Mannose-binding lectin deficiency confers risk for bacterial infections in a large Hungarian cohort of patients with liver cirrhosis

Case of Vibrio Vulnificus bacteremia in a patient heterozygous for HFE p.C282Y mutation and alcoholic liver cirrhosis

Vibrio vulnificus is a Gram-negative bacterium, a member of the Vibrionaceae family. V. vulnificus is the main cause of seafood-related deaths in the United States because it can cause severe wound infections or sepsis. This microorganism is highly dependent on iron availability. Therefore, patients with high body iron levels are more susceptible to the infection. Prompt treatment with cephalosporins as well as doxycycline is usually administered. We present a case of V. vulnificus bacteremia in a patient heterozygous for HFE p.C282Y mutation and underlying alcoholic liver cirrhosis.

Liver cirrhosis and immune dysfunction

Cirrhosis is end-stage liver disease resulting from various etiologies and is a common cause of death worldwide. The progression from compensated to decompensated cirrhosis to acute-on-chronic liver failure (ACLF) is due to multiple factors, including continuation of alcohol use or continued exposure to other toxins, an imbalance of the gut microbiota (dysbiosis), increased gut permeability and a disrupted immune response. This disrupted immune response is also named cirrhosis-associated immune dysfunction, which is characterized by worsening systemic inflammation with concomitant immune paralysis, as liver disease deteriorates. This review highlights central immunologic events during the exacerbation of cirrhosis and characterizes the different immune cell populations involved therein.

Cirrhosis-associated immune dysfunction

The term cirrhosis-associated immune dysfunction (CAID) comprises the distinctive spectrum of immune alterations associated with the course of end-stage liver disease. Systemic inflammation and immune deficiency are the key components of CAID. Their severity is highly dynamic and progressive, paralleling cirrhosis stage. CAID involves two different immune phenotypes: the low-grade systemic inflammatory phenotype and the high-grade systemic inflammatory phenotype. The low-grade systemic inflammatory phenotype can be found in patients with compensated disease or clinical decompensation with no organ failure. In this phenotype, there is an exaggerated immune activation but the effector response is not markedly compromised. The high-grade systemic inflammatory phenotype is present in patients with acute-on-chronic liver failure, a clinical situation characterized by decompensation, organ failure and high short-term mortality. Along with high-grade inflammation, this CAID phenotype includes intense immune paralysis that critically increases the risk of infections and worsens prognosis. The intensity of CAID has important consequences on cirrhosis progression and correlates with the severity of liver insufficiency, bacterial translocation and organ failure. Therapies targeting the modulation of the dysfunctional immune response are currently being evaluated in preclinical and clinical studies.

Predictive and Prognostic Value of Ascitic Fluid Mannose Binding Lectin in Patients with Spontaneous Bacterial Peritonitis

BACKGROUND

Spontaneous bacterial peritonitis is a common bacterial infection of ascitic fluid, mainly in ascites due to liver cirrhosis. Mannose-binding lectin (MBL) can activate phagocytosis and the complement system. Spontaneous bacterial peritonitis was detected to be higher in MBL deficiency. This study aimed to assess ascitic fluid MBL in liver cirrhosis and spontaneous bacterial peritonitis.

METHODS

Ninety patients with cirrhotic ascites were included. Forty five of them had SBP. Child- Pugh score, Model for End Stage Liver Disease (MELD) and its update (uMELD) scores were used to assess the severity of liver cirrhosis. Ascitic fluid samples were obtained for differentiation of leucocytic count, estimation of albumin, protein, glucose, and serum-ascitic albumin gradient. Ascitic fluid levels of MBL were measured for all patients. SBP was documented if polymorphonuclear leucocytic count ≥250/mm in ascitic fluid.

RESULTS

Ascitic fluid MBL level was significantly lower in patients with SBP. MBL had a significant negative correlation with ascitic total leukocytic count (TLC), also with serum creatinine, bilirubin, PT, INR and MELD score among SBP patients. However, it had a significant positive correlation with ascitic protein and with platelets. According to multivariate analysis, fever, TLC, platelets, creatinine, MBL, glucose and polymorphs were independent predictors for SBP development.

CONCLUSION

Ascitic fluid MBL could be a good predictive and prognostic marker in patients with cirrhosis and spontaneous bacterial peritonitis.

Association between serum ficolin-1 level and disease progression in primary biliary cholangitis

Pattern recognition molecules (PRMs) in the complement system contribute to homeostasis as mediators of complement activation. The contribution of PRMs to primary biliary cholangitis (PBC) is unknown. In the current study, we aimed to assess the association between PRMs and the clinical findings of PBC. A total of 122 PBC patients and 20 healthy controls were enrolled. We measured four different PRMs (mannose-binding lectin [MBL], ficolin-1, ficolin-2 and ficolin-3) using stored sera, and retrospectively analyzed the associations between PRMs and laboratory findings, histological findings, and the development of cirrhosis-related conditions. Ficolin-1 levels were significantly higher in the PBC patients than in the healthy controls (152 ng/mL vs 102 ng/mL, P = 0.034), but no significant differences were observed regarding MBL, ficolin-2, and ficolin-3 levels. Ficolin-1 was significantly correlated with alkaline phosphatase (ALP). Low ficolin-1 levels were significantly associated with the development of cirrhosis-related conditions independent for histological stage and ALP levels (hazard ratio: 0.933; 95% confidence interval: 0.875-0.994; P = 0.032). Patients with low levels of ficolin-1 (< 77 ng/mL) had a significantly increased rate of developing cirrhosis-related conditions. Low ficolin-1 levels were associated with disease progression independent of histological stage and ALP levels in patients with PBC.

Genetic variants of innate immunity receptors are associated with mortality in cirrhotic patients with bacterial infection

BACKGROUND & AIMS

Acute-on-chronic liver failure (ACLF) is characterized by acute decompensation of cirrhosis (AD), organ failure(s) and high risk of short-term mortality with bacterial infection frequently as precipitating event. Innate immune pattern recognition receptors and members of the lectin pathway of complement activation are crucial to the innate immune response to pathogens. The aim of this study was to investigate whether single nucleotide polymorphisms (SNPs) of innate immune components are associated with the occurrence of bacterial infections or mortality in patients with cirrhosis hospitalized for AD or ACLF.

METHODS

Twenty-one innate immunity SNPs with known functional implications were genotyped in 826 AD/ACLF patients included in the CANONIC study. Associations between baseline characteristics of the patients, the occurrence of bacterial infections and survival rate at 90 days of follow-up in relation to the innate immunity genetic variants were analysed.

RESULTS

The NOD2-G908R genetic variant was associated with mortality (HR 2.25, P = .004) independently of age and MELD Score. This association was also found in a predefined subgroup analysis in patients with bacterial infections (HR 2.78, P < .001) along with MBL_Yx (HR 1.72, P = .008) and MASP2_371 (HR 1.67, P = .012) genetic variants. None of the analysed SNPs were significantly associated with the occurrence of acute bacterial infections or spontaneous bacterial peritonitis in particular.

CONCLUSIONS

Innate immune system-specific NOD2-G908R, MBL_Yx and MASP2_371 genetic variants were independently associated with increased risk of short-term mortality in AD/ACLF patients with bacterial infection.

Immunotherapy in hepatocellular carcinoma: the complex interface between inflammation, fibrosis, and the immune response

Hepatocellular carcinoma (HCC) is the third leading cause of cancer deaths worldwide and confers a poor prognosis. Beyond standard systemic therapy with multikinase inhibitors, recent studies demonstrate the potential for robust and durable responses from immune checkpoint inhibition in subsets of HCC patients across disease etiologies. The majority of HCC arises in the context of chronic inflammation and from within a fibrotic liver, with many cases associated with hepatitis virus infections, toxins, and fatty liver disease. Many patients also have concomitant cirrhosis which is associated with both local and systemic immune deficiency. Furthermore, the liver is an immunologic organ in itself, which may enhance or suppress the immune response to cancer arising within it. Here, we explore the immunobiology of the liver from its native state to chronic inflammation, fibrosis, cirrhosis and then to cancer, and summarize how this unique microenvironment may affect the response to immunotherapy.

Identification of genomic regions and candidate genes of functional importance for gastrointestinal parasite resistance traits in Djallonké sheep of Burkina Faso

A total of 184 Djallonké lambs from Burkina Faso with phenotypes for packed-cell volume (PCV), log-transformed fecal egg count (lnFEC), and FAffa MAlan CHArt (FAMACHA©) eye scores were typed with the OvineSNP50 BeadChip of Illumina to contribute to the knowledge of the genetic basis of gastrointestinal (GIN) parasite resistance in sheep. Association analysis identified a total of 22 single-nucleotide polymorphisms (SNPs) related with PCV (6 SNPs), lnFEC (7), and FAMACHA scores (9) distributed among 14 Ovis aries chromosomes (OAR). The identified SNPs accounted for 18.76 % of the phenotypic variance for PCV, 21.24 % for lnFEC, and 34.38 % for FAMACHA scores. Analyses pointed out the importance of OAR2 for PCV, OAR3 for FAMACHA scores, and OAR6 for lnFEC. The 125 kb regions surrounding the identified SNPs overlapped with seven previously reported quantitative trait loci (QTLs) for the traits analyzed in the current work. The only chromosome harboring markers associated with the three traits studied was OAR2. In agreement with the literature, two different chromosomal areas on OAR2 can play a major role in the traits studied. Gene-annotation enrichment analysis allowed us to identify a total of 34 potential candidate genes for PCV (6 genes), lnFEC (4), and FAMACHA scores (24). Annotation analysis allowed us to identify one functional term cluster with a significant enrichment score (1.302). The cluster included five genes (TRIB3, CDK4, CSNK2A1, MARK1, and SPATA5) involved in immunity-related and cell-proliferation processes. Furthermore, this research suggests that the MBL2 gene can underlie a previously reported QTL for immunoglobulin A levels on OAR22 and confirms the importance of genes involved in growth and size (such as the ADAMTS17 gene on OAR18) for GIN resistance traits. Since association studies for the ascertainment of the genetic basis of GIN resistance may be affected by genotype-environment interactions, obtaining information from local sheep populations managed in harsh environments contributes to the identification of novel genomic areas of functional importance for GIN resistance for that trait.

Causes and Consequences of Innate Immune Dysfunction in Cirrhosis

Liver cirrhosis is an increasing health burden and public health concern. Regardless of etiology, patients with cirrhosis are at risk of a range of life-threatening complications, including the development of infections, which are associated with high morbidity and mortality and frequent hospital admissions. The term Cirrhosis-Associated Immune Dysfunction (CAID) refers to a dynamic spectrum of immunological perturbations that develop in patients with cirrhosis, which are intimately linked to the underlying liver disease, and negatively correlated with prognosis. At the two extremes of the CAID spectrum are systemic inflammation, which can exacerbate clinical manifestations of cirrhosis such as hemodynamic derangement and kidney injury; and immunodeficiency, which contributes to the high rate of infection in patients with decompensated cirrhosis. Innate immune cells, in particular monocytes/macrophages and neutrophils, are pivotal effector and target cells in CAID. This review focuses on the pathophysiological mechanisms leading to impaired innate immune function in cirrhosis. Knowledge of the phenotypic manifestation and pathophysiological mechanisms of cirrhosis associated immunosuppression may lead to immune targeted therapies to reduce susceptibility to infection in patients with cirrhosis, and better biomarkers for risk stratification, and assessment of efficacy of novel immunotherapies.

Prognostic value of lectin pathway molecules and complement proteins in ascitic fluid and blood in patients with liver cirrhosis

BACKGROUND AND AIM

Patients with liver cirrhosis and ascites have a poor prognosis with increased risk of infection related death, as advanced stages of cirrhosis are associated with immunodeficiency. We aimed to investigate immunologically active molecules in ascitic fluid and blood and their potential association to survival.

MATERIALS AND METHODS

In an exploratory pilot study; blood and ascitic fluid from 34 patients with liver cirrhosis of different etiology were analyzed for pattern recognition molecules (ficolin-1, ficolin-2, ficolin-3 and MBL) and complement proteins (C4 and C3). An observational follow-up study (minimum 17 months) was conducted to assess the association to all-cause mortality or liver transplantation.

RESULTS

Ficolin-1, ficolin-2, MBL, C4 and C3 in ascitic fluid and ficolin-1, C4 and C3 in blood were significantly (p = .001-.027) lower in patients with Child-Pugh stage C (n = 16, 47%) compared to Child-Pugh stage B cirrhosis (n = 18, 53%). In multivariate COX-regression analysis low levels of ficolin-1(p = .036) and C3 (p = .025) in ascitic fluid and C4(p = .005) and C3 (p = .032) in serum were associated with all-cause mortality or liver transplantation independent of Child-Pugh score.

CONCLUSION

Levels of lectin-complement pathway molecules in ascitic fluid and blood are lower in patients with more advanced stage of cirrhosis. Low C4 and C3 in serum and C3 and ficolin-1 in ascitic fluid are risk factors for all-cause mortality or liver transplantation independently of liver function in patients with cirrhosis and ascites.

Lectin-complement pathway molecules are decreased in patients with cirrhosis and constitute the risk of bacterial infections

BACKGROUND & AIMS

Lectin pathway molecules of the complement system are synthesized by hepatocytes and have pivotal role in innate host defence against infectious organisms. Ficolins (FCNs) act as soluble pattern recognition molecules, while mannan-binding lectin serine proteases(MASPs) do as effector molecules in elimination of pathogens. We aimed to study the significance of low level of these molecules in the development of cirrhosis-associated bacterial infections, which has not been elucidated so far.

METHODS

Sera of 266 stable outpatients with cirrhosis and 160 healthy subjects were assayed for a panel of lectin molecules (FCN-2, FCN-3 and MASP-2) by ELISA. In cirrhosis, a 5-year follow-up observational study was conducted to assess a possible association between lectin levels and development of clinically significant bacterial infections(CSI).

RESULTS

FCN-2, FCN-3 and MASP-2 levels were significantly lower in cirrhosis compared to healthy subjects and decreased according to disease severity (P<.001 for all molecules). In Kaplan-Meier analysis, development of CSI was associated with low level of FCN-2 (<427 ng/mL, pLogRank=0.047) and FCN-3 (<4857 ng/mL, pLogRank=0.029), but not with MASP-2 deficiency (<100 ng/mL, pLogRank=0.306). Combined FCN deficiency was associated with increased risk of development of bacterial infections in a step-wise manner. Patients with low level of both FCNs had higher cumulative probability of CSI (63.8%) compared to those with low level of one or normal FCN (52.7% and 45.7%, pLogRank=0.016). Neither FCN serum profile, nor MASP-2 deficiency were associated with infection-related mortality.

CONCLUSIONS

Low level of FCNs associated with hepatic insufficiency might be considered as an additional constituent of cirrhosis-associated immune dysfunction.

Evaluation of Mannose-Binding Lectin is a Useful Approach to Predict the Risk of Infectious Complications Following Autologous Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) associated immunocompromised state carries high risk of infectious complications. Mannose-binding lectin (MBL) is an acute phase protein involved in innate immune response. Serum MBL level is genetically determined and quite stable. According to literature, significant association was shown between low MBL concentrations and serious infections. The association between serum MBL level and frequency and severity of infections was studied in 186 patients following autologous HSCT. Double-monoclonal antibody sandwich enzyme-linked immunosorbent assay was used to determine MBL antigen level in sera. MBL levels were measured around 100 days following transplantation, in a period without active infection. Twenty-one patients (11%) were MBL deficient. The median time of first infection and number of infections during the first year post-transplantation were not significantly different between patients with MBL deficiency and those without MBL deficiency. The occurrence and number of infections after HSCT correlated with the MBL/C-reactive protein ratio. The number of severe infections was not higher among those with MBL deficiency. The occurrence of infections after the pre-engraftment period during the first year post-transplantation was significantly different in patient groups separated by MBL cut-off level. The MBL/C-reactive protein ratio might be a useful marker of infectious complications. MBL measurement may be helpful in antibiotic treatment. In case of MBL deficiency, earlier and more intensive treatment may be indicated.

Immune Dysfunction in Cirrhosis

Cirrhosis due to any etiology disrupts the homeostatic role of liver in the body. Cirrhosis-associated immune dysfunction leads to alterations in both innate and acquired immunity, due to defects in the local immunity of liver as well as in systemic immunity. Cirrhosis-associated immune dysfunction is a dynamic phenomenon, comprised of both increased systemic inflammation and immunodeficiency, and is responsible for 30% mortality. It also plays an important role in acute as well as chronic decompensation. Immune paralysis can accompany it, which is characterized by increase in anti-inflammatory cytokines and suppression of proinflammatory cytokines. There is also presence of increased gut permeability, reduced gut motility and altered gut flora, all of which leads to increased bacterial translocation. This increased bacterial translocation and consequent endotoxemia leads to increased blood stream bacterial infections that cause systemic inflammatory response syndrome, sepsis, multiorgan failure and death. The gut microbiota of cirrhotic patients has more pathogenic microbes than that of non-cirrhotic individuals, and this disturbs the homeostasis and favors gut translocation. Prompt diagnosis and treatment of such infections are necessary for better survival. We have reviewed the various mechanisms of immune dysfunction and its consequences in cirrhosis. Recognizing the exact pathophysiology of immune dysfunction will help treating clinicians in avoiding its complications in their patients and can lead to newer therapeutic interventions and reducing the morbidity and mortality rates.

Mechanisms of susceptibility to bacterial infections in cirrhotic patients

Bacterial infections are very common in cirrhotic patients, and the incidence is 4-5 times higher than that in the general population. The mechanisms of susceptibility to bacterial infections in cirrhotic patients include intestinal bacterial overgrowth, bacterial translocation, increased number of potentially pathogenic bacteria accompanied by reduced number of beneficial bacteria; small bowel motility disturbances and delayed gut transit, increased intestinal permeability; genetic predisposition to bacterial infections; immunodeficiency accompanied by persistent activation of the immune cells with production of pro-inflammatory cytokines. In this paper, we will discuss the mechanisms of susceptibility to bacterial infections in cirrhotic patients.

Cirrhosis-associated immune dysfunction: distinctive features and clinical relevance

The term cirrhosis-associated immune dysfunction refers to the main syndromic abnormalities of immune function, immunodeficiency and systemic inflammation that are present in cirrhosis. The course of advanced cirrhosis, regardless of its aetiology, is complicated by cirrhosis-associated immune dysfunction and this constitutes the pathophysiological hallmark of an increased susceptibility to bacterial infection, distinctive of the disease. Cirrhosis impairs the homeostatic role of the liver in the systemic immune response. Damage to the reticulo-endothelial system compromises the immune surveillance function of the organ and the reduced hepatic synthesis of proteins, involved in innate immunity and pattern recognition, hinders the bactericidal ability of phagocytic cells. Systemic inflammation, in form of activated circulating immune cells and increased serum levels of pro-inflammatory cytokines, is the result of persistent episodic activation of circulating immune cells from damage-associated molecular patterns, released from necrotic liver cells and, as cirrhosis progresses, from pathogen-associated molecular patterns, released from the leaky gut. Cirrhosis-associated immune dysfunction phenotypes switch from predominantly "pro-inflammatory" to predominantly "immunodeficient" in patients with stable ascitic cirrhosis and in patients with severely decompensated cirrhosis and extra-hepatic organ failure (e.g. acute-on-chronic liver failure), respectively. These cirrhosis-associated immune dysfunction phenotypes represent the extremes of a spectrum of reversible dynamic events that take place during the course of cirrhosis. Systemic inflammation can affect the functions of tissue somatic cells and modify the clinical manifestation of cirrhosis. The best characterized example is the contribution of systemic inflammation to the haemodynamic derangement of cirrhosis, which correlates negatively with prognosis.

Potential role of the lectin pathway of complement in the pathogenesis and disease manifestations of systemic sclerosis: a case-control and cohort study

Introduction

Repetitive episodes of ischemia and reperfusion (I/R) are a cardinal feature of the pathogenesis of systemic sclerosis (SSc), which precedes tissue fibrosis. The complement system is a key mediator of tissue damage after I/R, primarily by activation of the lectin pathway. This study investigated whether serum levels and polymorphisms of mannose-binding lectin (MBL) and ficolin-2 (FCN2), two pattern recognition receptors of the lectin pathway, are associated with the predisposition to and clinical features of SSc.

Methods

A case-control study was undertaken involving 90 patients with SSc from a single SSc outpatient clinic and 90 age- and sex-matched blood donors. MBL and FCN2 levels and polymorphisms were measured in both groups, and in cases correlated with clinical data.

Results

MBL levels and genotypes were equally distributed in cases and controls while there were some significant differences in FCN2 polymorphisms. Median MBL levels were higher in SSc cases with diffuse disease compared with controls (2.6 versus 1.0 μg/ml, P <0.001).

In cases, higher MBL levels were associated with the presence of clinical findings associated with vascular dysfunction and local tissue damage (digital ulcers, calcinosis and pitting). Moreover, MBL levels were associated with fibrotic disease manifestations as evidenced by the presence of diffuse disease (median 2.6 versus 0.8 μg/ml, P = 0.002), the modified Rodnan skin score (r = 0.39, P <0.001), and interstitial lung disease as measured by forced vital capacity (r = −0.33, P = 0.001). Importantly, MBL levels also correlated with the Scleroderma Health Assessment Questionnaire scores (r = 0.33, P = 0.002). The results for FCN2 levels were less striking. Phenotypic MBL results were largely confirmed by analysis of MBL polymorphisms. MBL levels were not associated with the presence of autoantibodies or hypocomplementaemia.

Conclusions

Overall, predisposition to SSc was not influenced by the lectin pathway of complement in our matched case-control study. However, our preliminary data suggest that MBL, and to a lesser extent FCN2, may modulate disease manifestations of SSc, particularly in diffuse cutaneous disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-014-0480-6) contains supplementary material, which is available to authorized users.

Immune dysfunction in cirrhosis

Innate and adaptive immune dysfunction, also referred to as cirrhosis-associated immune dysfunction syndrome, is a major component of cirrhosis, and plays a pivotal role in the pathogenesis of both the acute and chronic worsening of liver function. During the evolution of the disease, acute decompensation events associated with organ failure(s), so-called acute-on chronic liver failure, and chronic decompensation with progression of liver fibrosis and also development of disease specific complications, comprise distinct clinical entities with different immunopathology mechanisms. Enhanced bacterial translocation associated with systemic endotoxemia and increased occurrence of systemic bacterial infections have substantial impacts on both clinical situations. Acute and chronic exposure to bacteria and/or their products, however, can result in variable clinical consequences. The immune status of patients is not constant during the illness; consequently, alterations of the balance between pro- and anti-inflammatory processes result in very different dynamic courses. In this review we give a detailed overview of acquired immune dysfunction and its consequences for cirrhosis. We demonstrate the substantial influence of inherited innate immune dysfunction on acute and chronic inflammatory processes in cirrhosis caused by the pre-existing acquired immune dysfunction with limited compensatory mechanisms. Moreover, we highlight the current facts and future perspectives of how the assessment of immune dysfunction can assist clinicians in everyday practical decision-making when establishing treatment and care strategies for the patients with end-stage liver disease. Early and efficient recognition of inappropriate performance of the immune system is essential for overcoming complications, delaying progression and reducing mortality.

Management of bacterial infections in cirrhosis

Bacterial infections are very frequent in advanced cirrhosis and become the first cause of death of these patients. Despite numerous experimental data and significant advances in the understanding of the pathogenesis of sepsis in cirrhosis, the outcome remains poor. Classical diagnostic parameters such as C-reactive protein and SIRS criteria have less diagnostic capacity in the cirrhotic population, often delaying the diagnosis and the management of bacterial infection. Prompt and appropriate empirical antibiotic treatment of infection and early resuscitation of patients with severe sepsis or septic shock are essential in determining patient's outcome. A strategy of careful restriction of prophylactic antibiotics to the high-risk populations could reduce the spread of multidrug resistant bacteria. This review is focused on the currently recommended diagnostic, therapeutic and prophylactic strategies for bacterial infections in the cirrhotic population.

Acute phase proteins in the diagnosis and prediction of cirrhosis associated bacterial infections

BACKGROUND

Bacterial infections are common cause of morbidity and mortality in patients with cirrhosis. The early diagnosis of these infections is rather difficult.

AIMS

To assess the accuracy of acute phase proteins in the identification of bacterial infections.

METHODS

Concentration of C-reactive protein (CRP), procalcitonin (PCT), lipopolysaccharide-binding protein (LBP), sCD14 and antimicrobial antibodies were measured in serum of 368 well-characterized patients with cirrhosis of whom 139 had documented infection. Clinical data was gathered by reviewing the patients' medical charts.

RESULTS

Serum levels of CRP, PCT and LBP were significantly higher in patients with clinically overt infections. Among the markers, CRP - using a 10 mg/L cut-off value- proved to be the most accurate in identifying patients with infection (AUC: 0.93). The accuracy of CRP, however, decreased in advanced stage of the disease, most probably because of the significantly elevated CRP levels in non-infected patients. Combination of CRP and PCT increased the sensitivity and negative predictive value, compared with CRP on its own, by 10 and 5% respectively. During a 3-month follow-up period in patients without overt infections, Kaplan-Meier and proportional Cox-regression analyses showed that a CRP value of >10 mg/L (P = 0.035) was independently associated with a shorter duration to progress to clinically significant bacterial infections. There was no correlation between acute phase protein levels and antimicrobial seroreactivity.

CONCLUSIONS

C-reactive protein on its own is a sensitive screening test for the presence of bacterial infections in cirrhosis and is also a useful marker to predict the likelihood of clinically significant bacterial infections in patients without overt infections.

Systemic inflammatory response syndrome in patients with liver cirrhosis

BACKGROUND AND STUDY AIMS

Patients with liver cirrhosis present an increased susceptibility to the systemic inflammatory response syndrome (SIRS), which is considered the cause of hospital admission in about 10% of patients and is present in about 40% of those admitted for ongoing complications. We tried to assess the prevalence of the SIRS with the possible effects on the course of the disease during hospital stay.

PATIENTS AND METHODS

Two hundred and three patients with liver cirrhosis were examined and investigated with close monitoring during hospital stay. The main clinical endpoints were death and the development of portal hypertension-related complications.

RESULTS

Eighty-one patients met the criteria of SIRS (39.9%). We found significant correlations between SIRS and jaundice (p=0.005), bacterial infection (p=0.008), white blood cell count (p<0.001), low haemoglobin concentration (p=0.004), high serum creatinine levels (p<0.001), high alanine aminotransferase levels (p<0.001), serum bilirubin levels (p<0.001), international normalised ratio (p<0.001), serum albumin levels (p=0.033), high Child-Pugh score (p<0.001). During the follow-up period, 26 patients died (12.8%), 15 developed portal hypertension-related bleeding (7.3%), 30 developed hepatic encephalopathy (14.7%), and 9 developed hepatorenal syndrome type-1 (4.4%). SIRS showed significant correlations both to death (p<0.001) and to portal hypertension-related complications (p<0.001).

CONCLUSION

The systemic inflammatory response syndrome occurs in patients with advanced cirrhosis and is associated with a bad prognosis.

Presence of anti-microbial antibodies in liver cirrhosis--a tell-tale sign of compromised immunity?

Background

Bacterial translocation plays important role in the complications of liver cirrhosis. Antibody formation against various microbial antigens is common in Crohn's disease and considered to be caused by sustained exposure to gut microflora constituents. We hypothesized that anti-microbial antibodies are present in patients with liver cirrhosis and may be associated with the development of bacterial infections.

Methodology/Principal Findings

Sera of 676 patients with various chronic liver diseases (autoimmune diseases:266, viral hepatitis C:124, and liver cirrhosis of different etiology:286) and 100 controls were assayed for antibodies to Saccharomyces cerevisiae(ASCA) and to antigens derived from two intestinal bacterial isolates (one gram positive, one gram negative, neither is Escherichia coli). In patients with liver cirrhosis, we also prospectively recorded the development of severe episodes of bacterial infection. ASCA and anti-OMP Plus™ antibodies were present in 38.5% and 62.6% of patients with cirrhosis and in 16% and 20% of controls, respectively (p<0.001). Occurrence of these antibodies was more frequent in cases of advanced cirrhosis (according to Child-Pugh and MELD score; p<0.001) or in the presence of ascites (p<0.001). During the median follow-up of 425 days, 81 patients (28.3%) presented with severe bacterial infections. Anti-microbial antibody titers (p = 0.003), as well as multiple seroreactivity (p = 0.036), was associated with infectious events. In logistic regression analysis, the presence of ascites (OR:1.62, 95%CI:1.16–2.25), co-morbidities (OR:2.22, 95%CI:1.27–3.86), and ASCA positivity (OR:1.59, 95%CI:1.07–2.36) were independent risk factors for severe infections. A shorter time period until the first infection was associated with the presence of ASCA (p = 0.03) and multiple seropositivity (p = 0.037) by Kaplan-Meier analysis, and with Child-Pugh stage (p = 0.018, OR:1.85) and co-morbidities (p<0.001, OR:2.02) by Cox-regression analysis.

Conclusions/Significance

The present study suggests that systemic reactivity to microbial components reflects compromised mucosal immunity in patients with liver cirrhosis, further supporting the possible role of bacterial translocation in the formation of anti-microbial antibodies.