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

Outcomes in COVID-19 Patients with Acute Cholangitis: A Single-Center Retrospective Analysis

Background and Objectives: This study aimed to assess the impact of coronavirus disease 2019 (COVID-19) on patients with acute cholangitis (AC) by comparing outcomes, complications, and hospital stays in a tertiary Gastroenterology department. Materials and Methods: This retrospective observational cohort study was conducted in a tertiary gastroenterology department, collecting data from all AC and AC + COVID-19 patients between April 2020 and February 2022. Data included clinical and demographic information, COVID-19-specific details, acute cholangitis presentation, medical records, laboratory results, and interventions. AC was diagnosed using Tokyo Guidelines 2018 (TG18) criteria, with all patients undergoing bile culture sampling. Results: The study included 241 patients, 30 in the COVID group and 211 in the non-COVID group. The COVID group's mean age was significantly higher (74.3 vs. 67.3 years, p < 0.009). Abdominal pain was more common in the COVID group (90% vs. 70.6%, p < 0.025). Length of hospital stay was longer for COVID patients (13.5 vs. 7.9 days, p < 0.001). COVID patients had higher incidences of malignant causes of AC, with pancreatic cancer being the most common (30%). Pseudomonas spp. was significantly more prevalent in COVID patients (16.7% vs. 5.7%, p = 0.028). Conclusions: Our study results show that COVID-19 affected the duration of hospitalization for patients with AC. Furthermore, this study presents observations regarding the impact of COVID-19 on AC, revealing differences in microbial profiles.

Evaluating the frequency and risk factors of multidrug-resistant bacteria in biliary samples

Background and Objectives

This study aimed to evaluate the frequency of multidrug-resistant (MDR) bacteria in biliary samples, MDR-bacteria risk factors, and the relationship between MDR-bacteria positivity and some clinical outcomes.

Materials and Methods

The study was conducted between May 2018 and May 2023, including patients over the age of 18 who had positive culture results in biliary samples. The frequency of MDR-bacteria in biliary samples was evaluated. Risk factors for MDR bacteria were assessed using univariate and multivariate analyses. MDR and non-MDR groups were compared inappropriate empirical antibiotic treatment, total antibiotic treatment duration, length of stay, and in-hospital mortality.

Results

342 microorganisms were isolated from 202 patients. Escherichia coli was the most commonly (37.2%) isolated Gram-negative microorganism, and Enterococcus spp. was the most commonly (70.2%) isolated Gram-positive microorganism. The incidence of MDR microorganisms was 42.3%. Gastrointestinal malignancy (OR: 1.96; 95% CI, 1.03-3.71) and previous antibiotic use (OR: 2.26; 95% CI, 1.09-4.68) were independent risk factors for MDR-bacteria. In the MDR group, inappropriate empirical antibiotic treatment (56.6% vs. 41%, p = 0.091), total antibiotic treatment duration (13 vs. 8 days, p = 0.054), length of stay (24 vs. 15 days, p = 0.001), and in-hospital mortality (27.3% vs. 22.3%, p = 0.416) were higher compared to the non-MDR group.

Conclusion

MDR-bacteria positivity is associated with inappropriate antibiotic treatment, prolonged hospitalization, and increased mortality. Screening, antibiotic prophylaxis, and empirical treatment approaches should be carefully performed in patients with malignancy and recent antibiotic use, which are significant risk factors for MDR-bacteria.

Acute cholangitis due to Micrococcus lylae: First case report

Micrococcus lylae, a Gram-positive bacterium of the Micrococcaceae family, is considered an opportunistic microorganism with only a few reported cases of infection. In this report, we present a case of cholangitis caused by Micrococcus lylae in a 69-year-old woman with a medical history of type 2 diabetes and a cholecystectomy performed a decade ago. She was admitted to the gastroenterology department with symptoms indicative of acute cholangitis. Abdominal computed tomography and endoscopic ultrasound showed a consistent and symmetrical dilatation and thickening of the main bile duct, containing micro stones and a macro stone in the cystic duct stump. The patient received empirical antibiotic therapy based on ceftriaxone and metronidazole. She underwent ERCP with biliary endoscopic sphincterotomy and marginal biopsy, followed by balloon-assisted manipulation to facilitate bile release and collection of an intraoperative bile fluid sample for microbiological examination to identify the pathogen and guide the treatment adjustments. The microbiological examination demonstrated the exclusive presence of Micrococcus lylae. The patient's condition notably improved, marked by the normalization of inflammatory indicators. After three days, the patient was discharged in a stable condition, continuing the antibiotic regimen with the oral administration of ciprofloxacin and metronidazole. Jaundice resolved after one week, and liver function tests were completely normalized on follow-up at one month.

Risk factors for cefmetazole-non-susceptible bacteremia in acute cholangitis

INTRODUCTION

Cefmetazole (CMZ), an antibiotic with limited international distribution, is recommended by the Tokyo Guidelines 2018 (TG18) for non-severe cases of acute cholangitis (AC). However, the risk factors for CMZ-non-susceptible (CMZ-NS) bacteremia in AC remain unclear. Here, we aimed to investigate the risk factors for CMZ-NS bacteremia and evaluate mortality in patients with AC.

METHODS

This single-center, retrospective, observational study included all patients diagnosed with definite bacteremic AC, based on TG18, from April 2019 to March 2023. Risk factors for CMZ-NS bacteremia were analyzed by univariate, and age- and sex-adjusted, logistic regression analyses. Mortality was compared by cause of obstruction, CMZ-susceptible/CMZ-NS bacteremia, and initial treatment.

RESULTS

In total, 165 patients were enrolled. CMZ-NS bacteremia was diagnosed in 46 (27.9 %) patients. Histories of diabetes mellitus, hepato-biliary-pancreatic cancer, malignant biliary obstruction, and endoscopic sphincterotomy were identified as significant factors associated with the risk of CMZ-NS bacteremia. Thirteen patients died within 30 days of hospital admission. The mortality of patients with AC and malignant biliary obstruction was statistically higher than that of patients with bile duct stones. No patients with AC and bile duct stones died in the group with CMZ-NS bacteremia and inappropriate initial antibiotics.

CONCLUSIONS

In AC, a history of diabetes mellitus, hepato-biliary-pancreatic cancer, malignant biliary obstruction, and endoscopic sphincterotomy are associated with an increased risk of CMZ-NS bacteremia. Therefore, the choice of empiric therapy for AC should be based on the etiology and patient background, rather than on the severity.

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.

Fungal Infections Identified with Multiplex PCR in Severe COVID-19 Patients during Six Pandemic Waves

Background and Objectives: With an increasing number of severe COVID-19 cases presenting with secondary fungal infections, this study aimed to determine the prevalence of fungal co-infections in severe COVID-19 patients across the six waves, identify the most common fungal pathogens associated with severe COVID-19, and explore any potential links between patient characteristics, therapeutic strategies, and the prevalence and type of fungal infection. Materials and Methods: A retrospective analysis was conducted on severe COVID-19 patients admitted to the Infectious Diseases and Pulmonology Hospital, "Victor Babes", Romania, between March 2020 and August 2022. Samples were collected from respiratory specimens, blood, and urine, after which a standard nucleic acid extraction protocol was employed. Patients were divided into groups with and without fungal infections, identified using multiplex PCR. The groups were compared based on demographic data, comorbidities, pandemic wave number, and clinical outcomes. Results: Out of 288 patients, 96 (33.3%) had fungal infections, with Candida spp. being the most common. Patients with fungal infections had higher rates of obesity (35.4% vs. 21.4%, p = 0.010) and a higher Charlson comorbidity index (CCI > 2) (37.5% vs 25.0%, p = 0.027). Ventilator use was significantly higher in the fungal infection group (45.8% vs. 18.8%; p < 0.001), as was ICU admission (39.6% vs. 26.6%; p = 0.024) and mortality (32.3% vs 12.0%; p < 0.001). The distribution of different fungal species varied across the pandemic waves, with no statistical significance (p = 0.209). The mortality risk notably increased with the degree of drug resistance (OR for three or more drug resistances = 6.71, p < 0.001). The second, fourth, and fifth pandemic waves were significantly associated with higher mortality risk (OR = 3.72, 3.61, and 4.08, respectively, all p < 0.001). Aspergillus spp. and Mucor spp. infections were significantly associated with increased mortality risk (OR = 4.61 and 6.08, respectively, both p < 0.001). Conclusions: Our study indicates a significant presence of fungal co-infections among severe COVID-19 patients that is associated with increased morbidity and mortality, particularly in patients with drug-resistant infections. These findings underline the necessity for comprehensive diagnostic approaches and tailored treatment strategies in managing COVID-19 patients, especially during specific pandemic waves and in patients with particular fungal infections. Further research is required to understand the implications of these co-infections and their management.