Culture of healthy monocytes with AALF liver homogenates, plasma, or rhSLPI induced monocytes with strikingly similar anti‐inflammatory characteristics which were reversed by inhibiting the activity of SLPI. Conclusion: SLPI is a pivotal mediator of anti‐inflammatory responses in AALF through modulation of monocyte/macrophage function, which may account for the susceptibility to sepsis in AALF. (Hepatology 2014;59:1564‐1576)

Increased Survival for Patients With Cirrhosis and Organ Failure in Liver Intensive Care and Validation of the Chronic Liver Failure–Sequential Organ Failure Scoring System

BACKGROUND & AIMS During the past decade, survival has increased among patients admitted to general intensive care units, but it is not clear if it has increased for patients admitted with cirrhosis and organ failure. The chronic liver failure-sequential organ failure assessment (CLIF-SOFA) recently was developed as an adaptation to the SOFA to predict outcomes of patients, but requires validation. We investigated changes in outcomes of patients with cirrhosis and organ failure since 2000, compared the abilities of SOFA and CLIF-SOFA to predict patient survival, and validated the CLIF-SOFA system. METHODS In a retrospective study, we collected data from 971 patients (median age, 52 y; age range, 16-90 y; 62% male) with cirrhosis (54% alcohol associated, 12% viral, and 34% other causes). The patients were admitted under emergency conditions from January 1, 2000, to December 31, 2010, to a liver intensive therapy unit in the United Kingdom. Patient survival while in the hospital was compared with measures of illness severity, Acute Physiology and Chronic Health Evaluation (APACHE) II scores, model for end-stage liver disease (MELD) scores, SOFA scores, and CLIF-SOFA scores. RESULTS Patients had a median APACHE II score of 21 (range, 5-50) and a median MELD score of 23 (range, 6-40). The median APACHE II score at admission decreased from 23 to 22 over the study period (P < .001), whereas the median MELD score at admission decreased from 23 to 18 (P < .001). Overall survival until hospital discharge was 51%; this value increased from 40% in 2000 to 63% in 2010 (P < .001). The unadjusted odds ratio for change in mortality/year was 0.87 (95% confidence interval, 0.83-0.91; P < .001). The APACHE II score adjusted odds ratio for mortality was 0.89 (95% confidence interval, 0.84-0.93; P < .001). The etiology of cirrhosis was not associated with a significant difference in survival. CLIF-SOFA and SOFA scores at the time of admission predicted patient survival with area under the receiver operating curve (AUROC) values of 0.813 and 0.799, respectively; the scores at 48 hours after admission predicted survival with AUROC values of 0.853 and 0.840, and scores after 1 week predicted survival with AUROC values of 0.842 and 0.844, respectively. These AUROC values were higher than those obtained from APACHE II or MELD scores. CONCLUSIONS The proportion of patients with cirrhosis who survived after admission to intensive care increased from 2000 to 2010. SOFA and CLIF-SOFA scores during the first week of critical care appear to have similar abilities to predict patient survival.

The severity of circulating neutrophil dysfunction in patients with cirrhosis is associated with 90-day and 1-year mortality

Patients with cirrhosis are susceptible to sepsis, pre‐disposing to the development of encephalopathy, bleeding and organ dysfunction with associated high mortality.

Immunopathogenesis of primary biliary cirrhosis: an old wives' tale

Primary biliary cirrhosis (PBC) is a cholestatic liver disease characterised by the autoimmune destruction of the small intrahepatic bile ducts. The disease has an unpredictable clinical course, but may progress to fibrosis and cirrhosis. Although medical treatment with urseodeoxycholic acid is largely successful, some patients may progress to liver failure requiring liver transplantation. PBC is characterised by the presence of disease specific anti-mitochondrial (AMA) antibodies, which are pathognomonic for PBC development. The disease demonstrates an overwhelming female preponderance and virtually all women with PBC present in middle age. The reasons for this are unknown; however several environmental and immunological factors may be involved. As the immune systems ages, it become less self tolerant, and mounts a weaker response to pathogens, possibly leading to cross reactivity or molecular mimicry. Some individuals display immunological changes which encourage the development of autoimmune disease. Risk factors implicated in PBC include recurrent urinary tract infection in females, as well as an increased prevalence of reproductive complications. These risk factors may work in concert with and possibly even accelerate, immune system ageing, contributing to PBC development. This review will examine the changes that occur in the immune system with ageing, paying particular attention to those changes which contribute to the development of autoimmune disease with increasing age. The review also discusses risk factors which may account for the increased female predominance of PBC, such as recurrent UTI and oestrogens.

Alcohol dehydrogenase–specific T‐cell responses are associated with alcohol consumption in patients with alcohol‐related cirrhosis

Patients with alcohol‐related liver disease (ALD) have antibodies directed to alcohol dehydrogenase (ADH), anti‐ADH titers being associated with disease severity and active alcohol consumption. ADH‐specific T‐cell responses have not been characterized. We aimed to define anti‐ADH cellular immune responses and their association with active alcohol consumption and disease severity. Using cultures of peripheral blood mononuclear cells (PBMCs) from 25 patients with alcohol‐related cirrhosis (ARC; 12 were actively drinking or abstinent for <6 months, and 13 were abstinent for >6 months) and hepatic mononuclear cells (HMCs) from 14 patients with ARC who were undergoing transplantation, we investigated T‐cell reactivity to 25 overlapping peptides representing the full human ADH protein (beta 1 subunit). ADH‐specific peripheral T‐cell responses were assessed by the quantification of T‐cell proliferation and cytokine production and were correlated with the clinical course. In active alcohol consumers, proliferative T‐cell responses targeted ADH31‐95 and other discontinuous sequences in the ADH peptide, whereas only one sequence was targeted in abstinents. ADH peptides induced the production of interferon‐γ (IFN‐γ), interleukin‐4 (IL‐4), and IL‐17. IL‐4 production was lower in active drinkers versus abstinents, and IL‐17 production was higher. Peptides inducing IFN‐γ production outnumbered those inducing T‐cell proliferation. The intensity of the predominantly T helper 1 (Th1) responses directly correlated with disease severity. Similar to PBMCs in abstinents, ADH peptides induced weak T‐cell proliferation and a similar level of IL‐4 production in HMCs but less vigorous Th1 and T helper 17 responses. Conclusion: This suggests that Th1 responses to ADH in ARC are induced by alcohol consumption. A Th1/T helper 2 imbalance characterizes T‐cell responses in active drinkers with ARC, whereas IL‐4 production prevails in abstinents. This identifies new targets for immunoregulatory therapies in ALD patients for halting detrimental effector T‐cell responses, which may encourage liver fibrogenesis and progression to end‐stage liver disease. (HEPATOLOGY 2013)

Multivariate metabotyping of plasma predicts survival in patients with decompensated cirrhosis.

Graphical abstract