Antibiotic resistance in healthcare-related and nosocomial spontaneous bacterial peritonitis

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 spontaneous bacterial peritonitis is associated with high mortality - a systematic review and meta-analysis

INTRODUCTION

It is unclear if Nosocomial Spontaneous Bacteria Peritonitis (NSBP) is associated with higher mortality compared with community acquired spontaneous bacterial peritonitis.

METHODS

Database search from inception to May 2022 was conducted. The databases included MEDLINE, EMBASE, Cochrane registry of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus. Inclusion criteria were as follows: adult patients, age >18 years, with a diagnosis of NSBP. Pooled estimates of mortality were calculated following the restricted maximum likelihood method. The mortality rate between NSBP and CA-SBP was reported as odds ratio (OR) and 95% confidence interval (CI). Data synthesis was obtained using random effects meta-analysis. Heterogeneity was reported as I2.

RESULTS

A total of 482 unique titles were screened. Twenty-two articles were included. A total of 2,145 patients with NSBP were included. Patients were followed for a median of 90 days. The pooled mortality rate of NSBP was 52.51% (95% CI 42.77-62.06%; I2 83.72%). Seven studies compared the mortality outcome of patients with NSBP and CA-SBP. NSBP was significantly associated with a higher rate of mortality (OR 2.78, 95% CI 1.87-4.11; I2 36.00%).

CONCLUSION

NSBP was associated with higher mortality rate compared to CA-SBP, which could be due to a higher rate of resistance organisms.

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.

A comparative study on nosocomial and community-acquired spontaneous bacterial peritonitis in patients with liver cirrhosis at a university hospital

BACKGROUND

The serious nature of spontaneous bacterial peritonitis (SBP) in patients with cirrhosis and the need for timely effective empirical antibiotic therapy in the context of the global surge of antimicrobial resistance and changing epidemiology necessitate a periodic review of the local epidemiologic features of the disease.

AIM

The aim of the study is to investigate the differences in bacterial profile and antibiotic resistance between nosocomial and community-acquired SBP in patients with liver cirrhosis to guide empirical antibiotic choices for better outcomes.

METHODS

This cross-sectional study included 95 ascitic cirrhotic patients diagnosed with SBP. According to the setting in which the infection was acquired, the patients were divided into two groups: nosocomial and community-acquired SBP. The bacterial profile and rates of multidrug resistance (MDR) phenotype and the extended-spectrum β-lactamase (ESBL) production among Gram-negative isolates in both groups were compared.

RESULTS

Escherichia coli was the most frequently isolated bacteria (60% of all isolates) followed by Klebsiella pneumoniae (11.4%). Gram-positive bacteria were only isolated from nosocomial SBP cases; the most common was Staphylococcus aureus (11.4%) followed by coagulase-negative staphylococci (5.7%). High rates of resistance to third-generation cephalosporins, the first-line empirical treatment of SBP, were detected (76.6-100% in nosocomial isolates and 25-87% in community isolates). Carbapenems, amikacin and gentamycin showed good activity against Gram-negative bacilli in both nosocomial and community-acquired isolates. MDR bacteria, including ESBL-producing Enterobacteriaceae, were significantly associated with nosocomial SBP.

CONCLUSION

The significant increase in MDR phenotype and ESBL production among nosocomial isolates necessitates a change in the initial empirical therapy for nosocomial SBP and carbapenems seem good alternatives.

Salmonella typhimurium as a causative agent of spontaneous bacterial peritonitis

Spontaneous bacterial peritonitis (SBP) is a common complication of liver cirrhosis and abdominal ascites, usually caused by organisms from the Enterobacteriaceae family. A woman in her 40s with a history of alcoholic liver cirrhosis presented to the hospital with dyspnoea, abdominal distention and diffuse abdominal pain. She was found to have sepsis and abdominal ascites, with elevated ascitic fluid neutrophil counts consistent with SBP. Culture of ascitic fluid revealed Salmonella typhimurium Further investigation revealed that the patient shared her home with a pet bearded dragon, a reptile known to carry Salmonella spp. She was treated with intravenous ceftriaxone and oral ciprofloxacin for a total of 14 days. S. typhimurium, likely transmitted to the patient from the pet reptile, is a rare pathogen in SBP and highlights the importance of environmental exposures in the management of this condition.

ANALYSIS OF HEALTHCARE ASSOCIATED AND HOSPITAL ACQUIRED INFECTIONS IN CRITICALLY ILL PATIENTS WITH CIRRHOSIS

ABSTRACT Background Bacterial infections occur in 43—59% of cirrhotic patients admitted to the intensive care unit with impact in morbidity and mortality. An increase in the frequency of multidrug-resistant (MDRO) and extensively drug-resistant (XDRO) organisms has been described in bacterial infections in cirrhotic patients with an adverse impact on survival. Objective To characterize community-acquired (CA), healthcare-associated (HCA), and hospital-acquired (HA) infections in cirrhotic patients and their impact in the occurrence of adverse outcomes. Methods This study included all cirrhotic patients admitted in an intensive care unit specialized in liver and gastrointestinal diseases in Brazil between January 2012 and June 2018. Frequency and topography of infections were retrospectively evaluated, as well as the frequency of MDRO and XDRO organisms, and their impact in occurrence of acute kidney injury, hepatorenal syndrome, acute-on-chronic liver failure, sepsis and mortality. Results A total of 374 infections were observed and classified as CA (22%), HCA (34%) and hospital-acquired (44%). Eighty-nine (54%) episodes of hospital-acquired infections were second infections. Spontaneous bacterial peritonitis (32%) and urinary tract infection (23%) were the most common infections. Culture-proven infections were positive in 61% of the cases, mainly gram-negative bacteria (73%). Acute kidney injury, hepatorenal syndrome and sepsis were observed, respectively, in 48%, 15% and 53% of the cases. MDRO and XDRO were seen, respectively, in 35% and 16%, mainly in HCA (48% vs 26% in CA infections, P=0.02) and hospital-acquired (58% vs 26% in CA infections, P=0.0009). Adverse outcomes were more frequently observed in subjects with hospital-acquired infections when compared to HCA and CA infections. Hospital-acquired, HCA and second infections were independently associated with in-hospital mortality. Conclusion Hospital-acquired, HCA and second infections are increasingly associated with either MDRO and/or XDRO and are independent predictors of in-hospital mortality. Their recognition and proper selection of appropriate empiric antibiotic regimens are important measures to reduce in-hospital mortality.

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

OBJECTIVES

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

Clinical characteristics and outcome of patients with enterococcal liver abscess

Epidemiology of bacteria isolated from pyogenic liver abscesses change, and an increase in enterococci has been reported in European hospitals. The aim of this study was to investigate the clinical characteristics and outcome of enterococcal PLA. We performed a retrospective analysis of patients with microbiologically confirmed PLA at three German university centers. Indicators of enterococcal PLA were determined using binary logistic regression, and survival analysis was performed using Kaplan-Meier statistics and Cox regression analysis. Enterococci were isolated in 51/133 (38%) patients with PLA. Patients with enterococcal PLA had smaller abscess diameter (4.8 vs. 6.7 cm, p = 0.03) than patients with non-enterococcal PLA, but had more frequent polymicrobial culture results. In univariate logistic regression analysis, alcohol abuse (OR 3.94, 95% CI 1.24-12.49, p = 0.02), hepatobiliary malignancies (OR 3.90, 95% CI 1.86-8.18, p < 0.001) and cirrhosis (OR 6.36, 95% CI 1.27-31.96, p = 0.02) were associated with enterococcal PLA. Patients with enterococcal PLA had a higher mortality than patients with non-enterococcal PLA (hazard ratio 2.92; 95% confidence interval 1.09-7.80; p = 0.03), which remained elevated even after excluding patients with hepatobiliary malignancies, cirrhosis, and transplant recipients in a sensitivity analysis. The increased mortality was associated with non-fecal enterococci but not in patients with Enterococcus faecalis. In this retrospective, multicenter study, enterococcal PLA was common and indicated an increased risk of mortality, underscoring the need for close clinical monitoring and appropriate treatment protocols in these patients.

Global epidemiological burden of fungal infections in cirrhosis patients: a systematic review with meta-analysis

BACKGROUND & AIMS

 Fungal infections (FIs) have serious implications, yet understated in cirrhosis. Therefore, we reviewed the epidemiology and trends of FIs among cirrhotics.

METHODS

Four electronic-databases were searched for full-text articles describing prevalence of FIs in cirrhosis. Studies from post-transplant, malignancy and classical-immuno-deficiency patients were excluded. A random-effects meta-analysis was done to pool estimates of FIs (overall, and by type and infection-site), and their variation(I² ) was explored on moderator-analysis and meta-regression. Risk of bias and asymmetry in estimates was assessed by a checklist and Eggers-regression, respectively.(CRD42019142782) RESULTS:  Thirty-four low-risk and four moderate-risk studies (31984 cirrhotics) were included. Pooled-estimates of overall-FIs (17 studies), invasive fungal infections (IFIs; 17 studies), invasive-candidiasis (23 studies), and invasive-aspergillosis (16 studies) in cirrhosis were 10.2%(6.0-16.9), 9.5%(5.4-16.2), 4.0%(2.0-8.0) and 2.8%(1.5-5.3); respectively (I² >90%;each). Site of FIs in decreasing order of pooled-prevalence was pulmonary, urinary-tract, bloodstream, peritoneal, esophageal, and cerebral. Geographic differences in these estimates were remarkable, with highest burden of overall-FIs from Belgium, USA, and India. Non-albicans-Candida and Aspergillus infections have increased over the last-decade in cirrhosis. Intensive-care-unit (ICU)-admitted and acute-on-chronic liver failure (ACLF) patients had the highest prevalence of IFIs. MELD-score(cases), bias-score, and sample size across studies were the predictors of variance in overall-FI-estimates. Diabetes, steroid and broad-spectrum antibiotic-exposure, and multiple organ failures were the common predispositions reported in patients with FIs.

CONCLUSIONS

 FIs impose a substantial burden in cirrhosis. ACLF and ICU-admission should be considered as a host factor for defining IFIs. Epidemiology of FIs can guide interpretation of biomarkers and antifungal treatment in cirrhosis.

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.

Advances in the pharmacological management of bacterial peritonitis

Introduction: Bacterial peritonitis is an infection with high mortality if not treated immediately. In the absence of an intraabdominal source of infection, bacterial peritonitis may arise in patients with liver cirrhosis, in patients on peritoneal dialysis (PD) for end-stage renal disease or in patients with tuberculosis. In patients with cirrhosis, bacterial peritonitis may trigger acute on chronic liver failure with substantial mortality despite optimal treatment. In patients on PD, peritonitis may make continuation of PD impossible, necessitating the switch to hemodialysis.Areas covered: Recovery from peritonitis and prevention of complications depend on timely pharmacological management. Challenges are the broad microbiological spectrum with growing rates of antimicrobial resistance, the underlying chronic liver or kidney failure and high rates of relapse. The authors provide a review of predisposing conditions, diagnosis, and prevention of bacterial peritonitis with a particular focus on the pharmacological management.Expert opinion: Diagnosis of the type of bacterial peritonitis is essential to pharmacological management. In patients with spontaneous bacterial peritonitis, broad-spectrum antibiotics should be given intravenously in conjunction with albumin. In patients on PD, antibiotic therapy should be preferably applied intraperitoneally with empirical coverage of gram-positive and gram-negative bacteria. Secondary peritonitis usually requires surgical or interventional treatment.

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

Background and aims

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

Methods

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

Results

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

Conclusions

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

Supplementary Information

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

A dual-caged resorufin probe for rapid screening of infections resistant to lactam antibiotics

The alarming increase of antimicrobial resistance urges rapid diagnosis and pathogen specific infection management. This work reports a rapid screening assay for pathogenic bacteria resistant to lactam antibiotics. We designed a fluorogenic N-cephalosporin caged 3,7-diesterphenoxazine probe CDA that requires sequential activations to become fluorescent resorufin. A series of studies with recombinant β-lactamases and clinically prevalent pathogens including Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae and Serratia marcescens demonstrated that CDA possessed superior sensitivity in reporting the activity of β-lactamases including cephalosporinases and carbapenemases. After a simple filtration, lactam-resistant bacteria in urine samples could be detected at 103 colony-forming units per milliliter within 2 hours.

Changes in the epidemiology and management of bacterial infections in cirrhosis

Patients with cirrhosis are susceptible to develop infections because of immune dysfunction, changes in microbiome and increase in bacterial translocation from the gut to systemic circulation. Bacterial infections can worse the clinical course of the disease, triggering the development of complications such as acute kidney injury, hepatic encephalopathy, organ failures and acute on chronic liver failure. In recent years, the spread of multi drug resistant bacteria made more challenging the management of infections in patients with cirrhosis. Hence, the mortality rate associated to sepsis is increasing in these patients. Therefore, the optimization of the management of infections has a high priority in cirrhosis. Herein we reviewed the recent changes in the epidemiology and the management of bacterial infections in patients with liver cirrhosis.

Prevalence and impact of antimicrobial resistance in gastrointestinal infections: A review

Antimicrobial resistance has become a worldwide problem due to its excessive increase in recent years. The aim of the present review was to bring together data from different articles describing the levels of antimicrobial resistance in the most common gastrointestinal infections reported across the globe. The literature search was carried out in Google Scholar, Medline, Embase, and Pubmed, with the terms "antimicrobial resistance", "resistance in gastrointestinal disorders", and "resistance in amoebiasis", in Spanish and English. Mexican treatment guidelines and consensuses from 2017 to the present were utilized. Publications from the last ten years were chosen to describe the level of resistance. They had adequate sample sizes, the Material and Methods sections were precise, and they included multicenter studies, national and international consensuses, meta-analyses, systematic reviews, and extensive texts. The final number of articles was 51. The microorganisms that demonstrated the highest percentage of resistance were Helicobacter pylori (metronidazole 50%-80%, clarithromycin 20%-40%, and levofloxacin 30%-35%), Clostridioides difficile (clindamycin 8.3%-100%, cephalosporines 51%), Campylobacter jejuni and Campylobacter coli (fluoroquinolones 85%), Escherichia coli (ampicillin 76.5%), Entamoeba histolytica (metronidazole 50%), and bacterial peritonitis (third-generation cephalosporines 40%, methicillin 85%). Antimicrobial resistance is reaching elevated percentages, making it necessary to evaluate the situation of each patient, to successfully treat gastrointestinal infections.

Spontaneous bacterial peritonitis due to carbapenemase-producing Enterobacteriaceae: Etiology and antibiotic treatment

Carbapenem antibiotics were first introduced in the 1980s and have long been considered the most active agents for the treatment of multidrug-resistant gram-negative bacteria. Over the last decade, carbapenem-resistant Enterobacteriaceae (CRE) have emerged as organisms causing spontaneous bacterial peritonitis. Infections caused by CRE have shown a higher mortality rate than those caused by bacteria sensitive to carbapenem antibiotics. Current antibiotic guidelines for the treatment of spontaneous bacterial peritonitis are insufficient, and rapid de-escalation of empiric antibiotic treatment is not widely recognized. This review summarizes the molecular characteristics, epidemiology and possible treatment of spontaneous bacterial peritonitis caused by CRE.

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.

Current Status and Prospects of Spontaneous Peritonitis in Patients with Cirrhosis

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

Clinical features and outcomes of bacterascites in cirrhotic patients: A retrospective, multicentre study

BACKGROUND & AIMS

Current guidelines on the management of bacterascites are limited. This multicentre, retrospective study investigated the clinical features and outcomes of cirrhosis patients with bacterascites.

METHODS

Two series of cirrhosis patients were evaluated. The first included 418 patients with ascites-positive cultures at 11 hospitals during 2012-2018. Clinical characteristics and outcomes were recorded. The second included 208 patients with sterile ascites from a prospective cohort (NCT02457637). Clinical features and outcomes of cirrhotic patients with or without bacterascites were investigated.

RESULTS

In the first series, bacterascites was diagnosed in 254/418 (60.8%) patients, and culture-positive spontaneous bacterial peritonitis (SBP) in 164/418 (39.2%) patients. Gram-positive bacteria were more prevalent in bacterascites patients than in culture-positive SBP patients (59.1% vs 22.0%; P < .001). For patients with acute-on-chronic liver failure (ACLF) in bacterascites and culture-positive SBP groups, the 28-day transplant-free mortality (41.3% vs 65.5%; P = .015) and the prevalence of in-hospital acute kidney injury (AKI) (84.8% vs 75%; P = .224). For patients without ACLF in the bacterascites (n = 208) and culture-positive SBP groups (n = 108), the 28-day transplant-free mortalities were 13% vs 13.9% (P = .822), the probabilities of progression to ACLF within 28 days were 10.1% vs 14.8% (P = .216) and the prevalences of in-hospital AKI were 14.4% vs 30.6% (P = .001). Bacterascites patients had higher 28-day mortality than those patients with sterile ascites, after propensity score matching (18.4% vs 8.6%; P = .010).

CONCLUSION

Bacterascites patients had non-negligible poor clinical outcomes, including in-hospital AKI, progression to ACLF and 28-day mortality. Future studies are warranted to expedite the diagnosis of bacterascites and optimize antibiotic treatment.

Frequency, characteristics and impact of multiple consecutive nosocomial infections in patients with decompensated liver cirrhosis and ascites

Background

Nosocomial infections are a particular threat for patients with liver cirrhosis. It is not uncommon that individuals develop even several consecutive infections during a single hospital stay. We aimed to investigate the impact and characteristics of multiple, consecutive nosocomial infections.

Methods

A total of 514 consecutive patients with liver cirrhosis and ascites were included and followed up for 28 days for nosocomial infection, death or liver transplantation (LTx). Laboratory values were assessed at the time of hospitalization as well as at the onset of each new infectious episode.

Results

58% (n = 298) of the patients developed at least one nosocomial infection and in 23% (n = 119) even multiple infections were documented during a single hospital stay. Consecutive infections usually occurred shortly after the previous episode. Spontaneous bacterial peritonitis (SBP) was the most common infection. However, the proportion of SBP declined from 43% at the first to only 31% at the third nosocomial infection (p = 0.096). In contrast, the likelihood for other, less common types of infection such as blood stream infections increased. Third nosocomial infections were also more likely to be linked to the detection of fungal pathogens (21% vs. 52%; p = 0.001). Each additional infectious episode had a dramatic detrimental impact on LTx-free survival that was independent from the stage of liver disease (adjusted-HR: 6.76, p = 0.002 for first nosocomial infection; adjusted-HR: 14.69, p<0.001 for second nosocomial infection; adjusted-HR: 24.95, p<0.001 for third nosocomial infection).

Conclusion

In patients with decompensated liver cirrhosis LTx-free survival significantly decreases with every consecutive infectious episode. Development of prevention strategies is urgently required.

Patients with cirrhosis and SBP: Increase in multidrug-resistant organisms and complications

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a serious complication in patients with liver cirrhosis. In recent years, it has been postulated that the rate of multidrug-resistant organisms (MDROs) is increasing, especially in nosocomial SBP patients. Aim of the present work was to investigate this hypothesis and its possible clinical consequences.

MATERIALS AND METHODS

One hundred and three culture-positive patients between 2007 and 2014 were compared with 81 patients between 2015 and 2017, to study the change of microbiological profiles and their clinical consequences. The cirrhosis patients with bacterascites requiring treatment were included as well.

RESULTS

The most prevalent Gram-negative bacteria isolated from ascites were Enterobacterales (31.6%) and in Gram-positive pathogens Staphylococci (22.8%). There was a significant increase in MDROs (22.3% ICU 40.7%, P = .048), accompanied by an increased incidence of sepsis (from 21.4% to 37.0%, P = .021), hepatorenal syndrome (from 40.8% to 58.0%, P = .007) and the need of catecholamine therapy (from 21.4% to 38.8%, P = .036). Nosocomial origin correlated with higher MDRO proportion, more complications and lower antimicrobial susceptibility rates in 12 commonly used antibiotics. MDROs were confirmed as an isolated predictor for inpatient mortality and complications in multivariable logistic regression.

CONCLUSIONS

The feeling in clinical practice that MDROs have increased in the last 11 years could be confirmed in our study in Munich, Germany. Nosocomial SBP correlated with significantly higher MDRO rates (nearly 50%) and complication rates. In our opinion, an antibiotic combination with comprehensive effect should be taken into account in nosocomial SBP patients in this region.

Culture-Positive Spontaneous Ascitic Infection in Patients with Acute Decompensated Cirrhosis: Multidrug-Resistant Pathogens and Antibiotic Strategies

PURPOSE

This study investigated multidrug-resistant (MDR) pathogens and antibiotic strategies of culture-positive spontaneous ascitic infection (SAI) in patients with acute decompensated cirrhosis.

MATERIALS AND METHODS

We retrospectively analyzed 432 acute decompensated cirrhotic patients with culture-positive SAI from 11 teaching hospitals in China (January 2012 to May 2018). A Cox proportional hazards model analysis was conducted to identify independent predictors of 28-day mortality.

RESULTS

A total of 455 strains were isolated from 432 ascitic culture samples. Gram-negative bacteria (GNB), gram-positive bacteria (GPB), and fungi caused 52.3, 45.5, and 2.2% of all SAI episodes, respectively. Episodes were classified as nosocomial (41.2%), healthcare-related (34.7%), and community-acquired (24.1%). Escherichia coli (13.4%) and Klebsiella pneumoniae (2.4%) were extended-spectrum β-lactamase producing isolates. The prevalence of methicillin-resistant Staphylococcus aureus was 1.1%. Ceftazidime, cefepime, aztreonam, and amikacin were recommended as first-line antibiotics agents for non-MDR GNB infections; piperacillin/tazobactam and carbapenems for MDR GNB in community-acquired and healthcare-related or nosocomial infections, respectively; and vancomycin or linezolid for GPB infections, regardless of drug-resistance status. Multivariate analysis revealed days of hospital stay before SAI, upper gastrointestinal bleeding, white blood cell count, alanine aminotransferase, serum creatinine concentration, total bilirubin, and international normalized ratio as key independent predictors of 28-day mortality.

CONCLUSION

MDR pathogens and antibiotic strategies were identified in patients with acute decompensated cirrhosis with culture-positive SAI, which may help optimize therapy and improve clinical outcomes.

Antimicrobial activity of LysSS, a novel phage endolysin, against Acinetobacter baumannii and Pseudomonas aeruginosa

OBJECTIVES

Multidrug-resistant (MDR) bacteria are a major public-health concern. Bacteriophage endolysins (lysins) can be used as novel antimicrobial agents against bacterial infections. In this study, a novel endolysin (LysSS) containing a lysozyme-like domain was evaluated for its antibacterial activity against various species of bacteria.

METHODS

The LysSS-encoding gene was analyzed and cloned and the LysSS recombinant protein was expressed and purified. Purified LysSS was used to determine its antimicrobial activity against various bacterial species in vitro and to measure its protection rate against Acinetobacter baumannii systemic infection in an in vivo murine model.

RESULTS

Recombinant LysSS showed activity against MDR A. baumannii, MDR Escherichia coli, MDR Klebsiella pneumoniae, MDR Pseudomonas aeruginosa and Salmonella sp. without pre-treatment with an outer membrane permeabiliser. Moreover, LysSS inhibited the growth of methicillin-resistant Staphylococcus aureus (MRSA). The minimum inhibitory concentration (MIC) of LysSS against 16 MDR A. baumannii strains ranged from 0.063-0.25mg/mL. LysSS had no cytotoxic effect on A549 human lung cells below 250μg/mL. In an animal model, mice infected with A. baumannii were protected (40% survival rate with 125μg LysSS) by intraperitoneal injection of LysSS.

CONCLUSION

The current results demonstrate that LysSS may be a novel and promising antimicrobial agent against MRSA and MDR Gram-negative bacteria, including A. baumannii and P. aeruginosa.

Evaluation of prophylactic antibiotic regimens on recurrence and mortality in spontaneous bacterial peritonitis

INTRODUCTION AND OBJECTIVES

Limited data describe current SBP epidemiology and specific secondary SBP prophylactic regimens, leading to variable prescribing practices. This work aims to compare 90-day and one-year SBP recurrence and mortality based on secondary SBP antibiotic prophylaxis regimens.

MATERIALS AND METHODS

We performed a retrospective cohort of patients >18 years with an SBP diagnosis from 2010 to 2015 at two academic institutions. Eligible patients had ascitic PMN counts ≥250cells/mm3 or a positive ascitic culture. Patients were compared based on secondary SBP prophylaxis regimens (i.e., daily, intermittent, or no prophylaxis).

RESULTS

Of 791 patients with ascitic fluid samples, 86 patients were included. Antibiotic prophylaxis included daily (n=34), intermittent (n=36), or no prophylaxis (n=16). Nearly half of SBP episodes had a positive ascitic fluid culture; 50% were gram-negative pathogens, and 50% were gram-positive pathogens. Daily and intermittent regimens had similar rates of recurrence at 90-days (19.4% vs. 14.7%, p=0.60) and one-year (33.3% vs. 26.5%, p=0.53). Similarly, mortality did not differ among daily and intermittent regimens at 90-days (32.4% vs. 30.6%, p=0.87) or one-year (67.6% vs. 63.9%, p=0.74). When comparing any prophylaxis vs. no prophylaxis, there were no differences in 90-day or one-year recurrence or mortality.

CONCLUSIONS

In patients with a history of SBP, our data indicate similar outcomes with daily, intermittent, or no secondary antibiotic prophylaxis. With available data, including ours, demonstrating a changing epidemiology for SBP pathogens, further data is required to determine if traditional approaches to secondary SBP prophylaxis remain appropriate.

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.

Spontaneous bacterial peritonitis in patients with cirrhosis: incidence, outcomes, and treatment strategies

Spontaneous bacterial peritonitis is the most frequent bacterial infection in patients with cirrhosis. The reported incidence varies between 7% and 30% in hospitalized patients with cirrhosis and ascites, representing one of their main complications. Outcomes in patients with spontaneous bacterial peritonitis are poor since acute kidney injury, acute-on-chronic liver failure, and death occur in as much as 54%, 60%, and 40% of the patients, respectively, at midterm. Early antibiotic treatment of spontaneous bacterial peritonitis is crucial. However, the landscape of microbiological resistance is continuously changing, with an increasing spread of multidrug-resistant organisms that make its current management more challenging. Thus, the selection of the empirical antibiotic treatment should be guided by the severity and location where the infection was acquired, the risk factors for multidrug-resistant organisms, and the available information on the local expected bacteriology. The use of albumin as a complementary therapy for selected high-risk patients with spontaneous bacterial peritonitis is recommended in addition to antibiotics. Even though antibiotic prophylaxis has proven to be effective to prevent spontaneous bacterial peritonitis, a careful selection of high-risk candidates is crucial to avoid antibiotic overuse. In this article we review the pathogenesis, risk factors, and prognosis of spontaneous bacterial peritonitis, as well as the current evidence regarding its treatment and prophylaxis.

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.

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.

Current and emerging pharmacotherapy for the treatment of bacterial peritonitis

INTRODUCTION

Spontaneous bacterial peritonitis (SBP) is the quintessential model of bacterial infection in cirrhotic patients. In these particularly frail subjects, infections clearly worsen prognosis increasing substantially mortality. Furthermore, treatment of SBP has become more challenging because of the growing impact of multidrug-resistant (MDR) bacteria.

AREAS COVERED

This review addresses the reasons behind the change in therapeutic recommendations for SBP that have occurred in the past few years, by focusing on the following aspects: the importance of an early appropriate empirical treatment, the difference between nosocomial and non-nosocomial forms and the overall microbiological shift (rise of Gram-positive bacteria and MDR strains) that have affected SBP.

EXPERT OPINION

Until recently, third-generation cephalosporins have represented the cornerstone of SBP treatment, a safe choice covering the most important causative agents, namely Enterobacteriaceae. Unfortunately, massive exposure to health systems makes cirrhotic patients prone to MDR infections, which poses significant challenges, all the while not forgetting to strike a balance between effective antimicrobial activity and the risk of toxicity in these fragile subjects. Moreover, there is sparse information about new antibiotics in cirrhotic patients and about drugs levels in ascitic fluid. Therefore, further research is needed to optimize the treatment of SBP.

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

Introduction

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

Methods

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

Results

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

Conclusion

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

Microbial Spectrum of Intra-Abdominal Abscesses in Perforating Crohn's Disease: Results from a Prospective German Registry

BACKGROUND

Intra-abdominal abscesses [IAAs] are common life-threatening complications in patients with Crohn's disease [CD]. In addition to interventional drainage and surgical therapy, empirical antibiotic therapy represents a cornerstone of treatment, but contemporary data on microbial spectra and antimicrobial resistance are scarce.

METHODS

We recruited 105 patients with CD and IAAs from nine German centres for a prospective registry in order to characterize the microbiological spectrum, resistance profiles, antibiotic therapy and outcome.

RESULTS

In 92 of 105 patients, microbial investigations of abscess material revealed pathogenic microorganisms. A total of 174 pathogens were isolated, with a median of 2 pathogens per culture [range: 1-6]. Most frequently isolated pathogens were E. coli [45 patients], Streptococcus spp. [28 patients], Enterococci [27 patients], Candida [13 patients] and anaerobes [12 patients]. Resistance to third-generation cephalosporins, penicillins with beta-lactamase inhibitors and quinolones were observed in 51, 36 and 35 patients, respectively. Seven patients had multiple-drug-resistant bacteria. Thirty patients received inadequate empirical treatment, and this was more frequent in patients receiving steroids or immunosuppression [37%] than in patients without immunosuppression [10%: p = 0.001] and was associated with a longer hospital stay [21 days vs 13 days, p = 0.003].

CONCLUSION

Based on antimicrobial resistance profiles, we herein report a high rate of inadequate empirical first-line therapy for IAAs in CD, especially in patients receiving immunosuppression, and this is associated with prolonged hospitalization.

Are third-generation cephalosporins still the empirical antibiotic treatment of community-acquired spontaneous bacterial peritonitis? A systematic review and meta-analysis

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a common complication among cirrhotic patients. Guidelines recommend third-generation cephalosporins (3GCs) as empiric antibiotic therapy (EAT) of SBP. Recently, a broad-spectrum EAT was shown to be more effective than cephalosporins in the treatment of nosocomial spontaneous bacterial peritonitis (N-SBP); however, the prevalence of 3GCs-resistant bacteria is high in the nosocomial setting and broad-spectrum EAT cannot be used in all cases of SBP.

AIM

The aim of this study was to evaluate the 3GCs resistance distribution between N-SBP and community-acquired spontaneous bacterial peritonitis (CA-SBP) to clarify whether 3GCs are still an effective therapeutic intervention for CA-SBP.

METHODS

We searched for studies that reported the aetiology of SBP and the resistance profile of both gram-positive and gram-negative bacteria in MEDLINE and Google Scholar databases (since 1 January 2000 to 30 April 2017). A meta-analysis was carried out to estimate the risk difference [relative risk (RR) and 95% confidence intervals (CIs)] for 3GCs resistance in N-SBP and CA-SBP. Heterogeneity was assessed using the I-test.

RESULTS

A total of eight studies were included, including 1074 positive cultures of ascitic fluid in cirrhotic patients; 462 positive cultures were from N-SBP and, among these, 251 (54.3%) were 3GCs resistant. Six hundred and twelve positive cultures were from CA-SBP and, among these, 207 (33.8%) were 3GCs-resistant SBP. A pooled RR of 3GCs resistance in N-SBP compared with CA-SBP showed a significant difference (RR=1.67, 95% CI: 1.14-2.44; P=0.008). We carried out two subgroup analyses: the first according to the median year of study observation (before vs. since 2008) and the second according to the country of the study (China vs. others). The studies carried out before 2008 (327 SBP-positive culture) showed a significantly higher risk for 3GCs-resistant strains in N-SBP compared with CA-SBP (RR=2.36, 95% CI: 1.39-3.99; P=0.001), whereas this was not found in SBP acquired after 2008 (RR=1.24, 95% CI: 0.83-1.84; P=0.29). N-SBP occurring in China had no significantly higher risk for 3GCs-resistant strains compared with CA-SBP (RR=1.44, 95% CI: 0.87-2.37; P=0.16).

CONCLUSION

Our findings suggest that although the pooled RR of 3GCs resistance in N-SBP compared with CA-SBP show that 3GCs are still an effective option for the treatment of CA-SBP, the subanalysis of studies that enroled patients in the last decade did not show a significant higher RR of 3GCs resistance in N-SBP compared with CA-SBP. Therefore, in centres where local patterns of antimicrobial susceptibility (with low rates of 3GCs resistance) are not available, 3GCs should not be used initially for CA-SBP treatment. Future studies are needed to confirm this trend of 3GCs resistance.

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.

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.