First-line treatment with cephalosporins in spontaneous bacterial peritonitis provides poor antibiotic coverage

Fluoroquinolones for the Prophylaxis of Spontaneous Bacterial Peritonitis in Patients with Liver Cirrhosis: Are They Losing Ground?

Spontaneous bacterial peritonitis (SBP) is the most common bacterial infection in cirrhotic patients. Historically, the bacterial spectrum was dominated by Gram-negative bacteria. However, recent studies showed that fluoroquinolone (FQ)-based prophylaxis promotes the intestinal overgrowth of Gram-positive bacteria and contributes to the selection of quinolone-resistant Gram-negative bacteria, increasing multidrug-resistant (MDR) organism infections. FQ resistance rates reach up to nearly one-third in community-acquired cases and 50% in hospital-acquired cases, raising concerns about FQ efficacy. Moreover, rare but serious side effects further limit FQ use. Predictive factors of FQ treatment failure have been identified, guiding management strategies. Rifaximin has emerged as a promising alternative for SBP prophylaxis, with encouraging results. This review aims to explore the shifting role of FQ-based SBP prophylaxis, focusing on the emerging concerns, side effects, and alternative strategies. While norfloxacin remains a first-line prophylactic in cirrhotic patients with low ascitic protein levels, its efficacy appears to be reduced in those with advanced liver failure or additional risk factors for MDR organisms. In these subgroups, alternative prophylactics, such as trimethoprim-sulfamethoxazole or rifaximin, may be preferable. We propose a risk-stratification approach to guide treatment selection, with further studies needed to refine these criteria.

Nosocomial vs healthcare associated vs community acquired spontaneous bacterial peritonitis: Network meta-analysis

INTRODUCTION

Spontaneous bacterial peritonitis (SBP) is a common complication in decompensated liver cirrhosis with ascitic fluid polymorphonuclear cell count > 250/mm3. Community acquired SBP (CA-SBP) occurs within the first 48 hours after hospital admission. Nosocomial SBP (N-SBP) occurs 48-72 hours after hospitalization. Healthcare associated SBP (HA-SBP) occurs in patients hospitalized in the preceding 90 days to months. We aim to evaluate mortality and resistance patterns to third generation cephalosporin among the three types.

METHODS

Multiple databases were systematically searched from inception through August 1st, 2022. Both pairwise (direct) and network (direct + indirect) meta-analysis was performed using a random effects model and DerSimonian Laird approach. Relative Risk (RR) with 95% confidence intervals (CI) were calculated. Network meta-analysis was conducted using frequentist approach.

RESULTS

A total of 14 studies with a total of 2302 SBP episodes were evaluated. On direct meta-analysis, mortality rate was higher in N-SBP compared to HA-SBP (RR 1.84, CI 1.43- 2.37) and CA-SBP (RR 1.69, CI 1.4-1.98), but not significantly different between HA-SBP and CA-SBP (RR=1.40, CI=0.71-2.76). Resistance to third generation cephalosporins was significantly higher in N-SBP compared to HA-SBP (RR=2.02, CI 1.26-3.22) and CA-SBP (RR=3.96, CI=2.50-3.60) as well as in HA-SBP compared to CA-SBP (RR=2.25, CI=1.33-3.81).

CONCLUSIONS

Our network meta-analysis shows increased mortality and antibiotic resistance with nosocomial SBP. We recommend clearly identifying such patients to manage accordingly as well as developing guidelines geared towards nosocomial infections to be able to optimally steer resistance patterns and reduce mortality.

Hibifolin, a Natural Sortase A Inhibitor, Attenuates the Pathogenicity of Staphylococcus aureus and Enhances the Antibacterial Activity of Cefotaxime

This study aimed to identify hibifolin as a sortase A (SrtA) inhibitor and to determine whether it could attenuate the virulence of methicillin-resistant Staphylococcus aureus (MRSA). We employed a fluorescence resonance energy transfer (FRET) assay to screen a library of natural molecules to identify compounds that inhibit SrtA activity. Fluorescence quenching assay and molecular docking were performed to verify the direct binding interaction between SrtA and hibifolin. The pneumonia model was established using C57BL/6J mice by MRAS nasal administration for evaluating the effect of hibifolin on the pathogenicity of MRSA. Herein, we found that hibifolin was able to inhibit SrtA activity with an IC₅₀ of 31.20 μg/mL. Further assays showed that the capacity of adhesion of bacteria to the host cells and biofilm formation was decreased in hibifolin-treated USA300. Results obtained from fluorescence quenching assay and molecular docking indicated that hibifolin was capable of targeting SrtA protein directly. This interaction was further confirmed by the finding that the inhibition activities of hibifolin on mutant SrtA were substantially reduced after mutating the binding sites (TRP-194, ALA-104, THR-180, ARG-197, ASN-114). The in vivo study showed that hibifolin in combination with cefotaxime protected mice from USA300 infection-induced pneumonia, which was more potent than cefotaxime alone, and no significant cytotoxicity of hibifolin was observed. Taken together, we identified that hibifolin attenuated the pathogenicity of S. aureus by directly targeting SrtA, which may be utilized in the future as adjuvant therapy for S. aureus infections.

IMPORTANCE We identified hibifolin as a sortase A (SrtA) inhibitor by screening the natural compounds library, which effectively inhibited the activity of SrtA with an IC₅₀ value of 31.20 μg/mL. Hibifolin attenuated the pathogenic behavior of Staphylococcus aureus, including adhesion, invasion, and biofilm formation. Binding assays showed that hibifolin bound to SrtA protein directly. Hibifolin improved the survival of pneumonia induced by S. aureus USA300 in mice and alleviated the pathological damage. Moreover, hibifolin showed a synergistic antibacterial effect with cefotaxime in USA300-infected mice.

Listerial Spontaneous Bacterial Peritonitis

Spontaneous bacterial peritonitis (SBP) is a severe complication of ascites often seen in advanced hepatic disease that is most commonly caused by Gram-negative bacilli. Here, we report a rare case of Listeria monocytogenes SBP, diagnosed by peritoneal fluid culture and responsive to ampicillin, in a patient with portal hypertension secondary to nodular regenerative hyperplasia. Because Listeria species are resistant to empiric SBP therapies and delays in treatment have been associated with increased mortality, they must be considered in high-risk patients.

An Epidemiological Meta-Analysis on the Worldwide Prevalence, Resistance, and Outcomes of Spontaneous Bacterial Peritonitis in Cirrhosis

Background and Aims: Spontaneous bacterial peritonitis (SBP) is a common and potentially fatal complication of liver cirrhosis. This study aims to analyze the prevalence of SBP among liver cirrhotic patients according to geographical location and income level, and risk factors and outcomes of SBP. Methods: A systematic search for articles describing prevalence, risk factors and outcomes of SBP was conducted. A single-arm meta-analysis was performed using generalized linear mix model (GLMM) with Clopper-Pearson intervals. Results: Ninety-Nine articles, comprising a total of 5,861,142 individuals with cirrhosis were included. Pooled prevalence of SBP was found to be 17.12% globally (CI: 13.63-21.30%), highest in Africa (68.20%; CI: 12.17-97.08%), and lowest in North America (10.81%; CI: 5.32-20.73%). Prevalence of community-acquired SBP was 6.05% (CI: 4.32-8.40%), and 11.11% (CI: 5.84-20.11%,) for healthcare-associated SBP. Antibiotic-resistant microorganisms were found in 11.77% (CI: 7.63-17.73%) of SBP patients. Of which, methicillin-resistant Staphylococcus aureus was most common (6.23%; CI: 3.83-9.97%), followed by extended-spectrum beta-lactamase producing organisms (6.19%; CI: 3.32-11.26%), and lastly vancomycin-resistant enterococci (1.91%; CI: 0.41-8.46%). Subgroup analysis comparing prevalence, antibiotic resistance, and outcomes between income groups was conducted to explore a link between socioeconomic status and SBP, which revealed decreased risk of SBP and negative outcomes in high-income countries. Conclusion: SBP remains a frequent complication of liver cirrhosis worldwide. The drawn link between income level and SBP in liver cirrhosis may enable further insight on actions necessary to tackle the disease on a global scale.

Spontaneous Bacterial Peritonitis in Cirrhotic Patients: A Shift in the Microbial Pattern? A Retrospective Analysis

<b><i>Introduction:</i></b> Over the last decade, a shift in the spontaneous bacterial peritonitis (SBP) microbial pattern toward an increasing incidence of gram-positive and multidrug-resistant (MDR) bacteria has been reported. Systematic surveillance of the local microbiological scenario and antibiotic resistance is crucial to SBP treatment success. The main objective of this study was to evaluate the microbiological profile and bacterial resistance of SBP pathogens in a Portuguese cohort to allow selection of the most appropriate empirical antibiotics. <b><i>Methods:</i></b> This is a single-center retrospective study including 63 adult cirrhotic patients with culture-positive SBP. Patients were identified using a hospital general diagnostic database and searching for all SBP events (neutrophil count in ascitic fluid ≥250/mm³) from January 1, 2012, to December 31, 2017. Patients were excluded if they had culture-negative SBP, secondary peritonitis, peritoneal dialysis, a liver transplant, or immunodeficiency. The site of SBP acquisition was classified as nosocomial if it was diagnosed 48 h or longer after hospitalization or as nonnosocomial if it was diagnosed within the first 48 h. MDR bacteria were those with an acquired resistance to at least 1 agent in 3 or more antimicrobial categories. All statistical analyses were carried out using IBM SPSS Statistics software version 22 (IBM, New York, USA). <b><i>Results:</i></b> The study cohort comprised 53 (84.1%) men. The mean age of the patients was 60.6 ± 11.2 years. Alcohol was the most common etiology (88.9%) and most patients had advanced liver cirrhosis (87.1%, Child C). Gram-negative bacteria were slightly more frequent than gram-positive bacteria (56.9 vs. 43.1%). <i>Escherichia coli</i> was the most common pathogen (33.8%). Nineteen (31.7%) bacteria were classified as MDR. Resistance to third-generation cephalosporins, quinolones, piperacillin-tazobactam, and carbapenems was found in 31.7, 35, 26.7, and 18.3% of the cases, respectively. The rates of gram-positive bacteria were similar between nosocomial and nonnosocomial episodes (45 vs. 42.2%; <i>p</i> = 0.835). MDR bacteria were more common in the nosocomial group (50 vs. 23.8%; <i>p</i> = 0.046). Resistance to third-generation cephalosporins (50 vs. 23.8%; <i>p</i> = 0.046), piperacillin-tazobactam (44.4 vs. 19.1%; <i>p</i> = 0.041), and carbapenems (33.3 vs. 11.9%; <i>p</i> = 0.049) occurred more frequently in nosocomial episodes. Resistance to first-line antibiotic occurred in 29.3% of the patients, being more common in the nosocomial group (44.4 vs. 22.5%; <i>p</i> = 0.089). <b><i>Conclusion:</i></b> Although gram-negative bacteria remain the most common causative microorganisms, our results emphasize the shift in SBP microbiological etiology, as almost half of the isolated microorganisms were gram positive. The emergence of bacteria resistant to traditionally recommended empirical antibiotics underlines the importance of basing this choice on local flora and antibiotic susceptibility data, allowing a more rational and successful use of antibiotics.

A retrospective analysis of cases of Spontaneous Bacterial Peritonitis in cirrhosis patients

Background & aims

Spontaneous Bacterial Peritonitis (SBP) is an infection in patients with cirrhosis and carries significant mortality. The management of SBP is evolving with the rise of multidrug resistant organisms. Our aim was to perform a retrospective analysis to determine if identification of bacteria in culture could aid in prognosis and provide information regarding optimal treatment.

Methods

We analyzed our 10-year experience of SBP in a single academic center (Northwestern Memorial Hospital). We obtained information regarding SBP prophylaxis, culture data and resistance patterns of bacteria, choice/duration of inpatient antibiotics, and key laboratory measurements and determined outcomes including mortality, hospital duration, and ICU stay.

Results

Patients with SBP had a 17.8% mortality and had culture positive SBP 34.4% of the time. Antimicrobial resistance was seen in 21.3% of cases and trended towards worsening mortality, with worsened mortality associated with first line use of piperacillin-tazobactam (p = 0.0001). Patients on SBP prophylaxis who developed SBP had improved mortality (p<0.0001) unless there was a positive culture, in which case patients had worsened mortality (p = 0.019). Patient with a higher PMN counts after repeat paracentesis had higher mortality (p = 0.02).

Conclusions

Our results show that SBP continues to be a morbid and deadly condition and identification of an organism is key in treatment. The standard initial antibiotic for SBP may need to be modified to reflect emerging resistant pathogens and gram-positive organisms. Further, antibiotic prophylaxis should be utilized only in select cases to prevent development of resistance.

Listeria monocytogenes as a Cause of Spontaneous Bacterial Peritonitis

Spontaneous bacterial peritonitis is a common and often serious complication of long standing ascites in the presence of advanced liver disease. We report a case of a 74-year-old woman with alcoholic cirrhosis admitted to our emergency department with a 1-week history of diffuse abdominal pain and increased abdominal perimeter. On physical examination, she had a significant abdominal distention and a positive fluid wave consistent with ascites. A diagnosis of spontaneous bacterial peritonitis was made and empiric therapy with ceftriaxone was started but the patient’s condition worsened. Four days later Listeria monocytogenes was detected in peritoneal fluid culture and ampicillin was initiated according to in vitro sensibility test. The patient completed 14 days of treatment with clinical and laboratory improvement. Listeria is an uncommon cause of spontaneous bacterial peritonitis. Clinicians should be aware of the uncommon agents of spontaneous bacterial peritonitis, mainly when there is not a proper response to therapy.

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.

Cephalosporin resistance in community acquired spontaneous bacterial peritonitis

Objective:

To determine 3^rd generation cephalosporin resistance in patients with community-acquired spontaneous bacterial peritonitis (SBP) using early response assessment.

Methods:

This prospective quasi-experimental study was carried out at Doctors Hospital & Medical Center from January 2016 to September 2018. Patients with cirrhosis and SBP were included. Third generation cephalosporins i.e. cefotaxime/ceftriaxone were used for treatment of SBP. Response after 48 hours was assessed and decline in ascitic fluid neutrophil count of < 25% of baseline was labelled as cephalosporin resistant. Carbapenem were used as second line treatment. Recovery and discharge or death of patients were primary end points.

Results:

Male to female ratio in 31 patients of SBP was 1.2/1 (17/14). Hepato-renal syndrome was diagnosed in 11(37.9%) patients. Cefotaxime was used for 16(51.6%) patients whereas ceftriaxone for 15(48.3%) patients. Early response of SBP was noted in 26(83.8%) patients while 5 (16.2%) were non-responders to cephalosporins. SBP resolved in all non-responding patients with i/v carbapenem. In-hospital mortality was 12.9% and had no association with cephalosporin resistance. High bilirubin (p 0.04), deranged INR (p 0.008), low albumin (p 0.04), high Child Pugh (CTP) score (p 0.03) and MELD scores (p 0.009) were associated with in-hospital mortality.

Conclusion:

Cephalosporin resistance was present in 16.2% of study patients with community-acquired SBP. Mortality in SBP patients is associated with advanced stage of liver disease.

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.

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 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.

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.

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.

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.

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.

Review article: spontaneous bacterial peritonitis--bacteriology, diagnosis, treatment, risk factors and prevention

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a severe and often fatal infection in patients with cirrhosis and ascites.

AIM

To review the known and changing bacteriology, risk factors, ascitic fluid interpretation, steps in performing paracentesis, treatment, prophylaxis and evolving perspectives related to SBP.

METHODS

Information was obtained from reviewing medical literature accessible on PubMed Central. The search term 'spontaneous bacterial peritonitis' was cross-referenced with 'bacteria', 'risk factors', 'ascites', 'paracentesis', 'ascitic fluid analysis', 'diagnosis', 'treatment', 'antibiotics', 'prophylaxis', 'liver transplantation' and 'nutrition'.

RESULTS

Gram-positive cocci (GPC) such as Staphylococcus, Enterococcus as well as multi-resistant bacteria have become common pathogens and have changed the conventional approach to treatment of SBP. Health care-associated and nosocomial SBP infections should prompt greater vigilance and consideration for alternative antibiotic coverage. Acid suppressive and beta-adrenergic antagonist therapies are strongly associated with SBP in at-risk individuals.

CONCLUSIONS

Third-generation, broad-spectrum cephalosporins remain a good initial choice for SBP treatment. Levofloxacin is an acceptable alternative for patients not receiving long-term flouroquinolone prophylaxis or for those with a penicillin allergy. For uncomplicated SBP, early oral switch therapy is reasonable. Alternative antibiotics such as pipercillin-tazobactam should be considered for patients with nosocomial SBP or for patients who fail to improve on traditional antibiotic regimens. Selective albumin supplementation remains an important adjunct in SBP treatment. Withholding acid suppressive medication deserves strong consideration, and discontinuing beta-adrenergic antagonist therapy in patients with end-stage liver disease and resistant ascites is standard care. Liver transplant evaluation should be undertaken for patients who develop SBP barring contraindications.

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.

Management of cirrhotic ascites

The most common complication to chronic liver failure is ascites. The formation of ascites in the cirrhotic patient is caused by a complex chain of pathophysiological events involving portal hypertension and progressive vascular dysfunction. Since ascites formation represents a hallmark in the natural history of chronic liver failure it predicts a poor outcome with a 50% mortality rate within 3 years. Patients with ascites are at high risk of developing complications such as spontaneous bacterial peritonitis, hyponatremia and progressive renal impairment. Adequate management of cirrhotic ascites and its complications betters quality of life and increases survival. This paper summarizes the pathophysiology behind cirrhotic ascites and the diagnostic approaches, as well as outlining the current treatment options. Despite improved medical treatment of ascites, liver transplantation remains the ultimate treatment and early referral of the patient to a highly specialized hepatology unit should always be considered.

Healthcare-associated and nosocomial bacterial infections in cirrhosis: predictors and impact on outcome

BACKGROUND & AIMS

Population-based data on the occurrence of healthcare-associated (HCA) and hospital-acquired (HA) bacterial infections in cirrhosis, their predictors, and their impact on outcome are limited.

METHODS

All patients with incident cirrhosis in 2001-2010 residing in an area of 600,000 inhabitants were retrospectively identified. All serious bacterial infections (resulting in or occurring during an inpatient hospital episode) during this period were registered. Acquisition type, site of infection, occurrence of infection-related acute-on-chronic liver failure (ACLF), acute kidney injury (AKI) and bacterial resistance were analysed. Patients were followed longitudinally until death, transplant or end of 2011.

RESULTS

A total of 398 serious infections occurred in 241/633 (38%) patients. Forty-seven per cent were HCA and 21% HA. Proton pump inhibitor (PPI) use was more common in HA (80%) vs. HCA (64%) vs. community-acquired (44%) infections (P < 0.001). In regression analysis, decompensated status, use of antibiotics and PPIs at infection diagnosis were independent predictors of HCA/HA infections (P < 0.05). After adjustment for confounders, HCA/HA infections were significantly related to infection-related ACLF (P < 0.05), but not severe sepsis, AKI or infection-related mortality (P > 0.05). Antibiotic-resistant infections were more frequent among HA (17%) than HCA (6%) or community-acquired (8%) infections (P < 0.05). Antibiotic-resistant HCA/HA infections were independently related to severe sepsis (P < 0.05).

CONCLUSIONS

In a population-based cirrhotic cohort, two-thirds of serious bacterial infections were HCA or HA. Decompensated liver disease, antibiotics and PPIs were predictors of serious HCA/HA infections, which were associated with the development of ACLF. Antibiotic resistance was frequent, especially in HA infections, and contributed to risk of severe sepsis.

Etiology and mortality of spontaneous bacterial peritonitis in liver transplant recipients: a cohort study

Spontaneous bacterial peritonitis (SBP) in liver transplantation (LT) recipients who progress to cirrhosis has received little attention. We investigated the adequacy of empirical treatment with third-generation cephalosporins for SBP in this population and the impact of transplantation on the evolution of the infection. We performed a cohort study with 138 SBP episodes: 19 in LT patients and 119 in non-LT patients. The etiology of SBP was identified for 73.7% of the episodes in LT patients and for 38.7% of the episodes in non-LT patients (P = 0.004). The main microorganisms in recipients were Escherichia coli (35.7%) and Streptococcus pneumoniae (21.4%). The etiologies did not differ in non-LT patients. The cephalosporin sensitivity was similar in the 2 groups (85.7% versus 78.4%, P = 0.7). LT recipients developed renal failure (57.9% versus 25.2%, P = 0.004) and encephalopathy (42.1% versus 22%, P = 0.08) more often than non-LT patients, and the mortality rates during episodes (52.6% versus 13.4%, P < 0.001) and at 6 months (70.6% versus 34.7%, P = 0.005) were higher. According to a multivariate analysis, the mortality-associated risk factors at diagnosis were a Model for End-Stage Liver Disease (MELD) score > 18 odds ratio (OR) = 6.1 and being an LT recipient (OR = 4.45). At 6 months, the risk factors for mortality were a MELD score > 18 (OR = 3.08), being an LT recipient (OR = 3.47), a known etiology (OR = 2.08), and the presence of hepatocellular carcinoma (OR = 3.73).

New determinants of prognosis in bacterial infections in cirrhosis

Despite major advances in the knowledge and management of liver diseases achieved in recent decades, decompensation of cirrhosis still carries a high burden of morbidity and mortality. Bacterial infections are one of the main causes of decompensation. It is very important for clinical management to be aware of the population with the highest risk of poor outcome. This review deals with the new determinants of prognosis in patients with cirrhosis and bacterial infections reported recently. Emergence of multiresistant bacteria has led to an increasing failure rate of the standard empirical antibiotic therapy recommended by international guidelines. Moreover, it has been recently reported that endothelial dysfunction is associated with the degree of liver dysfunction and, in infected patients, with the degree of sepsis. It has also been reported that relative adrenal insufficiency is frequent in the non-critically ill cirrhotic population and it is associated with a higher risk of developing infection, severe sepsis, hepatorenal syndrome and death. We advise a change in the standard empirical antibiotic therapy in patients with high risk for multiresistant infections and also to take into account endothelial and adrenal dysfunction in prognostic models in hospitalized patients with decompensated cirrhosis.

Third-generation cephalosporin-resistant spontaneous bacterial peritonitis: a single-centre experience and summary of existing studies

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is the most prevalent bacterial infection in patients with cirrhosis. Although studies from Europe have reported significant rates of resistance to third-generation cephalosporins, there are limited SBP-specific data from centres in North America.

OBJECTIVE

To evaluate the prevalence of, predictors for and clinical impact of third-generation cephalosporin-resistant SBP at a Canadian tertiary care centre, and to summarize the data in the context of the existing literature.

METHODS

SBP patients treated with both antibiotics and albumin therapy at a Canadian tertiary care hospital between 2003 and 2011 were retrospectively identified. Multivariate logistic regression was used to determine independent predictors of third-generation cephalosporin resistance and mortality.

RESULTS

In 192 patients, 25% of infections were nosocomial. Forty per cent (77 of 192) of infections were culture positive; of these, 19% (15 of 77) were resistant to third-generation cephalosporins. The prevalence of cephalosporin resistance was 8% with community-acquired infections, 17% with health care-associated infections and 41% with nosocomial acquisition. Nosocomial acquisition of infection was the only predictor of resistance to third-generation cephalosporins (OR 4.0 [95% CI 1.04 to 15.2]). Thirty-day mortality censored for liver transplantation was 27% (50 of 184). In the 77 culture-positive patients, resistance to third-generation cephalosporins (OR 5.3 [1.3 to 22]) and the Model for End-stage Live Disease score (OR 1.14 [1.04 to 1.24]) were independent predictors of 30-day mortality.

CONCLUSIONS

Third-generation cephalosporin-resistant SBP is a common diagnosis and has an effect on clinical outcomes. In an attempt to reduce the mortality associated with resistance to empirical therapy, high-risk subgroups should receive broader empirical antibiotic coverage.

Spontaneous ascitic fluid infection in liver cirrhosis: bacteriological profile and response to antibiotic therapy

BACKGROUND

Spontaneous ascitic fluid infection (SAI) is common in cirrhotic patients leading to significant morbidity and mortality. Third-generation cephalosporins are currently recommended as first-line therapy. We conducted a prospective study to determine bacterial etiology, susceptibility patterns, and clinical epidemiology including 1-month mortality of SAIs among patients with cirrhosis.

METHODS

Records of 600 patients with suspected SAI over a 4-year period were analyzed. Empirical cefotaxime/ceftriaxone was initiated in patients who had a neutrophil count >250/mm(3). Treatment failure was defined by absence of clinical improvement and/or significant decrease in neutrophil count of ascites (<25 % of base line value) by 72 h of therapy.

RESULTS

Seventy patients (11.6 %) had SAI, including 40 (57.1 %) culture-negative neutrocytic ascites (CNNA), 25 (35.8 %) spontaneous bacterial peritonitis (SBP), and five (7 %) monomicrobial non-neutrocytic bacterascites (MNB). Gram-negative bacilli (Klebsiella and E. coli) were the commonest organisms. The overall response rate to ceftriaxone was 62.8 % (44/70). Among culture-positive patients (SBP and MNB), sensitivity rates to ceftriaxone was 50 %, while it was 53.3 % for quinolones, 70 % for piperacillin-tazobactam, and 93.3 % for cefoperazone-sulbactam combination. Thirty-day mortality was lower for CNNA compared to SBP (20 % vs. 40 %, p < 0.001) and for patients with response compared to no response to first antibiotic (11.3 % vs. 53.8 %, p < 0.001).

CONCLUSION

The response of SAI to third-generation cephalosporins was low at our center. Cefoperazone-sulbactam could be a better alternative choice.

Spontaneous Bacterial Peritonitis Caused by Listeria monocytogenes Associated with Ascitic Fluid Lymphocytosis: A Case Report and Review of Current Empiric Therapy

Spontaneous bacterial peritonitis (SBP) is a potentially deadly complication of ascites. We describe a case of SBP caused by Listeria monocytogenes in a patient with alcoholic cirrhosis. This was associated with the unusual finding of ascitic fluid lymphocytosis, which previously had only been associated with tuberculoid or malignant ascites. Given increasing rates of cefotaxime-resistant SBP alongside the possibility of Listeriosis, the use of cefotaxime as first-line therapy in SBP should be reevaluated.

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

BACKGROUND & AIMS

There are limited data on the prevalence or predictors of antibiotic-resistant bacterial infections (AR-BI) in hospitalized patients with cirrhosis in North America. Exposure to systemic antibiotics is a risk factor for AR-BI; however, little is known about the effects of the increasingly used oral nonabsorbed antibiotics.

METHODS

We analyzed data from patients with cirrhosis and bacterial infections hospitalized in a liver unit at a US hospital between July 2009 and November 2010. Multivariate logistic regression was used to determine predictors of AR-BI. Data were analyzed on the first bacterial infection of each patient (n = 115), and a sensitivity analysis was performed on all infectious episodes per patient (n = 169).

RESULTS

Thirty percent of infections were nosocomial. Urinary tract infections (32%) and spontaneous bacterial peritonitis (24%) were most common. Of the 70 culture-positive infections, 33 (47%) were found to be antibiotic resistant (12 were vancomycin-resistant Enterococci, 9 were extended-spectrum β-lactamase-producing Enterobacteriaceae, 7 were quinolone-resistant gram-negative rods, and 5 were methicillin-resistant Staphylococcus aureus). Exposure to systemic antibiotics within 30 days before infection was associated independently with AR-BI, with an odds ratio (OR) of 13.5 (95% confidence interval [CI], 2.6-71.6). Exposure to only nonabsorbed antibiotics (rifaximin) was not associated with AR-BI (OR, 0.4; 95% CI, 0.04-2.8). In a sensitivity analysis, exposure to systemic antibiotics within 30 days before infection and nosocomial infection was associated with AR-BI (OR, 5.2; 95% CI, 1.5-17.7; and OR, 4.2; 95% CI, 1.4-12.5, respectively).

CONCLUSIONS

The prevalence of AR-BI is high in a US tertiary care transplant center. Exposure to systemic antibiotics within 30 days before infection (including those used for prophylaxis of spontaneous bacterial peritonitis), but not oral nonabsorbed antibiotics, is associated with development of an AR-BI.