Increasing frequency of gram-positive cocci and gram-negative multidrug-resistant bacteria in spontaneous bacterial peritonitis

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.

Management of bacterial infection in the liver transplant candidate

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

Outcome of Enterococcus faecalis infective endocarditis according to the length of antibiotic therapy: Preliminary data from a cohort of 78 patients

Background

International guidelines recommend 4 weeks of treatment with ampicillin plus gentamicin (A+G) for uncomplicated native valve Enterococcus faecalis infective endocarditis (EFIE) and 6 weeks in the remaining cases. Ampicillin plus ceftriaxone (A+C) is always recommended for at least 6w, with no available studies assessing its suitability for 4w. We aimed to investigate differences in the outcome of EFIE according to the duration (4 versus 6 weeks) of antibiotic treatment (A+G or A+C).

Methods

Retrospective analysis from a prospectively collected cohort of 78 EFIE patients treated with either A+G or A+C.

Results

32 cases (41%) were treated with A+G (9 for 4w, 28%) and 46 (59%) with A+C (14 for 4w, 30%). No significant differences were found in 1-year mortality according to the type of treatment (31% and 24% in A+G and A+C, respectively; P = 0.646) or duration (26% and 27% at 4 and 6w, respectively; P = 0.863). Relapses were more frequent among survivors treated for 4w than in those treated for 6w (3/18 [17%] at 4w and 1/41 [2%] at 6w; P = 0.045). Three out of 4 (75%) relapses occurred in cirrhotic patients.

Conclusions

A 4-week course of antibiotic treatment might not be suitable neither for A+G nor A+C for treating uncomplicated native valve EFIE.

Bacterial Infections

Bacterial infections are the most significant infectious source of morbidity and mortality in cirrhotic patients. Bacteria infections result is both acute decompensation in chronic liver disease and mortality in patients with decompensated cirrhosis. Spontaneous bacterial peritonitis (SBP), bacteremia, pneumonia, urinary tract infections (UTI) and skin and soft tissue infection (SSTI) are the most significant sources of infection in cirrhosis. Bacterial infections can precipitate renal failure and worsening hepatic encephalopathy, and patients with sepsis and liver disease have higher rates of acute respiratory distress syndrome (ARDS) and coagulopathy.

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.

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

BACKGROUND

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Characteristics of infection and its impact on short-term outcome in patients with acute-on-chronic liver failure

Bacterial infections are an important cause of mortality in liver failure. However, the type of infection, predictors of infection, and their impact on outcomes in patients with acute-on-chronic liver failure (ACLF) are limited.A total of 389 patients with ACLF were admitted in this retrospective, corhort study. Once admitted, clinical data including first infection site, type (community-acquired, healthcare-associated, or nosocomial), and second infection occurrence during hospitalization were collected. The outcome was mortality within 90 days. Multivariable logistic regression models were preformed to predict second infection development and 90-day mortality. Survival probability curves were calculated by the Kaplan-Meier method.Among 389 patients, 316 (81.2%) patients had infection. The 90-day mortality of patients with and without infection was 52.2% and 16.4%, respectively (P <.001). The most common first infection was healthcare associated (51.3%), followed by nosocomial (30.1%) and community-acquired infections (18.7%). Respiratory tract infection, spontaneous bacterial peritonitis, and urinary tract infection were most prevalent. Gram-positive organism was more frequently seen than gram-negative organisms. Of note, fungi accounted for 15.9% of the total infection cases. During hospitalization, 26.6% patients developed second infections. The 90-day mortality of patients developed or did not develop a second infection were 67.9% and 46.6%, respectively (P <.001). Independent predictors of 90-day mortality in infected patients with ACLF were age, white blood cell (WBC) count, model for end-stage liver disease (MELD) score, hepatic encephalopathy (HE), and second infection.Infections (regardless of first or second infection) can increase the 90-day mortality significantly in patients with ACLF. And age, WBC count, MELD score, HE, and the presence of second infection are independent risk factors affecting 90-day mortality in patients with ACLF showing infection.

Rifaximin versus norfloxacin for prevention of spontaneous bacterial peritonitis: a systematic review

Aim

The aim of this systematic review is to evaluate the efficacy and safety of rifaximin in the prophylaxis of spontaneous bacterial peritonitis (SBP) as compared with norfloxacin.

Methods

We searched MEDLINE, CINAHL, Google Scholar and Cochrane databases from inception to January 2017. Reference lists of articles as well as conference proceedings were manually screened. We included studies that recruited patients with cirrhosis and ascites who met the criteria for primary or secondary SBP prophylaxis as defined by the European Association for the Study of the Liver and American Association for the Study of Liver Diseases. Two independent investigators reviewed the studies for eligibility, extracted the data and assessed study quality using the Cochrane risk of bias tool. The primary outcome was occurrence of SBP. Secondary outcomes included mortality and adverse events with therapy.

Results

Of the 435 studies identified, a total of five were included for full-text review. Four studies were eligible for the systematic review, three of which were randomised controlled trials and one was a prospective observational study. The population examined in majority of studies was primarily hepatitis C cirrhosis. The results of individual studies indicated either superior efficacy of rifaximin or no statistical difference between rifaximin and norfloxacin for SBP prophylaxis.

Conclusions

Moderate-quality evidence shows that long-term use of rifaximin appears to be a reasonable alternative to norfloxacin for SBP prevention in hepatitis C cirrhosis.

Nosocomial spontaneous bacterial peritonitis antibiotic treatment in the era of multi-drug resistance pathogens: A systematic review

AIM

To systematically review literature upon aetiology of nosocomial spontaneous bacterial peritonitis (N-SBP) given the rising importance of multidrug-resistant (MDR) bacteria.

METHODS

A literature search was performed on MEDLINE and Google Scholar databases from 2000 to 15th of November 2016, using the following search strategy: "spontaneous" AND "peritonitis".

RESULTS

The initial search through electronic databases retrieved 2556 records. After removing duplicates, 1958 records remained. One thousand seven hundred and thirty-five of them were excluded on the basis of the screening of titles and abstract, and the ensuing number of remaining articles was 223. Of these records, after careful evaluation, only 9 were included in the qualitative analysis. The overall proportion of MDR bacteria turned out to be from 22% to 73% of cases across the studies.

CONCLUSION

N-SBP is caused, in a remarkable proportion, by MDR pathogens. This should prompt a careful re-assessment of guidelines addressing the treatment of this clinical entity.

Carbapenem-resistant Enterobacteriaceae in the community: a scoping review

Carbapenem antibiotics are used as a last resort to treat serious Gram-negative bacteria (GNB) infections; however, carbapenemase-producing strains of GNB have emerged as a major source of resistance. Owing to the highly transmissible nature of plasmid-borne carbapenemases, numerous reports have warned about the likely spread into the community from healthcare settings. Since the prevalence of carbapenem-resistant Enterobacteriaceae (CRE) in the community is largely unknown, we conducted a scoping review of the literature to assess the percentage of CRE isolates that could be associated with the community. Initially, 361 studies were assessed and 15 met the inclusion criteria. Although 5 studies (33.3%) found no community-associated CRE, the remaining 10 studies identified percentages ranging from 0.04% to 29.5% of either community-associated or community-onset CRE among their samples, with US-based studies alone ranging from 5.6 to 10.8%. The presence of CRE in the community poses an urgent public health threat.

Nosocomial and Community-Acquired Spontaneous Bacterial Peritonitis in patients with liver cirrhosis in China: Comparative Microbiology and Therapeutic Implications

Spontaneous bacterial peritonitis (SBP) is a common complication of liver cirrhosis. This study was performed to compare the microbiological characteristics of nosocomial and community-acquired episodes of bacterial peritonitis in China. Five hundred and seventy-five strains were isolated from the ascitic fluid of cirrhotic patients from the Beijing 302 Hospital from January 2014 to December 2014. The patients in the community-acquired SBP (n = 311) and the nosocomial SBP (n = 264) groups exhibited significant differences in clinical symptoms (P < 0.01). In both groups, most of the bacteria were Escherichia coli, Klebsiella pneumoniae, coagulase-negative staphylococcus and Enterococcus. There were more frequent gram-positive cocci (G⁺ C) in the nosocomial group (n = 170). Compared with the community-acquired group, the proportion of Enterococcus was significantly increased in the nosocomial group (9.0% vs. 16.6%, P < 0.05). The resistance rate of the main pathogenic bacteria to the recommended first-line drug in the guideline was very high. Community-acquired and nosocomial SBP groups exhibited differences in clinical symptoms and antibiotic susceptibility tests. Optimal treatments should be provided for these patients. We recommend that cefoperazone/sulbactam or piperacillin/tazobactam should be used for the empirical treatment of SBP.

A Real-World Evaluation of Repeat Paracentesis-guided Management of Spontaneous Bacterial Peritonitis

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a common infection in cirrhosis associated with high mortality. More than 20% of patients with SBP do not respond to initial antibiotics. Guidelines differ in recommendations to repeat paracentesis (retap) to confirm antibiotic efficacy. We aim to evaluate the effect of retap-guided management of SBP on antibiotic escalation and 30-day transplant-free survival.

MATERIALS AND METHODS

Retrospective cohort study of cirrhotic patients with SBP admitted to a single transplant center from 2010 to 2014. Patients were divided into 2 groups: retap-guided management versus no retap. Prevalence of initial antibiotic treatment failure, defined as <25% decrease in ascitic polymorphonuclear cells, and factors associated with treatment failure, antibiotic escalation and 30-day transplant-free survival were evaluated.

RESULTS

Out of 210 patients, 146 (age 58, 74% male, mean model for end-stage liver disease score, 25) had retap and treatment failure was noted in 28 (22%). Gram-positive bacteria accounted for 44% of all positive cultures and third-generation cepahalosporin resistance was noted in 23%. Thirty-day transplant-free survival was 72% and 62% in retap and control groups, respectively (P=0.07). Treatment failure independently doubled the 30-day mortality rate (hazard ratio: 2.15, 1.03 to 4.50, P=0.04). After adjusting for age, model for end-stage liver disease and nosocomial infection, retap-guided management was not associated with improved survival (P=0.34).

CONCLUSIONS

The prevalence of initial treatment failure is high (22%) in patients with SBP and doubles the 30-day mortality risk, supporting recommendations to retap all patients with SBP.

Antibiotic resistance in healthcare-related and nosocomial spontaneous bacterial peritonitis

BACKGROUND

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

The challenges of multi-drug-resistance in hepatology

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

New antibiotic strategies in patients with cirrhosis and bacterial infection

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

An empirical broad spectrum antibiotic therapy in health-care-associated infections improves survival in patients with cirrhosis: A randomized trial

Early diagnosis and appropriate treatment of infections in cirrhosis are crucial because of their high morbidity and mortality. Multidrug-resistant (MDR) infections are on the increase in health care settings. Health-care-associated (HCA) infections are still frequently treated as community-acquired with a detrimental effect on survival. We aimed to prospectively evaluate in a randomized trial the effectiveness of a broad spectrum antibiotic treatment in patients with cirrhosis with HCA infections. Consecutive patients with cirrhosis hospitalized with HCA infections were enrolled. After culture sampling, patients were promptly randomized to receive a standard or a broad spectrum antibiotic treatment (NCT01820026). The primary endpoint was in-hospital mortality. Efficacy, side effects, and the length of hospitalization were considered. Treatment failure was followed by a change in antibiotic therapy. Ninety-six patients were randomized and 94 were included. The two groups were similar for demographic, clinical, and microbiological characteristics. The prevalence of MDR pathogens was 40% in the standard versus 46% in the broad spectrum group. In-hospital mortality showed a substantial reduction in the broad spectrum versus standard group (6% vs. 25%; P = 0.01). In a post-hoc analysis, reduction of mortality was more evident in patients with sepsis. The broad spectrum showed a lower rate of treatment failure than the standard therapy (18% vs. 51%; P = 0.001). Length of hospitalization was shorter in the broad spectrum (12.3 ± 7 days) versus standard group (18 ± 15 days; P = 0.03). Five patients in each group developed a second infection during hospitalization with a similar prevalence of MDR (50% broad spectrum vs. 60% standard).

CONCLUSIONS

A broad spectrum antibiotic therapy as empirical treatment in HCA infections improves survival in cirrhosis. This treatment was significantly effective, safe, and cost saving.

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

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

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

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

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

Predictive Factors of Spontaneous Bacterial Peritonitis Caused by Gram-Positive Bacteria in Patients With Cirrhosis

Spontaneous bacterial peritonitis (SBP) in patients with cirrhosis is typically caused by gram-negative bacteria. However, the number of SBP cases due to gram-positive bacteria is steadily increasing. To date, little is known about the predictive factors involved in SBP infections.We performed a retrospective cohort study of patients (>18 years) with SBP due to gram-positive and -negative bacteria who were enrolled from January 2006 to December 2013 at Severance Hospital in Seoul, Korea where the incidences of hepatitis B virus associated chronic liver disease, cirrhosis, and hepatocellular carcinoma are high. Only the 1st SBP episode for each patient within the study period was included in our analysis.We identified 77 patients with cirrhosis and SBP. Of these, 27 patients (35%) had gram-positive bacterial infections and 50 patients (65%) had gram-negative bacterial infections. Our univariate analysis revealed that an early stage of cirrhosis (P = 0.004), lower creatinine level (P = 0.011), lower Sequential Organ Failure Assessment (SOFA) score (P = 0.001), lower Model for End-Stage Liver Disease score (P = 0.005), and use of systemic antibiotics within 30 days before SBP diagnosis (P = 0.03) were significantly associated with gram-positive bacterial infections. Our multivariate analysis indicated that the use of systemic antibiotics within 30 days before SBP diagnosis (odds ratio, 3.94; 95% CI, 1.11-13.96; P = 0.033) and a lower SOFA score (odds ratio, 0.56; 95% CI, 0.37-0.86; P = 0.007) were independent predictive factors of SBP caused by gram-positive bacterial infections in patients with cirrhosis. However, we did not observe a statistically significant difference in the 28-day mortality between the gram-positive and -negative bacterial infection groups (40.7% vs 46.0%, respectively; P = 0.407).In this study, the incidence rate of SBP caused by gram-positive bacteria in patients with cirrhosis was similar to the rates reported in recently published studies. Furthermore, the use of systemic antibiotics within 30 days before SBP diagnosis and a lower SOFA score were significantly associated with SBP caused by gram-positive bacteria in patients with cirrhosis.

Enteroccocus pallens as a potential novel human pathogen: three cases of spontaneous bacterial peritonitis

Introduction:

Enterococcus pallens is one of the four yellow-pigmented members of the genus Enterococcus. To date, a single report of E. pallens isolated from a human sample has been published.

Case presentation:

We report three cases of E. pallens spontaneous bacterial peritonitis in patients with liver cirrhosis that all occurred in Quebec, Canada. Ascitic fluid analysis revealed the presence of E. pallens in culture. Identification was made by classical biochemical testing and MALDI-TOF MS, as well as 16S rRNA and elongation factor (tuf) gene sequencing. Two of the three patients recovered after antimicrobial treatment.

Conclusion:

This report identifies E. pallens as a novel human pathogen that appears to possess particular but as-yet unidentified virulence factors that favour the development of peritoneal fluid infections, as previously reported for other Enterococcus species. Clinical microbiologist should be aware of this micro-organism which can be identified by phenotypic and molecular methods.

Could Adherence to Quality of Care Indicators for Hospitalized Patients With Cirrhosis-Related Ascites Improve Clinical Outcomes?

OBJECTIVES

The diagnosis of cirrhotic ascites is associated with significant morbidity, mortality, and reduced health-related quality of life. Adherence by health professionals to quality indicators (QIs) of care for ascites is low. We evaluated the effect of adherence to ascites QIs on clinical outcomes for patients hospitalized with new onset cirrhotic ascites.

METHODS

The medical records of 302 patients admitted with new onset cirrhotic ascites were interrogated for demographic and clinical data and adherence to eight Delphi panel-derived QIs for ascites management. Associations between adherence to each QI and 30-day emergent readmission and 90-day mortality were analyzed.

RESULTS

The majority of patients were males (68.9%) over 50 years of age (mean 57±12.83 years) with alcohol-related cirrhosis (59%). Twenty-nine percent were readmitted within 30 days. Patients who received an abdominal paracentesis within 30 days of ascites diagnosis (QI 1, relative risk (RR) 0.41, P=0.004) or during index hospitalization (QI 2, RR 0.57, P=0.006) were significantly less likely to experience a 30-day emergent readmission. Baseline serum bilirubin >2.5 mg/dl was associated with increased 30-day cirrhosis-related readmission (RR 1.51, P=0.03). A total of 18.5% of patients died within 90 days of index admission; median interval to death was 139 days (37-562 days). Pneumonia was the most frequent cause of death. Independent predictors of 90-day mortality included older age (odds ratio (OR) 1.03, P=0.03), increased Model for End-stage Liver Disease (MELD)-Na score (OR 1.06, P=0.05), primary SBP prophylaxis (QI 7, OR 2.30, P=0.04), and readmission within 30 days (OR 30.26, P<0.001). Discharge prescription of diuretics (QI 8, OR 0.28, P=0.01) was associated with reduced 90-day mortality.

CONCLUSIONS

Early paracentesis in patients with new onset cirrhotic ascites lowers 30-day readmission rates, and early initiation of diuretic therapy lowers 90-day mortality.

Clinical and pathophysiological consequences of alterations in the microbiome in cirrhosis

Cirrhosis is a major cause of mortality worldwide. Exponential rises in prevalence have been observed secondary to increases in obesity and alcohol consumption. Multiple lines of evidence implicate gut-derived bacteria and bacterial ligands as a central driver of pathogenesis. Recent developments in culture-independent techniques have facilitated a more accurate description of microbiome composition in cirrhosis and led to the description of measures of dysbiosis shown to be associated with disease. More importantly, metagenomic studies are adding to an understanding of the functional contribution of the microbiota and may prove to be a more clinically relevant biomarker than phylogenetic studies. Much like other dysbiotic states such as inflammatory bowel disease, the microbiota in cirrhosis is characterized by a low microbial and genetic diversity. Therapeutic strategies to diminish this process are currently limited to selective intestinal decontamination with antibiotics. This review summarizes the available data and develops a framework for the use of current and future treatment strategies to diminish the consequences of dysbiosis in cirrhosis. Interventional strategies to bind bacterial products in the gut lumen and blood, and modulate the magnitude of host sensing mechanisms remain an unmet clinical need. A greater understanding of the host-microbiota interaction in cirrhosis is of key importance to inform future interventional strategies to diminish the currently escalating burden of the disease.

Spontaneous Bacterial Peritonitis Due to Methicillin-Resistant Staphylococcus Aureus in a Patient with Cirrhosis: The Potential Role for Daptomycin and Review of the Literature

Gram-positive cocci are emerging causes of spontaneous bacterial peritonitis (SBP), especially in patients with healthcare-associated infections. We report the case of a 68-year-old man with hepatitis C virus and alcohol-related cirrhosis who developed SBP due to methicillin-resistant Staphylococcus aureus treated with daptomycin. We discuss the potential role of daptomycin in this setting with a review of the literature about the use of daptomycin in primary or secondary bacterial peritonitis.

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

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

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

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

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

Bacterial infections in alcoholic and nonalcoholic liver cirrhosis

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

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

BACKGROUND & AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The INCA trial (Impact of NOD2 genotype-guided antibiotic prevention on survival in patients with liver Cirrhosis and Ascites): study protocol for a randomized controlled trial

BACKGROUND

Patients with liver cirrhosis have a highly elevated risk of developing bacterial infections that significantly decrease survival rates. One of the most relevant infections is spontaneous bacterial peritonitis (SBP). Recently, NOD2 germline variants were found to be potential predictors of the development of infectious complications and mortality in patients with cirrhosis. The aim of the INCA (Impact of NOD2 genotype-guided antibiotic prevention on survival in patients with liver Cirrhosis and Ascites) trial is to investigate whether survival of this genetically defined high-risk group of patients with cirrhosis defined by the presence of NOD2 variants is improved by primary antibiotic prophylaxis of SBP.

METHODS/DESIGN

The INCA trial is a double-blind, placebo-controlled clinical trial with two parallel treatment arms (arm 1: norfloxacin 400 mg once daily; arm 2: placebo once daily; 12-month treatment and observational period). Balanced randomization of 186 eligible patients with stratification for the protein content of the ascites (<15 versus ≥ 15 g/L) and the study site is planned. In this multicenter national study, patients are recruited in at least 13 centers throughout Germany. The key inclusion criterion is the presence of a NOD2 risk variant in patients with decompensated liver cirrhosis. The most important exclusion criteria are current SBP or previous history of SBP and any long-term antibiotic prophylaxis. The primary endpoint is overall survival after 12 months of treatment. Secondary objectives are to evaluate whether the frequencies of SBP and other clinically relevant infections necessitating antibiotic treatment, as well as the total duration of unplanned hospitalization due to cirrhosis, differ in both study arms. Recruitment started in February 2014.

DISCUSSION

Preventive strategies are required to avoid life-threatening infections in patients with liver cirrhosis, but unselected use of antibiotics can trigger resistant bacteria and worsen outcome. Thus, individualized approaches that direct intervention only to patients with the highest risk are urgently needed. This trial meets this need by suggesting stratified prevention based on genetic risk assessment. To our knowledge, the INCA trial is first in the field of hepatology aimed at rapidly transferring and validating information on individual genetic risk into clinical decision algorithms.

TRIAL REGISTRATIONS

German Clinical Trials Register DRKS00005616 . Registered 22 January 2014. EU Clinical Trials Register EudraCT 2013-001626-26 . Registered 26 January 2015.

Toward culture-free Raman spectroscopic identification of pathogens in ascitic fluid

The identification of pathogens in ascitic fluid is standardly performed by ascitic fluid culture, but this standard procedure often needs several days. Additionally, more than half of the ascitic fluid cultures are negative in case of suspected spontaneous bacterial peritonitis (SBP). It is therefore important to identify and characterize the causing pathogens since not all of them are covered by the empirical antimicrobial therapy. The aim of this study is to show that pathogen identification in ascitic fluid is possible by means of Raman microspectroscopy and chemometrical evaluation with the advantage of strongly increased speed. Therefore, a Raman database containing more than 10000 single-cell Raman spectra of 34 bacterial strains out of 13 different species was built up. The performance of the used statistical model was validated with independent bacterial strains, which were grown in ascitic fluid.

Clinical outcomes of spontaneous bacterial peritonitis due to extended-spectrum beta-lactamase-producing Escherichia coli or Klebsiella pneumoniae: a retrospective cohort study

PURPOSE

The aim of this study was to (1) evaluate the clinical outcomes of spontaneous bacterial peritonitis (SBP) due to extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli or Klebsiella pneumoniae (EK) and (2) investigate the relationship between the adequacy of initial antibiotic treatments and patient outcomes.

METHODS

We conducted a retrospective cohort study of cirrhotic patients with SBP caused by EK. We evaluated the 30-day mortality rate and used Cox proportional hazard models to identify risk factors for mortality.

RESULTS

Between January 2006 and December 2012, a total of 231 episodes of SBP due to EK were recorded. Among them, 52 were caused by ESBL-producing EK (ESBL-EK). The 30-day mortality rate was significantly higher in patients with SBP due to ESBL-EK than in those with non-ESBL-producing EK (non-ESBL-EK) (34.6 vs. 18.4 %, respectively; p = 0.013). Multivariate analysis revealed that ESBL production [adjusted HR (aHR) 1.82, 95 % confidence interval (CI) 1.00-3.31], nosocomial infection (aHR 2.24, 95 % CI 1.26-3.95), septic shock (aHR 4.84, 95 % CI 2.70-8.65), higher Child-Pugh score (aHR 1.57, 95 % CI 1.28-1.92), and higher Charlson comorbidity index (aHR 1.37, 95 % CI 1.15-1.64) were independent risk factors for 30-day mortality in the total cohort. When we analyzed patients with SBP due to ESBL-EK separately, septic shock (aHR 3.64, 95 % CI 1.40-9.77), accompanying bacteremia (aHR 3.71, 95 % CI 1.37-10.08), and hepatocellular carcinoma (aHR 3.21, 95 % CI 1.20-8.56) were independent risk factors.

CONCLUSIONS

Both 7- and 30-day mortalities for SBP due to ESBL-EK were significantly higher than for SBP due to non-ESBL-EK. Initial antibiotic choice was not associated with poor clinical outcomes in patients with SBP due to ESBL-EK.

Patterns of antimicrobial resistance in the causative organisms of spontaneous bacterial peritonitis: a single centre, six-year experience of 1981 samples

Background/Aims. Spontaneous bacterial peritonitis (SBP) is one of the leading causes of morbidity and mortality in patients with cirrhosis. This study aims to determine the microbial agents of SBP and the pattern of antibiotic resistance, in a large number of ascitic samples. Methodology. In a cross-sectional, single center, hospital based study, 1981 consecutive ascitic fluid samples were recruited from 2005 to 2011. Samples were dichotomized into three-year periods, in order to assess the trend of resistance to the first-line empirical antibiotics. Results. SBP was found in 482 (24.33%) of samples, of which 314 (65.15%) were culture positive. The most prevalent isolated pathogen was E. coli (33.8%), followed by staphylococcus aureus (8.9%) and Enterococcus (8.6%). No significant changes in the proportion of gram-negative/gram-positive infections occurred during this period. A percentage of resistant strains to cefotaxime (62.5%, 85.7%), ceftazidim (73%, 82.1%), ciprofloxacin (30, 59.8%), ofloxacin (36.8%, 50%), and oxacilin (35%, 51.6%) were significantly increased. E. coli was most sensitive to imipenem, piperacillin-tazobactam, amikacin, ceftizoxime, and gentamicin. Conclusions. The microbial aetiology of SBP remains relatively constant. However, the resistance rate especially to the first-line recommended antibiotics was significantly increased. This pattern must be watched closely and taken into account in empirical antibiotic treatment.