Daily Norfloxacin vs. Weekly Ciprofloxacin to Prevent Spontaneous Bacterial Peritonitis: A Randomized Controlled Trial

Antibiotics in decompensated liver disease - who, when and for how long?

INTRODUCTION

Bacterial infections are a leading cause of hospitalization and mortality in patients with decompensated cirrhosis. Antibiotic prophylaxis in cirrhotic patients has demonstrated significant short-term reductions in bacterial infections in randomized controlled trials, but at the cost of drug resistance and with uncertain survival benefits.

AREAS COVERED

This review examines antibiotic use in cirrhosis, focusing on patients most likely to benefit from antibiotic prophylaxis, management strategies for infections through risk-based antibiotic selection and timely treatment initiation, challenges posed by the emergence of multidrug-resistant organisms, and principles of antimicrobial stewardship.

EXPERT OPINION

The efficacy of prophylaxis has decreased over time, and current registry data have questioned its use, emphasizing the need for better risk-based individualized strategies. When bacterial infections occur, the efficacy of antimicrobial therapies depends heavily on local epidemiological patterns and individual patient risk factors, necessitating tailored antibiotic selection based on regional resistance data and specific clinical scenarios. Nosocomial infections, colonization with multidrug-resistant organisms, and prior exposure to systemic antibiotics are key risk factors that should guide empirical therapy selection. Until evidence-based algorithms are available, clinicians should continue to adopt individualized approaches, guided by available evidence, local specificities, and antimicrobial stewardship principles to optimize patient outcomes.

Norfloxacin versus alternative antibiotics for prophylaxis of spontaneous bacteria peritonitis in cirrhosis: a systematic review and meta-analysis

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a life-threatening complication in patients with advanced cirrhosis. Prophylactic Norfloxacin used to be considered effective in SBP prevention, but in recent years its efficacy has been partially compromised by increasing quinolone-resistant bacteria. However, whether the effects of alternative prophylactic regimens are superior to norfloxacin remains controversial. The goal of this study is to compare the effects of norfloxacin with other antibiotics in SBP prophylaxis for cirrhotic patients.

METHODS

We systematically searched Pubmed, Embase, and Cochrane Library Databases. Two reviewers independently identified relevant random control trials (RCTs) comparing the role of norfloxacin and other antibiotics in SBP prevention.

RESULTS

Eight studies comprising 1043 cirrhotic patients were included in this study. Norfloxacin and alternative antibiotics displayed comparable effects in SBP prophylaxis, survival benefit, overall infection prevention, and safety. Subgroup analyses revealed that rifaximin prophylaxis could reduce the recurrence of SBP with fewer adverse events but failed to improve overall survival compared with norfloxacin.

CONCLUSIONS

Other antibiotics are a reasonable alternative to norfloxacin in the prophylaxis of SBP. Rifaximin prophylaxis could be an alternative choose of antibiotic for SBP prevention because of its better protective effect and safety.

Primary prophylaxis for spontaneous bacterial peritonitis is linked to antibiotic resistance in the Veterans Health Administration

Spontaneous bacterial peritonitis (SBP) is a major cause of mortality. Although SBP primary prophylaxis (SBPPr) with fluoroquinolones and trimethoprim-sulfamethoxazole (TMP-SMX) is often used, resistance could reduce its benefit.

AIM

Analyze peritoneal fluid resistance patterns in patients with a first SBP episode with/without SBPPr using the Veterans Health Administration corporate data warehouse and to evaluate national antibiograms. Corporate data warehouse data were extracted using validated International Classification of Disease-9/10 codes, culture, resistance data, and outcomes of 7553 patients who developed their first inpatient SBP between 2009 and 2019 and compared between those with/without SBPPr. Escherichia coli ( E. coli ) and Klebsiella pneumoniae ( K. pneumoniae ) sensitivity to ciprofloxacin and TMP-SMX was calculated using 2021 Veterans Health Administration antibiogram data from all states. The most common isolates were E. coli , K. pneumoniae , and Staphylococcus species. Veterans taking ciprofloxacin SBBPr had higher fluoroquinolone resistance (34% vs 14% no SBPPr, p <0.0001); those taking TMP-SMX had higher TMP-SMX resistance (40% vs 14%, p <0.0001). SBPPr patients showed higher culture positivity, greater length of stay, higher second SBP, and higher probability of liver transplant rates versus no SBPPr. Multivariable models showed SBBPr to be the only variable associated with gram-negative resistance, and SBPPr was associated with a trend toward longer length of stay. E. coli ciprofloxacin sensitivity rates were 50%-87% and 43%-92% for TMP-SMX. K. pneumoniae ciprofloxacin sensitivity was 76%-100% and 72%-100% for TMP-SMX.

CONCLUSION

Among patients who developed their first SBP episode, there was a higher prevalence of antibiotic resistance in those on SBPPr, with a high rate of fluoroquinolone resistance across the Veterans Health Administration sites.

Response-Guided Therapy With Cefotaxime, Ceftriaxone, or Ciprofloxacin for Spontaneous Bacterial Peritonitis: A Randomized Trial: A Validation Study of 2021 AASLD Practice Guidance for SBP

INTRODUCTION

For the treatment of spontaneous bacterial peritonitis (SBP), cefotaxime, ceftriaxone, and ciprofloxacin were used as first-line agents. However, considering the increasing rate of antibiotic resistance, it is unclear which of these drugs can be initially recommended. This study aimed to compare the current efficacy of the 3 antibiotics, namely cefotaxime, ceftriaxone, and ciprofloxacin, for the treatment of SBP in patients with cirrhosis with ascites, when guided by therapeutic responses.

METHODS

This study was a multicenter, prospective, randomized controlled trial. The inclusion criteria were 16- to 75-year-old patients with liver cirrhosis with ascites, having polymorphonuclear cell count of >250/mm 3 . We performed a follow-up paracentesis at 48 hours to decide continuing or changing the assigned antibiotics and then assessed the resolution rates at 120 and 168 hours of treatment.

RESULTS

A total of 261 patients with cirrhosis who developed SBP were enrolled. Most of the patients were diagnosed as those with SBP within 48 hours of admission. The resolution rates at 120 hours, which is the primary endpoint, were 67.8%, 77.0%, and 73.6% in the cefotaxime, ceftriaxone, and ciprofloxacin groups, respectively ( P = 0.388), by intension-to-treat analysis. The 1-month mortality was similar among the groups ( P = 0.770). The model for end-stage liver disease score and the SBP resolution were significant factors for survival.

CONCLUSION

The efficacy of empirical antibiotics, such as cefotaxime, ceftriaxone, and ciprofloxacin, against SBP was not significantly different. In addition, these antibiotics administered based on response-guided therapy were still efficacious as initial treatment for SBP, especially in those with community-acquired infections.

Mastering Core Recommendations during HEPAtology ROUNDS in Patients with Advanced Chronic Liver Disease

Efficient and thorough care of hospitalized patients with advanced chronic liver disease is of utter importance to improve outcomes and optimize quality of life. This requires understanding current evidence and best practices. To facilitate focus on up-to-date knowledge and a practical approach, we have created the HEPA-ROUNDS mnemonic while outlining a practical review of the literature with critical appraisal for the busy clinician. The HEPA-ROUNDS mnemonic provides a structured approach that incorporates critical concepts in terms of prevention, management, and prognostication of the most common complications frequently encountered in patients with advanced chronic liver disease. In addition, implementing the HEPA-ROUNDS mnemonic can facilitate education for trainees and staff caring for patients with advanced chronic liver disease.

Early Diagnosis and Prevention of Infections in Cirrhosis

Strategies to prevent infection and improve outcomes in patients with cirrhosis. HAV, hepatitis A virus; HBV, hepatitis B virus; COVID-19, novel coronavirus disease 2019; NSBB, nonselective β-blocker; PPI, proton pump inhibitors.Cirrhosis is a risk factor for infections. Majority of hospital admissions in patients with cirrhosis are due to infections. Sepsis is an immunological response to an infectious process that leads to end-organ dysfunction and death. Preventing infections may avoid the downstream complications, and early diagnosis of infections may improve the outcomes. In this review, we discuss the pathogenesis, diagnosis, and biomarkers of infection; the incremental preventive strategies for infections and sepsi; and the consequent organ failures in cirrhosis. Strategies for primary prevention include reducing gut translocation by selective intestinal decontamination, avoiding unnecessary proton pump inhibitors' use, appropriate use of β-blockers, and vaccinations for viral diseases including novel coronavirus disease 2019. Secondary prevention includes early diagnosis and a timely and judicious use of antibiotics to prevent organ dysfunction. Organ failure support constitutes tertiary intervention in cirrhosis. In conclusion, infections in cirrhosis are potentially preventable with appropriate care strategies to then enable improved outcomes.

Evaluation of the current guidelines for antibacterial therapy strategies in patients with cirrhosis or liver failure

BACKGROUND

Bacterial infections are common complications in patients with cirrhosis or liver failure and are correlated with high mortality. Clinical practice guideline (CPG) is a reference used to help clinicians make decisions. This systematic appraisal aimed to evaluate the methodological quality and summarize the recommendations of reported CPGs in these patients.

METHODS

We systematically searched CPGs published from 2008 to 2019. The methodological quality of the included CPGs was assessed using the AGREE II instrument. We extracted and compared recommendations for prophylactic and empirical treatment strategies.

RESULTS

Fourteen CPGs with a median overall score of 56.3% were included. The highest domain score was Clarity of Presentation (domain 4, 85.4%), and the lowest was for Stakeholder Involvement (domain 2, 31.3%). Three CPGs had an overall score above 80%, and 6 CPGs had a score above 90% in domain 4. Prophylaxis should be strictly limited to patients with varicose bleeding, low ascites protein levels and a history of spontaneous bacterial peritonitis. Fluoroquinolones (norfloxacin and ciprofloxacin), third-generation cephalosporins (G3) (ceftriaxone and cefotaxime) and trimethoprim-sulfamethoxazole (SXT) are recommended for preventing infections in patients with cirrhosis or liver failure. G3, β-lactam/β-lactamase inhibitor combinations (BLBLIs) and carbapenems are recommended as the first choice in empirical treatment according to local epidemiology of bacterial resistance.

CONCLUSIONS

The methodological quality of CPGs focused on patients with cirrhosis or liver failure evaluated by the AGREE II instrument is generally poor. Three CPGs that were considered applicable without modification and 6 CPGs that scored above 90% in domain 4 should also be paid more attention to by healthcare practitioners. Regarding recommendations, norfloxacin, ciprofloxacin, ceftriaxone, cefotaxime, and SXT are recommended for prophylactic treatment appropriately. G3, BLBLIs, and carbapenems are recommended for use in empirical treatment strategies.

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.

Rifaximin Vs. Norfloxacin for Spontaneous Bacterial Peritonitis Prophylaxis: A Randomized Controlled Trial

Background

Spontaneous bacterial peritonitis (SBP) heralds increased mortality in cirrhosis, mandating strategies for prophylaxis. Norfloxacin has been the recommended choice for SBP prevention. However, its use has raised concerns about antibiotic resistance. Rifaximin has been suggested as an alternative. We investigated the efficacy of rifaximin against norfloxacin in primary and secondary prophylaxis of SBP.

Methods

In this open-labeled randomized trial, patients with either advanced cirrhosis having ascitic fluid protein levels (<1.5 g/l), Child-Pugh score ≥9 points, serum bilirubin ≥3 mg/dl or impaired renal function (primary prophylaxis group), or those with prior SBP (secondary prophylaxis group) received either norfloxacin (400 mg once daily) or rifaximin (550 mg twice daily). All patients were followed for six months, with the primary endpoint being the development of incident SBP.

Results

142 patients were assessed for eligibility, of which 132 met the enrolment criteria; 12 were lost to follow-up, while 4 discontinued treatment. In patients on primary prophylaxis, occurrence of SBP was similar (14.3% vs. 24.3%, P = 0.5), whereas in secondary prophylaxis SBP recurrence was lower with rifaximin (7% vs. 39% P = 0.004). Rifaximin significantly reduced the odds for SBP development in secondary prophylaxis [OR (95% CI0.14 (0.02-0.73; P = 0.02)]. Patients receiving rifaximin as secondary prophylaxis also had fewer episodes of hepatic encephalopathy (23.1% vs. 51.5%, P = 0.02). 180-day survival between the arms in either group was similar (P = 0.5, P = 0.2).

Conclusion

In comparison to norfloxacin, rifaximin significantly reduces incident events of SBP, as well as HE when used as a secondary prophylaxis, whereas for primary prophylaxis both have similar effects (NCT03695705).

Clinical trial registration

ClinicalTrials.gov number: NCT03695705.

One-year outcome of patients with cirrhosis who developed spontaneous bacterial empyema: A cohort study

OBJECTIVE

This study aimed to evaluate outcomes in cirrhotic patients diagnosed with spontaneous bacterial empyema (SBE) compared with those without this complication.

METHODS

We performed a retrospective cohort study of cirrhotic patients from a tertiary care center. The primary outcome was time to death or liver transplantation (LT) within one year after diagnosis of infection. We integrated three groups: patients with SBE (group A), patients with spontaneous bacterial peritonitis (SBP; group B), and cirrhotic patients without SBP or SBE (group C), matched by age, model for end-stage liver disease-sodium (MELD-Na) score and year of infection. Outcomes were analyzed using a Cox regression model adjusted for cardiovascular risk factors and MELD-Na score.

RESULTS

Between January 1999 and February 2019, 4829 cirrhotic patients were identified. Among them, 73 (1.5%) had hepatic hydrotorax, of whom 22 (30.1%) were diagnosed with SBE. Median age in group A was 58 years, 50% were men, and median MELD-Na was 21.5. Compared with group C, the hazard ratio of death or LT during the first year after infection was 2.98 (95% confidence interval [CI] 1.43-6.22, P = 0.004) for group A and 1.23 (95% CI 0.65-2.32, P = 0.522) for group B.

CONCLUSIONS

Our results suggest that patients with SBE have a worse outcome during the first year after infection is diagnosed. Patients who develop SBE should be promptly referred for transplant evaluation. SBE may emerge as new indication that could benefit from MELD exception points.

Antibiotic prophylaxis in patients with cirrhosis: Current evidence for clinical practice

Patients with cirrhosis show an increased susceptibility to infection due to disease-related immune-dysfunction. Bacterial infection therefore represents a common, often detrimental event in patients with advanced liver disease, since it can worsen portal hypertension and impair the function of hepatic and extra-hepatic organs. Among pharmacological strategies to prevent infection, antibiotic prophylaxis remains the first-choice, especially in high-risk groups, such as patients with acute variceal bleeding, low ascitic fluid proteins, and prior episodes of spontaneous bacterial peritonitis. Nevertheless, antibiotic prophylaxis has to deal with the changing bacterial epidemiology in cirrhosis, with increased rates of gram-positive bacteria and multidrug resistant rods, warnings about quinolones-related side effects, and low prescription adherence. Short-term antibiotic prophylaxis is applied in many other settings during hospitalization, such as before interventional or surgical procedures, but often without knowledge of local bacterial epidemiology and without strict adherence to antimicrobial stewardship. This paper offers a detailed overview on the application of antibiotic prophylaxis in cirrhosis, according to the current evidence.

Antibiotic prophylaxis for prevention of spontaneous bacterial peritonitis in liver cirrhosis: systematic review

BACKGROUND AND AIM

Spontaneous bacterial peritonitis is a potentially life-threatening infection in patients with liver cirrhosis and ascites. Its prevention is vital to improve prognosis of cirrhotic patients. The main objective of this systematic review was to evaluate what is the most efficacious and safest antibiotic prophylactic strategy.

METHODS

Studies were located by searching PubMed and Cochrane Central Register of Controlled Trials in The Cochrane Library until February 2019. Randomized controlled trials evaluating primary or secondary spontaneous bacterial peritonitis prophylaxis in cirrhotic patients with ascites were included. The selection of studies was performed in two stages: screening of titles and abstracts, and assessment of the full papers identified as relevant, considering the inclusion criteria. Data were extracted in a standardized way and synthesized qualitatively.

RESULTS

Fourteen studies were included. This systematic review demonstrated that daily norfloxacin is effective as a prophylactic antibiotic for the prevention of spontaneous bacterial peritonitis in patients with cirrhosis. Once weekly ciprofloxacin was not inferior to once daily norfloxacin, with good tolerance and no induced resistance. Trimethoprim-sulfamethoxazole and norfloxacin have similar efficacy for primary and secondary prophylaxis of spontaneous bacterial peritonitis, however, trimethoprim-sulfamethoxazole was associated with an increased risk of developing an adverse event. Rifaximin was more effective than norfloxacin in the secondary prophylaxis of spontaneous bacterial peritonitis, with a significant decrease in adverse events and mortality rate.

CONCLUSIONS

Continuous long-term selective intestinal decontamination with norfloxacin is the most widely used prophylactic strategy in spontaneous bacterial peritonitis, yet other equally effective and safe options are available.

Nitric oxide-inducing Genistein elicits apoptosis-like death via an intense SOS response in Escherichia coli

Increasing prevalence of multidrug-resistant untreatable infections has prompted researchers to trial alternative treatments such as a substitute for traditional antibiotics. This study endeavored to elucidate the antibacterial mechanism(s) of this isoflavone, via analysis of relationship between genistein and Escherichia coli. Furthermore, this investigation analyzed whether genistein generates nitric oxide (NO) in E. coli as NO contributes to cell death. RecA, an essential protein for the bacterial SOS response, was detected through western blot, and the activated caspases decreased without RecA. The results showed that the NO induced by genistein affected the bacterial DNA. Under conditions of acute DNA damage, an SOS response called apoptosis-like death occurred, affecting DNA repair. These results suggested that RecA was bacterial caspase-like protein. In addition, NO was toxic to the bacterial cells and induced dysfunction of the plasma membrane. Thus, membrane depolarization and phosphatidylserine exposure were observed similarly to eukaryotic apoptosis. In conclusion, the combined results demonstrated that the antibacterial mode of action(s) of genistein was a NO-induced apoptosis-like death, and the role of RecA suggested that it contributed to the SOS response of NO defense. KEY POINTS: • Genistein generates nitric oxide in E. coli. • Genistein exhibits intense SOS response in E. coli. • Genistein-induced NO causes apoptosis-like death in E. coli.

Systemic review and network meta-analysis: Prophylactic antibiotic therapy for spontaneous bacterial peritonitis

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is an important prognostic factor for outcomes in patients with cirrhosis. Antibiotic prophylaxis is recommended in patients at high risk for developing SBP, but the choice of antibiotics remains unclear.

AIM

To evaluate the efficacy of various antibiotics for prophylaxis of SBP based on randomized control trials (RCTs).

METHODS

Electronic databases were searched through November 2018 for RCTs evaluating the efficacy of therapies for primary or secondary prophylaxis of SBP. The primary outcome was the development of SBP. Sensitivity analyses limited to studies of primary or secondary prophylaxis and studies reported after 2010 were performed. The secondary outcome was the risk of all-cause mortality or transplant. The outcomes were assessed by rank of therapies based on network meta-analyses. Individual meta-analyses were also performed.

RESULTS

Thirteen RCTs (1742 patients) including norfloxacin, ciprofloxacin, rifaximin, trimethoprim-sulfamethoxazole (TMP-SMX), or placebo/no comparator were identified. Individual meta-analyses showed superiority of rifaximin over norfloxacin as well as norfloxacin and TMP-SMX over placebo. Network meta-analysis demonstrated the rank of efficacy in reducing the risk of SBP as: Rifaximin, ciprofloxacin, TMP-SMX, norfloxacin, and placebo/no comparator. Rifaximin ranked highest in sensitivity analyses limited to studies of primary or secondary prophylaxis and studies reported after 2010. Similarly, rifaximin ranked highest in reducing the risk of death/transplant.

CONCLUSION

The present comprehensive network meta-analysis provides RCT based evidence for superior efficacy of rifaximin compared to other antibiotics for the prophylaxis of SBP and reducing risk of death/transplant. Further RCTs are warranted to confirm our findings.

Antibiotics for prophylaxis of spontaneous bacterial peritonitis: systematic review & Bayesian network meta-analysis

BACKGROUND

Various antibiotic regimens are used for primary and secondary prevention of spontaneous bacterial peritonitis (SBP). A systematic review and network meta-analysis to compare various antibiotics regimens for primary and secondary prevention of SBP were done.

METHODS

We did a comprehensive literature search using various databases (i.e. MEDLINE via Ovid and PubMed, Embase, Cochrane Central Register of Controlled Trials and others) from inception to 26th October 2019 using various keywords. Only randomised studies which evaluated the role of antibiotics in adult cirrhotic patients with ascites for primary or secondary prophylaxis of SBP were included. The primary outcome was occurrence/recurrence of SBP episode and other outcomes assessed were extra-peritoneal infections and reduction in mortality. We did random-effects network meta-analysis using a Bayesian approach, and calculated odds ratios (ORs) and 95% credible intervals (CrI); agents were ranked using rank probabilities.

RESULTS

We found total 1701 records in our systematic database search and out of these 17 randomised trials were found eligible for network meta-analysis. For primary prevention of SBP, the odds ratio (95% CrI) for norfloxacin daily was 0.061 (0.0060, 0.33) and for rifaximin daily was 0.037 (0.00085, 0.87) and norfloxacin and rifaximin alternate month was 0.027 (0.00061, 0.61) when compared to placebo or no comparator. For the secondary prevention of SBP, rifaximin daily had odds of 0.022 (0.00011, 0.73).

CONCLUSION

Rifaximin is useful for both primary and secondary prevention of SBP whereas norfloxacin daily and alternate norfloxacin and rifaximin are useful for primary prophylaxis.

Antibiotic prophylaxis to prevent spontaneous bacterial peritonitis in people with liver cirrhosis: a network meta-analysis

BACKGROUND

Approximately 2.5% of all hospitalisations in people with liver cirrhosis are for spontaneous bacterial peritonitis. Spontaneous bacterial peritonitis is associated with significant short-term mortality; therefore, it is important to prevent spontaneous bacterial peritonitis in people at high risk of developing it. Antibiotic prophylaxis forms the mainstay preventive method, but this has to be balanced against the development of drug-resistant spontaneous bacterial peritonitis, which is difficult to treat, and other adverse events. Several different prophylactic antibiotic treatments are available; however, there is uncertainty surrounding their relative efficacy and optimal combination.

OBJECTIVES

To compare the benefits and harms of different prophylactic antibiotic treatments for prevention of spontaneous bacterial peritonitis in people with liver cirrhosis using a network meta-analysis and to generate rankings of the different prophylactic antibiotic treatments according to their safety and efficacy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and trials registers to November 2018 to identify randomised clinical trials in people with cirrhosis at risk of developing spontaneous bacterial peritonitis.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or status) in adults with cirrhosis undergoing prophylactic treatment to prevent spontaneous bacterial peritonitis. We excluded randomised clinical trials in which participants had previously undergone liver transplantation, or were receiving antibiotics for treatment of spontaneous bacterial peritonitis or other purposes.

DATA COLLECTION AND ANALYSIS

We performed a network meta-analysis with OpenBUGS using Bayesian methods and calculated the odds ratio, rate ratio, and hazard ratio (HR) with 95% credible intervals (CrI) based on an available-case analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance.

MAIN RESULTS

We included 29 randomised clinical trials (3896 participants; nine antibiotic regimens (ciprofloxacin, neomycin, norfloxacin, norfloxacin plus neomycin, norfloxacin plus rifaximin, rifaximin, rufloxacin, sparfloxacin, sulfamethoxazole plus trimethoprim), and 'no active intervention' in the review. Twenty-three trials (2587 participants) were included in one or more outcomes in the review. The trials that provided the information included people with cirrhosis due to varied aetiologies, with or without other features of decompensation, having ascites with low protein or previous history of spontaneous bacterial peritonitis. The follow-up in the trials ranged from 1 to 12 months. Many of the trials were at high risk of bias, and the overall certainty of evidence was low or very low. Overall, approximately 10% of trial participants developed spontaneous bacterial peritonitis and 15% of trial participants died. There was no evidence of differences between any of the antibiotics and no intervention in terms of mortality (very low certainty) or number of serious adverse events (very low certainty). However, because of the wide CrIs, clinically important differences in these outcomes cannot be ruled out. None of the trials reported health-related quality of life or the proportion of people with serious adverse events. There was no evidence of differences between any of the antibiotics and no intervention in terms of proportion of people with 'any adverse events' (very low certainty), liver transplantation (very low certainty), or the proportion of people who developed spontaneous bacterial peritonitis (very low certainty). The number of 'any' adverse events per participant was fewer with norfloxacin (rate ratio 0.74, 95% CrI 0.59 to 0.94; 4 trials, 546 participants; low certainty) and sulfamethoxazole plus trimethoprim (rate ratio 0.19, 95% CrI 0.02 to 0.81; 1 trial, 60 participants; low certainty) versus no active intervention. There was no evidence of differences between the other antibiotics and no intervention in the number of 'any' adverse events per participant (very low certainty). There were fewer other decompensation events with rifaximin versus no active intervention (rate ratio 0.61, 65% CrI 0.46 to 0.80; 3 trials, 575 participants; low certainty) and norfloxacin plus neomycin (rate ratio 0.06, 95% CrI 0.00 to 0.33; 1 trial, 22 participants; low certainty). There was no evidence of differences between the other antibiotics and no intervention in the number of decompensations events per participant (very low certainty). None of the trials reported health-related quality of life or development of symptomatic spontaneous bacterial peritonitis. One would expect some correlation between the above outcomes, with interventions demonstrating effectiveness across several outcomes. This was not the case. The possible reasons for this include sparse data and selective reporting bias, which makes the results unreliable. Therefore, one cannot draw any conclusions from these inconsistent differences based on sparse data. There was no evidence of any differences in the subgroup analyses (performed when possible) based on whether the prophylaxis was primary or secondary.

FUNDING

the source of funding for five trials were organisations who would benefit from the results of the study; six trials received no additional funding or were funded by neutral organisations; and the source of funding for the remaining 18 trials was unclear.

AUTHORS' CONCLUSIONS

Based on very low-certainty evidence, there is considerable uncertainty about whether antibiotic prophylaxis is beneficial, and if beneficial, which antibiotic prophylaxis is most beneficial in people with cirrhosis and ascites with low protein or history of spontaneous bacterial peritonitis. Future randomised clinical trials should be adequately powered, employ blinding, avoid postrandomisation dropouts (or perform intention-to-treat analysis), and use clinically important outcomes such as mortality, health-related quality of life, and decompensation events.

Primary and secondary prophylaxis of spontaneous bacterial peritonitis: current state of the art

Introduction: Spontaneous bacterial peritonitis represents a frequent and severe complication in cirrhotic patients with ascites. In daily practice, the diagnosis of spontaneous bacterial peritonitis might be challenging in the absence of the typical signs and symptoms of infection such as fever or leukocytosis. Areas covered: Aim of this review is to revise the current state of the art on primary and secondary spontaneous bacterial peritonitis. Literature search in Medline/Pubmed was performed. Expert opinion: Historically, gram-negative bacteria were the most frequent etiologic agents of spontaneous bacterial peritonitis, with Escherichia coli and Klebsiella spp. being the most frequently isolated bacteria. However, major changes in this regard occurred over the last few decades with an increasing prevalence of gram-positive, quinolone-resistant, and multidrug-resistant bacteria. In particular, the increasing prevalence of quinolone-resistant bacteria challenged the prominent role of norfloxacin in spontaneous bacterial peritonitis prevention. Given the high mortality rate and the risk of developing the hepatorenal syndrome, prophylaxis of spontaneous bacterial peritonitis is indicated in three high-risk populations: patients with acute gastrointestinal hemorrhage, patients with low total protein content in ascitic fluid and advanced cirrhosis, and patients with a previous history of spontaneous bacterial peritonitis (secondary prophylaxis).

Comparative efficacy of long-term antibiotic treatments in the primary prophylaxis of spontaneous bacterial peritonitis

BACKGROUND & AIMS

Several antibiotic treatments aiming to prevent spontaneous bacterial peritonitis (SBP) in cirrhotic patients with low-protein content in ascitic fluid have been tested; however, there are limited data on the comparative efficacy of these regimens. We assessed their comparative efficacy through a network meta-analysis and using GRADE criteria to appraise quality of evidence.

METHODS

Through literature review through October 2018, we identified 10 randomized controlled trials comparing antibiotic treatments (norfloxacin, ciprofloxacin, trimethoprim/sulfamethoxazole and rifaximin) with each other or placebo. Primary outcome was SBP occurrence, with mortality rate and rate of other infections as secondary outcomes.

RESULTS

In comparison with placebo, moderate quality evidence supports the use of norfloxacin and ciprofloxacin in primary prophylaxis of SBP (risk ratio 0.23; 95% CI, 0.09-0.56; P = 0.001 and 0.23; 0.07-0.79; P = 0.02 respectively) while only low quality evidence suggests superiority of rifaximin (risk ratio 0.15; 0.05-0.42). When antimicrobial agents were compared to each other, no significant difference was found. With regard to mortality, moderate quality supports the superiority of norfloxacin over placebo (risk ratio, 0.68; 95% CI, 0.47-0.99; P = 0.04), while ciprofloxacin and rifaximin showed only a non-significant benefit and no significant difference was found in the other comparisons. None of the tested antibiotics proved to significantly decrease the rate of other infections.

CONCLUSIONS

Norfloxacin appears to have significant benefit both in terms of SBP prevention and mortality; ciprofloxacin represents a valuable option although without a clear survival benefit. Rifaximin shows interesting results but needs to be tested in further trials.

Norfloxacin, ciprofloxacin, trimethoprim-sulfamethoxazole, and rifaximin for the prevention of spontaneous bacterial peritonitis: a network meta-analysis

For the prevention of spontaneous bacterial peritonitis (SBP) in cirrhotic patients with ascites, prophylactic antibiotics are recommended as a standard regimen. This study aimed to assess the efficacy of norfloxacin (N), ciprofloxacin (C), trimethoprim-sulfamethoxazole (T-S), and rifaximin (R) in the prevention of SBP. We searched the electronic databases including PubMed, Cochrane Library, Embase, and Web of Science from inception till 1 August 2018. The randomized-controlled trials that compared N, C, T-S, R, and placebo (P) were identified. A network meta-analysis (NMA) was carried out using the software STATA 14.0 and Revman 5.3. We included 16 studies involving 1984 participants in the NMA for SBP prevention. The NMA results showed that, compared with those treated with P (reference), patients treated with C, N, or R had a lower incidence of SBP and mortality. Similarly, the incidences of SBP and mortality for R were lower than those for N. The probabilities of ranking results showed that R ranked first with respect to the outcomes of the incidence of SBP and mortality. According to our results, R seemed to be the optimal regimen for protecting against SBP in patients with cirrhosis and ascites. However, considering the limitations of our study, additional high-quality studies are required in this respect.