Nosocomial spontaneous bacterial peritonitis and bacteremia in cirrhotic patients: impact of isolate type on prognosis and characteristics of infection

Clinical and microbiological characteristics of persistent Staphylococcus aureus bacteremia, risk factors for mortality, and the role of CD4+ T cells

This study evaluated the determinants of mortality and the T cell immune response in patients with persistent Staphylococcus aureus bacteremia (SAB). This was a prospective cohort study and patients with confirmed SAB were enrolled from 2008 to 2020. We compared clinical, microbiological, and genotypic features between surviving and deceased patients with persistent SAB. The concentrations of cytokines and the proportions of IFN-γ secreting CD4+ T cells were measured serially during the bacteremia period. Of the 1760 patients, 242 had persistent bacteremia (PB), and 49 PB patients died within 30 days. In the multivariate analysis, the APACHE II score and female sex were independently associated with 30 days mortality. The level of IL-10 was significantly increased in the plasma of patients with a high Pitt bacteremia score and those who died within 12 weeks from the index day. The proportion of IFN-γ-secreting CD4+ T cells were the highest just before the positive-to-negative conversion of blood cultures in patients with a low Pitt bacteremia score and those who survived for 12 weeks. The level of IL-10 is correlated with clinical outcomes in PB patients. IFN-γ secreting CD4+ T cells might play a pivotal role in SAB PB.

Spontaneous Bacterial Peritonitis in Decompensated Liver Cirrhosis—A Literature Review

Background: Spontaneous bacterial peritonitis (SBP) is defined as a bacterial infection of the ascitic fluid without a surgically treatable intra-abdominal infection source. SBP is a common, severe complication in cirrhosis patients with ascites, and if left untreated, in-hospital mortality may exceed 90%. However, the incidence of SBP has been lowered to approx. 20% through early diagnosis and antibiotic therapy. Clinical awareness, prompt diagnosis, and immediate treatment are advised when caring for these patients to reduce mortality and morbidity. Aim: To discuss important issues comprising types of SBP, pathogenesis, bacteriology, including the emergence of multidrug-resistant (MDR) microorganisms, prompt diagnosis, risk factors, prognosis, treatment strategies, as well as recurrence prevention through antibiotic prophylaxis until liver transplantation and future trends in treating and preventing SBP in detail. Methods: This article is a literature review and appraisal of guidelines, randomized controlled trials, meta-analyses, and other review articles found on PubMed from between 1977 and 2022. Results: There are three types of SBP. Bacterial translocation from GI tract is the most common source of SBP. Therefore, two thirds of SBP cases were caused by Gram-negative bacilli, of which Escherichia coli is the most frequently isolated pathogen. However, a trend of Gram-positive cocci associated SBP has been demonstrated in recent years, possibly related to more invasive procedures and long-term quinolone prophylaxis. A diagnostic paracentesis should be performed in all patients with cirrhosis and ascites who require emergency room care or hospitalization, who demonstrate or report consistent signs/symptoms in order to confirm evidence of SBP. Distinguishing SBP from secondary bacterial peritonitis is essential because the conditions require different therapeutic strategies. The standard treatment for SBP is prompt broad-spectrum antibiotic administration and should be tailored according to community-acquired SBP, healthcare-associated or nosocomial SBP infections and local resistance profile. Albumin supplementation, especially in patients with renal impairment, is also beneficial. Selective intestinal decontamination is associated with a reduced risk of bacterial infection and mortality in high-risk group. Conclusions: The standard treatment for SBP is prompt broad-spectrum antibiotic administration and should be tailored according to community-acquired SBP, healthcare-associated or nosocomial SBP infections and local resistance profile. Since the one-year overall mortality rates for SBP range from 53.9 to 78%, liver transplantation should be seriously considered for SBP survivors who are good candidates for transplantation. Further development of non-antibiotic strategies based on pathogenic mechanisms are also urgently needed.

Clinical evaluation of bacterial DNA using an improved droplet digital PCR for spontaneous bacterial peritonitis diagnosis

Objective

Bacterial DNA (bactDNA) detection can be used to quickly identify pathogenic bacteria and has been studied on ascitic fluid. We aimed to retrospectively analyze the diagnostic value and applicational prospect of the bactDNA load in spontaneous bacterial peritonitis (SBP).

Method

We extracted viable bactDNA from ascitic samples of 250 patients with decompensated cirrhosis collected from October 2019 to April 2021 and detected the bactDNA by droplet digital polymerase chain reaction (ddPCR). We used ascitic samples of a baseline cohort of 191 patients to establish diagnostic thresholds for SBP and analyze the patients' diagnostic performance based on ascites polymorphonuclear (PMN) and clinical manifestation. We performed bactDNA quantification analysis on 13 patients with a PMN less than 250 cells/mm3 but with clinical symptoms. The dynamic changes of the bactDNA load from eight patients (before, during, and after SBP) were analyzed.

Results

After the removal of free DNA, the bactDNA detected by ddPCR was generally decreased (1.75 vs. 1.5 log copies/µl, P < 0.001). Compared with the traditional culture and PMN count in the SBP diagnosis, the bactDNA showed that the ddPCR sensitivity was 80.5%, specificity was 95.3%, positive predictive value was 82.5%, and negative predictive value was 94.7%, based on clinical composite criteria. In patients with a PMN less than 250 cells/mm3, the bactDNA load of 13 patients with symptoms was significantly higher than those without symptoms (2.7 vs. 1.7 log copies/µl, P < 0.001). The bactDNA in eight patients had SBP that decreased by 1.6 log copies/µl after 48 h of antibiotic treatment and by 1.0 log copies/µl after 3 days of continued treatment.

Conclusion

BactDNA detection can be used to further enhance the diagnostic efficiency of SBP. Therefore, the application of ddPCR assay not only can be used to discriminate and quantify bacteria but also can be used in the clinical assessment for antibiotics treatment.

Infection in Hospitalized Cirrhosis Patients: Changing Epidemiology and Clinical Features

BACKGROUND

Patients with cirrhosis are uniquely predisposed to infections, which can lead to acute decompensation and an increase in mortality rates. We hypothesized that not only are cirrhotic patients more likely to develop certain infections, but that specific infections are associated with poorer outcomes. Therefore, we aimed to examine the epidemiology, bacteriology, and outcomes of infections in cirrhotic patients admitted to the hospital.

METHODS

In this single center observational retrospective cohort study, we identified admissions in which patients had an infection from a group of all admissions of cirrhotics from 2011-2016. Infections were categorized by the primary source of infection, and rigorous clinical and bacteriologic definitions were used.

RESULTS

We identified 1,208 admissions in 877 unique patients during the study period. The most common infections identified were as follows: urinary tract infections (33%), pneumonia (23%), spontaneous bacterial peritonitis (14%), and bacteremia (11%). Gram-positive organisms were most commonly isolated in patients with spontaneous bacterial peritonitis and bacteremia, whereas gram-negative bacteria were most prevalent in urinary tract infections and pneumonia. Candida infections were common and identified in the following proportions: spontaneous bacterial peritonitis (16%), pneumonia (14%), bacteremia (13%), and urinary tract infections (9%). Pneumonia, spontaneous bacterial peritonitis, and meningitis were associated with increased mortality rates (29%, 32%, and 67%, respectively), compared to the overall mortality rate of 20% (p-value < 0.05).

CONCLUSIONS

In summary, infections were common in patients with cirrhosis and were associated with poor outcomes, particularly in the presence of evidence of sepsis. Spontaneous bacterial peritonitis and bacteremia are now most commonly due to gram-positive organisms and fungal infections appear to be rising in prevalence.

Fluoroquinolone-resistant strains in cirrhotic patients with spontaneous bacterial peritonitis: microbiological and molecular aspects

OBJECTIVES

This study aimed to determine the causative bacterial agents of spontaneous bacterial peritonitis (SBP) in patients with cirrhosis and to define antibiotic-resistance patterns in addition to identifying the genetic mutations in the quinolone resistance determining regions (QRDRs).

PATIENTS AND METHODS

Twenty milliliters of ascetic fluid was obtained from 51 patients with SBP. The antibiotic-sensitivity patterns of different strains were determined by the Kirby-Bauer method. Extracted bacterial DNA was used to determine the mutations in four different genes in QRDRs (gyrA, gyrB, parC, and parE) by sequencing after gene amplification by PCR.

RESULTS

Gram-negative bacilli were detected in 60.7% of the patients. Escherichia coli was detected in 33.3% of the patients, and Staphylococcus aureus was detected in 21.6%. Gram-negative bacilli showed the best sensitivity to meropenem (90.3%), followed by amikacin (83.9%). Gram-positive cocci were sensitive to vancomycin and oxacillin at 90 and 80%, respectively. Fluoroquinolone resistance was detected in 27% of the bacterial strains. Mutations in the gyrA and parC genes were detected in quinolone-resistant strains (64.3 and 35.7%, respectively). Several mutations were found in the gyrA gene (Ser83Leu, Ser81Phe, and Ser-84Leu). Ser80Ile and Ser79Tyr mutations were detected in the parC gene. No mutation was detected in the parE gene.

CONCLUSION

Frequent use of antibiotics as prophylaxis against SBP leads to an increase in antibiotic resistance and changes the microbial pattern of causative agents. The gyrA gene mutation was the most common mutation detected in fluoroquinolone-resistant strains.

Antimicrobial resistance in patients with decompensated liver cirrhosis and bacterial infections in a tertiary center in Northern Germany

Background and aims

Bacterial infections are common in patients with decompensated liver cirrhosis and a leading cause of death. Reliable data on antibiotic resistance are required to initiate effective empiric therapy. We here aim to assess the antimicrobial resistance profile of bacteria among patients with liver cirrhosis and infection.

Methods

Overall, 666 cirrhotic patients admitted to Hannover Medical School between January 2012 and April 2018 with ascites were assessed for bacterial infection. In case of infection, bacteria cultured from microbiological specimens of ascites, blood or urine were identified and analyzed for resistances against common antibiotic agents. Furthermore, analyses compared two periods of time and community-acquired vs. nosocomial infections.

Results

In 281 patients with infection, microbiological sampling was performed and culture-positive results were obtained in 56.9%. Multidrug-resistant (MDR)-bacteria were found in 54 patients (19.2%). Gram-positive organisms were more common (n = 141/261, 54.0%) and detected in 116/192 culture-positive infections (60.4%). Comparing infections before and after 2015, a numerical decline for MDR-bacteria (23.8% vs. 15.6%, p = 0.08) was observed with a significant decline in meropenem resistance (34.9% vs. 19.5%, p = 0.03). MDR-bacteria were more frequent in the case of nosocomial infections. Of note, in ascites the majority of the tested bacteria were resistant against ceftriaxone (73.8%) whereas significantly less were resistant against meropenem (27.0%) and vancomycin (25.9%).

Conclusions

In our tertiary center, distinct ratios of gram-positive infection with overall low ratios of MDR-bacteria were found. Adequate gram-positive coverage in the empiric therapy should be considered. Carbapenem treatment may be omitted even in nosocomial infection. In contrast, 3rd generation cephalosporins cannot be recommended even in community-acquired infection in our cirrhotic population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01871-w.

Intestinal Permeability Is a Mechanical Rheostat in the Pathogenesis of Liver Cirrhosis

Recent studies have suggested that an alteration in the gut microbiota and their products, particularly endotoxins derived from Gram-negative bacteria, may play a major role in the pathogenesis of liver diseases. Gut dysbiosis caused by a high-fat diet and alcohol consumption induces increased intestinal permeability, which means higher translocation of bacteria and their products and components, including endotoxins, the so-called "leaky gut". Clinical studies have found that plasma endotoxin levels are elevated in patients with chronic liver diseases, including alcoholic liver disease and nonalcoholic liver disease. A decrease in commensal nonpathogenic bacteria including Ruminococaceae and Lactobacillus and an overgrowth of pathogenic bacteria such as Bacteroidaceae and Enterobacteriaceae are observed in cirrhotic patients. The decreased diversity of the gut microbiota in cirrhotic patients before liver transplantation is also related to a higher incidence of post-transplant infections and cognitive impairment. The exposure to endotoxins activates macrophages via Toll-like receptor 4 (TLR4), leading to a greater production of proinflammatory cytokines and chemokines including tumor necrosis factor-alpha, interleukin (IL)-6, and IL-8, which play key roles in the progression of liver diseases. TLR4 is a major receptor activated by the binding of endotoxins in macrophages, and its downstream signal induces proinflammatory cytokines. The expression of TLR4 is also observed in nonimmune cells in the liver, such as hepatic stellate cells, which play a crucial role in the progression of liver fibrosis that develops into hepatocarcinogenesis, suggesting the importance of the interaction between endotoxemia and TLR4 signaling as a target for preventing liver disease progression. In this review, we summarize the findings for the role of gut-derived endotoxemia underlying the progression of liver pathogenesis.

Spontaneous bacterial peritonitis mortality trends of cirrhotic patients in the last decade in Constanta County

Spontaneous bacterial peritonitis (SBP) is a complication of liver cirrhosis with an increased in-hospital mortality rate. For this reason, the aim of the present study was to examine the main predictors of mortality in order to be able to identify high-risk patients in time and to guide the optimal treatment for prognosis improvement. We retrospectively collected demographic, clinical, laboratory and treatment data as well as data regarding length of stay and cost of hospitalization from 72 patients diagnosed with SBP between January 2010 and December 2019 in the Emergency Clinical Hospital St. Apostle Andrew, Constanta, Romania. Patients were divided into two groups: Those who survived and those who died. Logistic regression was used to identify a possible association between these factors and the increased risk of mortality. Univariate analysis revealed that clinical factors (fever, chills, and hepatic encephalopathy), biological factors such as serum and ascites leukocyte value, polymorphonuclear percentage (PMN), erythrocyte sedimentation rate (ESR) value, previous SBP episodes, and the presence of complications such as acute kidney injury (AKI), sepsis, and systemic inflammatory response syndrome (SIRS) were significantly associated with in-hospital mortality in patients with SBP. Multivariate analysis revealed that SIRS (P=0.0010) and fever (P=0.0258) were significantly associated with in-hospital mortality in patients with SBP. Findings of the present study suggest that, SIRS and fever were independent predictive factors of mortality in cirrhotic patients with SBP.

Characteristics and outcome of nosocomial bloodstream infection in patients with acute-on-chronic liver failure

AIM

Patients with acute-on-chronic liver failure (ACLF) have a high risk of developing infections while hospitalized. Nosocomial bloodstream infection (BSI) is not uncommon, particular in patients who receive invasive operation, which may have negative impact on prognosis. In this study, we aim to investigate the characteristics and short-term outcome of nosocomial BSI in patients with ACLF.

METHODS

Sixty-three patients with ACLF and nosocomial BSI from January 2014 to December 2015 were retrospectively studied. Clinical characteristics and distribution of bacteria at the time of BSI onset and short-term mortality were collected.

RESULTS

The most common etiology of ACLF was hepatitis B virus infection. Eighty-one percent of ACLF patients had other types of infections at BSI onset. Gram-negative bacteria (77.8%) were the main pathogens, among which Escherichia coli was responsible for 46.9%. Staphylococcus epidermidis was the main Gram-positive bacteria. The most prevalent multidrug resistance (MDR) bacteria was extended-spectrum β-lactamase (ESBL)-producing E. coli. The overall 28-day mortality rate was 42.9%. Multivariate analysis found that model for end-stage liver disease (MELD) score and number of organ failures were predictors of 28-day mortality. The area under the receiver operating characteristic of the numbers of organ failures to predict 28-day mortality was higher than MELD score (0.833 vs. 0.784, 0.4099), but without significant difference.

CONCLUSION

Gram-negative bacteria were the most prevalent pathogens and ESBL-producing bacteria were responsible for most of the MDR bacteria in patients with ACLF and nosocomial BSI. Higher MELD score and multiorgan failure were associated with worse outcomes.

Influenza B associated acute necrotising encephalopathy with visual impairment in a child

Influenza-associated encephalopathy/encephalitis (IAE) can result in serious neurological complications. We report a 4-year-old healthy female child with the diagnosis of IAE. Her clinical course was complicated by temporary visual impairment and significant motor deficits. Her unique ophthalmological findings have little precedent in previous literature.

Extended Infusion of β-Lactams for Bloodstream Infection in Patients With Liver Cirrhosis: An Observational Multicenter Study

BACKGROUND

We analyzed the impact of continuous/extended infusion (C/EI) vs intermittent infusion of piperacillin-tazobactam (TZP) and carbapenems on 30-day mortality of patients with liver cirrhosis and bloodstream infection (BSI).

METHODS

The BICRHOME study was a prospective, multicenter study that enrolled 312 cirrhotic patients with BSI. In this secondary analysis, we selected patients receiving TZP or carbapenems as adequate empirical treatment. The 30-day mortality of patients receiving C/EI or intermittent infusion of TZP or carbapenems was assessed with Kaplan-Meier curves, Cox-regression model, and estimation of the average treatment effect (ATE) using propensity score matching.

RESULTS

Overall, 119 patients received TZP or carbapenems as empirical treatment. Patients who received C/EI had a significantly lower mortality rate (16% vs 36%, P = .047). In a Cox-regression model, the administration of C/EI was associated with a significantly lower mortality (hazard ratio [HR], 0.41; 95% confidence interval [CI], 0.11-0.936; P = .04) when adjusted for severity of illness and an ATE of 25.6% reduction in 30-day mortality risk (95% CI, 18.9-32.3; P < .0001) estimated with propensity score matching. A significant reduction in 30-day mortality was also observed in the subgroups of patients with sepsis (HR, 0.21; 95% CI, 0.06-0.74), acute-on-chronic liver failure (HR, 0.29; 95% CI, 0.03-0.99), and a model for end-stage liver disease score ≥25 (HR, 0.26; 95% CI, 0.08-0.92). At competing risk analysis, C/EI of beta-lactams was associated with significantly higher rates of hospital discharge (subdistribution hazard [95% CI], 1.62 [1.06-2.47]).

CONCLUSIONS

C/EI of beta-lactams in cirrhotic patients with BSI may improve outcomes and facilitate earlier discharge.

Multivariate predictive model for asymptomatic spontaneous bacterial peritonitis in patients with liver cirrhosis

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a detrimental infection of the ascitic fluid in liver cirrhosis patients, with high mortality and morbidity. Early diagnosis and timely antibiotic administration have successfully decreased the mortality rate to 20%-25%. However, many patients cannot be diagnosed in the early stages due to the absence of classical SBP symptoms. Early diagnosis of asymptomatic SBP remains a great challenge in the clinic.

AIM

To establish a multivariate predictive model for early diagnosis of asymptomatic SBP using positive microbial cultures from liver cirrhosis patients with ascites.

METHODS

A total of 98 asymptomatic SBP patients and 98 ascites liver cirrhosis patients with negative microbial cultures were included in the case and control groups, respectively. Multiple linear stepwise regression analysis was performed to identify potential indicators for asymptomatic SBP diagnosis. The diagnostic performance of the model was estimated using the receiver operating characteristic curve.

RESULTS

Patients in the case group were more likely to have advanced disease stages, cirrhosis related-complications, worsened hematology and ascites, and higher mortality. Based on multivariate analysis, the predictive model was as follows: y (P) = 0.018 + 0.312 × MELD (model of end-stage liver disease) + 0.263 × PMN (ascites polymorphonuclear) + 0.184 × N (blood neutrophil percentage) + 0.233 × HCC (hepatocellular carcinoma) + 0.189 × renal dysfunction. The area under the curve value of the established model was 0.872, revealing its high diagnostic potential. The diagnostic sensitivity was 73.5% (72/98), the specificity was 86.7% (85/98), and the diagnostic efficacy was 80.1%.

CONCLUSION

Our predictive model is based on the MELD score, polymorphonuclear cells, blood N, hepatocellular carcinoma, and renal dysfunction. This model may improve the early diagnosis of asymptomatic SBP.

Current Status and Prospects of Spontaneous Peritonitis in Patients with Cirrhosis

Spontaneous bacterial peritonitis (SBP) is a common cirrhotic ascites complication which exacerbates the patient's condition. SBP is caused by gram-negative bacilli and, to a lesser extent, gram-positive cocci. Hospital-acquired infections show higher levels of drug-resistant bacteria. Geographical location influences pathogenic bacteria distribution; therefore, different hospitals in the same country record different bacteria strains. Intestinal changes and a weak immune system in patients with liver cirrhosis lead to bacterial translocation thus causing SBP. Early diagnosis and timely treatment are important in SBP management. When the treatment effect is not effective, other rare pathogens should be explored.

Lethal infective endocarditis due to Streptococcus agalactiae in a man with a history of alcohol abuse: A case report

RATIONAL

Infective endocarditis (IE) is defined as an infection of the endocardial surface of the heart, which may include one or more heart valves, the mural endocardium.

PATIENT CONCERNS

A 53-years-old man with a history of alcohol abuse was admitted in hospital for fever, paroxysmal atrial fibrillation cardioverted by Amiodarone and pulmonary infection.

DIAGNOSIS

A case of recurrent severe endocarditis, with neurological complications both ischemic and hemorrhagic and heart failure caused by Streptococcus agalactiae in healthy man we reported.

INTERVENTIONS

Surgery was performed 2 weeks after admission.

OUTCOMES

The onset of intracranial hemorrhage delayed second cardiac surgery and the patient died because of end-stage heart failure.

CONCLUSIONS

Infective endocarditis caused by S. agalactiae is very rare, particularly in patients without underlying structural heart disease. This study showed that IE due to S. Agalactiae is a disease with high mortality when associated with neurological complication, heart failure but especially when it is recurrent and hits valve prosthesis.

Role of Gut Dysbiosis in Liver Diseases: What Have We Learned So Far?

Accumulating evidence supports that gut dysbiosis may relate to various liver diseases. Alcoholics with high intestinal permeability had a decrease in the abundance of Ruminnococcus. Intestinal dysmotility, increased gastric pH, and altered immune responses in addition to environmental and genetic factors are likely to cause alcohol-associated gut microbial changes. Alcohol-induced dysbiosis may be associated with gut barrier dysfunction, as microbiota and their products modulate barrier function by affecting epithelial pro-inflammatory responses and mucosal repair functions. High levels of plasma endotoxin are detected in alcoholics, in moderate fatty liver to advanced cirrhosis. Decreased abundance of Faecalibacterium prausnitzii, an anti-inflammatory commensal, stimulating IL-10 secretion and inhibiting IL-12 and interferon-γ expression. Proteobacteria, Enterobacteriaceae, and Escherichia were reported to be increased in NAFLD (nonalcoholic fatty liver disease) patients. Increased abundance of fecal Escherichia to elevated blood alcohol levels in these patients and gut microbiota enriched in alcohol-producing bacteria produce more alcohol (alcohol hypothesis). Some undetermined pathological sequences related to gut dysbiosis may facilitate energy-producing and proinflammatory conditions for the progression of NAFLD. A shortage of autochthonous non-pathogenic bacteria and an overgrowth of potentially pathogenic bacteria are common findings in cirrhotic patients. The ratio of the amounts of beneficial autochthonous taxa (Lachnospiraceae + Ruminococaceae + Veillonellaceae + Clostridiales Incertae Sedis XIV) to those of potentially pathogenic taxa (Enterobacteriaceae + Bacteroidaceae) was low in those with early death and organ failure. Cirrhotic patients with decreased microbial diversity before liver transplantation were more likely to develop post-transplant infections and cognitive impairment related to residual dysbiosis. Patients with PSC had marked reduction of bacterial diversity. Enterococcus and Lactobacillus were increased in PSC patients (without liver cirrhosis.) Treatment-naive PBC patients were associated with altered composition and function of gut microbiota, as well as a lower level of diversity. As serum anti-gp210 antibody has been considered as an index of disease progression, relatively lower species richness and lower abundance of Faecalibacterium spp. in gp210-positive patients are interesting. The dysbiosis-induced altered bacterial metabolites such as a hepatocarcinogenesis promotor DCA, together with a leaky gut and bacterial translocation. Gut protective Akkermansia and butyrate-producing genera were decreased, while genera producing-lipopolysaccharide were increased in early hepatocellular carcinoma (HCC) patients.

Reevaluation of the impact of methicillin-resistance on outcomes in patients with Staphylococcus aureus bacteremia and endocarditis

BACKGROUND/AIMS

Methicillin-resistant Staphylococcus aureus (MRSA) is highly prevalent in hospitals, and has recently emerged in the community. The impact of methicillin-resistance on mortality and medical costs for patients with S. aureus bacteremia (SAB) requires reevaluation.

METHODS

We searched studies with SAB or endocarditis using electronic databases including Ovid-Medline, Embase-Medline, and Cochrane Library, as well as five local databases for published studies during the period January 2000 to September 2011.

RESULTS

A total of 2,841 studies were identified, 62 of which involved 17,563 adult subjects and were selected as eligible. A significant increase in overall mortality associated with MRSA, compared to that with methicillin-susceptible S. aureus (MSSA), was evidenced by an odds ratio (OR) of 1.95 (95% confidence interval [CI], 1.73 to 2.21; p < 0.01). In 13 endocarditis studies, MRSA increased the risk of mortality, with an OR of 2.65 (95% CI, 1.46 to 4.80). When three studies, which compared mortality rates between CA-MRSA and CA-MSSA, were combined, the risk of methicillin-resistance increased 3.23-fold compared to MSSA (95% CI, 1.25 to 8.34). The length of hospital stay in the MRSA group was 10 days longer than that in the MSSA group (95% CI, 3.36 to 16.70). Of six studies that reported medical costs, two were included in the analysis, which estimated medical costs to be $9,954.58 (95% CI, 8,951.99 to 10,957.17).

CONCLUSION

MRSA is still associated with increased mortality, longer hospital stays and medical costs, compared with MSSA in SAB in studies published since the year 2000.

Prevalence and Predictors of Third-Generation Cephalosporin Resistance in the Empirical Treatment of Spontaneous Bacterial Peritonitis

OBJECTIVE

To better characterize the changing patterns of spontaneous bacterial peritonitis (SBP) in a tertiary academic center in the United States by identifying the prevalence of gram-positive organisms and cephalosporin resistance along with predictors of mortality and antibiotic drug resistance.

PATIENTS AND METHODS

We reviewed 481 consecutive patients with SBP at Mayo Clinic in Rochester, Minnesota, from January 1, 2005, through December 31, 2016. Data on comorbid conditions, etiology of cirrhosis, factors predisposing to infection, and antimicrobial and antibiotic drug use were collected.

RESULTS

We identified 96 patients (20%) with culture-positive SBP requiring treatment (median age, 60 years; age range, 22-87 years; 44% men). Gram-positive organisms account for more than half of the cases. Overall resistance to third-generation cephalosporins was 10% (n=10). Risk factors for third-generation cephalosporin resistance include nosocomial acquisition, recent antibiotic drug use, and hepatocellular carcinoma. The negative predictive value for antibiotic drug resistance in the present model was 96% (70 of 73). Overall mortality at 30 and 90 days was 23% and 37%, respectively.

CONCLUSION

These findings support the recent observation of a rising prevalence of gram-positive organisms in SBP. Despite the changing pattern, third-generation cephalosporins seem to provide adequate empirical treatment in patients with community-acquired and health care-associated SBP without hepatocellular carcinoma.

Short- and long-term predictors of spontaneous bacterial peritonitis in Singapore

INTRODUCTION

Spontaneous bacterial peritonitis (SBP) is the commonest complication of liver cirrhosis. Timely and appropriate treatment of SBP is crucial, particularly with the rising worldwide prevalence of multidrug-resistant organisms (MDROs). We aimed to investigate the clinical outcomes of SBP in Singapore.

METHODS

All cirrhotic patients with SBP diagnosed between January 2014 and December 2017 were included. Nosocomial SBP (N-SBP) was defined as SBP diagnosed more than 48 hours after hospitalisation. Clinical outcomes were analysed as categorical outcomes using univariate and multivariate analysis.

RESULTS

There were 33 patients with 39 episodes of SBP. Their mean age was 64.5 years and 69.7% were male. The commonest aetiology of cirrhosis was hepatitis B (27.3%). The Median Model for End-stage Liver Disease (MELD) score was 17; 33.3% had acute-on-chronic liver failure and 60.6% had septic shock at presentation. N-SBP occurred in 25.6% of SBP cases. N-SBP was more commonly associated with MDROs, previous antibiotic use in the past three months (p = 0.014) and longer length of stay (p = 0.011). The 30-day and 90-day mortality among SBP patients was 30.8% and 51.3%, respectively. MELD score > 20 was a predictor for 30-day mortality. N-SBP and MELD score > 20 were predictors for 90-day mortality.

CONCLUSION

N-SBP was significantly associated with recent antibiotic use, longer hospitalisation, more resistant organisms and poorer survival among patients with SBP. N-SBP and MELD score predict higher mortality in SBP. Judicious use of antibiotics may reduce N-SBP and improve survival among cirrhotic patients.

Spontaneous bacterial peritonitis caused by Gram-negative bacteria: an update of epidemiology and antimicrobial treatments

Introduction: Spontaneous bacterial peritonitis (SBP) is a main infectious complication in end-stage liver disease (ESLD) patients. The increasing trend of bacterial resistance in ESLD patients with SBP has been associated with low treatment efficacy of traditional therapy. Cephalosporin use has been restricted to community-acquired infections and in areas/health care settings with low rates of multidrug-resistant (MDR) bacteria. To date, several changes are necessary with regard to empiric therapy recommendations in areas/health care settings with high rates of MDR bacteria. Areas covered: An overview of the epidemiology and antimicrobial treatments of SBP caused by Gram-negative bacteria. Expert opinion: Broad-spectrum antibiotics have been recommended as empiric therapy for suspected SBP in areas/health care settings with high rates of MDR bacteria and secondary treatment, with newer antibiotics, for SBP caused by MDR-Gram-negative bacteria (i.e. new beta-lactam/beta-lactamase inhibitor combinations, cefiderocol, plazomicin, and eravacycline) either alone or in combination.

Multidrug-resistant bacterial infections in patients with decompensated cirrhosis and with acute-on-chronic liver failure in Europe

BACKGROUND & AIMS

Antibiotic resistance has been increasingly reported in patients with decompensated cirrhosis in single-center studies. Prospective investigations reporting broad epidemiological data are scarce. We aimed to analyze epidemiological changes in bacterial infections in patients with decompensated cirrhosis.

METHODS

This was a prospective evaluation of 2 series of patients hospitalized with decompensated cirrhosis. The Canonic series included 1,146 patients from Northern, Southern and Western Europe in 2011. Data on epidemiology, clinical characteristics of bacterial infections, microbiology and empirical antibiotic schedules were assessed. A second series of 883 patients from Eastern, Southern and Western Europe was investigated between 2017-2018.

RESULTS

A total of 455 patients developed 520 infections (39.7%) in the first series, with spontaneous bacterial peritonitis, urinary tract infections and pneumonia the most frequent infections. Nosocomial episodes predominated in this series. Nearly half of the infections were culture-positive, of which 29.2% were caused by multidrug-resistant organisms (MDROs). MDR strains were more frequently isolated in Northern and Western Europe. Extended-spectrum beta-lactamase-producing Enterobacteriaceae were the most frequent MDROs isolated in this series, although prevalence and type differed markedly among countries and centers. Antibiotic resistance was associated with poor prognosis and failure of antibiotic strategies, based on third-generation cephalosporins or quinolones. Nosocomial infection (odds ratio [OR] 2.74; p < 0.001), intensive care unit admission (OR 2.09; p = 0.02), and recent hospitalization (OR 1.93; p = 0.04) were identified as independent predictors of MDR infection. The prevalence of MDROs in the second series (392 infections/284 patients) was 23%; 38% in culture-positive infections. A mild increase in the rate of carbapenem-resistant Enterobacteriaceae was observed in this series.

CONCLUSIONS

MDR bacterial infections constitute a prevalent, growing and complex healthcare problem in patients with decompensated cirrhosis and acute-on-chronic liver failure across Europe, negatively impacting on prognosis. Strategies aimed at preventing the spread of antibiotic resistance in cirrhosis should be urgently evaluated.

LAY SUMMARY

Infections caused by bacteria resistant to the main antibiotic families are prevalent in patients with cirrhosis. This study demonstrates that this healthcare problem is increasing and extends through all European regions. Infections caused by these difficult to treat bacteria resolve less frequently and often cause the death of the patient. The type of resistant bacteria varies markedly among different hospitals.

Infections in Liver Transplantation

Liver transplantation has become an important treatment modality for patients with end-stage liver disease/cirrhosis, acute liver failure, and hepatocellular carcinoma. Although surgical techniques and immunosuppressive regimens for liver transplantation have improved significantly over the past 20 years, infectious complications continue to contribute to the morbidity and mortality in this patient population. The use of standardized screening protocols for both donors and recipients, coupled with targeted prophylaxis against specific pathogens, has helped to mitigate the risk of infection in liver transplant recipients. Patients with chronic liver disease and cirrhosis have immunological deficits that place them at increased risk for infection while awaiting liver transplantation. The patient undergoing liver transplantation is prone to develop healthcare-acquired infections due to multidrug-resistant organisms that could potentially affect patient outcomes after transplantation. The complex nature of liver transplant surgery that involves multiple vascular and hepatobiliary anastomoses further increases the risk of infection after liver transplantation. During the early post-transplantation period, healthcare-acquired bacterial and fungal infections are the most common types of infection encountered in liver transplant recipients. The period of maximal immunosuppression that occurs at 1–6 months after transplantation can be complicated by opportunistic infections due to both primary infection and reactivation of latent infection. Severe community-acquired infections can complicate the course of liver transplantation beyond 12 months after transplant surgery. This chapter provides an overview of liver transplantation including indications, donor-recipient selection criteria, surgical procedures, and immunosuppressive therapies. A focus on infections in patients with chronic liver disease/cirrhosis and an overview of the specific infectious complications in liver transplant recipients are presented.

Spontaneous bacterial peritonitis - therapeutic challenges in the era of increasing drug resistance of bacteria

Spontaneous bacterial peritonitis (SBP) is one of the most common bacterial infections in patients with liver cirrhosis and it significantly contributes to the deterioration of the prognosis and increased risk of mortality. Previous data suggested that the most common pathogens causing SBP are G-negative aerobic bacteria and treatment recommended by the international guidelines (EASL, AASLD) is highly effective.

In recent years, due to the widespread use of antibiotic prophylaxis and the increased frequency of hospitalization along with the use of invasive procedures in patients with cirrhosis, the involvement of Gram-positive cocci and multi-drug resistant bacteria in the etiology of SBP is increasing. This is related to the lowering of the effectiveness of the first-line therapy used so far and worsening of the prognosis, increasing in-hospital mortality. In this work we summarize current data on the characteristics of pathogens responsible for SBP in the context of currently recommended treatment regimens.

Management of Infectious Complications Associated with Acute-on-Chronic Liver Failure

Introduction

Acute-on-chronic liver failure (ACLF) is associated with a high susceptibility to infections leading to complications and poor prognosis. The sensitized immune system overwhelmingly responds to invading bacteria leading to organ damage. After resolution of infection or prolonged disease duration, the phagocytic system becomes irresponsive with a reduced bacterial clearance capacity promoting secondary infection.

Methods

This review focuses on the best management strategies for patients with ACLF and infections. Using the following terms, an extensive literature research on the Medline database was performed: 'acute-on-chronic liver failure', 'infection', 'ACLF', 'bacteria', 'multi-resistance'.

Results

Analysis of the literature confirmed that delayed diagnosis and treatment of infections in patients with ACLF results in a poor prognosis. Patients with ACLF should be considered as having a potential infection and should undergo a complete screening for sepsis. Once biochemical analysis indicates a potential infection, such as abnormal levels of C-reactive protein and procalcitonin, antibiotic treatment should be initiated immediately without microbiological culture results. For community-acquired infections third-generation cephalosporins are still the first choice, whereas in the nosocomial setting antibiotics with broader spectrum, such as piperacillin/combactam or carbapenems ± glycopeptides, are preferred. The patient should be re-assessed 48 h after treatment initiation in order to tailor the treatment. Non-response is suspicious, likely due to bacterial resistance or fungal infection, which should be considered when choosing further treatment strategies. Albumin substitution to prevent hepatorenal syndrome and to improve patients' outcome is mandatory in patients with spontaneous bacterial peritonitis. Prophylactic antibiotic therapy is suitable to prevent infections in high-risk patients.

Conclusion

The screening for infections and its treatment is an essential part of managing patients with ACLF. In order to improve patients' prognosis, antibiotic treatment should be initiated once an infection is suspected. However, preventive strategies are already established and should be applied according to the guidelines.

Clinical and bacteriological features and prognosis of ascitic fluid infection in Chinese patients with cirrhosis

Background

Spontaneous bacterial peritonitis (SBP) and bacterascites (BA) represent frequent and serious complications in cirrhosis patients with ascites. However, few detailed data are available regarding the clinical and bacteriological feature of SBP or BA patients in China.

Methods

We retrospectively analyzed bacteriological and clinical characteristics of patients with SBP and BA at Beijing 302 Hospital in China from January 2012 to December 2015.

Results

A total of 600 patients with SBP (n = 408) or BA (n = 192) were enrolled. Patients with BA appeared to have a less severe clinical manifestation and lower mortality rate than patients with SBP. Gram-negative bacteria formed the majority of pathogens in SBP (73.9%) and BA (55.8%) cases. Higher ascitic fluid polymorphonuclear leucocytes (PMN) count and hepatocellular carcinoma were independent risk factors for BA episode progressing to SBP. The concentration of blood urea nitrogen (BUN) was independent risk factor for 30-day mortality of BA patients. For patients with SBP, the independent risk factors for 30-day mortality were age, Model for End-Stage Liver Disease (MELD) score, septic shock and hepatocellular carcinoma. Patients with third-generation cephalosporin or carbapenems resistant infection had a significantly lower survival probability. There were significant differences in clinical characteristics and outcome among the major bacteria. Multivariate analysis showed that patients infected with Klebsiella spp. had higher hazard ratio of 30-day mortality.

Conclusion

Our study reported the bacteriological and clinical characteristics of patients with SBP and BA. Higher ascitic fluid PMN count and hepatocellular carcinoma were found to be independent risk factors for BA episode progressed to SBP. Outcome of ascitic fluid infection in patients with cirrhosis was influenced by the type of bacteria and antimicrobial susceptibility.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3101-1) contains supplementary material, which is available to authorized users.

Methicillin-resistant Staphylococcus aureus bacteremia among liver transplant recipients: epidemiology and associated risk factors for morbidity and mortality

Bacteremia due to Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA), complicates the clinical course of liver transplantation and is associated with high morbidity and mortality. Intravascular catheters had been reported to be the most frequent source of MRSA bacteremia. Among bacteremic liver recipients, 26.3%-100% of S. aureus were MRSA. Previous studies identified pre-transplant and post-transplant acquired S. aureus carriage, greater severity of liver disease, hepatocellular carcinoma and infection with immuno-modulatory viruses as predictors of S. aureus bacteremia in liver recipients. MRSA bacteremia accompanied by pneumonia and abdominal infections was related to mortality. Vancomycin, as well as daptomycin, is a first-line antibiotic for MRSA bacteremia. The purpose of this review is to better understand the characteristics of MRSA bacteremia by summarizing the epidemiology and antimicrobial resistance of S. aureus, the primary source, and related risk factors for morbidity and mortality of MRSA bacteremia. We have also explored the diagnostic, therapeutic and preventive measures for MRSA bacteremia to improve the outcomes of liver recipients.

Opportunistic infections in end stage liver disease

Liver cirrhosis is the 10th most common cause of death in Western world and infection is associated with a high morbidity and mortality, and represents the leading cause of acute liver decompensation. Patients with end-stage liver disease exhibit an important impairment of immune system. This condition, called cirrhosis-associated immune dysfunction, summarizes both local and systemic immune system alterations in liver cirrhosis that play a pivotal role in determining both the high incidence of infections and the ominous infections related mortality in this population. Another concerning feature of infections in cirrhotic patients is the growing prevalence of multidrug- resistant or extensively drug-resistant pathogens, which are associated with higher mortality, increased length of in-hospital stay and higher healthcare related costs if compared with infection caused by susceptible strains. Finally, patient with liver cirrhosis have several unique pathophysiological characteristics including hypoalbuminemia and reduction binding to proteins; altered distribution; altered clearance of the antimicrobials that can affect the pharmacokinetic/ pharmacodynamic of antimicrobials.

Management of bacterial infection in the liver transplant candidate

Bacterial infection (BI) is a common cause of impairment of liver function in patients with cirrhosis, especially in the liver transplant candidates. These patients share an immunocompromised state and increased susceptibility to develop community and hospital-acquired infections. The changing epidemiology of BI, with an increase of multidrug resistant strains, especially in healthcare-associated settings, represents a critical issue both in the waiting list and in the post-operative management. This review focused on the role played by BI in patients awaiting liver transplantation, evaluating the risk of drop-out from the waiting list, the possibility to undergo liver transplantation after recovery from infection or during a controlled infection.

Fulminant ulcerative colitis complicated by treatment-refractory bacteremia

Severe ulcerative colitis is defined by more than six bloody stools daily and evidence of toxicity, demonstrated by fever, tachycardia, anemia, or an elevated erythrocyte sedimentation rate. Fulminant disease represents a subset of severe disease with signs and symptoms suggestive of increased toxicity. Treatment of severe colitis includes intravenous corticosteroid administration, with consideration of intravenous infliximab 5 mg/kg. Failure to show improvement after 3 to 5 days is an indication for colectomy or treatment with intravenous cyclosporine. We report a 23-year-old Hispanic woman with decompensated cirrhosis presenting with new-onset fulminant ulcerative colitis and resulting polymicrobial bacteremia, requiring colectomy for infection source control and colitis treatment.

Evaluation of prognostic scoring systems in liver cirrhosis patients with bloodstream infection

Patients with cirrhosis are at increased risk of developing bloodstream infections (BSIs), and the short-term mortality rate in those patients is high. The aim of this study was to compare the different scoring models to predict mortality in cirrhotic patients with BSIs.A total of 222 cirrhotic patients with BSIs were retrospectively included in the study. The demographic, clinical, and microbiologic data were collected and patients were followed for at least 28 days after blood cultures were established. A multivariable Cox proportional hazard model was used to identify independent risk factors for 28-day all-cause mortality. The prognostic accuracy of different scoring models (chronic liver failure-organ failure [CLIF-OF], model for end-stage liver disease [MELD], systemic inflammatory response syndrome [SIRS], and Pitt scores) were compared with the C-index and receiver operating characteristic curve (ROC).Forty deaths were recorded on day 28 after blood cultures were established. Male sex (hazard ratio [HR] = 2.75, 95% confidence interval [CI] = 1.10-6.86), international normalized ratio (INR) (HR = 1.76, 95% CI = 1.35-2.30), serum bilirubin (HR = 1.002, 95% CI = 1.000-1.003), circulation failure (HR = 3.56, 95% CI = 1.63-7.79), lung failure (HR = 2.23, 95% CI = 1.09-4.57), and non-primary BSI source (HR = 2.27, 95% CI = 1.09-4.73) were identified as independent risk factors for mortality in cirrhotic patients with BSIs. In predicting 28-day mortality, CLIF-OF and MELD scores had significantly high C-indices (0.79 and 0.76, respectively) and ROC values (0.786 and 0.782, respectively) compared with Pitt and SIRS scores (C-indices: 0.61 and 0.57, respectively; ROC values: 0.591 and 0.637, respectively).Cirrhotic patients with BSIs had high short-term mortality rates. Our data suggested that both CLIF-OF and MELD scores can be used to predict the short-term prognosis of these patients.

Current concepts and future strategies in the antimicrobial therapy of emerging Gram-positive spontaneous bacterial peritonitis

Spontaneous bacterial peritonitis (SBP) is the most common infection in end-stage liver disease patients. SBP is defined as an ascitic fluid infection with a polymorphonuclear leucocyte count ≥ 250/mm3 without an evident intra-abdominal surgically treatable source. Several mechanisms contribute to SBP occurrence, including translocation of gut bacteria and their products, reduced intestinal motility provoking bacterial overgrowth, alteration of the gut's barrier function and local immune responses. Historically, Gram-negative enteric bacteria have been the main causative agents of SBP, thereby guiding the empirical therapeutic choice. However, over the last decade, a worryingly increasing prevalence of Gram-positive and multi-drug resistant (MDR) SBP has been seen. Recently, the microbiological spectrum of SBP seems to have changed in Europe due to a high prevalence of Gram-positive bacteria (48%-62%). The overall proportion of MDR bacteria is up to 22%-73% of cases. Consequently, empirical therapy based on third-generation cephalosporins or amoxicillin/clavulanic acid, can no longer be considered the standard of care, as these drugs are associated with poor outcomes. The aim of this review is to describe, with an epidemiological focus, the evidence behind this rise in Gram-positive and MDR SBP from 2000 to present, and illustrate potential targeted therapeutic strategies. An appropriate treatment protocol should include daptomycin plus ceftaroline and meropenem, with prompt stepdown to a narrower spectrum when cultures and sensitivity data are available in order to reduce both cost and potential antibiotic resistance development.

Epidemiology and management of healthcare-associated bloodstream infections in non-neutropenic immunosuppressed patients: a review of the literature

Advancements in medicine have led to a considerable increase in the proportion of patients living with severe chronic diseases, malignancies, and HIV infections. Most of these conditions are associated with acquired immune-deficient states and treatment-related immunosuppression. Although infections as a result of neutropenia have long been recognized and strategies for management were developed, non-neutropenic immunosuppression has been overlooked. Recently, community-acquired infections in patients with frequent, significant exposure to healthcare settings and procedures have been classified as 'healthcare-associated infections' since they are more similar to hospital-acquired infections. Most of the non-neutropenic immunosuppressed patients have frequent contact with the healthcare system due to their chronic and severe diseases. In this review, we focus on the healthcare-associated bloodstream infections in the most common non-neutropenic immunosuppressive states and provide an update of the recent evidence for the management of these infections.

Gut Microbiome-based Therapeutics in Liver Cirrhosis: Basic Consideration for the Next Step

Infections account for significant morbidity and mortality in liver cirrhosis and most are related to the gut microbiome. Fecal dysbiosis, characterized by an overgrowth of potentially pathogenic bacteria and a decrease in autochthonous non-pathogenic bacteria, becomes prominent with the progression of liver cirrhosis. In cirrhotic patients, disruption of the intestinal barrier causes intestinal hyperpermeability (i.e. leaky gut), which is closely related to gut dysmotility, dysbiosis and small intestinal bacterial overgrowth and may induce pathological bacterial translocation. Although the involved microbial taxa are somewhat different between the cirrhotic patients from the East and the West, the common manifestation of a shortage of bacteria that contribute to the production of short-chain fatty acids and secondary bile acids may facilitate intestinal inflammation, leaky gut and gut dysbiosis. Translocated endotoxin and bacterial DNA are capable of provoking potent inflammation and affecting the metabolic and hemodynamic systems, which may ultimately enhance the progression of liver cirrhosis and its various complications, such as hepatic encephalopathy (HE), variceal bleeding, infection and renal disturbances. Among studies on the microbiome-based therapeutics, findings of probiotic effects on HE have been contradictory in spite of several supportive results. However, the effects of synbiotics and prebiotics are substantially documented. The background of their effectiveness should be evaluated again in relation to the cirrhosis-related changes in gut microbiome and their metabolic effects. Strict indications for the antibiotic rifaximin remain unestablished, although its effect is promising, improving HE and other complications with little influence on microbial populations. The final goal of microbiome-based therapeutics is to adjust the gut-liver axis to the maximal benefit of cirrhotic patients, with the aid of evolving metagenomic and metabolomic analyses.

Comparative Study of Community Acquired and Nosocomial Spontaneous Bacterial Peritonitis and its Variants in 150 Patients

BACKGROUND

Nosocomial acquisition of spontaneous bacterial peritonitis (SBP) is debated as having a different microbial etiology and prognosis. Identification of clinical, laboratory predictors of mortality and appropriate empirical antimicrobial selection is necessary to prevent early mortality and morbidity. We aimed to find the clinical and bacteriological profile in nosocomial and community acquired SBP and its variants, and the predictors of mortality.

MATERIAL AND METHODS

One hundred and fifty patients with 162 discrete episodes of different types of SBP were analyzed. Relevant clinical and laboratory data were analyzed. SBP was diagnosed according to standard criteria and classified as community acquired if the infection detected within 48 h of admission and as nosocomial after 48 h of admission to the hospital.

RESULTS

Eighty seven percent had community acquired SBP (CSBP), 13% had nosocomial SBP (NSBP). Patients of NSBP were older, had more episodes of GI bleed and higher previous episodes of encephalopathy. Patients who died were older, had worse encephalopathy. NSBP had higher one month mortality. Age, serum sodium, encephalopathy and NSBP predicted mortality. Culture positivity was 22.22%. Escherichia coli was the commonest organism isolated. There was no difference in the bacteriological profile between CSBP and NSBP. E. coli showed up to 48% resistance to third generation cephalosporins. Overall sensitivity to aminoglycosides was more than 75%.

CONCLUSIONS

Overall mortality was 59%. NSBP had significantly high one month mortality. Age, serum sodium, encephalopathy and NSBP were predictors of mortality. Bacteriological profile was similar between CSBP and NSBP.

Neutrophil-lymphocyte ratio predicts hospital-acquired bacterial infections in decompensated cirrhosis

BACKGROUND

Bacterial infection is a frequent complication and severe burden in cirrhotic patients. We determined the utility of neutrophil-to-lymphocyte ratio (NLR) to predict the hospital-acquired (HA) bacterial infections episode in patients with decompensated cirrhosis.

METHODS

We retrospectively included 2066 consecutive decompensated cirrhotic patients from two separate tertiary hospitals, divided into training (n=1377) and validation (n=689) set. All data were collected on admission and all overt bacterial infections occurring after >48h of hospital stay were registered.

RESULTS

The incidence of HA bacterial infections in training and validation cohort was 35.87% and 31.05% respectively. Multivariate analysis showed that total bilirubin (TBil), albumin, white blood cell count (WBC) and NLR were independent predictors of HA bacterial infections. We established a Model_NTWA using these four variables and a Model_TWA which did not include NLR. Areas under the curves (AUC) of Model_NTWA (0.859) and NLR (0.824) were higher than which of Model_TWA (0.713), WBC (0.675), TBil (0.593) and Albumin (0.583). Consistent with training cohort, validation cohort showed similar results. Patients with NLR of at least 4.33 had a significantly lower survival (P<0.001).

CONCLUSIONS

NLR can be used as a novel noninvasive marker to predict the occurrence of HA bacterial infections in decompensated cirrhotic patients.

The impact of infection by multidrug-resistant agents in patients with cirrhosis. A multicenter prospective study

BACKGROUND & AIMS

Bacterial strains resistant to antibiotics are a serious clinical challenge. We assessed the antibiotic susceptibility of bacteria isolated from infections in patients with cirrhosis by a multicentre investigation.

RESULTS

Three hundred and thirteen culture-positive infections (173 community acquired [CA] and 140 hospital acquired [HA]) were identified in 308 patients. Urinary tract infections, spontaneous bacterial peritonitis and bacteremias were the most frequent. Quinolone-resistant Gram-negative isolates were 48%, 44% were extended-spectrum beta-lactamase producers and 9% carbapenem resistant. In 83/313 culture-positive infections (27%), multidrug-resistant agents (MDRA) were isolated. This prevalence did not differ between CA and HA infections. MDRA were identified in 17 of 37 patients on quinolone prophylaxis, and in 46 of 166 not on prophylaxis (45% vs 27%; P<.03). In 287 cases an empiric antibiotic therapy was undertaken, in 37 (12.9%) this therapy failed. The in-hospital mortality rate of this subset of patients was significantly higher compared to patients who received an effective broad(er)-spectrum therapy (P=.038). During a 3-month follow-up, 56/203 culture-positive patients (27.6%) died, 24/63 who have had MDRA-related infections (38%) and 32/140 who have had antibiotic-susceptible infections (22.8%) (P=.025). Multivariate analysis disclosed MDRA infection, age, hepatocellular carcinoma, bilirubin, international normalized ratio and the occurrence of portal hypertension-related complications independent predictors of death.

CONCLUSIONS

Infection by MDRA is frequent in patients with cirrhosis and the prognosis is severe, especially in patients unresponsive to empiric antibiotic therapy.

The challenges of multi-drug-resistance in hepatology

Antimicrobial resistance has become a major global public health security problem that needs coordinated approaches at regional, national and international levels. Antibiotic overuse and the failure of control measures to prevent the spread of resistant bacteria in the healthcare environment have led to an alarming increase in the number of infections caused by resistant bacteria, organisms that resist many (multi-drug and extensively drug-resistant strains), if not all (pan-drug-resistant bacteria) currently available antibiotics. While Gram-positive cocci resistance (methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci) shows a heterogeneous geographical distribution, extended-spectrum β-lactamase-producing Enterobacteriaceae and carbapenem-resistant Enterobacteriaceae have become pandemic worldwide and endemic in some parts of the world, respectively. Moreover, currently available therapeutic options for resistant bacteria are very limited, with very few new agents in development. Antimicrobial resistance is especially relevant in decompensated cirrhosis. Firstly, cirrhotic patients are highly susceptible to develop infections caused by resistant bacteria as risk factors of multiresistance concentrate in this population (mainly repeated hospitalizations and antibiotic exposure). Secondly, inappropriate empirical antibiotic schedules easily translate into increased morbidity (acute kidney injury, acute-on-chronic liver failure, septic shock) and hospital mortality in advanced cirrhosis. Therefore, hepatologists must face nowadays a complex clinical scenario that requires new empirical antibiotic strategies that may further spread resistance. Global, regional and local preventive measures should therefore be implemented to combat antimicrobial resistance in cirrhosis including the restriction of antibiotic prophylaxis to high-risk populations, investigation on non-antibiotic prophylaxis, stewardship programs on adequate antibiotic prescription and on increasing awareness of the problem among health professionals, and well-defined early de-escalation policies based on rapid microbiological diagnostic tests. Other infection control practices such as hand hygiene and barrier precautions are also important. Clinical impact and cost-effectiveness of epidemiological surveillance programs (periodic rectal and nasal swabs) should also be explored.

Microbiology and resistance in first episodes of spontaneous bacterial peritonitis: implications for management and prognosis

PURPOSE

International guidelines for antibiotic treatment of spontaneous bacterial peritonitis (SBP) are based on studies conducted decades ago and do not reflect regional differences of bacterial epidemiology.

METHODS

We retrospectively analyzed epidemiology of agents, antibiotic resistance patterns, and survival in liver cirrhosis patients with their first episode of SBP during the years 2007-2013.

RESULTS

Of the 311 patients included, 114 patients had a positive ascites culture, and 197 had an ascitic neutrophil count >250 μL. Gram-positive bacteria (47.8%) were more frequently found than Gram-negatives (44.9%), fungi in 7.2%. Enterobacter spp. (40.6%), Enterococcus spp. (26.1%), and Staphylcoccus spp. (13.8%) were the most frequently isolated agents. Third-generation cephalosporins covered 70.2% of non-nosocomial and 56.3% of nosocomial-acquired SBP cases.When SBP was diagnosed by a positive ascitic culture, survival was highly significantly reduced (mean: 13.9 ± 2.9 months; 95% confidence interval [CI]: 8.1-19.8) compared with culture-negative SBP patients (mean: 44.1 ± 5.4 months; 95% CI: 33.4-54.9; P = 0.000). Along with model of end-stage liver disease score and intensive care unit contact, a positive ascites culture remained an independent risk factor associated with poor survival (odds ratio: 1.49; 95% CI: 1.09-2.03) in multivariate analysis; piperacillin/tazobactam proved to be an adequate antibiotic for nosocomial and non-nosocomial SBP in 85.1% and 92.5%, respectively. SBP infection with Enterococcus spp. was associated with poor patient survival (P = 0.048).

CONCLUSIONS

Third-generation cephalosporins have poor microbial coverage for treatment of SBP. Current guidelines need to adapt for the emerging number of Gram-positive infectious agents in SBP patients.

The empirical antibiotic treatment of nosocomial spontaneous bacterial peritonitis: Results of a randomized, controlled clinical trial

Spontaneous bacterial peritonitis (SBP) is a common, life-threatening complication of liver cirrhosis. Third-generation cephalosporins have been considered the first-line treatment of SBP. In 2014, a panel of experts suggested a broader spectrum antibiotic regimen for nosocomial SBP, according to the high rate of bacteria resistant to third-generation cephalosporins found in these patients. However, a broader-spectrum antibiotic regimen has never been compared to third-generation cephalosporins in the treatment of nosocomial SBP. The aim of our study was to compare meropenem plus daptomycin versus ceftazidime in the treatment of nosocomial SBP. Patients with cirrhosis and nosocomial SBP were randomized to receive meropenem (1 g/8 hours) plus daptomycin (6 mg/kg/day) or ceftazidime (2 g/8 hours). A paracentesis was performed after 48 hours of treatment. A reduction in ascitic fluid neutrophil count <25% of pretreatment value was considered a treatment failure. The primary outcome was the efficacy of treatment defined by the resolution of SBP after 7 days of treatment. Thirty-two patients were randomized and 31 were analyzed. The combination of meropenem plus daptomycin was significantly more effective than ceftazidime in the treatment of nosocomial SBP (86.7 vs. 25%; P < 0.001). Ninety-day transplant-free survival (TFS) was not significantly different between the two groups. In the multivariate analysis, ineffective response to first-line treatment (hazard ratio [HR]: 20.6; P = 0.01), development of acute kidney injury during hospitalization (HR: 23.2; P = 0.01), and baseline mean arterial pressure (HR: 0.92; P = 0.01) were found to be independent predictors of 90-day TFS.

CONCLUSION

The combination of meropenem plus daptomycin is more effective than ceftazidime as empirical antibiotic treatment of nosocomial SBP. Efficacy of the empirical antibiotic treatment is a strong predictor of 90-day survival in patients with nosocomial SBP.

Bacterial infections in cirrhosis: A critical review and practical guidance

Bacterial infection is common and accounts for major morbidity and mortality in cirrhosis. Patients with cirrhosis are immunocompromised and increased susceptibility to develop spontaneous bacterial infections, hospital-acquired infections, and a variety of infections from uncommon pathogens. Once infection develops, the excessive response of pro-inflammatory cytokines on a pre-existing hemodynamic dysfunction in cirrhosis further predispose the development of serious complications such as shock, acute-on-chronic liver failure, renal failure, and death. Spontaneous bacterial peritonitis and bacteremia are common in patients with advanced cirrhosis, and are important prognostic landmarks in the natural history of cirrhosis. Notably, the incidence of infections from resistant bacteria has increased significantly in healthcare-associated settings. Serum biomarkers such as procalcitonin may help to improve the diagnosis of bacterial infection. Preventive measures (e.g., avoidance, antibiotic prophylaxis, and vaccination), early recognition, and proper management are required in order to minimize morbidity and mortality of infections in cirrhosis.

Liver Cirrhosis and Diabetes Mellitus Are Risk Factors for Staphylococcus aureus Infection in Patients with Healthcare-Associated or Hospital-Acquired Pneumonia

Background. The risk factors for Staphylococcus aureus (S. aureus) pneumonia are not fully identified. The aim of this work was to find out the clinical characteristics associated with S. aureus infection in patients with healthcare-associated pneumonia (HCAP) and hospital-acquired pneumonia (HAP), which may be applicable for more appropriate selection of empiric antibiotic therapy. Methods. From July 2007 to June 2010, patients who were admitted to the intensive care unit with severe HCAP/HAP and severe sepsis were enrolled in this study. Lower respiratory tract sample was semiquantitatively cultured. Initial broad-spectrum antibiotics were chosen by Taiwan or American guidelines for pneumonia management. Standard bundle therapies were provided to all patients according to the guidelines of the Surviving Sepsis Campaign. Results. The most frequently isolated pathogens were Pseudomonas aeruginosa, S. aureus, Acinetobacter baumannii, Klebsiella pneumoniae, and Escherichia coli. Patients with positive isolation of S. aureus in culture had significantly higher history of liver cirrhosis and diabetes mellitus, with odds ratios of 3.098 and 1.899, respectively. The S. aureus pneumonia was not correlated with history of chronic obstructive pulmonary disease, hypertension, and hemodialysis. Conclusion. Liver cirrhosis and diabetes mellitus may be risk factors for S. aureus infection in patients with severe HCAP or HAP.

Bloodstream infections in patients with liver cirrhosis

Bloodstream infections are a serious complication in patients with liver cirrhosis. Dysregulated intestinal bacterial translocation is the predominant pathophysiological mechanism of infections in this setting. For this reason enteric Gram-negative bacteria are commonly encountered as the first etiological cause of infection. However, through the years, the improvement in the management of cirrhosis, the recourse to invasive procedures and the global spread of multidrug resistant pathogens have importantly changed the current epidemiology. Bloodstream infections in cirrhotic patients are characterized by high mortality rate and complications including metastatic infections, infective endocarditis, and endotipsitis (or transjugular intrahepatic portosystemic shunt-related infection). For this reason early identification of patients at risk for mortality and appropriated therapeutic management is mandatory. Liver cirrhosis can significantly change the pharmacokinetic behavior of antimicrobials. In fact hypoproteinaemia, ascitis and third space expansion and impairment of renal function can be translated in an unpredictable drug exposure.

A quick screening model for symptomatic bacterascites in cirrhosis

BACKGROUND

Diagnosis of spontaneous bacterial peritonitis in cirrhosis can be made when a patient has an ascites polymorphonuclear leukocyte count ≥250/mm3. However, symptomatic bacterascites, which is a variant of spontaneous bacterial peritonitis with signs of infection but an ascites polymorphonuclear leukocyte count <250/mm3, cannot be confirmed until the time-consuming ascites culture becomes positive. Currently, early indicators for symptomatic bacterascites remain undetermined.

AIMS

To develop a quick screening model for early detection of symptomatic bacterascites in cirrhosis.

MATERIALS AND METHODS

Data on patients with cirrhotic ascites from two hospitals (from 2010 to 2014) were collected retrospectively. Patients with symptomatic bacterascites were enrolled in the case group and compared with patients without any infection in the control group. Logistic regression analysis was used to build a model for screening symptomatic bacterascites, and a receiver operating characteristics curve was used to assess the model.

RESULTS

In total, 103 patients were enrolled in the case group and 204 patients were enrolled in the control group. A screening model was constructed based on body temperature, abdominal tenderness, blood neutrophil percentage, blood total bilirubin, prothrombin time, and ascites nucleated leukocyte count. The area under the receiver operating characteristic curve was 0.939; a screening score of 0.328 was the best cutoff value.

CONCLUSION

Patients with suspected symptomatic bacterascites can be quickly screened according to the developed model, and a screening score ≥0.328 indicates symptomatic bacterascites.

Infective endocarditis in patients with hepatic diseases

Few data have been published regarding the epidemiology and outcome of infective endocarditis (IE) in patients with chronic hepatic disease (CHD). A retrospective analysis of the Studio Endocarditi Italiano (SEI) database was performed to evaluate the epidemiology and outcome of CHD+ patients compared with CHD- patients. The diagnosis of IE was defined in accordance with the modified Duke criteria. Echocardiography, diagnosis, and treatment procedures were in accordance with current clinical practice. Among the 1722 observed episodes of IE, 300 (17.4 %) occurred in CHD+ patients. The cause of CHD mainly consisted of chronic viral infection. Staphylococcus aureus was the most common bacterial species in CHD+ patients; the frequency of other bacterial species (S. epidermidis, streptococci, and enterococci) were comparable among the two groups. The percentage of patients undergoing surgery for IE was 38.9 in CHD+ patients versus 43.7 in CHD- patients (p = 0.06). Complications were more common among CHD+ patients (77 % versus 65.3 %, p < 0.001); embolization (43.3 % versus 26.1 %, p < 0.001) and congestive heart failure (42 % versus 34.1 %, p = 0.01) were more frequent among CHD+ patients. Mortality was comparable (12.5 % in CHD- and 15 % in CHD+ patients). At multivariable analysis, factors associated with hospital-associated mortality were having an infection sustained by S. aureus, a prosthetic valve, diabetes and a neoplasia, and CHD. Being an intravenous drug user (IVDU) was a protective factor and was associated with a reduced death risk. CHD is a factor worsening the prognosis in patients with IE, in particular in patients for whom cardiac surgery was required.

The Negative Prognostic Impact of a First Ever Episode of Spontaneous Bacterial Peritonitis in Cirrhosis and Ascites

BACKGROUND

The prognostic impact of the first ever episode of spontaneous bacterial peritonitis (SBP) on patient outcomes is not well described. Our aim was to compare the clinical outcomes of cirrhotic patients with ascites, and with or without a first episode of SBP.

METHODS

Consecutive patients with cirrhosis and ascites were prospectively enrolled. Demographics, liver and renal function, and hemodynamics were documented at baseline, at resolution of SBP, and thereafter at 4 monthly intervals for 12 months. Complications of cirrhosis and survival were noted.

RESULTS

Twenty-nine cirrhotic patients with a first ever episode of SBP (group A) and 123 control patients slightly younger but similar in gender who never had SBP (group B) were enrolled. At SBP diagnosis, group A had worse liver and renal function (Model of End-Stage Liver Disease : 21.1±10.6 vs. 14.4±5.0), lower serum sodium concentrations, and a more hyperdynamic circulation compared with group B (all P<0.001). SBP resolution resulted in improvement in all measures to baseline levels. During follow-up, group A required more frequent hospital admissions than group B (58% vs. 43%), developed more cirrhotic complications, including further SBP (31% vs. 3%*), hyponatremia (12% vs. 0.8%*), acute kidney injury (50% vs. 23%*), hepatorenal syndrome type 1 (46% vs. 7%*), liver transplantation (62% vs. 30%*), and had a worse overall 1-year survival (38% vs. 70%*) (*P<0.05).

CONCLUSIONS

A first SBP episode is commonly followed by multiple complications, and overall worse prognosis. Consideration should be given to assess cirrhotic patients for liver transplant after the first episode of SBP.