Safety and Efficacy of Rifaximin in Prophylaxis of Spontaneous Bacterial Peritonitis: A Systematic Review and Meta-analysis

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.

Spontaneous bacterial peritonitis recurrence on norfloxacin secondary prophylaxis

BACKGROUND AND STUDY AIMS

Secondary prophylaxis with norfloxacin reduces recurrence of spontaneous bacterial peritonitis (SBP) significantly. No data available from Asia-Pacific region about recurrence of SBP in these patients.

PATIENTS AND METHODS

In a retrospective cohort study, we assessed recurrence rate of SBP in patients on norfloxacin secondary prophylaxis. One year recurrence of SBP, its profile, response rate and risk factors for recurrence were assessed.

RESULTS

A total of 112 patients were analysed. During first episode of SBP, culture positive rate was 39/112(34.8 %) and resistance to ceftriaxone was 51.2 %. Overall efficacy of ceftriaxone as first line antibiotic was 70.5 % (70/112), but only 49 % (19/39) among culture positive patients. E. coli is the commonest organism isolated (21/39, 53.8 %), MDR organism in 12.8 % (5/39). Cumulative incidence of SPB recurrence was 22.3 % (25/112) on norfloxacin secondary prophylaxis at 1 year. Culture positive rate in recurrent SBP was 48 % (12/25) and ceftriaxone resistance and MDR organism were seen in 66.6 % and 16.6 %. Overall response rate to ceftriaxone in recurrent SBP was 40 % (10/25) and 21 % (3/14) in culture positive patients. Risk factors for SBP recurrence were age, INR and albumin (p < 0.05). No increase cumulative incidence of death among patients with or without recurrence.

CONCLUSION

Despite recent changes in bacteriological profile in SBP, recurrence of SBP on norfloxacin prophylaxis remains low. In recurrent SBP, response to ceftriaxone is significantly lower than first episode and there is trend towards increase in MDR organism in culture positive patient receiving norfloxacin.

Expert consensus on the diagnosis and treatment of end-stage liver disease complicated by infections

End-stage liver disease (ESLD) is a life-threatening clinical syndrome and when complicated with infection the mortality is markedly increased. In patients with ESLD, bacterial or fungal infection can induce or aggravate the occurrence or progression of liver decompensation. Consequently, infections are among the most common complications of disease deterioration. There is an overwhelming need for standardized protocols for early diagnosis and appropriate management for patients with ESLD complicated by infections. Asia Pacific region has the largest number of ESLD patients, due to hepatitis B and the growing population of alcohol and NAFLD. Concomitant infections not only add to organ failure and high mortality but also to financial and healthcare burdens. This consensus document assembled up-to-date knowledge and experience from colleagues across the Asia-Pacific region, providing data on the principles as well as evidence-based current working protocols and practices for the diagnosis and treatment of patients with ESLD complicated by infections.

Impact of rifaximin use in infections and mortality in patients with decompensated cirrhosis and hepatic encephalopathy

INTRODUCTION

Infections in patients with cirrhosis are associated with high morbidity and mortality. Rifaximin is an antibiotic used to treat and prevent hepatic encephalopathy (HE); however, it has been suggested that it may play a crucial role in reducing infections in these populations.

AIM

To evaluate the role of rifaximin in preventing frequent cirrhosis-related infections [spontaneous bacterial peritonitis, pneumonia, urinary tract infection (UTI), and bacteremia], Clostridioides difficile infection, and all-cause mortality, as well as determining adverse effects and adherence to the drug.

METHODS

A retrospective cohort study was conducted on decompensated cirrhotic patients with history of HE between January 2017 and November 2022 at a university center. Patients with cirrhosis, regardless of their etiology and severity, were included in the study, encompassing both hospitalized and outpatient cases. The statistical analysis included adjusted general linear models, Poisson regressions, and propensity score matching.

RESULTS

We included 153 patients. The mean age in the cohort was 60.2 ± 12.3 years and 67 (43.8%) were women. The main cause of cirrhosis was metabolic dysfunction-associated steatotic liver disease 52 (38%), and the median Model of End-Stage Liver Disease sodium was 16.5 (7-32). In the cohort, 65 (45%) patients used rifaximin. The mean follow-up was 32 months. Eighty-five patients with infectious events were recorded, and a total of 164 infectious events were registered. The main infectious events were UTIs (62, 37.8%) and pneumonia (38, 23.2%). The use of rifaximin was associated with lower infection rates, displaying an incidence rate ratio (IRR) of 0.64 [95% confidence interval (CI) (0.47-0.89); p = 0.008]. However, no discernible impact on mortality outcome was observed [IRR 1.9, 95% CI (0.9-4.0); p = 0.09]. There were no reported adverse effects, and no patient discontinued the therapy due to adverse effects.

CONCLUSION

The use of rifaximin significantly reduces infections in patients with cirrhosis and HE. Despite rifaximin was associated with a decreased all-cause mortality, this impact was not statistically significant in the adjusted analysis.

A Comprehensive Systematic Review of the Latest Management Strategies for Hepatorenal Syndrome: A Complicated Syndrome to Tackle

Hepatorenal syndrome (HRS), defined by the extreme manifestation of renal impairment in patients with cirrhosis, is characterized by reduced renal blood flow and glomerular filtration rate. It is diagnosed with reduced kidney function confirming the absence of intrinsic kidney disease, such as hematuria or proteinuria. HRS is potentially reversible with liver transplantation or vasoconstrictor drugs. The condition carries a poor prognosis with high mortality rates, particularly in patients with advanced cirrhosis. The latest management for HRS involves a combination of pharmacological and non-pharmacological interventions, aiming to improve renal function and reduce the risk of mortality. Pharmacological treatments include vasoconstrictors, such as terlipressin and midodrine, and albumin infusion, which have been shown to improve renal function and reduce mortality in HRS patients. Non-pharmacological interventions, including invasive procedures such as transjugular intrahepatic portosystemic shunt (TIPS), plasma exchange, liver transplantation, and renal replacement therapy, may also be considered. Though TIPS has been shown to be effective in improving renal function in HRS patients, liver transplantation remains at the top of the consideration for the treatment of end-stage liver disease and HRS. Recent studies have placed importance on early recognition and prompt intervention in HRS patients, as delaying treatment can result in poorer outcomes. Although there are numerous reviews that summarize various aspects of HRS, the recent advancements in the management and pathophysiology of HRS are still insufficient. Therefore, in this review, we summarized a brief pathophysiology and highlighted recent advancements in the management of HRS with a quick review of the latest articles.

Rifaximin for prevention and treatment of hepatic encephalopathy in people with cirrhosis

BACKGROUND

Hepatic encephalopathy describes the spectrum of neuropsychiatric changes that may complicate the course of cirrhosis and detrimentally affect outcomes. Ammonia plays a key role in its development. Rifaximin is a non-absorbable antibiotic that inhibits urease-producing bacteria and reduces absorption of dietary and bacterial ammonia.

OBJECTIVES

To evaluate the beneficial and harmful effects of rifaximin versus placebo, no intervention, or non-absorbable disaccharides for: (i) the prevention of hepatic encephalopathy, and (ii) the treatment of minimal and overt hepatic encephalopathy, in people with cirrhosis, both when used alone and when combined with a non-absorbable disaccharide.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Clinical Trials Register, CENTRAL, MEDLINE, Embase, three other databases, the reference lists of identified papers, and relevant conference proceedings. We wrote to authors and pharmaceutical companies for information on other published, unpublished, or ongoing trials. Searches were performed to January 2023.

SELECTION CRITERIA

We included randomised clinical trials assessing prevention or treatment of hepatic encephalopathy with rifaximin alone, or with a non-absorbable disaccharide, versus placebo/no intervention, or a non-absorbable disaccharide alone.

DATA COLLECTION AND ANALYSIS

Six authors independently searched for studies, extracted data, and validated findings. We assessed the design, bias risk, and participant/intervention characteristics of the included studies. We assessed mortality, serious adverse events, health-related quality of life, hepatic encephalopathy, non-serious adverse events, blood ammonia, Number Connection Test-A, and length of hospital stay.

MAIN RESULTS

We included 41 trials involving 4545 people with, or at risk for, developing hepatic encephalopathy. We excluded 89 trials and identified 13 ongoing studies. Some trials involved participants with more than one type of hepatic encephalopathy or more than one treatment comparison. Hepatic encephalopathy was classed as acute (13 trials), chronic (7 trials), or minimal (8 trials), or else participants were considered at risk for its development (13 trials). The control groups received placebo (12 trials), no/standard treatment (1 trial), or a non-absorbable disaccharide (14 trials). Eighteen trials assessed rifaximin plus a non-absorbable disaccharide versus a non-absorbable disaccharide alone. We classified 11 trials as at high risk of overall bias for mortality and 28 for non-mortality outcomes, mainly due to lack of blinding, incomplete outcome data, and selective reporting. Compared to placebo/no intervention, rifaximin likely has no overall effect on mortality (risk ratio (RR) 0.83, 95% confidence interval (CI) 0.50 to 1.38; P = 48, I2 = 0%; 13 trials, 1007 participants; moderate-certainty evidence), and there may be no overall effect when compared to non-absorbable disaccharides (RR 0.99, 95% CI 0.49 to 1.97; P = 0.97, I2 = 0%; 10 trials, 786 participants; low-certainty evidence). However, there is likely a reduction in the overall risk of mortality when comparing rifaximin plus a non-absorbable disaccharide to a non-absorbable disaccharide alone (RR 0.69, 95% CI 0.55 to 0.86; number needed to treat for an additional beneficial outcome (NNTB) = 22; P = 0.001, I2 = 0%; 14 trials, 1946 participants; moderate-certainty evidence). There is likely no effect on the overall risk of serious adverse events when comparing rifaximin to placebo/no intervention (RR 1.05, 95% CI 0.83 to 1.32; P = 68, I2 = 0%; 9 trials, 801 participants; moderate-certainty evidence) and there may be no overall effect when compared to non-absorbable disaccharides (RR 0.97, 95% CI 0.66 to 1.40; P = 85, I2 = 0%; 8 trials, 681 participants; low-certainty evidence). However, there was very low-certainty evidence that use of rifaximin plus a non-absorbable disaccharide may be associated with a lower risk of serious adverse events than use of a non-absorbable disaccharide alone (RR 0.66, 95% CI 0.45 to 0.98; P = 0.04, I2 = 60%; 7 trials, 1076 participants). Rifaximin likely results in an overall effect on health-related quality of life when compared to placebo/no intervention (mean difference (MD) -1.43, 95% CI -2.87 to 0.02; P = 0.05, I2 = 81%; 4 trials, 214 participants; moderate-certainty evidence), and may benefit health-related quality of life in people with minimal hepatic encephalopathy (MD -2.07, 95% CI -2.79 to -1.35; P < 0.001, I2 = 0%; 3 trials, 176 participants). The overall effect on health-related quality of life when comparing rifaximin to non-absorbable disaccharides is very uncertain (MD -0.33, 95% CI -1.65 to 0.98; P = 0.62, I2 = 0%; 2 trials, 249 participants; very low-certainty evidence). None of the combined rifaximin/non-absorbable disaccharide trials reported on this outcome. There is likely an overall beneficial effect on hepatic encephalopathy when comparing rifaximin to placebo/no intervention (RR 0.56, 95% CI 0.42 to 0.77; NNTB = 5; P < 0.001, I2 = 68%; 13 trials, 1009 participants; moderate-certainty evidence). This effect may be more marked in people with minimal hepatic encephalopathy (RR 0.40, 95% CI 0.31 to 0.52; NNTB = 3; P < 0.001, I2 = 10%; 6 trials, 364 participants) and in prevention trials (RR 0.71, 95% CI 0.56 to 0.91; NNTB = 10; P = 0.007, I2 = 36%; 4 trials, 474 participants). There may be little overall effect on hepatic encephalopathy when comparing rifaximin to non-absorbable disaccharides (RR 0.85, 95% CI 0.69 to 1.05; P = 0.13, I2 = 0%; 13 trials, 921 participants; low-certainty evidence). However, there may be an overall beneficial effect on hepatic encephalopathy when comparing rifaximin plus a non-absorbable disaccharide to a non-absorbable disaccharide alone (RR 0.58, 95% CI 0.48 to 0.71; NNTB = 5; P < 0.001, I2 = 62%; 17 trials, 2332 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Compared to placebo/no intervention, rifaximin likely improves health-related quality of life in people with minimal hepatic encephalopathy, and may improve hepatic encephalopathy, particularly in populations with minimal hepatic encephalopathy and when it is used for prevention. Rifaximin likely has no overall effect on mortality, serious adverse events, health-related quality of life, or hepatic encephalopathy compared to non-absorbable disaccharides. However, when used in combination with a non-absorbable disaccharide, it likely reduces overall mortality risk, the risk of serious adverse events, improves hepatic encephalopathy, reduces the length of hospital stay, and prevents the occurrence/recurrence of hepatic encephalopathy. The certainty of evidence for these outcomes is very low to moderate; further high-quality trials are needed.

Gut Microbiota and Antibiotic Treatments for the Main Non-Oncologic Hepato-Biliary-Pancreatic Disorders

The gut microbiota is a pivotal actor in the maintenance of the balance in the complex interconnections of hepato-biliary-pancreatic system. It has both metabolic and immunologic functions, with an influence on the homeostasis of the whole organism and on the pathogenesis of a wide range of diseases, from non-neoplastic ones to tumorigenesis. The continuous bidirectional metabolic communication between gut and hepato-pancreatic district, through bile ducts and portal vein, leads to a continuous interaction with translocated bacteria and their products. Chronic liver disease and pancreatic disorders can lead to reduced intestinal motility, decreased bile acid synthesis and intestinal immune dysfunction, determining a compositional and functional imbalance in gut microbiota (dysbiosis), with potentially harmful consequences on the host's health. The modulation of the gut microbiota by antibiotics represents a pioneering challenge with striking future therapeutic opportunities, even in non-infectious diseases. In this setting, antibiotics are aimed at harmonizing gut microbial function and, sometimes, composition. A more targeted and specific approach should be the goal to pursue in the future, tailoring the treatment according to the type of microbiota modulation to be achieved and using combined strategies.

Hepatorenal Syndrome: Definitions, Diagnosis, and Management

Hepatorenal syndrome (HRS) is a hemodynamically driven process mediated by renal dysregulation and inflammatory response. Albumin, antibiotics, and β-blockers are among therapies that have been studied in HRS prevention. There are no Food and Drug Administration-approved treatments for HRS although multiple liver societies have recommended terlipressin as first-line pharmacotherapy. Renal replacement therapy is the primary modality used to bridge to definitive therapy with orthotopic liver transplant or simultaneous liver-kidney transplant. Advances in our understanding of HRS pathophysiology and emerging therapeutic modalities are needed to change outcomes for this vulnerable population.

Rifaximin-α reduces gut-derived inflammation and mucin degradation in cirrhosis and encephalopathy: RIFSYS randomised controlled trial

BACKGROUND & AIMS

Rifaximin-α is efficacious for the prevention of recurrent hepatic encephalopathy (HE), but its mechanism of action remains unclear. We postulated that rifaximin-α reduces gut microbiota-derived endotoxemia and systemic inflammation, a known driver of HE.

METHODS

In a placebo-controlled, double-blind, mechanistic study, 38 patients with cirrhosis and HE were randomised 1:1 to receive either rifaximin-α (550 mg BID) or placebo for 90 days.

PRIMARY OUTCOME

50% reduction in neutrophil oxidative burst (OB) at 30 days.

SECONDARY OUTCOMES

changes in psychometric hepatic encephalopathy score (PHES) and neurocognitive functioning, shotgun metagenomic sequencing of saliva and faeces, plasma and faecal metabolic profiling, whole blood bacterial DNA quantification, neutrophil toll-like receptor (TLR)-2/4/9 expression and plasma/faecal cytokine analysis.

RESULTS

Patients were well-matched: median MELD (11 rifaximin-α vs. 10 placebo). Rifaximin-α did not lead to a 50% reduction in spontaneous neutrophil OB at 30 days compared to baseline (p = 0.48). However, HE grade normalised (p = 0.014) and PHES improved (p = 0.009) after 30 days on rifaximin-α. Rifaximin-α reduced circulating neutrophil TLR-4 expression on day 30 (p = 0.021) and plasma tumour necrosis factor-α (TNF-α) (p <0.001). Rifaximin-α suppressed oralisation of the gut, reducing levels of mucin-degrading sialidase-rich species, Streptococcus spp, Veillonella atypica and parvula, Akkermansia and Hungatella. Rifaximin-α promoted a TNF-α- and interleukin-17E-enriched intestinal microenvironment, augmenting antibacterial responses to invading pathobionts and promoting gut barrier repair. Those on rifaximin-α were less likely to develop infection (odds ratio 0.21; 95% CI 0.05-0.96).

CONCLUSION

Rifaximin-α led to resolution of overt and covert HE, reduced the likelihood of infection, reduced oralisation of the gut and attenuated systemic inflammation. Rifaximin-α plays a role in gut barrier repair, which could be the mechanism by which it ameliorates bacterial translocation and systemic endotoxemia in cirrhosis.

CLINICAL TRIAL NUMBER

ClinicalTrials.gov NCT02019784.

LAY SUMMARY

In this clinical trial, we examined the underlying mechanism of action of an antibiotic called rifaximin-α which has been shown to be an effective treatment for a complication of chronic liver disease which effects the brain (termed encephalopathy). We show that rifaximin-α suppresses gut bacteria that translocate from the mouth to the intestine and cause the intestinal wall to become leaky by breaking down the protective mucus barrier. This suppression resolves encephalopathy and reduces inflammation in the blood, preventing the development of infection.

D, Hassan AS, Zahran FE, Abdelghany RS, Siddik RI, Abdel-Hamed AR. The Role of MicroRNAs (miRNA 155, miRNA-146b) and Procalcitonin as Novel Markers for the Diagnosis of Spontaneous Bacterial Peritonitis

Background:

MircoRNAs are endogenous, small non-coding RNA molecules that have been recognized as important modulators of gene expression. MicroRNA is considered one of the potential biomarkers of infection and inflammation. Our study aims to identify the potential role of miRNA-155, miRNA-146b, and Procalcitonin (PCT) in the early detection of spontaneous bacterial peritonitis in cirrhotic liver patients. miRNA-155 and 146b are molecular biomarkers , while procalcitonin is a serum marker in ascites patients complicated with Spontaneous Bacterial Peritonitis (SBP) .

Methods:

This study was conducted on 199 patients, 101 of them have ascites complicated with spontaneous bacterial peritonitis, and 98 patients without spontaneous bacterial peritonitis (control group). Ascitic fluid samples were collected from patients with SBP undergoing paracentesis at National Hepatology Institute in Egypt. MicroRNAs were determined in the serum using qPCR (quantitative polymerase chain reaction), while procalcitonin has been assessed in serum samples using ELISA (Enzyme-linked immune assay) technique.

Results:

Serum levels of miRNA-146b & miRNA-155 were significantly higher (p<0.001) in spontaneous bacterial peritonitis patients (79.2% and 97.0% respectively) than ascites patients (17.3% and 7.1%, respectively). Furthermore, the serum level of procalcitonin was significantly higher (p<0.001) in spontaneous bacterial peritonitis patients than that in ascites patients (68.3% and 27.6%, respectively).

Conclusion:

miRNA-155, miRNA-146b and procalcitonin can be used as early markers for the detection of SBP in hepatic patients with ascites.

Bacterial Infections in Cirrhotic Patients in a Tertiary Care Hospital

BACKGROUND AND AIMS

Patients with cirrhosis are immunocompromised and at higher risk of developing infections compared to the general population. The aim of this study was to assess the incidence of infections in cirrhotic patients in a large academic liver center and investigate potential associations between infections, bacteria isolated, therapeutic regimens used, and mortality.

METHODS

This was a retrospective chart review study, including 192 patients. All patients had a diagnosis of cirrhosis and were admitted to University Hospital. Information collected included demographics, etiology of cirrhosis, identification of bacteria from cultures, multidrug-resistant (MDR) status, antibiotics administered, intensive care unit (ICU) admission, and patient mortality.

RESULTS

Infections were present in 105 (54.6%) patients, and 60 (31.2%) patients had multiple infections during a hospitalization(s) for infections. A total of 201 infections were identified. Urinary tract infections (UTIs) were the most common infection (37.8%), followed by bacteremia (20.4%), pneumonia (12.9%), spontaneous bacterial peritonitis (SBP) (11.9%), abscess/cellulitis (6.0%), infectious diarrhea (6.0%), and other (5.0%). Escherichia coli was the most common bacteria isolated (13.4%), both among sensitive and MDR infections. MDR bacteria were the cause for 41.3% of all infections isolated. Fungi accounted for 9.5% of infections. 21.9% of patients had decompensation from their infection(s) that required ICU care, and 14.6% of patients died during hospitalization or soon after discharge.

CONCLUSIONS

The incidence of infections in cirrhotic patients is much higher than in their non-cirrhotic counterparts (54.6%), even higher than prior studies suggest. As many of these infections are caused by MDR bacteria and fungal organisms, stronger empiric antibiotics and antifungals should be considered when initially treating this immunocompromised population. However, once organism sensitivities are discovered, narrowing of antibiotic regimens must occur to maintain good antibiotic stewardship.

Predictive and Prognostic Value of Ascitic Fluid Mannose Binding Lectin in Patients with Spontaneous Bacterial Peritonitis

BACKGROUND

Spontaneous bacterial peritonitis is a common bacterial infection of ascitic fluid, mainly in ascites due to liver cirrhosis. Mannose-binding lectin (MBL) can activate phagocytosis and the complement system. Spontaneous bacterial peritonitis was detected to be higher in MBL deficiency. This study aimed to assess ascitic fluid MBL in liver cirrhosis and spontaneous bacterial peritonitis.

METHODS

Ninety patients with cirrhotic ascites were included. Forty five of them had SBP. Child- Pugh score, Model for End Stage Liver Disease (MELD) and its update (uMELD) scores were used to assess the severity of liver cirrhosis. Ascitic fluid samples were obtained for differentiation of leucocytic count, estimation of albumin, protein, glucose, and serum-ascitic albumin gradient. Ascitic fluid levels of MBL were measured for all patients. SBP was documented if polymorphonuclear leucocytic count ≥250/mm in ascitic fluid.

RESULTS

Ascitic fluid MBL level was significantly lower in patients with SBP. MBL had a significant negative correlation with ascitic total leukocytic count (TLC), also with serum creatinine, bilirubin, PT, INR and MELD score among SBP patients. However, it had a significant positive correlation with ascitic protein and with platelets. According to multivariate analysis, fever, TLC, platelets, creatinine, MBL, glucose and polymorphs were independent predictors for SBP development.

CONCLUSION

Ascitic fluid MBL could be a good predictive and prognostic marker in patients with cirrhosis and spontaneous bacterial peritonitis.

Gut Microbiota, Peroxisome Proliferator-Activated Receptors, and Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world. HCC incidence rate is sixth and mortality is fourth worldwide. However, HCC pathogenesis and molecular mechanisms remain unclear. The incidence of HCC is associated with genetic, environmental, and metabolic factors. The role of gut microbiota in the pathogenesis of HCC has attracted researchers' attention because of anatomical and functional interactions between liver and intestine. Studies have demonstrated the involvement of gut microbiota in the development of HCC and chronic liver diseases, such as alcoholic liver disease (ALD), nonalcoholic fatty liver disease (NAFLD), and liver cirrhosis. Peroxisome proliferator-activated receptors (PPARs) are a group of receptors with diverse biological functions. Natural and synthetic PPAR agonists show potential for treatment of NAFLD, liver fibrosis, and HCC. Recent studies have demonstrated that PPARs take part in gut microbiota inhabitation and adaptation. This manuscript reviews the role of gut microbiota in the development of HCC and precancerous diseases, the role of PPARs in modulation of gut microbiota and HCC, and potential of gut microbiota for HCC diagnosis and treatment.

Amyloid A in Serum and Ascitic Fluid as a Novel Diagnostic Marker of Spontaneous Bacterial Peritonitis

BACKGROUND

Diagnosis of Spontaneous Bacterial Peritonitis (SBP) depends mainly on ascetic fluid culture which may be negative in spite of the clinical suggestion of SBP and high ascetic fluid neutrophilic count.

AIMS

This study aimed to evaluate the biological importance of amyloid A biomarker in both serum and ascetic fluid to diagnose SBP as early as possible and to compare it to other markers (C-reactive protein (CRP), and the neutrophil-to-lymphocyte ratio (NLR)).

METHODS

This study included 37 patients with hepatic ascites; twenty-two of them had SBP, and 15 patients did not have SBP. Serum and ascetic fluid amyloid A, ascetic fluid neutrophil, C-reactive protein, and neutrophil-to-lymphocyte ratio were measured in all subjects before the start of antimicrobial chemotherapy to the infected ones.

RESULTS

Both the serum and ascetic fluid amyloid and also, CRP were significantly higher in patients infected with ascetic fluid than others. The cut-off point of serum amyloid A for early detection of SBP was 9.25ug/ml with the high sensitivity and specificity. For ascetic amyloid A, the sensitivity and specificity were 90.09% and 60% at cut-off point 2.85ug/ml, respectively.

CONCLUSION

Amyloid A in serum and ascitic fluid can be considered as a good biomarker for early diagnosis of SBP.

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.