High prevalence of antibiotic-resistant bacterial infections among patients with cirrhosis at a US liver center

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.

Unsolved Issues in the Treatment of Spontaneous Peritonitis in Patients with Cirrhosis: Nosocomial Versus Community-acquired Infections and the Role of Fungi

INTRODUCTION

Historically, spontaneous bacterial peritonitis (SBP) has represented one of the most frequent and relevant infectious complications of advanced liver disease, and this is still valid today. Nevertheless, in recent years the role of fungi as causative pathogens of primary peritonitis in patients with cirrhosis has become not negligible. Another issue is linked with the traditional distinction, instrumental in therapeutic choice, between community-acquired and nosocomial forms, according to the onset. Between these two categories, another one has been introduced: the so-called "healthcare-associated infections".

OBJECTIVE

To discuss the most controversial aspects in the management of SBP nowadays in the light of best available evidence.

METHODS

A review of recent literature through MEDLINE was performed.

RESULTS

The difference between community-acquired and nosocomial infections is crucial to guide empiric antibiotic therapy, since the site of acquisition impact on the likelihood of multidrug-resistant bacteria as causative agents. Therefore, third-generation cephalosporins cannot be considered the mainstay of treatment in each episode. Furthermore, the distinction between healthcare-associated and nosocomial form seems very subtle, especially in areas wherein antimicrobial resistance is widespread, warranting broad-spectrum antibiotic regimens for both. Finally, spontaneous fungal peritonitis is a not common but actually underestimated entity, linked to high mortality. Especially in patients with septic shock and/or failure of an aggressive antibiotic regimen, the empiric addition of an antifungal agent might be considered.

CONCLUSION

Spontaneous bacterial peritonitis is one of the most important complications in patients with cirrhosis. A proper empiric therapy is crucial to have a positive outcome. In this respect, a careful assessment of risk factors for multidrug-resistant pathogens is crucial. Likewise important, mostly in nosocomial cases, is not to overlook the probability of a fungal ascitic infection, namely a spontaneous fungal peritonitis.

Unresolved issues in the prophylaxis of bacterial infections in patients with cirrhosis

Bacterial infections are highly prevalent and a frequent cause of hospitalization and short-term mortality in patients with cirrhosis. Due to their negative impact on survival, antibiotic prophylaxis for bacterial infections in high-risk subgroups of patients with cirrhosis has been the standard of care for decades. Patients with prophylaxis indications include those at risk for a first episode of spontaneous bacterial peritonitis (SBP) due to a low ascitic fluid protein count and impaired liver and kidney function, patients with a prior episode of SBP and those with an episode of gastrointestinal bleeding. Only prophylaxis due to gastrointestinal bleeding has a known and short-time duration. All other indications imply long-lasting exposure to antibiotics - once the threshold requirement for initiating prophylaxis is met - without standardized criteria for re-assessing antibiotic interruption. Despite the fact that the benefit of antibiotic prophylaxis in reducing bacterial infections episodes and mortality has been thoroughly reported, the extended use of antibiotics in patients with cirrhosis has also had negative consequences, including the emergence of multi-drug resistant bacteria. Currently, it is not clear whether restricting the use of broad and fixed antibiotic regimens, tailoring the choice of antibiotics to local bacterial epidemiology or selecting non-antibiotic strategies will be the preferred antibiotic prophylaxis strategy for patients with cirrhosis in the future.

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.

Effects of Long-term Norfloxacin Therapy in Patients With Advanced Cirrhosis

BACKGROUND & AIMS

There is debate over the effects of long-term oral fluoroquinolone therapy in patients with advanced cirrhosis. We performed a randomized controlled trial to evaluate the effects of long-term treatment with the fluoroquinolone norfloxacin on survival of patients with cirrhosis.

METHODS

We performed a double-blind trial of 291 patients with Child-Pugh class C cirrhosis who had not received recent fluoroquinolone therapy. The study was performed at 18 clinical sites in France from April 2010 through November 2014. Patients were randomly assigned to groups given 400 mg norfloxacin (n = 144) or placebo (n = 147) once daily for 6 months. Patients were evaluated monthly for the first 6 months and at 9 months and 12 months thereafter. The primary outcome was 6-month mortality, estimated by the Kaplan-Meier method, censoring spontaneous bacterial peritonitis, liver transplantation, or loss during follow-up.

RESULTS

The Kaplan-Meier estimate for 6-month mortality was 14.8% for patients receiving norfloxacin and 19.7% for patients receiving placebo (P = .21). In competing risk analysis that took liver transplantation into account, the cumulative incidence of death at 6 months was significantly lower in the norfloxacin group than in the placebo group (subdistribution hazard ratio, 0.59; 95% confidence interval, 0.35-0.99). The subdistribution hazard ratio for death at 6 months with norfloxacin vs placebo was 0.35 (95% confidence interval, 0.13-0.93) in patients with ascites fluid protein concentrations <15 g/L and 1.39 (95% confidence interval, 0.42-4.57) in patients with ascites fluid protein concentrations ≥15 g/L. Norfloxacin significantly decreased the incidence of any and Gram-negative bacterial infections without increasing infections caused by Clostridium difficile or multiresistant bacteria.

CONCLUSIONS

In a randomized controlled trial of patients with advanced cirrhosis without recent fluoroquinolone therapy, norfloxacin did not reduce 6-month mortality, estimated by the Kaplan-Meier method. Norfloxacin, however, appears to increase survival of patients with low ascites fluid protein concentrations. ClinicalTrials.gov ID: NCT01037959.

Noninvasive screening identifies patients at risk for spontaneous bacterial peritonitis caused by multidrug-resistant organisms

Background and aims

Spontaneous bacterial peritonitis (SBP) is a severe complication of decompensated cirrhosis. The prevalence of multidrug-resistant organisms (MDROs) in patients with cirrhosis is increasing. Identification of patients at risk for SBP due to MDROs (ie, SBP with the evidence of MDROs or Stenotrophomonas maltophilia in ascitic culture, MDRO-SBP) is crucial to the early adaptation of antibiotic treatment in such patients. We therefore investigated whether MDROs found in ascitic cultures can also be found in specimens determined by noninvasive screening procedures.

Patients and methods

This retrospective study was conducted at the liver center of the University Hospital Frankfurt, Germany. Between 2011 and 2016, patients with cirrhosis were included upon diagnosis of SBP and sample collection of aerobic/anaerobic ascitic cultures. Furthermore, the performance of at least one complete MDRO screening was mandatory for study inclusion.

Results

Of 133 patients diagnosed with SBP, 75 (56.4%) had culture-positive SBP and 22 (16.5%) had MDRO-SBP. Multidrug-resistant Escherichia coli (10/22; 45.5%) and vancomycin-resistant enterococci (7/22; 36.4%) resembled the major causatives of MDRO-SBP. Rectal swabs identified MDROs in 17 of 22 patients (77.3%) who developed MDRO-SBP with a time-dependent sensitivity of 77% and 87% after 30 and 90 days upon testing, while negative predictive value was 83% and 76%, respectively. The majority of patients were included from intensive care unit or intermediate care unit.

Conclusion

MDRO screening may serve as a noninvasive diagnostic tool to identify patients at risk for MDRO-SBP. Patients with decompensated cirrhosis should be screened for MDROs from the first day of inpatient treatment onward.

Multidrug-resistant bacterial infections in cirrhotic patients: an epidemiological study

BACKGROUND

The purpose of this study is to describe the epidemiological features of bacterial infections caused by multidrug-resistant (MDR) bacteria in cirrhotic patients and their impact on mortality.

METHODS

A retrospective study of cirrhotic patients with culture-confirmed bacterial infections was performed between 2011 and 2017.

RESULTS

A total of 635 episodes in 563 patients with cirrhosis were included. Bacterial infections caused by MDR isolates accounted for 44.1% (280/635) of the episodes, nearly half of which were hospital acquired (48.4%). The most common MDR isolation site was the respiratory tract (36.4%, 102 episodes), followed by the abdominal cavity (35.4%, 99 episodes). Of the MDR isolates, carbapenem-resistant Enterobacteriaceae (CRE) (91 episodes) were the most common. Patients infected with MDR bacteria had significantly higher mortality than those not infected (25.1% vs 17.4%, p = 0.025). However, this increased mortality could be largely attributed to methicillin-resistant Staphylococcus aureus (MRSA). After adjustment for age, sex, and the model for end-stage liver disease (MELD) score, only MRSA infection was an independent risk factor for 28-day mortality in the multivariable Cox proportional hazard regression model analysis (HR, 2.964, 95% CI (1.175-7.478), p = 0.021).

CONCLUSIONS

MDR bacterial infections, especially CRE, have become frequent in patients with cirrhosis in recent years, with MRSA infections significantly increasing short-term mortality.

Infection and Predictors of Outcome of Cirrhotic Patients after Emergency Care Hospital Admission

INTRODUCTION AND AIMS

We aimed to explore the impact of infection diagnosed upon admission and of other clinical baseline parameters on mortality of cirrhotic patients with emergency admissions.

MATERIAL AND METHODS

We performed a prospective observational monocentric study in a tertiary care center. The association of clinical parameters and established scoring systems with short-term mortality up to 90 days was assessed by univariate and multivariable Cox regression analysis. Akaike's Information Criterion (AIC) was used for automated variable selection. Statistical interaction effects with infection were also taken into account.

RESULTS

218 patients were included. 71.2% were male, mean age was 61.1 ± 10.5 years. Mean MELD score was 16.2 ± 6.5, CLIF-consortium Acute on Chronic Liver Failure-score was 34 ± 11. At 28, 90 and 365 days, 9.6%, 26.0% and 40.6% of patients had died, respectively. In multivariable analysis, respiratory organ failure [Hazard Ratio (HR) = 0.15], albumin substitution (HR = 2.48), non-HCC-malignancy (HR = 4.93), CLIF-C-ACLF (HR = 1.10), HCC (HR = 3.70) and first episode of ascites (HR = 0.11) were significantly associated with 90-day mortality. Patients with infection had a significantly higher 90-day mortality (36.3 vs. 20.1%, p = 0.007). Cultures were positive in 32 patients with resistance to cephalosporins or quinolones in 10, to ampicillin/sulbactam in 14 and carbapenems in 6 patients.

CONCLUSION

Infection is common in cirrhotic ED admissions and increases mortality. The proportion of resistant microorganisms is high. The predictive capacity of established scoring systems in this setting was low to moderate.

Bacteremia in Patients With Liver Cirrhosis: Prevalence and Predictors of Multidrug Resistant Organisms

GOALS

The objective of this study was to assess the prevalence and predictors of multidrug resistant organisms (MDRO) in cirrhotic patients with bacteremia at a large tertiary center in the United States.

BACKGROUND

The epidemiology of bacteremia in patients with liver cirrhosis has not been well studied in the United States.

STUDY

This case-case control study included 180 adults with liver cirrhosis hospitalized from 2011 to 2015. Case group 1 were patients with bacteremia due to a MDRO (n=30). Case group 2 were patients with bacteremia due to a non-MDRO (n=60). Control group comprised patients without bacteremia (n=90). MDRO was defined as bacteria that was nonsusceptible to ≥1 agent in ≥3 antimicrobial categories.

RESULTS

Of the 90 bacteremia episodes, 44% were because of gram-positive bacteria, 50% were because of gram-negative bacteria, and 6% were polymicrobial. MDROs caused 30 of 90 (33%) bacteremia episodes, including methicillin-resistant Staphylococcus species [12% (11/90)], fluoroquinolone-resistant Enterobacteriaceae [10% (9/90)], and Enterococcus faecium [3% (3/90)]. Eight percent of Enterobacteriaceae produced extended-spectrum β-lactamases. Four independent predictors of MDROs were identified: nonwhite race [adjusted odds ratio (aOR), 3.35; 95% confidence interval (CI), 1.19-9.38], biliary cirrhosis (aOR, 11.75; 95% CI, 2.08-66.32), blood cultures obtained >48 hours after hospital admission (aOR, 6.02; 95% CI, 1.70-21.40), and recent health care exposure (aOR, 9.81; 95% CI, 2.15-44.88).

CONCLUSIONS

A significant proportion of bacteremia in cirrhotic patients was due to MDROs at a large US tertiary care center. Local epidemiology data and identification of risk factors associated with MDROs may help with optimal empiric antibiotic selection.

Prevalence and predictors of spontaneous bacterial peritonitis due to ceftriaxone-resistant organisms at a large tertiary centre in the USA

OBJECTIVES

The epidemiology of spontaneous bacterial peritonitis (SBP) due to ceftriaxone-resistant organisms has not been well studied in the USA. The primary objective of this study was to assess the prevalence and predictors of ceftriaxone-resistant SBP at a large US tertiary-care centre.

METHODS

This 1:1:4 case-case-control study included 141 adults with liver cirrhosis admitted from November 2011 to March 2016. Case group 1 were patients with SBP with a ceftriaxone-resistant organism (n=21). Case group 2 were patients with SBP with a ceftriaxone-susceptible organism (n=26). The control group were patients without SBP (n=94). Multiple logistic regression analysis was used to identify predictors of ceftriaxone-resistant SBP.

RESULTS

Fifty isolates were identified from 47 patients with culture-positive SBP (case groups 1 and 2). Of these 50 isolates, 32 (64%) were Gram-negatives [mostly Enterobacteriaceae (91%)], 15 (30%) were Gram-positives and 3 (6%) were Candida spp. The prevalence of ceftriaxone resistance in patients with culture-positive SBP was 45% (21/47). The most common ceftriaxone-resistant organisms were ESBL-producing Enterobacteriaceae (45%). Independent predictors of ceftriaxone-resistant SBP included duration of β-lactam therapy in the past 90days (aOR=1.07, 95% CI 1.01-1.13) and recent invasive gastrointestinal procedure (aOR=12.47, 95% CI 2.74-56.67).

CONCLUSIONS

The prevalence of ceftriaxone-resistant SBP was significant at a US tertiary centre. Local epidemiological data and identification of risk factors associated with ceftriaxone-resistant SBP, e.g. increased usage of previous β-lactam therapy and invasive gastrointestinal procedure, may help clinicians identify patients requiring alternative empirical antibiotics.

Rifaximin and Propranolol Combination Therapy Is More Effective than Propranolol Monotherapy for the Reduction of Portal Pressure: An Open Randomized Controlled Pilot Study

Background/Aims

Non-selective beta blockers (NSBBs) are currently the only accepted regimen for preventing portal hypertension (PHT)-related complications. However, the effect of NSBBs is insufficient in many cases. Bacterial translocation (BT) is one of the aggravating factors of PHT in cirrhosis; therefore, selective intestinal decontamination by rifaximin is a possible therapeutic option for improving PHT. We investigated whether the addition of rifaximin to propranolol therapy can improve hepatic venous pressure gradient (HVPG) response.

Methods

Sixty-four cirrhosis patients were randomly assigned to propranolol monotherapy (n=48) versus rifaximin and propranolol combination therapy (n=16). Baseline and post-treatment HVPG values, BT-related markers (lipopolysaccharide [LPS], LPS-binding protein [LBP], interleukin-6 [IL-6], and tumor necrosis factor α [TNF-α]), serological data, and adverse event data were collected. HVPG response rate was the primary endpoint.

Results

Combination therapy was associated with better HVPG response rates than monotherapy (56.2% vs 87.5%, p=0.034). In combination therapy, posttreatment BT-related markers were significantly decreased (LPS, p=0.005; LBP, p=0.005; IL-6, p=0.005; TNF-α, p=0.047).

Conclusions

Rifaximin combination therapy showed an additive effect in improving PHT compared to propranolol monotherapy. These pilot data suggest that the addition of rifaximin to NSBBs could be a good therapeutic option for overcoming the limited effectiveness of NSBBs.

IMPACT OF MICROBIOLOGICAL CHANGES ON SPONTANEOUS BACTERIAL PERITONITIS IN THREE DIFFERENT PERIODS OVER 17 YEARS

BACKGROUND

Spontaneous bacterial peritonitis is a serious complication in cirrhotic patients, and changes in the microbiological characteristics reported in the last years are impacting the choice of antibiotic used for treatment.

OBJECTIVE

The aim of the present study is to evaluate the changes in the epidemiology and bacterial resistance of the germs causing spontaneous bacterial peritonitis over three different periods over 17 years.

METHODS

All cirrhotic patients with spontaneous bacterial peritonitis and positive culture of ascites fluid were retrospectively studied in a reference Hospital in Southern Brazil. Three periods were ramdomly evaluated: 1997-1998, 2002-2003 and 2014-2015. The most frequent infecting organisms and the sensitivity in vitro to antibiotics were registered.

RESULTS

In the first period (1997-1998) there were 33 cases, the most common were: E. coli in 13 (36.11%), Staphylococcus coagulase-negative in 6 (16.66%), K. pneumoniae in 5 (13.88%), S. aureus in 4 (11.11%) and S. faecalis in 3 (8.33%). In the second period (2002-2003), there were 43 cases, the most frequent were: Staphylococus coagulase-negative in 16 (35.55%), S. aureus in 8 (17.77%), E. coli in 7 (15.55%) and K. pneumoniae in 3 (6.66%). In the third period (2014-2015) there were 58 cases (seven with two bacteria), the most frequent were: E. coli in 15 (23.1%), S. viridans in 12 (18.5%), K. pneumoniae in 10 (15.4%) and E. faecium 5 (7.7%). No one was using antibiotic prophylaxis. Considering all staphylococci, the prevalence increased to rates of the order of 50% in the second period, with a reduction in the third period evaluated. Likewise, the prevalence of resistant E. coli increased, reaching 14%.

CONCLUSION

There was a modification of the bacterial population causing spontaneous bacterial peritonitis, with high frequency of gram-positive organisms, as well as an increase in the resistance to the traditionally recommended antibiotics. This study suggests a probable imminent inclusion of a drug against gram-positive organisms in the empiric treatment of spontaneous bacterial peritonitis.

Prevalence and Impact of Bacterial Infections in Children With Liver Disease-A Prospective Study

BACKGROUND AND AIMS

Risk of infections is increased in patients with Acute Liver Failure (ALF) and Decompensated Chronic Liver Disease (DCLD). We evaluated the frequency, site, type and risk-factors for bacterial infections in children with ALF and DCLD and its effect on outcome.

METHODS

ALF or DCLD children were enrolled prospectively. Clinical and laboratory details were recorded. Cultures (blood, urine and ascites) and chest X-ray were done at admission followed by weekly surveillance cultures.

RESULTS

173 patients, 68 ALF and 105 DCLD were enrolled. Infections were more common in DCLD than ALF (60/105 [57.1%] vs. 27/68 [39.7%]; P = 0.02). Ascitic fluid infection, pneumonia, urinary tract infection and bacteremia were seen in 19%, 17.9%, 13.2% and 12.1% patients respectively. Healthcare-Associated (HCA) infections were most frequent (39/87, 44.8%), followed by Nosocomial (NC, 32%) and Community-Acquired (CA, 23%). Nearly 3/4th of bacterial isolates were resistant to cephalosporins and quinolones, 23% being Multiresistant Bacteria (MRB). DCLD patients with infection had higher Child-Pugh Score (10 [6-14] vs. 7 [6-14]; OR 3.2 [1.77-5.10]: P = 0.007), need for ICU care (26/60 vs. 3/45; OR 10.70 [2.98-38.42]: P = 0.01), in-hospital mortality (24/60 vs. 8/45;OR 3.08 [1.22-7.75]: P = 0.04) and mortality at 3 month follow-up (32/60 vs. 9/45; OR 4.57 [1.87-11.12]: P = 0.00). Infection did not affect the outcome in ALF.

CONCLUSION

Infections develop in 40% ALF and 57% DCLD children. HCA and NC infections account for 77% of infections. Most culture isolates are resistant to cephalosporins and fluoroquinolones and 23% have MRB. Risk of infections is higher in DCLD patients with advanced liver disease.

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.

Spontaneous bacterial and fungal peritonitis in patients with liver cirrhosis: A literature review

Spontaneous bacterial (SBP) and spontaneous fungal peritonitis (SFP) can be a life-threatening infection in patients with liver cirrhosis (LC) and ascites. One of the possible mechanisms of developing SBP is bacterial translocation. Although the number of polymorphonuclear cells in the culture of ascitic fluid is diagnostic for SBP, secondary bacterial peritonitis is necessary to exclude. The severity of underlying liver dysfunction is predictive of developing SBP; moreover, renal impairment and infections caused by multidrug-resistant (MDR) organism are associated with a fatal prognosis of SBP. SBP is treated by antimicrobials, but initial empirical treatment may not succeed because of the presence of MDR organisms, particularly in nosocomial infections. Antibiotic prophylaxis is recommended for patients with LC at a high risk of developing SBP, gastrointestinal bleeding, or a previous episode of SBP, but the increase in the risk of developing an infection caused by MDR organisms is a serious concern globally. Less is known about SFP in patients with LC, but the severity of underlying liver dysfunction may increase the hospital mortality. SFP mortality has been reported to be higher than that of SBP partially because the difficulty of early differentiation between SFP and SBP induces delayed antifungal therapy for SFP.

Infections complicating cirrhosis

Patients with cirrhosis have a high risk of bacterial infections. Bacterial infections induce systemic inflammation that may lead to organ failure and acute-on-chronic liver failure (ACLF) resulting in a high risk of short term mortality. The early diagnosis and treatment of bacterial infections is essential to improve the patient's prognosis. However, in recent years, the spread of multidrug resistant (MDR) bacterial infections has reduced the efficacy of commonly used antibiotics such as third generation cephalosporins. In patients at high risk of MDR bacteria, such as those with nosocomial infections, the early administration of broad spectrum antibiotics has been shown to improve the prognosis. However, early de-escalation of antibiotics is recommended to reduce a further increase in antibiotic resistance. Strategies to prevent acute kidney injury and other organ failures should be implemented. Although prophylaxis of bacterial infections with antibiotics improves the prognosis in selected patients, their use should be limited to patients at high risk of developing infections. In this article, we review the pathogenesis and management of bacterial infections in patients with cirrhosis.

Investigation on outcomes and bacterial distributions of liver cirrhosis patients with gram-negative bacterial bloodstream infection

Objective

The study aimed at analyzing the epidemiology and outcomes of liver cirrhosis patients undergoing gram-negative bacterial bloodstream infection.

Results

Totally 508 eligible patients were collected, with 25.79% 30-day mortality, and 58.86% patients were confirmed as nosocomial infection. The most common isolates were Escherichia coli (48.29%) and Klebsiella pneumoniae (19.29%), and multidrug-resistant isolates accounted for 36.61%. The bacterial distributions were similar between survivors and non-survivors (P>0.05), but showed close association with acquisition sites of infection (P<0.05). Nosocomial infection (HR=1.589, 95% CI=1.004-2.517), Child-Pugh grade (HR=2.471, 95% CI=1.279-4.772), septic shock (HR=1.966, 95% CI=1.228-3.146), complications (HR=3.529, 95% CI=2.140-5.818), and WBC (HR=1.065, 95% CI=1.018-1.114) were independent indicators for 30-day mortality. β-lactamase inhibitor antibiotics exerted a high antibacterial activity.

Methods

The inpatients with liver cirrhosis developed gram-negative bacterial bloodstream infection were collected. The clinical characteristics, bacterial distribution and drug sensitivity results of patients were compared according to their 30-day survival status and acquisition sites of infections. Cox regression model was applied to evaluate the risk factors for 30-day mortality.

Conclusion

Escherichia coli and Klebsiella pneumoniae are frequently isolated from gram-negative bacterial bloodstream infection episodes in cirrhosis patients. Acquisition site of infection can influence clinical characteristics and etiological distribution. β-lactamase inhibitor antibiotics may be the first choice for empirical treatments.

Spontaneous bacteremia and spontaneous bacterial peritonitis share similar prognosis in patients with cirrhosis: a cohort study

BACKGROUND AND AIMS

Spontaneous bacteremia is a poorly characterized infection in patients with cirrhosis. We compared the incidence of mortality and acute kidney injury in patients with spontaneous bacterial peritonitis and spontaneous bacteremia, and identified risk factors for mortality and acute kidney injury in patients with spontaneous bacteremia.

METHODS

We performed a retrospective cohort study of patients with cirrhosis and spontaneous bacteremia or spontaneous bacterial peritonitis from 2008 to 2016 at Hospital Italiano, Buenos Aires. We compared the cumulative incidence of acute kidney injury and death between the two infections, and identified risk factors for these outcomes in patients with spontaneous bacteremia.

RESULTS

Seventy-one patients with spontaneous bacteremia and 55 patients with spontaneous bacterial peritonitis were included. Most infections were nosocomial. Overall, 26% of bacteria were resistant and 11% multi-resistant. We found no significant association between acute kidney injury [subhazard ratio (sHR) 1.05 (95% confidence interval, CI 0.67-1.63, p = 0.83)] or death [sHR 1.15 (95% CI 0.60-2.20, p = 0.68)] and type of spontaneous infection in multivariate analyses adjusting for basal Model for End-Stage Liver Disease (MELD) score. In patients with spontaneous bacteremia, baseline MELD score was independently associated with acute kidney injury [sHR 1.07 (95% CI 1.03-1.11, p = 0.001)] and death [sHR 1.07 (95% CI 1.02-1.15, p = 0.03)].

CONCLUSIONS

Short-term acute kidney injury and mortality rates were similar in patients with spontaneous bacteremia and spontaneous bacterial peritonitis. Risk assessment of patients with spontaneous bacteremia can be performed with baseline MELD score.

An Insight into Antibiotic Resistance to Bacterial Infection in Chronic Liver Disease

BACKGROUND

End stage liver disease leads to immune dysfunction which predisposes to infection. There has been a rise in antibiotic resistant infections in these patients. There is scanty data f from India or idea regarding the same.

AIM OF THE STUDY

The present study was undertaken to determine the type of infection acquired and the prevalence of antibiotic resistant infections in cirrhotic patients at a tertiary referral center in South India.

MATERIALS AND METHODS

In this retrospective study, all consecutive cirrhotic patients hospitalized between 2011 and 2013 with a microbiologically-documented infection were enrolled. Details of previous admission and antibiotics if received were noted. In culture positive infections, the source of infection (ascites, skin, respiratory tract: sputum/endotracheal tube aspirate, pleural fluid; urine and blood) and microorganisms isolated and their antibiotic susceptibility was noted.

RESULTS

A total of 92 patients had 240 culture positive samples in the study period. Majority were Klebseilla followed by Escherichia coli and Enterococcus in nosocomial and health care associated infections. However, Enteroccocus was followed by E. coli and Klebsiella in community acquired infections. The antibiotic sensitivity pattern was analyzed for the major causative organisms such as E. coli, Klebsiella and Enterococcus. Most common resistant strains were extended spectrum beta lactamase producing enterobacteriacae (ESBL) followed by carbapenemase producing Klebsiella and methicillin resistant Staphylococcus aureus.

CONCLUSION

Noscomial infection is the most common type, with Klebsiella and E. coli and there is significant rise in ESBL producing organism.

Microbiology and antibiotic susceptibility patterns in spontaneous bacterial peritonitis: A study of two Dutch cohorts at a 10-year interval

Background

Recent investigations suggest an increasing prevalence of Gram-positive and antibiotic-resistant bacteria causing spontaneous bacterial peritonitis (SBP), probably related to changes in antibiotic prescription patterns, in particular more widespread and long-term use of antibiotic prophylaxis with quinolones.

Objective

The primary objective of this study was to assess potential changes in the microbiology of SBP in two patient cohorts studied at a 10-year interval. Further aims were to study prognostic factors and outcome of SBP.

Methods

A retrospective double-cohort study, including all ascitic cultures from patients with cirrhosis obtained 2003–2005 and 2013–2014, was conducted.

Results

In total 312 patients were included, 125 patients in the first and 187 patients in the second cohort. SBP was diagnosed in 132 of 840 analyzed ascitic fluid samples; 62 samples were culture positive. An increase of Gram-positive bacterial isolates was noted from 26% to 46% between cohorts (p = 0.122). The prevalence of multidrug-antibiotic–resistant pathogens increased from 25% to 32% (p = 0.350). Survival after SBP among the two cohorts was comparable.

Conclusion

This single-center study in the Netherlands found a modest but nonsignificant increase in the proportion of patients with SBP caused by Gram-positive bacteria and multidrug-antibiotic–resistant bacteria over a 10-year period. Our findings differ from reported data in other countries and suggest empiric antibiotic prophylaxis and treatment of SBP should be based on national and regional microbiological findings and resistance patterns.

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.

The impact of carbapenem resistance on clinical deterioration and mortality in patients with liver disease

BACKGROUND & AIMS

Infections with multidrug-resistant gram-negative bacteria are significantly impairing the prognosis of patients with liver disease. In particular, carbapenem resistance further narrows therapeutic options. This study investigates the impact of carbapenem-resistant gram-negative bacteria on the outcome of patients with liver disease and cirrhosis.

METHODS

Between January 2011 and July 2015, 132 patients treated at the tertiary liver transplant centre at University Hospital Frankfurt, Germany, were tested positive for carbapenem-resistant gram-negative bacteria and retrospectively analysed in this study. Risk factors for fatal outcome were evaluated using multivariate regression analysis. Competing-risk analysis was performed on patients tested positive for Enterobacteriaceae or non-fermenting species, for example, Pseudomonas aeruginosa, Acinetobacter baumannii, Stenotrophomonas maltophilia. Subgroup analysis of cirrhotic patients was performed on a matched cohort of cirrhotic patients, comparable model for end-stage liver disease and tested negative for carbapenem-resistant gram-negative bacteria.

RESULTS

97 (73.5%) and 35 (26.5%) patients were infected or colonised with carbapenem-resistant gram-negative bacteria respectively. Within the observation period, 61/132 (46.2%) patients died, with sepsis being the leading cause (38/61, 62.3%). Decompensated liver disease, sepsis and admission to intensive care unit were independent risk factors for fatal outcome. Lethal sepsis in patients positive for non-fermenting bacteria was significantly more frequent than in those positive for Enterobacteriaceae, independently from liver function. Subgroup analysis of cirrhotic patients showed that sepsis (54.9% vs 13%) and lethal sepsis were significantly more frequent after detection of carbapenem-resistant gram-negative bacteria, independently from localisation of pathogen detection.

CONCLUSIONS

Patients with advanced liver disease are prone to fatal infections caused by carbapenem-resistant gram-negative bacteria.

Bacterial distributions and prognosis of bloodstream infections in patients with liver cirrhosis

Bloodstream infections (BSIs) are a frequently observed complication in liver cirrhosis patients. This study aimed to investigate the microbiological characteristics and outcomes of BSIs in patients with liver cirrhosis. We retrospectively studied 852 patients with liver cirrhosis who developed a BSI. Patient outcome was evaluated using 30-day mortality and assessed using multivariate stepwise logistic regression analysis. Antibiotic sensitivity of the pathogens was tested. Gram-negative bacteria were responsible for 59.6% of BSIs, and Gram-positive bacteria caused 40.4% of the episodes among liver cirrhosis patients. The bacterial distribution significantly differed between hospital-acquired and community-acquired infections, especially in cases caused by Gram-negative pathogens. The results of the drug sensitivity test suggested that amikacin, cefoperazone/sulbactam, and piperacillin/tazobactam highly suppressed Gram-negative infections, while vancomycin and teicoplanin strongly inhibited Gram-positive BSIs. Liver failure, liver cancer, complications, Child-Pugh grade, septic shock, administration of appropriate antibiotics within 24 h, ICU admission, nosocomial infection, and Gram nature of the bacteria were independent risk factors for 30-day mortality (P < 0.05). The choice of initial empirical antibiotics should be based on the type, severity and origin of infection and on the local epidemiological data on antibiotic resistance. Accurate evaluation of risk factors for mortality may improve appropriate therapeutic choice.

The gut microbiome and liver cancer: mechanisms and clinical translation

Hepatocellular carcinoma (HCC) is the third leading cause of worldwide cancer mortality. HCC almost exclusively develops in patients with chronic liver disease, driven by a vicious cycle of liver injury, inflammation and regeneration that typically spans decades. Increasing evidence points towards a key role of the bacterial microbiome in promoting the progression of liver disease and the development of HCC. Here, we will review mechanisms by which the gut microbiota promotes hepatocarcinogenesis, focusing on the leaky gut, bacterial dysbiosis, microbe-associated molecular patterns and bacterial metabolites as key pathways that drive cancer-promoting liver inflammation, fibrosis and genotoxicity. On the basis of accumulating evidence from preclinical studies, we propose the intestinal-microbiota-liver axis as a promising target for the simultaneous prevention of chronic liver disease progression and HCC development in patients with advanced liver disease. We will review in detail therapeutic modalities and discuss clinical settings in which targeting the gut-microbiota-liver axis for the prevention of disease progression and HCC development seems promising.

Bacterial infections in acute variceal hemorrhage despite antibiotics-a multicenter study of predictors and clinical impact

Background and aims

Current guidelines recommend antibiotic prophylaxis in all patients presenting with cirrhosis and acute variceal hemorrhage (AVH). We aimed to evaluate the characteristics and clinical impact of "early" infections (developing within 14 days) of AVH in a real-world setting.

Methods

We analyzed retrospective data from a cohort of 371 adult patients with cirrhosis and AVH all of whom had received antibiotic prophylaxis (74% men; mean age 56 years), admitted to tertiary care hospitals in Edmonton, Alberta, Canada, and Barcelona, Spain. Sensitivity analyses were presented for culture-positive (confirmed) infections.

Results

The mean MELD was 16. Fifty-two percent of patients received quinolones, 45% third-generation cephalosporins and 3% other antibiotics. Fourteen percent (51/371) developed an infection within 14 days of AVH. Seventy-five percent of infections were culture positive and occurred at a mean of six days from AVH. When all infections were considered, respiratory infections were the most common (53%) followed by urinary tract infections (17%) and bacteremia (16%). Resistance patterns differed between countries. Outpatient antibiotic prophylaxis (OR 5.4) and intubation (OR 2.6) were independent predictors of bacterial infection. Bacterial infection (OR 2.6) and the MELD (OR 1.2) were independent predictors of six-week mortality.

Conclusions

Early bacterial infections develop in 14% of cirrhotic patients with AVH despite antibiotic prophylaxis, and have a negative impact on six-week mortality. Intubation and outpatient antibiotic prophylaxis are associated with increased risk of early bacterial infections. Patients at risk should be followed closely with prompt infection workup and local antibiogram-based expansion of antibiotic therapy in case of clinical decline.

Antibiotic resistance in healthcare-related and nosocomial spontaneous bacterial peritonitis

BACKGROUND

Spontaneous bacterial peritonitis (SBP) can be life threatening in patients with liver cirrhosis. In contrast to community-acquired SBP, no standard treatment has been established for healthcare-related and nosocomial SBP.

MATERIALS AND METHODS

We prospectively collected healthcare-related and nosocomial SBP cases from March 2012 till February 2016 at the Department of Internal Medicine I of the University of Bonn and analysed the prevalence of antibiotic resistance among the isolated bacteria. SBP was diagnosed according to international guidelines. Ciprofloxacin, ceftriaxone and meropenem were used as reference substance for resistance to quinolones, third-generation cephalosporins and carbapenems, respectively.

RESULTS

Ninety-two SBP episodes in 86 patients were identified: 63 episodes (69%) were nosocomial. Escherichia coli, Klebsiella species, enterococci and streptococci were most frequently isolated. Frequencies of these microorganisms were comparable for healthcare-related and nosocomial SBP (14% vs. 11%, 14% vs. 8%, 14% vs. 5% and 10% vs. 6%, respectively). In general, antibiotic resistance was higher in isolates from nosocomial than from healthcare-related SBP (50% vs. 18% for quinolones, 30% vs. 11% for piperacillin-tazobactam; P > 0·05), but comparable concerning third-generation cephalosporins (30% vs. 33%). All microorganisms were sensitive to carbapenems apart from nosocomial infections with Enterococcus faecium (n = 3) and Candida albicans (n = 1) due to intrinsic resistance or lack of microbiological efficacy, respectively. No multidrug-resistant microorganisms were detected. Resistance to initial antibiotic treatment affected 30-day survival negatively (18% vs. 68%; P = 0·002).

CONCLUSION

Resistance to initial antibiotic treatment was associated with increased mortality. With resistance to cephalosporins being frequent, piperacillin-tazobactam or carbapenems might be preferred as treatment of SBP.

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.

New antibiotic strategies in patients with cirrhosis and bacterial infection

Early diagnosis and adequate empirical antibiotic treatment of bacterial infections in advanced cirrhosis is essential to improve outcomes given the high risk of developing severe sepsis, multiple organ failure and death. β-lactams and quinolones are nowadays frequently ineffective in nosocomial and healthcare associated infections, due to the increasing prevalence of multidrug resistant (MDR) bacteria reported across different geographical areas. Recent antibiotic exposure also increases the risk of developing MDR bacterial infections. Initial antibiotic strategies should therefore be tailored according to the presence or absence of risk factors of MDR bacteria and to the severity of infection and should consider the local epidemiology. Empirical treatment in the population at high risk of MDR bacterial infections requires the use of broad-spectrum antibiotics (carbapenems or tigecycline) and of drugs active against specific resistant bacteria (glycopeptides, linezolid, daptomycin, amikacin, colistin). Early de-escalation policies are recommended to prevent the spread of MDR bacteria in cirrhosis.

Antibiotic prophylaxis in cirrhosis: Good and bad

Patients with cirrhosis, particularly those with decompensated cirrhosis, are at increased risk of bacterial infections that may further precipitate other liver decompensations including acute-on-chronic liver failure. Infections constitute the main cause of death in patients with advanced cirrhosis, and strategies to prevent them are essential. The main current strategy is the use of prophylactic antibiotics targeted at specific subpopulations at high risk of infection: prior episode of spontaneous bacterial peritonitis, upper gastrointestinal bleeding, and low-protein ascites with associated poor liver function. Antibiotic prophylaxis effectively prevents not only the development of bacterial infections in all these indications but also further decompensation (variceal bleeding, hepatorenal syndrome) and improves survival. However, antibiotic prophylaxis is also associated with a clinically relevant and increasing drawback, the development of infections due to multidrug-resistant organisms. Several strategies have been suggested to balance the risks and benefits of antibiotic prophylaxis.

CONCLUSION

Antibiotic stewardship principles such as the restriction of antibiotic prophylaxis to subpopulations at a very high risk for infection, the avoidance of antibiotic overuse, and early deescalation policies are key to achieve this balance; nonantibiotic prophylactic measures such as probiotics, prokinetics, bile acids, statins, and hematopoietic growth factors could also contribute to ameliorate the development and spread of multidrug-resistant bacteria in cirrhosis. (Hepatology 2016;63:2019-2031).

PREVALENCE OF BACTERIAL RESISTANCE IN HOSPITALIZED CIRRHOTIC PATIENTS IN SOUTHERN BRAZIL: A NEW CHALLENGE

BACKGROUND & AIMS

An increased frequency of infections by multiresistant bacteria has been described in hospitalized patients. The aim of this study was to evaluate the bacterial resistance profile in cirrhotic patients.

METHODS

This is a retrospective observational study. We assessed the antimicrobial susceptibility of 5,839 bacterial isolates from patients with and without cirrhosis. Regarding the multidrug resistance, we evaluated 4,505 bacterial isolates from 2,180 patients.

RESULTS

Two hundred and fifty-one patients had cirrhosis (mean age 57.6 ± 11 years; 61.8% were male, 47.8% of cases associated with hepatitis C virus). Of the isolates of patients with and without cirrhosis, 174/464 (37.5%) and 1,783/4,041 (44.1%) were multiresistant, respectively (p = 0.007). E. coli was the most common multiresistant bacteria in both groups. Approximately 20% of E. coli and Klebsiella sp. isolates were ESBL-producers and 44% of S. aureus isolates were methicillin-resistant in cirrhotic patients. In cirrhotic patients admitted to the emergency department, hospital ward, and intensive care unit, 28.3%, 50% and 40% had multiresistant isolates, respectively. In patients with and without cirrhosis, 36.2% and 33.5% of isolates were resistant to third-generation cephalosporins, respectively.

CONCLUSIONS

The empirical treatment of infections in hospitalized patients using broad-spectrum antibiotics should consider the observed pattern of bacterial resistance.

Rifaximin for the treatment of irritable bowel syndrome - a drug safety evaluation

INTRODUCTION

Irritable bowel syndrome is a functional gastrointestinal disorder with a multifactorial etiology. Alterations of intestinal motility and immunity, gut-brain interactions, as well as gut microbiota dysbiosis contribute to the development of irritable bowel syndrome. Therefore, gut microbiota modulation by non-absorbable antibiotics is a therapeutic option in patients with IBS.

AREAS COVERED

Published articles including patients with irritable bowel syndrome reporting data about rifaximin activity and safety have been searched throughout the literature and selected.

EXPERT OPINION

The optimal antibiotic molecule should be local-acting, long-acting and safe-acting. Rifaximin is a non-absorbable antibiotic with additional anti-inflammatory and gut microbiota-modulating activity. It is effective in inducing symptoms relief in patients with IBS, even after repeated treatment courses. Rifaximin-related side effects in patients with IBS are reported to be mild and infrequent; microbial resistance is rare and transient, due to the high local concentration of the drug and to the absence of horizontal transmission. Clostridium difficile infection is not usual in patients receiving rifaximin in absence of predisposing conditions such as hospitalization and immunosuppression, which are uncommon in patients affected by irritable bowel syndrome. Nevertheless rifaximin is an antibiotic active against Clostridium difficile infection. Rifaximin has limited metabolic interactions and is not expected to interfere with drug metabolism in patients with normal hepatic function. These properties make rifaximin a safe antibiotic for gut microbiota modulation in patients with IBS.

Extensively drug-resistant bacteria are an independent predictive factor of mortality in 130 patients with spontaneous bacterial peritonitis or spontaneous bacteremia

AIM: To evaluate the epidemiology and outcomes of culture-positive spontaneous bacterial peritonitis (SBP) and spontaneous bacteremia (SB) in decompensated cirrhosis.

METHODS: We prospectively collected clinical, laboratory characteristics, type of administered antibiotic, susceptibility and resistance of bacteria to antibiotics in one hundred thirty cases (68.5% males) with positive ascitic fluid and/or blood cultures during the period from January 1, 2012 to May 30, 2014. All patients with SBP had polymorphonuclear cell count in ascitic fluid > 250/mm³. In patients with SB a thorough study did not reveal any other cause of bacteremia. The patients were followed-up for a 30-d period following diagnosis of the infection. The final outcome of the patients was recorded in the end of follow-up and comparison among 3 groups of patients according to the pattern of drug resistance was performed.

RESULTS: Gram-positive-cocci (GPC) were found in half of the cases. The most prevalent organisms in a descending order were Escherichia coli (33), Enterococcus spp (30), Streptococcus spp (25), Klebsiella pneumonia (16), S. aureus (8), Pseudomanas aeruginosa (5), other Gram-negative-bacteria (GNB) (11) and anaerobes (2). Overall, 20.8% of isolates were multidrug-resistant (MDR) and 10% extensively drug-resistant (XDR). Health-care-associated (HCA) and/or nosocomial infections were present in 100% of MDR/XDR and in 65.5% of non-DR cases. Meropenem was the empirically prescribed antibiotic in HCA/nosocomial infections showing a drug-resistance rate of 30.7% while third generation cephalosporins of 43.8%. Meropenem was ineffective on both XDR bacteria and Enterococcus faecium (E. faecium). All but one XDR were susceptible to colistin while all GPC (including E. faecium) and the 86% of GNB to tigecycline. Overall 30-d mortality was 37.7% (69.2% for XDR and 34.2% for the rest of the patients) (log rank, P = 0.015). In multivariate analysis, factors adversely affecting outcome included XDR infection (HR = 2.263, 95%CI: 1.005-5.095, P = 0.049), creatinine (HR = 1.125, 95%CI: 1.024-1.236, P = 0.015) and INR (HR =1.553, 95%CI: 1.106-2.180, P = 0.011).

CONCLUSION: XDR bacteria are an independent life-threatening factor in SBP/SB. Strategies aiming at restricting antibiotic overuse and rapid identification of the responsible bacteria could help improve survival.

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.

Epidemiology of bacterial infections in patients with liver cirrhosis. Experience in a Spanish tertiary health center

INTRODUCTION

Bacterial infections represent a serious complication of liver cirrhosis. Traditionally, Gram negative bacteria have been described as the microorganisms responsible for the majority of the infections. However, in the past few years, changes in the microbiological spectrum have been described, and multiresistant bacteria are observed more frequently. 

OBJECTIVE

To assess the proportion of patients with infections caused by multiresistant bacteria admitted to our hospital, and to obtain information about their epidemiology, risk factors and clinical impact. 

MATERIALS AND METHODS

We performed a retrospective evaluation of 294 cirrhotic patients admitted to our unit due to infection between June, 2011, and June, 2013. 

RESULTS

We isolated 310 microorganisms from 294 patients; 109 (35.2%) were Gram positive, 167 (53.9%), Gram negative, and 34, fungi (11%). As for the microbiological agents, the most frequent was Escherichia coli (98 isolations). The infection was community-acquired in 22.9% of cases, healthcareassociated in 38.1% and nosocomial in 39%. Worse liver infections and septic shock were more frequent among patients with multiresistant isolates (p=0.05); and intrahospital mortality was also higher among them (p=0.017). Previous hospital admission, antibiotic treatment 60 days before, nosocomial or healthcare-associated acquisition and bacterial isolation in control cultures were identified as possible risk factors for the development of multiresistant infection. 

DISCUSSION

The results of our study confirm that important changes have ocurred in the microbiological spectrum of bacterial infections in patients with liver cirrhosis. Multiresistant bacteria are associated with high morbidity and mortality, as well as failure of traditional antibiotic treatment. Successfull control of the infection requires an early identification of patients at risk.

Novel prevention strategies for bacterial infections in cirrhosis

INTRODUCTION

Bacterial infections are a serious complication of cirrhosis, as they can lead to decompensation, multiple organ failure, and/or death. Preventing infections is therefore very relevant. Because gut bacterial translocation is their main pathogenic mechanism, prevention of infections is mostly based on the use of orally administered poorly absorbed antibiotics such as norfloxacin (selective intestinal decontamination). However, antibiotic prophylaxis leads to antibiotic resistance, limiting therapy and increasing morbidity and mortality. Prevention of bacterial infections in cirrhosis should therefore move away from antibiotics.

AREAS COVERED

This review focuses on various potentially novel methods to prevent infections in cirrhosis focusing on non-antibiotic strategies. The use of probiotics, nonselective intestinal decontamination with rifaximin, prokinetics and beta-blockers or fecal microbiota transplant as means of targeting altered gut microbiota, bile acids and FXR agonists are all potential alternatives to selective intestinal decontamination. Prokinetics and beta-blockers can improve intestinal motility, while bile acids and FXR agonists help by improving the intestinal barrier. Finally, granulocyte colony stimulating factor (G-CSF) and statins are emerging therapeutic strategies that may improve immune dysfunction in cirrhosis.

EXPERT OPINION

Evidence for these strategies has been restricted to animal studies and proof-of concept studies but we expect this to change in coming years.

Management of uninfected and infected ascites in cirrhosis

Ascites is the most frequent complication of patients with cirrhosis. Ascites is related to increased renal sodium retention as a result of increased activity of the renin-angiotensin-aldosterone system in response to marked vasodilation of the splanchnic circulation. Management of uncomplicated ascites is based on a low-sodium diet and diuretics. However, approximately 10% of patients develop refractory ascites during follow-up, which is associated with a poor prognosis. The treatment of choice in patients with refractory ascites is large-volume paracentesis associated with intravenous albumin. Moreover, patients who develop refractory ascites should be considered as candidates for liver transplantation. Patients with ascites are all at risk of developing spontaneous bacterial peritonitis (SBP). SBP is a common infection in patients with cirrhosis with a risk of mortality of 20%. Empirical antibiotics are the treatment of choice in patients with SBP but differ depending on the acquisition site of infection, because nosocomial infections have a higher risk of being caused by multiresistant bacteria. In addition to antibiotic treatment, all patients with SBP should also receive intravenous albumin. This review summarizes the management of uninfected ascites and SBP in cirrhosis.

Effect of rifaximin on gut microbiota composition in advanced liver disease and its complications

Liver cirrhosis is a paradigm of intestinal dysbiosis. The qualitative and quantitative derangement of intestinal microbial community reported in cirrhotic patients seems to be strictly related with the impairment of liver function. A kind of gut microbial “fingerprint”, characterized by the reduced ratio of “good” to “potentially pathogenic” bacteria has recently been outlined, and is associated with the increase in Model for End-Stage Liver Disease and Child Pugh scores. Moreover, in patients presenting with cirrhosis complications such as spontaneous bacterial peritonitis (SBP), hepatic encephalopathy (HE), and, portal hypertension intestinal microbiota modifications or the isolation of bacteria deriving from the gut are commonly reported. Rifaximin is a non-absorbable antibiotic used in the management of several gastrointestinal diseases. Beyond bactericidal/bacteriostatic, immune-modulating and anti-inflammatory activity, a little is known about its interaction with gut microbial environment. Rifaximin has been demonstrated to exert beneficial effects on cognitive function in patients with HE, and also to prevent the development of SBP, to reduce endotoxemia and to improve hemodynamics in cirrhotics. These results are linked to a shift in gut microbes functionality, triggering the production of favorable metabolites. The low incidence of drug-related adverse events due to the small amount of circulating drug makes rifaximin a relatively safe antibiotic for the modulation of gut microbiota in advanced liver disease.

Immunomodulating effects of antibiotics used in the prophylaxis of bacterial infections in advanced cirrhosis

The use of norfloxacin either as primary or secondary prophylaxis of bacterial infections in advanced cirrhosis has improved patient’s survival. This may be explained not only due to a significant decrease in the number of infections, but also because of a direct immunomodulatory effect. Selective intestinal decontamination with norfloxacin reduces translocation of either viable bacteria or bacteria-driven products from the intestinal lumen. In addition, norfloxacin directly modulates the systemic inflammatory response. The pro-inflammatory cytokine profile secreted by neutrophils from these patients shows a close, significant, and inverse correlation with serum norfloxacin levels. Similar effects have been described with other quinolones in different clinical conditions. Although the underlying mechanisms are not well defined for most of the antibiotics, the pathways triggered for norfloxacin to induce such immunomodulatory effects involve the down-regulation of pro-inflammatory inducible nitric oxide synthase, cyclooxygenase-2, and NF-κB and the up-regulation of heme-oxygenase 1 and IL-10 expression. The knowledge of these immunomodulatory effects, additional to their bactericidal role, improves our comprehension of the interaction between antibiotics and the cellular host response and offer new possibilities for the development of new therapeutic strategies to manage and prevent bacterial infections in cirrhosis.

Pathogen profile and drug resistance analysis of spontaneous peritonitis in cirrhotic patients

AIM: To investigate the microbiological characteristics and drug resistance in liver cirrhosis patients with spontaneous peritonitis.

METHODS: We analyzed the data of patients with liver cirrhosis and abdominal infection at the First Affiliated Hospital of Zhejiang University between January 2011 and December 2013. Pathogens present in the ascites were identified, and their sensitivity to various antibiotics was determined.

RESULTS: We isolated 306 pathogenic bacteria from 288 cases: In 178 cases, the infection was caused by gram-negative strains (58.2%); in 85 cases, gram-positive strains (27.8%); in 9 cases, fungi (2.9%); and in 16 cases, more than one pathogen. The main pathogens were Escherichia coli (E. coli) (24.2%), Klebsiella pneumoniae (18.9%), Enterococcus spp. (11.1%), and Staphylococcus aureus (7.5%). Of the 306 isolated pathogens, 99 caused nosocomial infections and 207 caused community-acquired and other infections. The E. coli and K. pneumoniae strains produced more extended-spectrum β-lactamases in cases of nosocomial infections than non-nosocomial infections (62.5% vs 38%, P < 0.013; 36.8% vs 12.8%, P < 0.034, respectively). The sensitivity to individual antibiotics differed between nosocomial and non-nosocomial infections: Piperacillin/tazobactam was significantly more effective against non-nosocomial E. coli infections (4% vs 20.8%, P < 0.021). Nitrofurantoin had stronger antibacterial activity against Enterococcus species causing non-nosocomial infections (36.4% vs 86.3%, P < 0.009).

CONCLUSION: The majority of pathogens that cause abdominal infection in patients with liver cirrhosis are gram-negative, and drug resistance is significantly higher in nosocomial infections than in non-nosocomial infections.

Bacterial infections in alcoholic and nonalcoholic liver cirrhosis

OBJECTIVES

Longitudinal, population-based data on the occurrence, localization, and severity of bacterial infections over time in patients with alcoholic compared with nonalcoholic cirrhosis are limited.

MATERIALS AND METHODS

All patients with incident cirrhosis diagnosed in 2001-2010 (area of 600,000 inhabitants) were retrospectively identified. All bacterial infections resulting in or occurring during an inpatient hospital episode during this period were registered. The etiology of cirrhosis (alcoholic vs. nonalcoholic), infection localization, and outcome as well as bacterial resistance patterns were analyzed. Patients were followed until death, transplant, or the end of 2011.

RESULTS

In all, 633 cirrhotics (363 alcoholic, 270 nonalcoholic) experienced a total of 398 infections (2276 patient-years). Among patients diagnosed with cirrhosis each year from 2001 to 2010, increasing trends were noted in the occurrence of infection (from 13 to 27%, P<0.001) and infection-related in-hospital mortality (from 2 to 7%, P=0.05), the latter mainly in the alcoholic group. Although alcoholic etiology was related to the occurrence of more frequent infection (Kaplan-Meier, P<0.001), this relationship was not significant after adjustment for confounders in Cox regression analysis (P=0.056). Resistance to piperacilin-tazobactam and carbapenems was more common in infections occurring in alcoholic versus nonalcoholic cirrhosis (13 vs. 5%, P=0.057 and 12 vs. 2%, P=0.009). Alcoholic etiology predicted pneumonia and infections caused by Gram-positive bacteria in multivariate analysis (P<0.05 for both).

CONCLUSION

In a population-based cirrhotic cohort, bacterial infections increased over time, which, in the case of alcoholic cirrhosis, was associated with pneumonia and bacterial resistance to antibiotics. However, alcoholic etiology was not related indepedently to the occurrence of bacterial infections.

Risk of Bacterial Infection in Patients With Cirrhosis and Acute Variceal Hemorrhage, Based on Child-Pugh Class, and Effects of Antibiotics

BACKGROUND & AIMS

Antibiotics frequently are overused and are associated with serious adverse events in patients with cirrhosis. However, these drugs are recommended for all patients presenting with acute variceal hemorrhage (AVH). We investigated whether patients should be stratified for antibiotic prophylaxis based on Child-Pugh scores, to estimate risks of bacterial infection, rebleeding, and mortality, and whether antibiotics have equal effects on patients of all Child-Pugh classes. We performed a sensitivity analysis using model for end-stage liver disease (MELD) scores.

METHODS

In a retrospective study, we analyzed data from 381 adult patients with cirrhosis and AVH (70% men; mean age, 56 y), admitted from 2000 through 2009 to 2 tertiary care hospitals in Edmonton, Alberta, Canada. We excluded patients with bacterial infection on the day of AVH. The association between antibiotic prophylaxis and outcomes was adjusted by liver disease severity and by a propensity score.

RESULTS

The patients included in the study had mean MELD scores of 16, and 54% received antibiotic prophylaxis. Overall, antibiotic therapy was associated with lower risks of infection (adjusted odds ratio, 0.37; 95% confidence interval, 0.91-0.74) and mortality (adjusted odds ratio, 0.63; 95% confidence interval, 0.31-1.29). Among patients categorized as Child-Pugh class A given antibiotics, only 2% developed infections and the mortality rate was 0.4%. Among patients categorized as Child-Pugh class B given antibiotics, 6% developed infections, compared with 14% of patients who did not receive antibiotics; antibiotics did not affect mortality. Administration of antibiotics to patients categorized as Child-Pugh class C reduced infections and mortality by approximately 50%, compared with patients who did not receive antibiotics. MELD scores were not as useful as Child-Pugh class in identifying patients at risk for infection.

CONCLUSIONS

Based on a retrospective analysis of patients with cirrhosis and AVH, those categorized as Child-Pugh class A had lower rates of bacterial infection and lower mortality rates in the absence of antibiotic prophylaxis than patients categorized as classes B or C. The recommendation for routine antibiotic prophylaxis for this subgroup requires further evaluation.

Multiresistant bacterial infections in liver cirrhosis: Clinical impact and new empirical antibiotic treatment policies

Recently, important changes have been reported regarding the epidemiology of bacterial infections in liver cirrhosis. There is an emergence of multiresistant bacteria in many European countries and also worldwide, including the United States and South Korea. The classic empirical antibiotic treatment (third-generation cephalosporins, e.g., ceftriaxone, cefotaxime or amoxicillin-clavulanic acid) is still effective in infections acquired in the community, but its failure rate in hospital acquired infections and in some health-care associated infections is high enough to ban its use in these settings. The current editorial focuses on the different epidemiology of bacterial infections in cirrhosis across countries and on its therapeutic implications.

Clinical trial watch: reports from the AASLD Liver Meeting®, Boston, November 2014

The late and fast developments in the field of viral hepatitis were highly expected in the 2014 AASLD Liver Meeting®. Several combinations using direct acting antivirals (DAAs) showed high rates of sustained virological response (∼95%). Importantly, high cure rates were also demonstrated in patients with previous treatment failures, decompensated cirrhosis and hepatitis C recurrence after transplantation, making it clear that the interferon era is over (not so clear for ribavirin, which might still have a role in difficult-to-treat populations). Importantly, sustained virological response was associated with an improvement in liver function (MELD and Child-Pugh scores) in patients with advanced liver disease. In the field of liver cirrhosis, there were relevant data assessing the optimal empirical antibiotic therapy in patients with spontaneous bacterial peritonitis and high risk of resistant bacteria, as well as studies evaluating the role of terlipressin in type I hepatorenal syndrome and in septic shock. Regarding hepatic encephalopathy, two randomized trials suggest that the manipulation of the microbioma in patients with cirrhosis may have a role in the management of this complication. Some novel data on NASH support the beneficial effect of bariatric surgery (after failure of lifestyle intervention) in morbid obese patients with such diagnosis: clinical and histological improvements after surgery were evident in most patients with sufficient follow-up. A few controlled studies focused on the treatment of severe acute alcoholic hepatitis. Finally, several studies on hepatocellular carcinoma (HCC) were presented, covering topics such as ultrasound screening in cirrhosis, cryoablation treatment of early HCC and the relevance of downstaging in patients with HCC awaiting liver transplantation.

Long-term use of antibiotics and proton pump inhibitors predict development of infections in patients with cirrhosis

BACKGROUND & AIMS

Bacterial infections, particularly repeated infections, are significant causes of morbidity and mortality among patients with cirrhosis. We investigated and characterized risk factors for repeat infections in these patients.

METHODS

In a prospective study, we collected data from 188 patients hospitalized with cirrhosis and infections and enrolled in the North American Consortium for the Study of End-Stage Liver Disease (12 centers). Patients were followed up for 6 months after hospital discharge and data were analyzed on type of infections and factors associated with subsequent infections.

RESULTS

Six months after hospital discharge, 14% of subjects had received liver transplants, 27% died, and 59% were alive without liver transplantation. After discharge, 45% had subsequent infections, but only 26% of the subsequent infections occurred at the same site. Compared with patients not re-infected, patients with repeat infections were older and a higher proportion used proton pump inhibitors (PPIs) (P = .006), rifaximin (P < .001), or prophylactic therapy for spontaneous bacterial peritonitis (SBP) (P < .001). Logistic regression showed that SBP prophylaxis (odds ratio [OR], 3.44; 95% confidence interval [CI], 1.56-7.63), PPI use (OR, 2.94; 95% CI, 1.39-6.20), SBP at hospital admission (OR, 0.37; 95% CI, 0.15-0.91), and age (OR, 1.06; 95% CI, 1.02-1.11) were independent predictors of subsequent infections.

CONCLUSIONS

Patients hospitalized with cirrhosis and infections are at high risk for subsequent infections, mostly at different sites, within 6 months of index infection resolution. Those at highest risk include previously infected older patients receiving PPIs and/or SBP prophylaxis, although these associations do not prove that these factors cause the infections. New strategies are needed to prevent infections in patients with cirrhosis.