Biliary tract infection and bacteraemia: presentation, structural abnormalities, causative organisms and clinical outcomes

Draft genomes of the bile duct microbiome strains Klebsiella pneumoniae and Enterococcus lactis isolated from bilioenteric drainages with biofilm-forming abilities

We describe the genetic properties of two strains isolated from the elusive bile duct microbiome from solid organ transplant patients. Bacterial strains Enterococcus lactis (MS-STENT-08-E-001) and Klebsiella pneumoniae (MS-STENT-01-M-001) were isolated from the biofilms of bile duct catheters.

Epidemiological, clinical and microbiological characteristics of patients with biliary tract diseases with positive bile culture in a tertiary hospital

PURPOSE

The prevalence of biliary tract diseases, which are common gastrointestinal disorders, is steadily rising. If it progresses to sepsis or septic shock, it can endanger the patient's life. Therefore, it is crucial to promptly diagnose bacterial infection in individuals suffering from biliary diseases and comprehend the risk factors associated with infection. The objective of this study was to examine the types of bacteria present in the bile of patients with biliary tract diseases, assess any alterations in their susceptibility to antimicrobial agents, and identify the risk factors contributing to the development of infection in these patients.

PATIENTS AND METHODS

From June 2019 to November 2022, 317 patients of biliary tract diseases with positive bile culture were included in this hospital-based descriptive analysis. The hospital's computerized medical records were used to collect data on demographic information (including gender, age, and occupation), laboratory, and clinical findings, physical examination results, comorbidities, basic diseases, treatment history, complications, and in-hospital outcomes. The study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) principles.

RESULTS

Of the 317 patients with positive biliary tract diseases, 247 had benign diseases and 70 had malignant diseases. Patients with benign disease experienced a higher prevalence of statistically significant symptoms such as abdominal pain (81.4% vs. 57.1%, P = 0.000), nausea (31.2% vs. 14.3%, P = 0.005), vomiting (30.0% vs. 12.9%, P = 0.004), and chills (10.9% vs. 2.9%, P = 0.039), while jaundice (12.6% vs. 37.1%, P = 0.000) was more common in patients with malignant disease. At the species level, Escherichia coli (105; 40.5%), Klebsiella pneumoniae (41; 15.8%), and Pseudomonas aeruginosa (30; 11.6%) were the most commonly found Gram-negative bacterial strains in biliary tract infection. Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa were most susceptible to tigecycline, ertapenem and ceftazidime/avibactam, respectively.

CONCLUSION

Gram-negative bacteria are the most commonly isolated biliary bacteria. Clinical doctors should pay attention to patients with malignant diseases with low hemoglobin, high total bilirubin and high alkaline phosphatase. Carbapenems, tigecycline, and minocycline are the recommended antibiotics for Enterobacteriaceae. In recent years, the proportion of enterococcus has gradually increased, and clinical attention should be paid to enterococcus infection. Linezolid and vancomycin were recommended for the treatment of Enterococci infections. Overall, this work can provide reference for clinical diagnosis, treatment and effective interventions.

Epidemiology of biliary tract-associated bloodstream infections and adequacy of empiric therapy: an Australian population-based study

PURPOSE

Although the biliary tract is a common source of invasive infections, the epidemiology of cholangitis- and cholecystitis-associated bloodstream infection (BSI) is not well defined. The objective of this study was to determine the incidence, clinical determinants, microbiology of biliary tract-associated BSI, and predicted adequacy of common empiric therapy regimens.

METHODS

All biliary tract-associated BSI in Queensland during 2000-2019 were identified using state-wide data sources. Predicted adequacy of empiric antimicrobial therapy was determined according to microbiological susceptibility data.

RESULTS

There were 3,698 episodes of biliary tract-associated BSI occurred in 3,433 patients of which 2,147 (58.1%) episodes were due to cholangitis and 1,551 (41.9%) cholecystitis, for age- and sex-standardized incidence rates of 2.7, and 2.0 per 100,000 population, respectively. An increasing incidence of biliary tract-associated BSI was observed over the study that was attributable to an increase in cholangitis cases. There was a significant increased risk for biliary tract-associated BSI observed with advancing age and male sex. Patients with cholangitis were older, more likely to have healthcare associated infection, and have more comorbidities most notably liver disease and malignancies as compared to patients with cholecystitis. The distribution of infecting pathogens was significantly different with polymicrobial aetiologies more commonly observed with cholangitis (18.4% vs. 10.5%; p < 0.001). The combination of ampicillin/gentamicin/metronidazole was predicted to have the overall highest adequacy (96.1%), whereas amoxicillin/clavulanate had the lowest (77.0%). Amoxicillin/clavulanate (75.2% vs. 79.4%, p:0.03) and ceftriaxone/metronidazole (83.4% vs. 89.6%; p < 0.001) showed significantly inferior predicted adequacy for cholangitis as compared to cholecystitis.

CONCLUSIONS

Bloodstream infections related to cholecystitis and cholangitis exhibit different epidemiology, microbiology, and requirements for empiric therapy.

Acute cholangitis: a state-of-the-art review

Acute cholangitis is a potentially life-threatening bacterial infection of the intra and/or extrahepatic bile ducts. It remains the second and third cause of community-acquired and hospital-acquired bacteremia, respectively, and is associated with mortality rates of up to 15%, despite advances in broad-spectrum antimicrobial therapy and improved access to emergency biliary tract decompression procedures. Even though not much has changed in recent years in terms of diagnosis or treatment, new data have emerged regarding multidrug-resistant bacteria that serve as etiologic agents of cholangitis. Moreover, different approaches in antibiotic regimes depending on severity grading and bile sample cultures as well as novel minimally invasive endoscopic procedures that can help when consecrated treatments such as endoscopic retrograde cholangiopancreatography (ERCP) fail, cannot be performed, or are unavailable have been proposed. This state-of-the-art review aims to offer a complete and updated assessment of the epidemiology, novel diagnostic and therapeutic methods, complications, and prognostic variables of acute cholangitis. The authors will review the prognostic implications of unusual complications, the relevance of regular bile samples and antibiograms, and their new role in guiding antibiotic therapy and limiting antibiotic resistance to present an organized and comprehensive approach to the care of acute cholangitis.

Comparison of antimicrobial therapy termination in febrile and afebrile patients with acute cholangitis after drainage

The standard treatment duration for acute cholangitis (AC) involves a 4-7-day antimicrobial treatment post-biliary drainage; however, recent studies have suggested that a ≤ 2-3 days is sufficient. However, clinical practice frequently depends on body temperature as a criterion for discontinuing antimicrobial treatment. Therefore, in this study, we assessed whether patients with AC can achieve successful outcomes with a ≤ 7-day antimicrobial treatment, even with a fever, assuming the infection source is effectively controlled. We conducted a single-center retrospective study involving patients with AC, defined following the Tokyo Guidelines 2018 for any cause, who underwent successful biliary drainage and completed a ≤ 7-day antimicrobial treatment. Patients were categorized into the febrile and afebrile groups based on their body temperature within 24 h before completing antimicrobial treatment. The primary outcome was the clinical cure rate, defined as no initial presenting symptoms by day 14 post-biliary drainage without recurrence or death by day 30. The secondary outcome was a 3-month recurrence rate. Logistic regression with inverse probability of treatment weighting was used. Overall, 408 patients were selected, among whom 40 (9.8%) were febrile. The two groups showed no significant differences in the clinical cure and 3-month recurrence rates. Notably, the subgroups limited to patients with a ≤ 3-day antibiotic treatment duration also showed no differences in these outcomes. Therefore, our results suggest that discontinuing antibiotics within the initially planned treatment period was sufficient for successful drainage cases of AC, regardless of the patient's fever status during the 24 h leading up to termination.

Guidelines for Antibiotics Prescription in Critically Ill Patients

How to cite this article: Khilnani GC, Tiwari P, Mittal S, Kulkarni AP, Chaudhry D, Zirpe KG, et al. Guidelines for Antibiotics Prescription in Critically Ill Patients. Indian J Crit Care Med 2024;28(S2):S104-S216.

The effects of photoactivated ciprofloxacin and bile acids on biofilms on bile duct catheters

OBJECTIVES

This study examined the potential of a novel photoactivatable ciprofloxacin to act against bacterial infections and microbiomes related to biliary diseases. It also evaluated treatment by combining the impact of bile acids and antibiotics on biofilms. Innovative strategies were evaluated to address the elusive bile duct microbiome resulting in biofilm-related infections linked to biliary catheters. The healthy biliary system is considered sterile, but bile microbiomes can occur in disease, and these correlate with hepatobiliary diseases. Causes include biofilms that form on internal-external biliary drainage catheters. These biliary catheters were used to noninvasively study the otherwise elusive bile microbiome for a pilot study.

METHODS

A new photoactivatable antibiotic was tested for efficacy against human-derived pathogenic bacterial isolates - Salmonella enterica and Escherichia coli - and catheter-derived bile duct microbiomes. In addition, the effect of bile acids on the antibiotic treatment of biofilms was quantified using crystal violet staining, confocal laser scanning microscopy, and biofilm image analysis. Two novel approaches for targeting biliary biofilms were tested.

RESULTS

A photoactivated antibiotic based on ciprofloxacin showed efficacy in preventing biofilm formation and reducing bacterial viability without harming eukaryotic cells. Furthermore, combination treatment of antibiotics with bile acids, such as ursodesoxycholic acid, mildly influenced biofilm biomass but reduced bacterial survival within biofilms.

CONCLUSION

Bile acids, in addition to their endocrine and paracrine functions, may enhance antibiotic killing of bacterial biofilms compared with antibiotics alone. These approaches hold promise for treating biliary infections such as cholangitis.

Primary Biliary Cholangitis With Pulmonary Manifestations and Concurrent Enterococcus Pneumonia: A Diagnostic Challenge Resembling Sarcoidosis or Silicosis

Primary biliary cholangitis (PBC) is common in females during middle age, presenting with fatigue and itching. In our case, an African-American male patient presented with abdominal pain, vomiting, fatigue, and lung manifestations such as interstitial lung disease, granulomatous lung disease, and pulmonary hypertension. In our case, the patient reported abdominal pain and fatigue with abnormal chest X-ray findings (bilateral pulmonic nodular lesion with calcifications), which mimicked silicosis/sarcoidosis lung findings such as bronchiectasis and parenchymal nodules. We diagnosed PBC as there was an absence of extrahepatic biliary obstruction and the presence of antimitochondrial antibodies (AMA) at a titer of 1:40 or higher. Bronchoalveolar lavage was performed due to the suspicion of interstitial lung disease and sarcoidosis, which was inconclusive but revealed enterococcus faecalis organisms. Initial antibiotic response heightens suspicion of infection, not colonization, leading to the diagnosis of enterococcal pneumonia. In our case, the diagnosis was made using clinical and laboratory criteria, and treatment with Ursodeoxycholic acid was opted for without resorting to more expensive and invasive tests like magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP). In summary, this case report presented the unique diagnostic challenges that will aid clinicians in considering a broad range of differential diagnoses and management plans.

Proteomic analysis of serum extracellular vesicles from biliary tract infection patients to identify novel biomarkers

Biliary tract infection (BTI), a commonly occurring abdominal disease, despite being extensively studied for its initiation and underlying mechanisms, continues to pose a challenge in the quest for identifying specific diagnostic biomarkers. Extracellular vesicles (EVs), which emanate from diverse cell types, serve as minute biological entities that mirror unique physiological or pathological conditions. Despite their potential, there has been a relatively restricted exploration of EV-oriented methodologies for diagnosing BTI. To uncover potent protein biomarkers for BTI patients, we applied a label-free quantitative proteomic method known for its unbiased and high-throughput nature. Furthermore, 192 differentially expressed proteins surfaced within EVs isolated from individuals afflicted with BTI. Subsequent GO and KEGG analyses pinpointed Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) and Crumbs homolog 3 (CRB3) as noteworthy biomarkers. Validation via data analysis of plasma-derived EV samples confirmed their specificity to BTI. Our study leveraged an unbiased proteomic tool to unveil CEACAM1 and CRB3 as promising protein biomarkers in serum EVs, presenting potential avenues for the advancement of diagnostic systems for BTI detection.

Antimicrobial therapy outcomes in acute cholangitis: Hilar multiple obstructions versus single hilar and common bile duct obstructions

Background and Aim

The appropriate duration of antimicrobial therapy for acute cholangitis (AC) arising from multiple hilar biliary obstructions as opposed to simple obstruction in the extrahepatic bile duct has not been established. This study assessed the efficacy of the duration of antimicrobial treatments in the Tokyo Guidelines 2018 for AC based on the cause and site of obstruction.

Methods

This single-center retrospective study involved patients with AC who underwent successful biliary drainage and completed a 7-day or shorter antimicrobial treatment. Patients were categorized into three groups: Group 1, bile duct stone or benign obstruction; Group 2, simple biliary obstruction due to malignancy; and Group 3, multiple hilar biliary obstruction due to malignancy. The primary outcome was clinical cure rate, and the secondary outcomes were 3-month recurrence rate and length of hospital stay.

Results

A total of 373 patients were selected. Patients in Group 3 were younger or had Charlson Comorbidity Index ≥4, and had fewer positive blood cultures. In Group 3, the clinical cure rate (87.1%) and 3-month recurrence rate (32.3%) were less favorable than those in the other groups. In Group 1, the clinical cure rate was significantly higher (98.1%, P = 0.02) with a much lower 3-month recurrence rate of only 3.4% (P < 0.001) than that in the other groups. The median hospital stay for all groups was 7 days.

Conclusion

This study suggests that the outcomes in Group 3 may be worse than those in Groups 1 or 2, regardless of the duration of the antibiotic treatment.

Variability of bile bacterial profiles and drug resistance in patients with choledocholithiasis combined with biliary tract infection: a retrospective study

Background

Biliary tract infection is a common complication of choledocholithiasis. This study aimed to analyse the distribution of pathogenic bacteria in bile cultures from patients with choledocholithiasis combined with biliary tract infection to guide clinical application of antimicrobials and reduce the emergence of drug resistance.

Methods

A total of 880 patients were enrolled in this retrospective study from 30 March 2017 to 31 August 2022 at the Affiliated Hospital of Qingdao University in China. Bile specimens were extracted for microbiological culture under aseptic conditions using endoscopic retrograde cholangiopancreatography. Bacterial culture, strain identification, and antimicrobial susceptibility testing were conducted according to the standard protocol. Baseline data were retrieved from patient files.

Results

Overall, 90.34% (795/880) of bile samples showed positive microbiological results and 37.50% (330/880) demonstrated polymicrobial infections. Among the 795 bile specimens with positive culture results, 1,216 pathogenic bacteria were detected, with gram-negative bacilli accounting for 56.33%, gram-positive cocci for 41.86%, and fungi for 1.81%. The predominant gram-negative bacilli in the bile cultures were Escherichia coli (30.43%) and Klebsiella pneumoniae (13.98%), whereas the main gram-positive cocci were Enterococcus faecium (14.04%) and E. casseliflavus (4.28%). The annual trend analysis revealed a gradual decrease in the proportion of gram-negative bacilli and a gradual increase in the proportion of gram-positive cocci, with a concomitant decrease in the dominance of E. coli. Both E. faecium and E. coli showed high resistance to conventional antibiotics but high sensitivity to piperacillin/tazobactam, carbapenems, amikacin, and vancomycin.

Conclusions

A significant change has occurred in the bile bacterial spectrum in patients with choledocholithiasis and biliary tract infection. The incidence of gram-positive cocci infections has increased annually, while that of gram-negative bacilli and E. coli infections has decreased. Antibiotic administration should be tailored based on the local bacterial profile.

Septic shock and biliary sepsis: 90-day mortality and associated risk factors

BACKGROUND

Biliary sepsis is common in patients with digestive cancer. Recommendations call for antibiotic de-escalation (ADE) as a strategy for antibiotic treatment of sepsis or septic shock. The aim of this study was to identify factors influencing 90-day mortality and to evaluate the impact of ADE.

METHODS

This retrospective study was conducted between November 2008 and December 2019 in a referral cancer center. Adults with biliary sepsis or septic shock admitted to the ICU were included. Variables associated with 90-day mortality were identified using univariate and multivariate Cox proportional hazards models.

RESULTS

122 patients were included. The 90-day mortality was 30.3% (n = 37). After multivariate analysis, the factors independently associated 90-day mortality were metastatic stage (p = 0.004), biliary tract tumour compression (p = 0.001), multi drug resistant (MDR) bacteria carriage on intensive care unit (ICU)admission (p = 0.048), serum lactate on ICU admission (p < 0.001), the use of extra-renal replacement (p = 0.008), factor V < 50% (p = 0.009) and performance status (ECOG-PS) > 2 (p < 0.001). ADE of the pivotal antibiotic (p = 0.041) and recent cancer surgery (p < 0.001) appeared to be associated with survival.

CONCLUSION

The 90-day mortality of biliary sepsis seems to be favourable. The 90-day mortality is associated with organ dysfunctions, but also with ECOG-PS, cancer stage, MDR bacteria colonisation. ADE seems to be safe.

A Rare Organism Causing Cholecystitis With Bacteremia in a Breast Cancer Patient

Pantoea, a gram-negative, rod-shaped, anaerobic bacterium, is a rare cause of human disease. Pantoea species have been known to mostly cause pulmonary disease in agricultural workers as they are native to select crops and wild animal furs. However, in very few documented cases, Pantoea has been discovered as the source of nosocomial infections, usually in the setting of an immunocompromised host. This case report details the clinical course of a 62-year-old immunocompromised female with stage 3 breast cancer presenting with acute cholecystitis and bacteremia and the unexpected discovery of Pantoea in peripheral and chemotherapy port blood cultures. After appropriate management and susceptibility testing, the patient fortunately recovered with initial cefepime and eventual levofloxacin to target the Pantoea species. To our knowledge, this is the third documented case worldwide of Pantoea isolated from cholecystitis with associated bacteremia and the first documented case in North America. Of special interest, a few months after her infection, the patient was found to be free of breast cancer. Pantoea species are known to contain levan, an exopolysaccharide, that has been seen to upregulate tumor suppressor genes. This should be considered in the future management and research of Pantoea infections.

Association of short-course antimicrobial therapy and bacterial resistance in acute cholangitis: Retrospective cohort study

Background and study aims Although the number of resistant bacteria tends to increase with prolonged antimicrobial therapy, no studies have examined the relationship between the duration of antimicrobial therapy and increase in the number of resistant bacteria in acute cholangitis. We hypothesized that the short-term administration of antimicrobial agents in acute cholangitis would suppress bacterial resistance. Patients and methods This was a single-center, retrospective, observational study of patients with acute cholangitis admitted between January 2018 and June 2020 who met the following criteria: successful biliary drainage, positive blood or bile cultures, bacteria identified from cultures sensitive to antimicrobials, and subsequent cholangitis recurrence by January 2022. The patients were divided into two groups: those whose causative organisms at the time of recurrence became resistant to the antimicrobial agents used at the time of initial admission (resistant group) and those who remained susceptible (susceptible group). Multivariate analysis was used to examine risk factors associated with the development of resistant pathogens. Multivariate analysis investigated antibiotics used with the length of 3 days or shorter after endoscopic retrograde cholangiopancreatography (ERCP) and previously reported risk factors for the development of bacterial resistance. Results In total, 89 eligible patients were included in this study. There were no significant differences in patient background or ERCP findings between the groups. The use of antibiotics, completed within 3 days after ERCP, was associated with a lower risk of developing bacterial resistance (odds ratio, 0.17; 95% confidence interval, 0.04-0.65; P =0.01). Conclusions In acute cholangitis, the administration of antimicrobials within 3 days of ERCP may suppress the development of resistant bacteria.

Clinico-epidemiological characteristics of the biliary samples and their antibiotic susceptibility pattern at a teaching hospital in Northern India

Introduction

Bile is deemed a sterile fluid, with the presence of clinical conditions like cholelithiasis, cholecystitis, previous biliary interventions, biliary strictures, and so on, leading to bile stasis, and increases the chances of bacteriobilia. In this study, we recognize the bacterial spectrum of microorganisms isolated from bile samples, diagnostic parameters, and antibiotic sensitivity patterns.

Methods

A retrospective observational study was carried out by compiling data from the hospital information system of a tertiary care center from 2021 to 2022 to evaluate biliary infections in patients who underwent surgical procedures related to the biliary tract and associated organs.

Results

A total of 234 patients' bile samples were included in our study. The mean age of patients was 48.04 ± 14.74 years, with more patients below the age of 65 years among those with infected bile samples. One hundred and sixty-three (163/234, 69.66%) patients infected by 209 pathogenic microorganisms were recognized. The most common microorganism isolated was Escherichia coli (83/209, 39.71%), followed by Pseudomonas aeruginosa (37/209, 17.7%). Acinetobacter baumannii and Klebsiella pneumoniae isolate owed to more than 90% penicillin, extended-spectrum beta-lactamase, carbapenem, and fluoroquinolone resistance among all isolates. Length of hospital stay, malignant obstruction, and chronic kidney disease were identified as statistically significant risk factors that lead to the isolation of multi-drug-resistant isolates from bile culture.

Conclusion

We recognized the spectrum of pathogens causing biliary tract infections at our center along with the antibiotic resistance pattern to guide and facilitate prompt and appropriate treatment by primary health care professionals and family medicine practitioners.

Diagnostic value of the serum lactate level as a predictor of bacteremia in patients with acute cholangitis

BACKGROUND

Patients with acute cholangitis (AC) have increased mortality when associated with bacteremia. This study aimed to evaluate the predictive ability of serum lactate (Lac) for positive bacteremia in patients with acute cholangitis.

METHODS

In this single-center, retrospective study, 138 consecutive patients with AC were analyzed. Their blood samples were collected and Lac was measured.

RESULTS

A total of 50 patients showed grade I, 50 showed grade II, and 38 showed grade III severity according to the Tokyo Guidelines 2018. Positive bacteremia was observed in 71 patients, of which 15 showed grade I, 25 showed grade II, and 31 showed grade III severity. Logistic regression analysis showed that Lac was a significant predictor of bacteremia. The area under the curve of Lac and procalcitonin (PCT) for bacteremia were 0.737 and 0.780, respectively. The optimal cutoff values for bacteremia were 17 mg/dL and 2.8 ng/mL, with sensitivity of 69.0% and 68.3%, respectively. Sensitivity of Lac and PCT for bacteremia in grade I was 58.3% and 25.0%, respectively. Three patients died from AC, all of whom were positive for bacteremia and hyperlactatemia.

CONCLUSION

Lac is useful for predicting bacteremia in patients with AC.

Early Management of Severe Biliary Infection in the Era of the Tokyo Guidelines

Sepsis of biliary origin is increasing worldwide and has become one of the leading causes of emergency department admissions. The presence of multi-resistant bacteria (MRB) is increasing, and mortality rates may reach 20%. This review focuses on the changes induced by the Tokyo guidelines and new concepts related to the early treatment of severe biliary disease. If cholecystitis or cholangitis is suspected, ultrasound is the imaging test of choice. Appropriate empirical antibiotic treatment should be initiated promptly, and selection should be performed while bearing in mind the severity and risk factors for MRB. In acute cholecystitis, laparoscopic cholecystectomy is the main therapeutic intervention. In patients not suitable for surgery, percutaneous cholecystostomy is a valid alternative for controlling the infection. Treatment of severe acute cholangitis is based on endoscopic or transhepatic bile duct drainage and antibiotic therapy. Endoscopic ultrasound and other new endoscopic techniques have been added to the arsenal as novel alternatives in high-risk patients. However, biliary infections remain serious conditions that can lead to sepsis and death. The introduction of internationally accepted guidelines, based on clinical presentation, laboratory tests, and imaging, provides a framework for their rapid diagnosis and treatment. Prompt assessment of patient severity, timely initiation of antimicrobials, and early control of the source of infection are essential to reduce morbidity and mortality rates.

Effectiveness of a new approach to minimally invasive surgery in palliative treatment of patients with distal malignant biliary obstruction

BACKGROUND

Palliative endoscopic biliary drainage is the primary treatment option for the management of patients with jaundice which results from distal malignant biliary obstruction (DMBO). In this group of patients, decompression of the bile duct (BD) allows for pain reduction, symptom relief, chemotherapy administration, improved quality of life, and increased survival rate. To reduce the unfavorable effects of BD decompression, minimally invasive surgical techniques require continuous improvement.

AIM

To develop a technique for internal-external biliary-jejunal drainage (IEBJD) and assess its effectiveness in comparison to other minimally invasive procedures in the palliative treatment of patients with DMBO.

METHODS

A retrospective analysis of prospectively collected data was performed, which included 134 patients with DMBO who underwent palliative BD decompression. Biliary-jejunal drainage was developed to divert bile from the BD directly into the initial loops of the small intestine to prevent duodeno-biliary reflux. IEBJD was carried out using percutaneous transhepatic access. Percutaneous transhepatic biliary drainage (PTBD), endoscopic retrograde biliary stenting (ERBS), and internal-external transpapillary biliary drainage (IETBD) were used for the treatment of study patients. Endpoints of the study were the clinical success of the procedure, the frequency and nature of complications, and the cumulative survival rate.

RESULTS

There were no significant differences in the frequency of minor complications between the study groups. Significant complications occurred in 5 (17.2%) patients in the IEBJD group, in 16 (64.0%) in the ERBS group, in 9 (47.4%) in the IETBD group, and in 12 (17.4%) in the PTBD group. Cholangitis was the most common severe complication. In the IEBJD group, the course of cholangitis was characterized by a delayed onset and shorter duration as compared to other study groups. The cumulative survival rate of patients who underwent IEBJD was 2.6 times higher in comparison to those of the PTBD and IETBD groups and 20% higher in comparison to that of the ERBS group.

CONCLUSION

IEBJD has advantages over other minimally invasive BD decompression techniques and can be recommended for the palliative treatment of patients with DMBO.

Comprehensive review on small common bile duct stones

Common bile duct stones are among the most common conditions encountered by endoscopists. Therefore, it is well researched; however, some items, such as indications for endoscopic papillary balloon dilatation (EPBD), safety of EPBD and endoscopic sphincterotomy in patients receiving dual antiplatelet therapy or direct oral anticoagulant, selection strategy for retrieval balloons and baskets, lack adequate evidence. Therefore, the guidelines have been updated with new research, while others remain unchanged due to weak evidence. In this review, we comprehensively summarize the standard methods in guidelines and new findings from recent studies on papillary dilation, stone retrieval devices, difficult-to-treat cases, troubleshooting during the procedure, and complicated cases of cholangitis, cholecystolithiasis, or distal biliary stricture.

Identification of Microbial Species and Analysis of Antimicrobial Resistance Patterns in Acute Cholangitis Patients with Malignant and Benign Biliary Obstructions: A Comparative Study

Background and Objectives: Acute cholangitis (AC) is still lethal if not treated promptly and effectively. Biliary drainage, also known as source control, has been acknowledged as the backbone treatment for patients with AC; nonetheless, antimicrobial therapy allows these patients to undergo non-emergent drainage procedures. This retrospective study aims to observe the bacterial species involved in AC and analyze the antimicrobial resistance patterns. Materials and Methods: Data were collected for four years, comparing patients with benign and malignant bile duct obstruction as an etiology for AC. A total of 262 patients were included in the study, with 124 cases of malignant obstruction and 138 cases of benign obstruction. Results: Positive bile culture was obtained in 192 (73.3%) patients with AC, with a higher rate among the benign group compared with malignant etiologies (55.7%.vs 44.3%). There was no significant difference between the Tokyo severity scores in the two study groups, identifying 34.7% cases of malignant obstruction with Tokyo Grade 1 (TG1) and 43.5% cases of TG1 among patients with benign obstruction. Similarly, there were no significant differences between the number of bacteria types identified in bile, most of them being monobacterial infections (19% in the TG1 group, 17% in the TG2 group, and 10% in the TG3 group). The most commonly identified microorganism in blood and bile cultures among both study groups was E. coli (46.7%), followed by Klebsiella spp. (36.0%) and Pseudomonas spp. (8.0%). Regarding antimicrobial resistance, it was observed that significantly more patients with malignant bile duct obstruction had a higher percentage of bacterial resistance for cefepime (33.3% vs. 11.7%, p-value = 0.0003), ceftazidime (36.5% vs. 14.5%, p-value = 0.0006), meropenem (15.4% vs. 3.6%, p-value = 0.0047), and imipenem (20.2% vs. 2.6%, p-value < 0.0001). Conclusions: The positive rate of biliary cultures is higher among patients with benign biliary obstruction, while the malignant etiology correlates with increased resistance to cefepime, ceftazidime, meropenem, and imipenem.

Addition of anaerobic coverage for treatment of biliary tract infections: a propensity score-matched cohort study

Objectives

To evaluate whether additional antibiotics that target anaerobes, including Bacteroides spp., are associated with improved clinical outcomes in patients with biliary tract infections (BTIs).

Methods

This was a retrospective propensity score-matched cohort of adults aged ≥18 years with BTIs, admitted to hospital between 1 April 2015 and 30 March 2021. Eligible patients treated with antibiotics that provided coverage of anaerobes were compared with those treated with comparable regimens without anaerobic coverage. The primary outcome was a composite of mortality within 30 days or relapse within 90 days of source control or completion of antibiotics. Secondary outcomes included length of stay (LOS), duration of antibiotic therapy and adverse drug reactions. ORs were calculated using a weighted generalized linear regression model with propensity-score matching.

Results

Among 398 patients included, 209 were treated without anaerobic coverage and 189 with anaerobic coverage. After propensity-score matching, there was no significant difference in primary outcome between propensity-matched patients who received additional anaerobic coverage and those who did not [adjusted OR (aOR) 1.23; 95% CI 0.69-2.22)]. Those with anti-anaerobic coverage had longer LOS (aOR 4.85; 95% CI 1.68-13.98) and longer duration of antibiotic treatment (aOR 4.14; 95% CI 2.61-6.57) than those who did not receive additional anaerobic therapy, but not more adverse drug reactions (aOR 1.01; 95% CI 0.97-1.05).

Conclusions

Omitting anti-anaerobic antibiotics may be a safe antimicrobial stewardship intervention. However, a randomized controlled trial may be warranted to definitively conclude whether additional anaerobic coverage in BTI treatment is necessary.

Understanding risk factors and microbial trends implicated in the development of Whipple-related surgical-site infections

Objective

The purpose of this study is to understand the role of risk factors and postoperative complications seen in patients undergoing Whipple procedures in the development of surgical site infections. Our secondary goal was to evaluate whether microbial patterns differed between preoperative antibiotic classes, offering insight into the effectiveness of current practices while promoting antibiotic stewardship.

Design

We performed a retrospective cohort study comparing patients with and without SSIs.

Setting

This study was conducted at a tertiary-care center in the southeastern United States.

Participants

Patients who underwent a Whipple procedure between 2012 and 2021 were acquired from the National Surgical Quality Improvement Program (NSQIP) database.

Results

Patients with a bleeding disorder reported higher SSI rates (P = .04), whereas patients with a biliary stent reported lower surgical site infection (SSI) rates (P = .02) Those with postoperative complications had higher SSI rates, including delayed gastric emptying (P < .001) and pancreatic fistula (P < .001). Patients with longer operative times were 1.002 times more likely to develop SSIs (adjusted odds ratio [aOR], 1.002; 95% confidence interval [CI], 1.001-1.004; P = .006) whereas surgical indications for malignancy correlated with decreased SSIs risk (aOR, 0.578; 95% CI, 0.386-866) when adjusting for body mass index, surgical indication, and duration of surgical procedure.

Conclusions

Optimizing preoperative management of modifiable risk factors for patients undergoing pancreatoduodenectomies and decreasing operative times may reduce SSI rates and patient and hospital burden. Further research is needed to understand whether stent placement reduces SSI risk in pancreatoduodenectomy.

Impact of Inappropriate Empirical Antibiotic on Outcomes in Community-acquired Third Generation Cephalosporin Resistant Enterobacterales Bacteremia

BACKGROUND

Currently, third generation cephalosporin resistant Enterobacterales (3GCRE) are becoming more common in community-acquired infection, leading to increasing consumption of carbapenems. Because community-acquired 3GCRE infections are generally less severe and of lower pathogenicity, the impact of inappropriate empirical antibiotics among patients with community-acquired 3GCRE bacteremia remains unknown.

MATERIALS AND METHODS

This prospective cohort study included adult patients with 3GCRE bacteremia from April 2018 to December 2021. Participants were followed for 30 days to measure the primary outcome of mortality. Propensity score analysis was performed to adjust for treatment selection bias.

RESULTS

A total of 155 patients met the eligible criteria (42 participants in the appropriate antibiotics group, and 113 participants in the inappropriate antibiotics group). Eight participants in the inappropriate antibiotics group never received appropriate antibiotics, three of whom died before microbiological results were made available. The most common clinical syndromes were urinary tract infection (56.8%) and biliary tract infection (22.6%). The overall 30-day mortality rate was 12.9%, 14.3% in the appropriate empirical antibiotics group and 12.4% in the inappropriate empirical antibiotics group. After propensity score weighted adjustment, the 30-day mortality rate in the inappropriate group was non-inferior to the appropriate group (mean difference 1.9%; 95% confidence interval: -10.1 - 14.0). From the multivariate analysis, acute respiratory failure and primary bacteremia were associated with 30-day mortality.

CONCLUSION

Among patients with community-acquired 3GCRE bacteremia, inappropriate empirical treatment given within 24 hours after the onset of bacteremia was non-inferior to appropriate antibiotics. In the setting of a high prevalence of 3GCRE carriage in community, adjustment to carbapenem might be tolerable among patients with community-acquired infections.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03765749.

Infectious complications of non-surgical biliary tract manipulation in paediatric patients. Role of antibiotic prophylaxis

BACKGROUND

Infections related to non-surgical manipulation of the biliary tract (NSMBT) are common events despite periprocedural antibiotic prophylaxis (PAP). Since June 2017, our local protocol has indicated a 24-h regimen of intravenous piperacillin-tazobactam for this purpose.

OBJECTIVE

We aimed to describe the incidence and characteristics of NSMBT-related paediatric infections, define risk factors for their development, and analyse adherence to our PAP protocol.

MATERIALS AND METHODS

Epidemiological, clinical, and microbiological data were collected in consecutive NSMBT procedures performed in paediatric patients (<18 years) in our centre (2010-2019).

RESULTS

113 procedures in 37 patients, median age 4 years (IQR 1-8), were included. Main underlying diseases were biliary atresia (32%) and cancer (14%). Sixty-eight percent had undergone liver transplant and 70% hepaticojejunostomy. In 44 procedures (39%), the intervention was performed during the course of infection and previously prescribed antibiotic treatment was maintained. In the other 69, PAP was specifically indicated for NSMBT; antibiotic adequacy increased from 35% to 100% after June 2017. In total, 32 NSMBT-related infections (28%) occurred, mainly in the first 24h post-procedure (72%); no deaths happened. Causative pathogens were Gram-negative rods (64%), Gram-positive cocci (28%), and Candida spp. (8%). Main related risk factors were hepaticojejunostomy, biliary obstruction, and liver transplant.

CONCLUSIONS

NSMBT in children entails a significant infection risk, even under antibiotic prophylaxis, being hepaticojejunostomy the main risk factor. Infectious complications mainly occurred immediately after the procedure. After establishing a PAP protocol, 100% of interventions received appropriate prophylaxis, decreasing antibiotic exposure time and potentially, the length of hospital stay.

Implications of Type 2 Diabetes Mellitus in Patients with Acute Cholangitis: A Systematic Review of Current Literature

Introduction: Type 2 diabetes mellitus (T2DM) has been associated with higher rates and poorer prognosis of infections, mainly due to poor glycemic control, reduced response of T-cells and neutrophils, and impaired migration, phagocytosis, and chemotaxis of leukocytes. However, the impact of T2DM on acute cholangitis (AC) has not been assessed so far. Thus, we aimed to explore this association by means of a systematic review of the literature. Methods: This systematic review was carried out based on the recommendations stated in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched the PubMed/MEDLINE, Web of Science and SCOPUS databases to identify relevant publications depicting an association between T2DM and AC from the inception of these search services up to present. Results: We detected a total of 435 eligible records. After we applied the inclusion and exclusion criteria, a total of 14 articles were included in the present systematic review. Included manuscripts focused on the potential role of T2DM as a risk factor for the development of AC and on its contribution to a worse prognosis in AC, e.g., development of sepsis or other complications, the risk of AC recurrence and the impact on mortality. Conclusions: As compared to non-diabetic individuals, patients with T2DM have a higher risk of AC as a complication of choledocholithiasis or gallstone pancreatitis. Several oral hypoglycemic drugs used in the management of T2DM may also be involved in the onset of AC. Diabetic patients who suffer from AC have a higher likelihood of longer hospital stays and sepsis, as well as a higher risk of mortality and more severe forms of AC as compared to non-diabetic individuals.

Bile Acids: Major Regulator of the Gut Microbiome

Bile acids are synthesized from cholesterol and play an important role in regulating intestinal microflora. The different degrees of hydrophobicity and acidity of individual bile acids may affect their antimicrobial properties. We examined the antimicrobial effects of different bile acids on various microorganisms in vitro and confirmed whether these remain consistent in vivo. Using human bile acids, including ursodeoxycholic acid, cholic acid, chenodeoxycholic acid, deoxycholic acid, and lithocholic acid, a disc diffusion test was performed, and a rodent model was created to determine the antimicrobial effects of each bile acid. The fecal bacterial population was analyzed using a real-time polymerase chain reaction. Each bile acid showed different microbial inhibitory properties. The inhibitory activity of bile acids against microbiota which normally resides in the gastrointestinal tract and biliary system, was low; however, normal flora of other organs was significantly inhibited. Changes in microbial counts after bile acid administration in a rodent model differed in the colon and cecum. The in vivo and in vitro results show that the antimicrobial effects of bile acids against intestinal microbiota were similar. In conclusion, bile acids could be a novel treatment strategy to regulate gut microbiota.

Risk Factors and Predictive Score for Bacteremic Biliary Tract Infections Due to Enterococcus faecalis and Enterococcus faecium: a Multicenter Cohort Study from the PROBAC Project

Biliary-tract bloodstream infections (BT-BSI) caused by Enterococcus faecalis and E. faecium are associated with inappropriate empirical treatment and worse outcomes compared to other etiologies. The objective of this study was to investigate the risk factors for enterococcal BT-BSI. Patients with BT-BSI from the PROBAC cohort, including consecutive patients with BSI in 26 Spanish hospitals between October 2016 and March 2017, were selected; episodes caused by E. faecalis or E. faecium and other causes were compared. Independent predictors for enterococci were identified by logistic regression, and a predictive score was developed. Eight hundred fifty episodes of BT-BSI were included; 73 (8.5%) were due to target Enterococcus spp. (48 [66%] were E. faecium and 25 [34%] E. faecalis). By multivariate analysis, the variables independently associated with Enterococcus spp. were (OR; 95% confidence interval): cholangiocarcinoma (4.48;1.32 to 15.25), hospital acquisition (3.58;2.11 to 6.07), use of carbapenems in the previous month (3.35;1.45 to 7.78), biliary prosthesis (2.19;1.24 to 3.90), and moderate or severe chronic kidney disease (1.55;1.07 to 2.26). The AUC of the model was 0.74 [95% CI0.67 to 0.80]. A score was developed, with 7, 6, 5, 4, and 2 points for these variables, respectively, with a negative predictive value of 95% for a score ≤ 6. A model, including cholangiocarcinoma, biliary prosthesis, hospital acquisition, previous carbapenems, and chronic kidney disease showed moderate prediction ability for enterococcal BT-BSI. Although the score will need to be validated, this information may be useful for deciding empirical therapy in biliary tract infections when bacteremia is suspected. IMPORTANCE Biliary tract infections are frequent, and a significant cause of morbidity and mortality. Bacteremia is common in these infections, particularly in the elderly and patients with cancer. Inappropriate empirical treatment has been associated with increased risk of mortality in bacteremic cholangitis, and the probability of receiving inactive empirical treatment is higher in episodes caused by enterococci. This is because many of the antimicrobial agents recommended in guidelines for biliary tract infections lack activity against these organisms. To the best of our knowledge, this is the first study analyzing the predictive factors for enterococcal BT-BSI and deriving a predictive score.

Antibiotic Administration within Two Days after Successful Endoscopic Retrograde Cholangiopancreatography Is Sufficient for Mild and Moderate Acute Cholangitis

To prevent the increase of resistant bacteria, it is important to minimize the use of antimicrobial agents. Studies have found that administration for ≤3 days after successful endoscopic retrograde cholangiopancreatography (ERCP) is appropriate. Therefore, the present study aimed to verify if administration of antimicrobial agents can be further shortened to ≤2 days after ERCP. We divided 390 patients with mild and moderate cholangitis who underwent technically successful ERCP from January 2018 to June 2020 and had positive blood or bile cultures into two groups: antibiotic therapy within two days of ERCP (short-course therapy, SCT; n = 59, 15.1%), and for >3 days (long-course therapy, LCT; n = 331, 84.9%). The increased severity after admission and other outcomes were compared between the two groups, and the risk factors for increased severity were verified. There were no between-group differences in patient characteristics. Total length of hospital stay was shorter in SCT than in LCT, and other outcomes in SCT were not significantly different from those in LCT. Being 80 or older was a risk factor for increased severity; however, SCT was not associated with increased severity. Antimicrobial therapy for ≤2 days after successful ERCP is adequate in patients with mild and moderate acute cholangitis.

Tardive peritonitis after the endoscopic ultrasound‐guided hepaticogastorostomy: A case report

Endoscopic ultrasound‐guided biliary drainage (EUS‐BD) has become popular as a new drainage technique for malignant biliary strictures. Although EUS‐BD has been reported to show high technical and clinical success rates, the rate of adverse events is 15%. In particular, peritonitis, which is generally caused by bile leakage from the aspiration side during the procedure and occurs within a few days after EUS‐BD, needs to be considered as it can be fatal. In the present case, a jaundiced patient presented with unresectable pancreatic adenocarcinoma. Due to duodenal invasion, we performed EUS‐guided hepaticogastrostomy for biliary drainage. After the procedure, jaundice improved, and abdominal computed tomography (CT) showed only a small amount of air in the intrahepatic bile duct. However, 7 days after the procedure, the patient developed fever, and clinical findings indicated peritonitis. Abdominal CT showed food in the stomach accompanied by the appearance of perihepatic free air, with increased air in the intrahepatic bile duct. The duodenal stent insertion settled the peritonitis and improved the perihepatic free air and the air in the intrahepatic bile duct through the discharge of food from the stomach. To date, no case of tardive peritonitis associated with air leakage after EUS‐BD has been reported. We noted that even if there was no evidence of bile leakage after EUS‐BD, the possibility of tardive peritonitis due to gradual air leakage from the stent implantation side of the stomach should be considered, and careful follow‐up is needed.

Proton Pump Inhibitor Use Increases Pyogenic Liver Abscess Risk: A Nationwide Cohort Study

Background/Aims

Proton pump inhibitors (PPIs) increase gastric pH and alter the gut microbiome. An increased risk for infectious diseases has been reported in PPI users. However, little is known about the association of PPI use with pyogenic liver abscess (PLA) incidence risk.

Methods

We conducted a population-based cohort study using data from a nationwide representative sample of the Korean general population followed up for 10 years (January 1, 2003 to December 31, 2013). We identified PPI prescriptions and considered PPI as a timevarying variable. Proportional hazards regression model was used for incident PLA comparing PPI use versus non-use. Propensity score matching was also conducted.

Results

During the 4 209 229 person-years of follow-up, 58 595 participants had at least 1 PPI prescription and 541 patients developed liver abscess. The age-, sex-, residential area-, and income-adjusted hazard ratio for PLA incidence with PPI use was 4.19 (95% CI, 2.54- 6.92). The association was observed in fully adjusted models (hazard ratio 3.88; 95% CI, 2.33-6.44). The positive association between PPI use and PLA was consistent in all subgroups analyzed and in propensity score matching group.

Conclusion

The present data indicate that PPI use is associated with an increased PLA risk. Therefore, it is necessary to prescribe PPIs with clear indication and to avoid improper use of PPIs.

Effect of Antibiotic Resistance of Pathogens on Initial Antibiotic Therapy for Patients With Cholangitis

Objectives

Considering that pathogens resistant to initial antibiotic therapies for cholangitis can affect mortality rates, appropriate initial empiric antibiotic therapy is important. However, evidence regarding the influence of pathogens resistant to initial antibiotics in patients with cholangitis who have undergone early endoscopic retrograde cholangiopancreatography (ERCP) is limited, and the conditions in several cases can improve with early ERCP even when pathogens resistant to initial antibiotics are detected on time. Therefore, this study aimed to assess the influence of pathogens resistant to initial antibiotics on the course of cholangitis in patients undergoing early ERCP.

Materials and methods

Patients (n=266) with positive blood or bile culture results treated with early ERCP were divided into those with cultures that were resistant to the initial antibiotics (antibiotic-resistant group; n=66; 24.8%) and those with cultures that were sensitive to the initial antibiotics (antibiotic-sensitive group; n=200; 75.2%). The duration of hospitalization, in-hospital mortality rates due to cholangitis, rates of increased disease severity, and complications during hospitalization were studied.

Results

Enterococcus, Enterobacter, Citrobacter, and Pseudomonas species showed high resistance to several antibiotics. No significant between-group differences were found in the duration of hospitalization, in-hospital mortality rates due to cholangitis, and rates of increased disease severity. However, the rate of post-ERCP cholecystitis was significantly higher in the antibiotic-resistant group than in the antibiotic-sensitive group (p=0.0245).

Conclusions

Even if the initial antibiotics were ineffective, the rate of fatal outcomes did not increase among patients with cholangitis who had undergone early ERCP. However, when initial antibiotics were ineffective, the frequency of post-ERCP cholecystitis increased even after early bile duct decompression.

Intestinal fatty acid-binding protein is a biomarker for diagnosis of biliary tract infection

Background and Aim

Biliary tract infection (BTI) is an inflammatory disease and commonly associated with bacteremia. Delays in diagnosis or treatment of BTI cause high morbidity and mortality. However, an early diagnosis depends on appropriate clinical investigations. Appropriate biomarkers are urgently needed to improve the BTI diagnostic rate. We hypothesized that intestinal fatty acid‐binding protein (I‐FABP) might be a potential biomarker for BTI diagnosis.

Methods

We examined data from subjects aged ≥18 years diagnosed with BTI, including cholangitis and cholecystitis, whose blood samples were adequate for I‐FABP and zonulin assessment. We also collected blood samples from healthy volunteers as the control group. We excluded subjects in both groups who received steroids, antibiotics, or probiotics within 1 month before hospital admission (BTI cohort) or participation in this research (controls). The main study endpoint was to compare the diagnostic ability of I‐FABP to detect BTI in comparison with high‐sensitivity C‐reactive protein (hs‐CRP) and zonulin.

Results

The study collected the data of 51 patients with BTI and 35 healthy subjects. The receiver operating characteristic (ROC) area under the curve (AUC) for I‐FABP was 0.884 (95% confidence interval [CI]: 0.814–0.954), numerically higher than that for hs‐CRP (0.880; 0.785–0.976) and zonulin (0.570; 0.444–0.697). We estimated that the optimal cutoff value of I‐FABP was 2.1 ng/mL (sensitivity: 0.804; specificity: 0.829) for the diagnosis of BTI.

Conclusions

In summary, this study suggests that I‐FABP may be a potential alternative biomarker to hs‐CRP for diagnosing BTI. Further research should verify the use of I‐FABP as a marker for BTI diagnosis, but also for other inflammatory diseases.

Blood cultures should be collected for acute cholangitis regardless of severity

BACKGROUND

Despite the high frequency of bacteremia in acute cholangitis, the indications for blood cultures and the relationship between the incidence of bacteremia and severity of acute cholangitis have not been well established. This study examined the association between the 2018 Tokyo Guidelines (TG18) severity grading for acute cholangitis and incidence of bacteremia to identify the need for blood cultures among patients with acute cholangitis in each severity grade.

METHODS

Patients with acute cholangitis who visited our emergency department between 2019 and 2020 were retrospectively investigated. Patients administered antibiotics within 48 h of hospital arrival, whose prothrombin time-international normalized ratios were not measured, or who were suspected of false bacteremia were excluded.

RESULTS

Out of the included 358 patients with acute cholangitis, blood cultures were collected from 310 (87%) patients, of which 148 (48%) were complicated with bacteremia. As the TG18 severity grading increased, the frequency of bacteremia increased (Grade I, 35% [59/171]; Grade II, 59% [48/82]; Grade III, 74% [42/57]; P <0.001). Agreement with the TG18 diagnostic criteria (unfulfilled, suspected, or definite) was not different between patients with and without bacteremia; however, 36% (14/39) of the patients with "unfulfilled" criteria were complicated with bacteremia.

CONCLUSIONS

As the severity of acute cholangitis increased, the frequency of bacteremia increased; however, the incidence of bacteremia was high even in mild cases and cases that did not meet the TG18 diagnostic criteria. Blood cultures should be collected regardless of the severity of acute cholangitis for patients who visit the emergency department.

Enterococcal Infections the First Year after Liver Transplantation-A Prospective Cohort Study

This study aimed to investigate the incidence of enterococcal infections and determine risk factors associated with enterococcal bloodstream infection (BSI) within the first year post-liver transplantation (LTx). We included 321 adult liver transplant recipients transplanted from 2011 to 2019 in a prospective cohort study. Cumulative incidence of enterococcal infections and risk factors associated with BSI were investigated in a competing risk model and time-updated Cox models, respectively. A total of 223 enterococcal infections were identified in 89 recipients. The cumulative incidences of first enterococcal infection and first enterococcal BSI were 28% (95% CI (23-33)) and 11% (CI (7-14)), respectively. Risk factors associated with enterococcal BSI were previous infections in the biliary tract (HR, 33; CI (15-74); p < 0.001), peritoneum (HR, 8.1; CI (3-23); p < 0.001) or surgical site (HR, 5.5; CI (1.4-22); p = 0.02), recipient age (HR per 10 years increase, 1.2; CI (1.03-1.6); p = 0.03), and cold ischemia time (HR per one hour increase, 1.2; CI (1.1-1.3); p < 0.01). Enterococcal infections are highly prevalent the first year post-LTx, and recipients with enterococcal infections in the biliary tract, peritoneum, or surgical site are at increased risk of BSI. These findings may have implications for the choice of empiric antibiotics early post-LTx.

The Importance of Early Management of Severe Biliary Infection: Current Concepts

Background

The incidence of biliary infections is rising worldwide and has become one of the main reasons for emergency admissions.

Methods

This is a narrative review of the literature emphasizing news concepts related to the early management of biliary diseases.

Results

The bacteriology is frequently polymicrobial, with a progressive increase of multidrug resistant bacteria. The form of presentation is variable, and the mortality rate may reach 20%. When cholecystitis or cholangitis is suspected, ultrasound is the gold standard imaging test. Depending on the severity of presentation, local resistances, and risk factors for multiresistant organisms, the most appropriate empirical antibiotic treatment must be initiated. In acute cholecystitis, cholecystectomy plays the main therapeutic role. In patients not suitable for surgery, percutaneous cholecystostomy is a valid alternative for source control. Treatment of severe cholangitis is based on the drainage of the bile duct and antibiotic therapy.

Conclusions

Biliary infections are serious conditions that can lead to sepsis and death. The introduction of new internationally accepted guidelines, based on clinical presentation, laboratory tests, and imaging, provides a platform for their timely diagnosis and management. Early severity assessment, initiation of intravenous antibiotics, and source control are fundamental to improving morbidity and mortality.

Association of Microbial Dysbiosis with Gallbladder Diseases Identified by Bile Microbiome Profiling

BACKGROUND

Cholecystitis is an important risk factor for gallbladder cancer, but the bile microbiome and its association with gallbladder disease has not been investigated fully. We aimed to analyze the bile microbiome in normal conditions, chronic cholecystitis, and gallbladder cancer, and to identify candidate bacteria that play an important role in gallbladder carcinogenesis.

METHODS

We performed metagenome sequencing on bile samples of 10 healthy individuals, 10 patients with chronic cholecystitis, and 5 patients with gallbladder cancer, and compared the clinical, radiological, and pathological characteristics of the participants.

RESULTS

No significant bacterial signal was identified in the normal bile. The predominant dysbiotic bacteria in both chronic cholecystitis and gallbladder cancer were those belonging to the Enterobacteriaceae family. Klebsiella increased significantly in the order of normal, chronic cholecystitis, and gallbladder cancer. Patients with chronic cholecystitis and dysbiotic microbiome patterns had larger gallstones and showed marked epithelial atypia, which are considered as precancerous conditions.

CONCLUSION

We investigated the bile microbiome in normal, chronic cholecystitis, and gallbladder cancer. We suggest possible roles of Enterobacteriaceae, including Klebsiella, in gallbladder carcinogenesis. Our findings reveal a possible link between a dysbiotic bile microbiome and the development of chronic calculous cholecystitis and gallbladder cancer.

BACTERIAL ISOLATES AND ANTIBIOTIC SENSITIVITY PATTERNS IN CHOLEDOCHAL BILE COLLECTED DURING ERCP: A REPORT FROM CENTRAL INDIA

Temporal shifts have been known to occur in antibiotic sensitivity patterns of organisms causing cholangitis.The aim of this prospective study conducted on 100 patients of extra hepatic biliary obstruction (EHBO) was to identify the common microorganisms cultured from bile obtained during Endoscopic retrograde cholangiography and to study their local sensitivity pattern.Sixty six patients had growth in bile culture,the maximum growths amongst all micro-organisms were of Escherichia coli (40.9%) and Pseudomonas aeruginosa (40.9%). Growth rates were significantly higher in patients with non- malignant causes of biliary obstruction than those with malignant causes. Polymixins had the highest sensitivity to cultured bacteria followed by aminoglycosides and Imipenem.Study of culture & sensitivity pattern helps in deciding empirical antibiotic therapy in patients with cholangitis and it should be based on local sensitivity patterns

Epidemiology of Escherichia coli Bacteremia: A Systematic Literature Review

BACKGROUND

Escherichia coli is the most common cause of bacteremia in high-income countries. To enable the development and implementation of effective prevention strategies, a better understanding of the current epidemiology of invasive E. coli infections is needed.

METHODS

A systematic review of literature published between 1 January 2007 and 31 March 2018 on the burden and epidemiology of E. coli bacteremia in populations that include adults in high-income countries was conducted. Meta-analysis was performed for descriptive purposes.

RESULTS

During the studied time interval, the estimated incidence rate of E. coli bacteremia was 48 per 100 000 person-years, but this increased considerably with age: rates per 100 000 person-years were >100 in 55-to-75-year-olds and >300 in 75-to-85-year-olds. Overall, E. coli accounted for 27% of documented bacteremia episodes: 18% if hospital acquired, 32% if community-onset healthcare associated, and 33% if community acquired. The estimated case fatality rate was 12%. Approximately 44% of episodes were community acquired, 27% community-onset healthcare associated, and 27% hospital acquired. Urinary tract infection (UTI) was the primary source for 53% of episodes.

CONCLUSIONS

This systematic review confirms the substantial burden of E. coli bacteremia in older adults and justifies the implementation of community-level programs to prevent E. coli bacteremia and ideally UTI in this age group.

Infectious complications of non-surgical biliary tract manipulation in paediatric patients. Role of antibiotic prophylaxis

BACKGROUND

Infections related to non-surgical manipulation of the biliary tract (NSMBT) are common events despite periprocedural antibiotic prophylaxis (PAP). Since June 2017, our local protocol has indicated a 24-h regimen of intravenous piperacillin-tazobactam for this purpose.

OBJECTIVE

We aimed to describe the incidence and characteristics of NSMBT-related paediatric infections, define risk factors for their development, and analyse adherence to our PAP protocol.

MATERIALS AND METHODS

Epidemiological, clinical, and microbiological data were collected in consecutive NSMBT procedures performed in paediatric patients (<18 years) in our centre (2010-2019).

RESULTS

113 procedures in 37 patients, median age 4 years (IQR 1-8), were included. Main underlying diseases were biliary atresia (32%) and cancer (14%). Sixty-eight percent had undergone liver transplant and 70% hepaticojejunostomy. In 44 procedures (39%), the intervention was performed during the course of infection and previously prescribed antibiotic treatment was maintained. In the other 69, PAP was specifically indicated for NSMBT; antibiotic adequacy increased from 35% to 100% after June 2017. In total, 32 NSMBT-related infections (28%) occurred, mainly in the first 24h post-procedure (72%); no deaths happened. Causative pathogens were Gram-negative rods (64%), Gram-positive cocci (28%), and Candida spp. (8%). Main related risk factors were hepaticojejunostomy, biliary obstruction, and liver transplant.

CONCLUSIONS

NSMBT in children entails a significant infection risk, even under antibiotic prophylaxis, being hepaticojejunostomy the main risk factor. Infectious complications mainly occurred immediately after the procedure. After establishing a PAP protocol, 100% of interventions received appropriate prophylaxis, decreasing antibiotic exposure time and potentially, the length of hospital stay.

Microbiology and risk factors for gram-positive Cocci bacteremia in biliary infections

BACKGROUND

The rapid antibiotics treatment targeted to a specific pathogen can improve clinical outcomes of septicemia. We aimed to evaluate the clinical characteristics and outcomes of biliary septicemia caused by cholangitis or cholecystitis according to causative organisms.

METHODS

We performed a retrospective cohort study in 151 patients diagnosed with cholangitis or cholecystitis with bacterial septicemia from January 2013 to December 2015. All patients showed clinical evidence of biliary tract infection and had blood isolates that demonstrated septicemia.

RESULTS

Gram-negative, gram-positive, and both types of bacteria caused 84.1% (127/151), 13.2% (20/151), and 2.6% (4/151) episodes of septicemia, respectively. The most common infecting organisms were Escherichia coli among gram-negative bacteria and Enterococcus species (Enterococcus casseliflavus and Enterococcus faecalis) among gram-positive bacteria. There were no differences in mortality, re-admission rate, and need for emergency decompression procedures between the gram-positive and gram-negative septicemia groups. In univariate analysis, previous gastrectomy history was associated with gram-positive bacteremia. Multivariate analysis also showed that previous gastrectomy history was strongly associated with gram-positive septicemia (Odds ratio = 5.47, 95% CI: 1.19-25.23; P = 0.029).

CONCLUSIONS

Previous gastrectomy history was related to biliary septicemia induced by gram-positive organisms. This information would aid the choice of empirical antibiotics.

Clinical Significance of Changes in Gut Microbiome Associated with Use of Proton Pump Inhibitors

Proton pump inhibitors (PPIs) are commonly used for the treatment of gastric acid-related disorders, and are generally well tolerated. However, by reducing the secretion of gastric acid in the long term, PPI can increase the risk of inducing an imbalance in the gut microbiome composition. Moreover, gastric hypochlorhydria that is caused by PPIs favors the survival and migration of oral bacteria in the lower part of the gastrointestinal tract, with a possible induction of pro-inflammatory microenvironment. Therefore, gut dysbiosis that is associated with the use of PPI has been found to cause adverse infectious and inflammatory diseases. In this regard, adverse effects of the PPI-related gut dysbiosis have been reported in different observational studies, but their clinical relevance remains unclear. Therefore, the aim of this review was to explore the available data on the PPI-related gut dysbiosis in order to better understand its clinical significance.

Clinical evaluation of cefotiam in the treatment of bacteremia caused by Escherichia coli, Klebsiella species, and Proteus mirabilis: A retrospective study

Bacteremia is often caused by gram-negative bacteria (represented by EKP; Escherichia coli, Klebsiella species, and Proteus mirabilis), and the excessive use of cefazolin, as the first-line antimicrobial in its treatment, has been a source of concern in the emergence of resistant strains. As an antimicrobial, cefotiam may be an alternative to cefazolin; however, little evidence is available for its use in the treatment of bacteremia. The purpose of this non-inferiority study was to retrospectively compare the therapeutic efficacy of cefotiam with some antimicrobials of narrow spectrum (cefazolin, cefmetazole, and flomoxef) in the treatment of EKP-induced bacteremia. The number of patients recruited was 32 in the cefotiam group and 29 in the control group. In the primary endpoint, the survival rate on day 28 for the cefotiam group and the control group was 93.5% and 89.3%, respectively (relative risk at day 28, 1.048; 95% confidence interval, 0.894-1.227). In the secondary end point, treatment success rate in the two groups was 71.9% and 69.0%, respectively (relative risk, 1.042; 95% confidence interval, 0.752-1.445). Intensive care unit admission, low body weight, hypoalbuminemia, and infections unassociated with the urinary tract were identified to be the risk factors responsible for treatment failure. We demonstrated cefotiam may be non-inferior to other antimicrobials of similar spectrum, in terms of survival rate, in EKP-induced bacteremia.

Antibiotics in the Biliary Tract: A Review of the Pharmacokinetics and Clinical Outcomes of Antibiotics Penetrating the Bile and Gallbladder Wall

Biliary tract infections (BTIs), including cholangitis and cholecystitis, are common causes of bacteremia. Bacteremic BTIs are associated with a mortality rate of 9-12%. The extent to which antibiotics are excreted in the bile and the ratio of their exposure to the minimum inhibitory concentration of the infecting organism are among the important factors for the treatment of BTIs. This review updates health care professionals on the distribution of antibiotics in the common bile duct, gallbladder, and gallbladder wall. Antibiotic efficacy in treating BTIs based on the latest available clinical studies is also discussed. The efficacy and pharmacokinetics of 50 antibiotics are discussed. Overall, most antibiotic classes exhibit biliary penetration that translates into clinical efficacy. Only seven antibiotics (amoxicillin, cefadroxil, cefoxitin, ertapenem, gentamicin, amikacin, and trimethoprim/sulfamethoxazole) had poor biliary penetration profiles. Three antibiotics (ceftibuten, ceftolozane/tazobactam, and doripenem) had positive clinical outcomes despite the lack of pharmacokinetic studies on their penetration into the biliary tract. Conflicting efficacy data were reported for ampicillin despite adequate biliary penetration, whereas conflicting pharmacokinetic data were reported with cefaclor and moxifloxacin. Even in the absence of supportive clinical studies, antibiotics with good biliary penetration profiles may have a place in the treatment of BTIs.

Dynamic Monitoring of sTREM-1 and Other Biomarkers in Acute Cholangitis

Background

Sepsis is a common complication of acute cholangitis (AC), which is associated with a high mortality rate. Our study is aimed at exploring the significance of white blood cell (WBC), C-reactive protein (CRP), procalcitonin (PCT), soluble triggering receptor expressed on myeloid cells 1 (sTREM-1), and temperature (T) alone or combined together in early identification and curative effect monitoring of AC with or without sepsis.

Methods

65 consecutive cases with AC and 76 control cases were enrolled. They were divided into three groups: Group A (AC with sepsis), Group B (AC without sepsis), and Group C (inpatients without AC or other infections). The levels of WBC, CRP, PCT, sTREM-1, and temperature were measured dynamically. The study was carried out and reported according to STARD 2015 reporting guidelines.

Results

CRP had the highest AUC to identify AC from individuals without AC or other infections (AUC 1.000, sensitivity 100.0%, specificity 100.0%, positive predictive value 100.0%, and negative predictive value 100.0%). Among various single indexes, PCT performed best (AUC 0.785, sensitivity 75.8%, specificity 72.2%, positive predictive value 68.7%, and negative predictive value 78.8%) to distinguish sepsis with AC, while different combinations of indexes did not perform better. From day 1 to day 5 of hospitalization, the levels of sTREM-1 in Group A were the highest, followed by Groups B and C (P < 0.05); on day 8, sTREM-1 levels in Groups A and B declined back to normal. However, other index levels among three groups still had a significant difference on day 10. Both in Groups A and B, sTREM-1 levels declined fast between day 1 and day 2 (P < 0.05).

Conclusions

CRP is the best biomarker to suggest infection here. PCT alone is sufficient enough to diagnose sepsis with AC. sTREM-1 is the best biomarker to monitor patients' response to antimicrobial therapy and biliary drainage.

Arabinofuranose-derived positron-emission tomography radiotracers for detection of pathogenic microorganisms

PURPOSE

Detection of bacteria-specific metabolism via positron emission tomography (PET) is an emerging strategy to image human pathogens, with dramatic implications for clinical practice. In silico and in vitro screening tools have recently been applied to this problem, with several monosaccharides including l-arabinose showing rapid accumulation in Escherichia coli and other organisms. Our goal for this study was to evaluate several synthetically viable arabinofuranose-derived 18 F analogs for their incorporation into pathogenic bacteria.

PROCEDURES

We synthesized four radiolabeled arabinofuranose-derived sugars: 2-deoxy-2-[18 F]fluoro-arabinofuranoses (d-2-18 F-AF and l-2-18 F-AF) and 5-deoxy-5-[18 F]fluoro-arabinofuranoses (d-5-18 F-AF and l-5-18 F-AF). The arabinofuranoses were synthesized from 18 F- via triflated, peracetylated precursors analogous to the most common radiosynthesis of 2-deoxy-2-[18 F]fluoro-d-glucose ([18 F]FDG). These radiotracers were screened for their uptake into E. coli and Staphylococcus aureus. Subsequently, the sensitivity of d-2-18 F-AF and l-2-18 F-AF to key human pathogens was investigated in vitro.

RESULTS

All 18 F radiotracer targets were synthesized in high radiochemical purity. In the screening study, d-2-18 F-AF and l-2-18 F-AF showed greater accumulation in E. coli than in S. aureus. When evaluated in a panel of pathologic microorganisms, both d-2-18 F-AF and l-2-18 F-AF demonstrated sensitivity to most gram-positive and gram-negative bacteria.

CONCLUSIONS

Arabinofuranose-derived 18 F PET radiotracers can be synthesized with high radiochemical purity. Our study showed absence of bacterial accumulation for 5-substitued analogs, a finding that may have mechanistic implications for related tracers. Both d-2-18 F-AF and l-2-18 F-AF showed sensitivity to most gram-negative and gram-positive organisms. Future in vivo studies will evaluate the diagnostic accuracy of these radiotracers in animal models of infection.

Clinical and microbiological characteristics of patients with biliary disease

BACKGROUND

Biliary diseases are common digestive system disorders which may combine with biliary tract infection such as cholecystitis or cholangitis. Thus, rapid identification of the bacteria and their antibiotic susceptibility profiles are crucial for reducing the mortality of patients with biliary tract infection.

AIM

To identify bacterial species and antibiotic susceptibility for antibacterial therapy and analyze bile cultivation risk factors for increasing detection rates.

METHODS

This retrospective study was conducted from July 2008 to July 2017. In total, 1339 bile samples which were collected during therapeutic endoscopic retrograde cholangiopan-creatography or percutaneous transhepatic cholangiodrainage or other biliary surgeries or biliary drainage were obtained to characterize pathogen spectra, antibiotic susceptibility, and clinical features. Clinical data including age, sex, comorbidities, clinical symptoms, protopathies, and history of biliary tract diseases and surgeries were collated from hospital medical records. Species identification and initial drug susceptibility were further identified by biochemical characterization using the VITEK 2 Compact test.

RESULTS

Positive microbiological findings were observed in 738 samples. The most frequently encountered strains were gram-negative bacteria (74.94%), including Escherichia coli (37.78%), Pseudomonas aeruginosa (8.96%), and Klebsiella pneumoniae (10.29%). Bile bacteria were largely sensitive to carbapenems, piperacillin/tazobactam, and gentamicin. Gram-negative strains had low susceptibility to ceftriaxone, quinolones and ampicillin. Almost the same micro-organisms were present in patients with malignant and benign diseases. The number of samples with Klebsiella pneumoniae in the bile culture were significantly different between patients with malignant and benign diseases (55 vs 30; P = 0.019). Age (P < 0.001), fever (P < 0.001), history of biliary tract diseases and surgeries (both P < 0.001), benign disease (P = 0.002), and the comorbidity chronic renal insufficiency (P = 0.007) affected the positive rates of the bile samples.

CONCLUSION

Gram-negative bacteria were the most commonly isolated biliary bacteria. We determined the major factors associated with positive detection rates. Microbiological analysis of bile samples allowed accurate antibiotic treatments.

Shortening antibiotic duration in the treatment of acute cholangitis: rationale and study protocol for an open-label randomized controlled trial

BACKGROUND

Antimicrobial therapy with appropriate biliary drainage is considered the standard of care for acute cholangitis, but the optimal duration of antimicrobial therapy remains unknown. Seven to 10 days of antimicrobial therapy are common for the treatment of acute cholangitis, but a recent retrospective cohort study suggested a shorter duration might be effective. A shorter duration of antimicrobial therapy can be beneficial in decreasing the length of hospital stay, improving patients' quality of life, decreasing adverse effects, and even contributing to a decrease in the occurrence of antimicrobial resistance.

METHODS/DESIGN

We will conduct a multi-centre, open-label, randomized, non-inferiority trial to compare short-course therapy (SCT) with conventional long-course therapy (LCT) in treating patients with acute cholangitis. SCT consists of 5-day intravenous antimicrobial therapy if the patients had clinical improvement, while at least 7 days of intravenous antibiotics will be provided to the LCT group. The primary outcome is clinical cure at 30 days after onset. Patients will be randomly assigned in an open-label fashion. A total sample size of 150 was estimated to provide a power of 80% with a one-sided α level of 2.5% and a non-inferiority margin of 10%.

DISCUSSION

This trial is expected to reveal whether SCT is non-inferior to conventional LCT or not, and may provide evidence that one can shorten the treatment duration for acute cholangitis for the benefit of patients.

TRIAL REGISTRATION

University Hospital Medical Information Network, UMIN000028382. Registered on 30 August 2017.

Definitive Cefazolin Therapy for Stabilized Adults with Community-Onset Escherichia coli, Klebsiella Species, and Proteus mirabilis Bacteremia: MIC Matters

Background: Cefazolin is in vitro active against wild isolates of Escherichia coli, Klebsiella species, and Proteus mirabilis (EKP), but clinical evidence supporting the contemporary susceptibility breakpoint issued by the Clinical and Laboratory Standards Institute (CLSI) are limited. Methods: Between 2010 and 2015, adults with monomicrobial community-onset EKP bacteremia with definitive cefazolin treatment (DCT) at two hospitals were analyzed. Cefazolin minimum inhibitory concentrations (MICs) were correlated with clinical outcomes, including primary (treatment failure of DCT) and secondary (30-day mortality after bacteremia onset, recurrent bacteremia, and mortality within 90 days after the end of DCT) outcomes. Results: Overall, 466 bacteremic episodes, including 340 (76.2%) episodes due to E. coli, 90 (20.2%) Klebsiella species, and 16 (3.6%) P. mirabilis isolates, were analyzed. The mean age of these patients was 67.8 years and female-predominated (68.4%). A crude 15- and 30-day mortality rate was 0.7% and 2.2%, respectively, and 11.2% experienced treatment failure of DCT. A significant linear-by-linear association of cefazolin MICs, with the rate of treatment failure, 30-day crude mortality, recurrent bacteremia or 90-day mortality after the DCT was present (all γ = 1.00, p = 0.01). After adjustment, the significant impact of cefazolin MIC breakpoint on treatment failure and 30-day crude mortality was most evident in 2 mg/L (>2 mg/L vs. ≤2 mg/L; adjusted hazard ratio, 3.69 and 4.79; p < 0.001 and 0.02, respectively). Conclusion: For stabilized patients with community-onset EKP bacteremia after appropriate empirical antimicrobial therapy, cefazolin might be recommended as a definitive therapy for cefazolin-susceptible EKP bacteremia, based on the contemporary CLSI breakpoint.

A prospective validation of Sepsis-3 guidelines in acute hepatobiliary sepsis: qSOFA lacks sensitivity and SIRS criteria lacks specificity (Cohort Study)

BACKGROUND

Since its introduction in 2016, the Sepsis-3 guidelines, with emphasis on the quick Sequential Organ Failure Assessment (qSOFA) score, have generated much debate and controversy. It is recognised that the new definitions require validation in specific clinical settings and have yet to be universally adopted. We aim to validate new Sepsis-3 guidelines in acute hepatobiliary infection.

MATERIAL AND METHODS

A prospective cohort of patients admitted with acute hepatobiliary infection from the emergency department from July 2016 to June 2017 was studied. The Systemic Inflammatory Response Syndrome (SIRS) criteria, SOFA and qSOFA scores were calculated and predictive performance evaluated with area under the receiver operating characteristic (AUROC) curves for predictive ability of these indices for critical care unit admission and morbidity.

RESULTS

124 patients with a median age of 64.5 years and majority males (n = 75, 60.5%) were admitted with acute hepatobiliary infection during the study period. Acute cholecystitis was the most common admission diagnosis (n = 83, 66.9%) and most patients were managed in general ward (n = 91, 73.3%) with median length of stay of 6 days (range 1-40). On multivariate analysis, diabetes mellitus (p = 0.003) predicted high dependency unit (HDU) admission, while age (p = 0.001), positive blood culture (p = 0.012), positive fluid culture (p = 0.015) and SOFA score (p = 0.002) predicted length of hospital stay. The sensitivity of SIRS in predicting HDU admission (60% vs. 4%), intensive care unit (ICU) admission (62.5% vs. 0%) and morbidity (66.7% vs. 0%) was higher than qSOFA score. The specificity of qSOFA in predicting HDU admission (100% vs. 49.5%), ICU admission (99.1% vs. 53.3%) and morbidity (99.2% vs. 47.9%) was higher than SIRS criteria.

CONCLUSION

The SIRS criteria has high sensitivity and the qSOFA score has high specificity in predicting outcomes of patients with acute hepatobiliary infection.