Bacteremia in Patients With Liver Cirrhosis: Prevalence and Predictors of Multidrug Resistant Organisms

A Case of Complicated Bacteremia: When the Source Is in the Blood

Infective endocarditis is an infectious disease of the heart tissue, mainly affecting heart valves and intracardiac devices. We present the case of a 71-year-old male pacemaker carrier with a history of hepatic cirrhosis, esophageal varices, hepatocellular carcinoma, and severe aortic stenosis, who was admitted to the emergency room and hospitalized due to upper gastrointestinal bleeding. Although upper endoscopy showed no signs of active acute hemorrhage, the patient required a red blood cell transfusion. Upon admission, elevated inflammatory parameters prompted the initiation of empirical therapy with ceftriaxone. Although urinalysis, chest X-ray, thoracoabdominopelvic computed tomography, and transthoracic echocardiogram weren't suggestive of infection, an Enterococcus faecium was isolated in blood cultures. Following an antibiotic switch to daptomycin, based on susceptibility testing, and the patient's hemodynamic stability, he was transferred to a home hospitalization unit for continued care. Despite good clinical and analytical progress, the patient's history of aortic valve stenosis and pacemaker, along with persistently positive blood cultures despite antibiotic therapy and sustained fever, raised a high level of clinical suspicion. This led to the decision to perform a new echocardiogram, which revealed several aortic valve vegetations, allowing the diagnosis of infective endocarditis. Following a multidisciplinary discussion, and in accordance with antibiotic susceptibility tests, linezolid was initiated. After 40 days, although the echocardiogram was still suggestive of aortic valve infiltration due to an infectious process, hemodynamic stability, sustained apyrexia, and sterile blood cultures allowed for a possible discharge on oral therapy with moxifloxacin and rifampicin. Although this is a case of infective endocarditis in a high-risk patient, the chronology is unusual, as endocarditis was not detected in the initial echocardiogram. The diagnosis was only possible after weeks of persistent positive blood cultures, thanks to the medical team's high level of suspicion, which led them to insist on repeating the echocardiogram. In fact, the diagnosis of infective endocarditis remains a challenge to this day. This case highlights the importance of recognizing risk factors and pursuing the diagnosis when clinical suspicion persists, including repeating imaging when necessary to ensure timely diagnosis and appropriate management.

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.

Bloodstream Infections Caused by Multidrug Resistant Bacteria: Clinical and Microbiological Features and Mortality

Objectives

Bloodstream infections (BSI) are associated with high morbidity and mortality. The aim of our study is to determine whether there is a relationship between certain risk factors such as the underlying disease, patient's medical history, or interventional procedures and multidrug resistant (MDR) bacterial infection and to determine the risk factors for mortality.

Methods

Two hundred and twenty-two outpatients and inpatients who were diagnosed with bacteremia over a 6-month period were included in the study. 232 agents from 222 patients were isolated and tested for antimicrobial susceptibility. The relationship between patients demographic and clinical data and MDR was analyzed.

Results

The most common microorganisms were Gram-negative bacteria (59.4%), Gram-positive bacteria (36.9%), Candida species (2.2%), and anaerobic bacteria (1.35%). The most common isolates were Escherichia coli 53 (22.8%), Staphylococcus aureus 35 (%15.1), Klebsiella pneumoniae 26 (11.2%), Pseudomonas spp. (n=17, 7.3%), Acinetobacter spp 17 (7.3%), and Enterococcus spp 14 (6%). Microorganisms with the highest antimicrobial resistance observed were 82.3% in Acinetobacter baumannii, 64.5% in coagulase-negative staphylococci, 60.3% in E. coli, 50% in K. pneumoniae, and 27.2% in Enterobacterales spp. Most patients with BSI caused by MDR bacteria were in the intensive care unit (64%). Sepsis diagnosis, urinary catheter use, history of surgery, and use of broad-spectrum antibiotics as well as risk factors for antibiotic-resistant bacteremia, coronary artery disease, inappropriate empirical therapy, healthcare-associated infections, urinary catheterization, and stay in the ICU were determined as risk factors for mortality.

Conclusion

Our study identified the risk factors of BSI caused by MDR bacteria and helped to reveal the relationship between these factors and mortality.

Vaccination in Chronic Liver Disease: An Update

Patients with chronic liver disease (CLD) with or without cirrhosis remain at risk of developing hepatic decompensation when infected with viral or bacterial pathogens. The Advisory Committee on Immunization Practices (ACIP) currently recommends vaccination in CLD against hepatitis A virus (HAV), hepatitis B virus (HBV), influenza, pneumococcus, herpes zoster, tetanus, diphtheria, pertussis, and SARS-CoV-2. Inactivated vaccines are preferred over live attenuated ones, especially in transplant recipients where live vaccines are contraindicated. As the severity of the liver disease progresses, vaccine efficacy declines, and therefore, vaccines should be ideally administered early in the disease course for optimal immune response. Despite the strong recommendations, overall vaccination coverage in CLD remains poor; however, it is encouraging to note that in recent years coverage against influenza and pneumococcus has shown some improvement. Inadequate access to healthcare, lack of information on vaccine safety, poor financial reimbursement for healthcare providers, and vaccine misinformation are often responsible for low immunization rates. This review summarizes the impact of vaccine-preventable illness in those with CLD, updated vaccine guidelines, seroconversion rates in the vaccinated, and barriers faced by healthcare professionals in immunizing those with liver disease.

Variable Normalization of Naïve CD4+ Lymphopenia and Markers of Monocyte and T Cell Activation over the Course of Direct-Acting Anti-Viral Treatment of Chronic Hepatitis C Virus Infection

Chronic hepatitis C virus (HCV) infection is associated with naïve CD4+ T cell lymphopenia and long-standing/persistent elevation of cellular and soluble immune activation parameters, the latter heightened in the setting of HIV co-infection. The underlying mechanisms are not completely understood. However, we recently reported that accelerated peripheral cell death may contribute to naïve CD4+ T cell loss and that mechanistic relationships between monocyte activation, T cell activation, and soluble inflammatory mediators may also contribute. Chronic HCV infection can be cured by direct-acting anti-viral (DAA) therapy, and success is defined as sustained virological response (SVR, undetectable HCV RNA (ribonucleic acid) at 12 weeks after DAA treatment completion). However, there is no general consensus on the short-term and long-term immunological outcomes of DAA therapy. Here, we consolidate previous reports on the partial normalization of naïve CD4+ lymphopenia and T cell immune activation and the apparent irreversibility of monocyte activation following DAA therapy in HCV infected and HCV/HIV co-infected individuals. Further, advanced age and cirrhosis are associated with delayed or abrogation of immune reconstitution after DAA therapy, an indication that non-viral factors also likely contribute to host immune dysregulation in HCV infection.

Bacteraemia, sepsis and antibiotic resistance in Australian patients with cirrhosis: a population-based study

Objective

Multiple factors predispose patients with cirrhosis to sepsis and/or bacteraemia and this has a high mortality rate. Within different geographical regions there are marked differences in the prevalence of infection with multidrug-resistant organisms (MDR). This study examined risk factors for and outcomes of sepsis/bacteraemia in public hospital admissions with cirrhosis in the state of Queensland, Australia, over the last decade, along with the bacterial pathogens responsible and their antibiotic susceptibility profiles.

Design

A population-based retrospective cohort study of public hospital admissions was conducted from 1 January 2008 to 31 December 2017. Hospital admissions for patients with a diagnosis of cirrhosis were categorised by the presence or absence of sepsis/bacteraemia. Clinical and sociodemographic information including cirrhosis aetiology, complications and comorbidities, and in-hospital mortality were examined using bivariate and multivariate analyses. In patients with bacteraemia, the type and prevalence of bacteria and antibiotic resistance was assessed.

Results

Sepsis/bacteraemia was present in 3951 of 103 165 hospital admissions with a diagnosis of cirrhosis. Factors associated with sepsis/bacteraemia included disease aetiology, particularly primary sclerosing cholangitis (adj-OR 15.09, 95% CI 12.24 to 18.60), alcohol (adj-OR 2.90, 95% CI 2.71 to 3.09), Charlson Comorbidity Index ≥3 (adj-OR 3.54, 95% CI 3.19 to 3.93) and diabetes (adj-OR 1.87, 95% CI 1.74 to 2.01). Overall case-fatality rate among admissions with sepsis/bacteraemia was 27.7% (95% CI 26.3% to 29.1%) vs 3.7% (95% CI 3.6% to 3.8%) without sepsis/bacteraemia. In-hospital death was significantly associated with sepsis/bacteraemia (adj-OR 6.50, 95% CI 5.95 to 7.11). The most common organisms identified were Escherichia coli and Staphylococcus aureus, present in 22.9% and 18.1%, respectively, of the 2265 admissions with a positive blood culture. The prevalence of MDR bacteria was low (5.6%)

Conclusion

Morbidity and mortality related to sepsis/bacteraemia in patients with cirrhosis remains a critical clinical problem.

Afebrile Bacteremia in Adult Emergency Department Patients with Liver Cirrhosis: Clinical Characteristics and Outcomes

Cirrhotic patients with bacteremia are at an increased risk of organ failure and mortality. In addition, they can develop serious infection without fever because of their impaired immune response. Our study aimed to investigate the clinical characteristics and outcomes in afebrile bacteremic patients with liver cirrhosis. A single-center, retrospective cohort study was performed on adult patients who visited the emergency department from January 2015 to December 2018. All patients with bacteremia and diagnosis of liver cirrhosis were enrolled and classified as either afebrile or febrile. In total, 104 bacteremic patients with liver cirrhosis (afebrile: 55 patients and, febrile: 49) were included in the study. Compared with the febrile group, patients in the afebrile group showed a significantly higher rate of inappropriate antibiotics administration (43.6% vs. 20.4%, p = 0.01). They were also at an increased risk of 30-day mortality (40% vs. 18.4%, p = 0.02), intensive care unit transfer (38.2% vs. 18.4%, p = 0.03) and endotracheal intubation (27.3% vs. 10.2%, p = 0.03). The afebrile state was also an independent risk factor associated with 30-day mortality in cirrhotic patients with bacteremia. Clinicians should perform a prudent evaluation in cirrhotic patients and carefully monitor for possible signs of serious infection even in the absence of fever.

Microbiological profile of pathogens in spontaneous bacterial peritonitis secondary to liver cirrhosis: a retrospective study

Spontaneous bacterial peritonitis (SBP) is an acute bacterial infection of ascitic fluid without an obvious source. The prevalence of SBP in patients with cirrhosis is in the range of 10%–30%. With increasing use of antibiotics, there is a gradual shift in the causative flora of SBP from Gram-negative bacteria to Gram-positive and, more importantly, to drug-resistant bacteria. The aim of this retrospective study on 721 cases was to identify the prevalence of various organisms causing SBP along with their drug sensitivity and resistance patterns. A prevalence of 38.2% culture positivity was observed in our South Indian population. Escherichia coli was the most common pathogen isolated. Third-generation cephalosporins showed high rates of resistance, but a susceptibility of 74.5% to amikacin was found. Nonetheless, 42% of culture-positive isolates exhibited multidrug resistance, the highest rates being seen with Enterococcus faecium (64.2%) and Acinetobacter baumannii (71.4%).

Multi-drug resistant bacteria predict mortality in bloodstream infection in a tertiary setting in Tanzania

Background

Bloodstream infections (BSI) are serious and life-threatening, associated with high mortality and morbidity. In resource-limited settings, there is a paucity of data on predictors of outcome in patients with BSI. This study aimed at examining the predictors of mortality in patients with BSI as well as bacteria causing BSI.

Methods and materials

This was a cross-sectional study conducted at Muhimbili National Hospital between April and May 2018. Blood culture results from all inpatients at the clinical microbiology laboratory were recorded and clinical information was retrieved retrospectively from the files. Bacteria from positive blood culture were identified and antimicrobial susceptibility was performed.

Results

The overall prevalence of BSI was, 46/402 (11.4% 95% CI 8.6–15), with a case fatality rate of 37%. There was a significantly high rate of BSI in patients who had died (19.5%) compared to those who survived (9.2%) p = 0.008. Gram-negative bacteria (74%) were the common cause of BSI, with a predominance of Enterobacteriaceae (22), followed by Pseudomonas aeruginosa (11). The majority of bacteria (70.5%) isolated from patients with BSI were Multi-drug resistant (MDR). Forty-six percent of Pseudomonas aeruginosa were resistant to meropenem while 68% (15/22) of Enterobacteriaceae were extended-spectrum β lactamase producers. Carbapenemase production was detected in 27% (3/11) of Pseudomonas aeruginosa and one Proteus mirabilis. Forty percent of Staphylococcus aureus were methicillin-resistant Staphylococcus aureus. Positive blood culture (aOR 2.24, 95%CI 1.12–4.47, p 0.02) and admission to the intensive care unit (aOR 3.88, 95%CI 1.60–9.41, p = 0.003) were independent factors for mortality in suspected BSI. Isolation of MDR bacteria was an independent predictor for mortality in confirmed BSI (aOR 15.62, 95%CI 1.24–161.38, p = 0.02).

Conclusion

The prevalence of BSI was 11.4%, with the majority of bacteria in BSI were MDR. Positive blood culture, admission to the ICU and MDR were predictors for mortality.

Treatment outcomes in patients with pyogenic vertebral osteomyelitis who have cirrhosis

Early diagnosis and proper treatment of pyogenic vertebral osteomyelitis (PVO) in patients with cirrhosis is challenging to clinicians, and the mortality rate is expected to be high. A retrospective study was conducted to investigate the treatment outcome in PVO patients with cirrhosis and to identify the predictors of their mortality. Mortality was divided into two categories, 30-day and 90-day mortality. A stepwise multivariate logistic regression model was used to identify predictors of mortality. Eighty-five patients were identified after initial exclusion. The patients’ mean age was 60.5 years, and 50 patients were male. The early mortality rates within 30 and 90 days were 17.6% and 36.5%, respectively. Multivariate analysis revealed that increased age, CTP class C, and bacteremia at the time of PVO diagnosis were predictors of 30-day mortality, while higher MELD score, presence of combined infection, and multiple spinal lesions were predictors of 90-day mortality. Attention should be paid to the high mortality between 30 and 90 days after PVO diagnosis (18.8%), which was higher than the 30-day mortality. Liver function was consistently a strong predictor of mortality in PVO patients with cirrhosis. The high-risk patients should be targeted for an aggressive diagnostic approach, using spinal MRI and intensive monitoring and treatment strategies.