Clinical epidemiology and outcomes of biliary tract infections caused by Klebsiella pneumoniae

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.

Intensive care unit-acquired pneumonia caused by Klebsiella pneumoniae in China: Risk factors and prediction model of mortality

Intensive care unit (ICU)-acquired pneumonia (ICUAP) is a major concern owing to its associated high mortality rate. Few studies have focused on ICUAP caused by Klebsiella pneumoniae (KP). This study aimed to investigate the risk factors for ICUAP-associated death due to KP and to develop a mortality prediction model. Patients with KP-associated ICUAP at Renji Hospital were enrolled from January 2012 to December 2017. The patients were registered from the ICU units of the Surgery, Gynecology and Obstetrics, Neurosurgery, Emergency and Geriatric Departments, and were followed for 30 days. A multivariate analysis was performed to analyze the differences between 30-day survivors and nonsurvivors, and to determine the independent risk factors. Receiver operator characteristic (ROC) curves were also used to determine the predictive power of the model. Among the 285 patients with KP-associated ICUAP, the median age was 70.55 years, and 61.6% were men. Fifty patients died. The nonsurvivors had a lower Glasgow coma score (GCS), platelet count, and albumin concentrations, but higher lactate concentrations, than the survivors. The nonsurvivors were also more likely to be admitted to the ICU for respiratory failure and surgery, and they received less appropriate empirical antimicrobial therapy than the survivors. A lower GCS (odds ratio [OR] = 0.836, 95% confidence interval [CI]: 0.770-0.907), lower albumin concentrations (OR = 0.836, 95% CI: 0.770-0.907), higher lactate concentrations (OR = 1.167, 95% CI: 1.0013-1.344) and inappropriate empirical treatment (OR = 2.559, 95% CI: 1.080-6.065) were independent risk factors for mortality in patients with KP-associated ICUAP. ROC curve analysis showed that the risk of death was higher in patients with 2 or more independent risk factors. The predictive model was effective, with an area under the ROC curve of 0.823 (95% CI: 0.773-0.865). The number of independent risk factors is positively correlated with the risk of death. Our model shows excellent predictive performance.

Epidemiology of patients with central nervous system infections, mainly neurosurgical patients: a retrospective study from 2012 to 2019 in a teaching hospital in China

BACKGROUND

Central nervous system (CNS) infections are relatively rare but are associated with high mortality worldwide. Empirical antimicrobial therapy is crucial for the survival of patients with CNS infections, and should be based on the knowledge of the pathogen distribution and antibiotic sensitivities. The aim of this study was to investigate the features of pathogens in patients with CNS infections in North China and evaluate the risk factors for mortality and multi-drug-resistant (MDR) bacterial infections.

METHODS

A retrospective study was conducted with patients with positive cerebrospinal fluid (CSF) cultures in a teaching hospital from January 2012 to December 2019. The following data were collected: demographic characteristics, laboratory data, causative organisms and antimicrobial sensitivity results. Data were analyzed with SPSS 16.0. Univariate analysis and binary logistic regression analyses were performed to identify the risk factors for mortality and MDR bacterial infections.

RESULTS

A total of 72 patients were diagnosed with CNS infections, and 86 isolates were identified. The proportions of Gram-positive bacteria, Gram-negative bacteria and fungi were 59.3, 30.2 and 10.5%, respectively. The predominant Gram-positive bacteria was Coagulase-negative Staphylococci. Acinetobacter baumannii, Escherichia coli and Klebsiella spp. were the predominant Gram-negative bacteria. Compared to 2012-2015 years, the proportion of Gram-negative bacteria increased markedly during 2016-2019 years. Coagulase-negative Staphylococci, Streptococcus pneumoniae and Enterococcus faecium had 100% sensitivity to vancomycin, teicoplanin and linezolid. Acinetobacter baumannii and Klebsiella pneumoniae were 100% sensitive to tigecycline. Escherichia coli had 100% sensitivity to amikacin, meropenem and imipenem. The overall mortality rate in the 72 patients was 30.6%. In multivariate analysis, age > 50 years, pulmonary infections and CSF glucose level < the normal value were associated with poor outcomes. CSF adenosine deaminase level > the normal value and the presence of external ventricular drainage/lumbar cistern drainage were associated with MDR bacterial infections.

CONCLUSIONS

The mortality rate due to CNS infections reached 30.6% in our study. The proportion of Gram-negative bacteria has increased markedly in recent years. We should give particular attention to patients with risk factors for mortality and MDR bacterial infections mentioned above.