Analysis of factors influencing the risk of secondary infection in patients colonized or infected with multidrug-resistant Gram-negative bacteria following hospitalization

We seek to investigate the multifaceted factors influencing secondary infections in patients with multidrug-resistant Gram-negative bacteria (MDR-GNB) colonization or infection post-hospitalization. A total of 100 patients with MDR-GNB colonization or infection were retrospectively reviewed, encompassing those admitted to both the general ward and intensive care unit of our hospital from August 2021 to December 2022. Patients were categorized into the control group (non-nosocomial infection, n = 56) and the observation group (nosocomial infection, n = 44) based on the occurrence of nosocomial infection during hospitalization. Clinical data were compared between the two groups, including the distribution and antibiotic sensitivity of MDR-GNB before nosocomial infection. Significant differences were observed between the two groups in terms of age, underlying diseases, immune status, length of stay, and invasive medical procedures (P < 0.05). The observation group also had fewer patients practicing optimized hygiene, strict isolation, and antibiotic control than the control group (P < 0.05). Factors influencing the risk of secondary infection after hospitalization in patients colonized or infected with MDR-GNB included patient age, underlying diseases, immune status, length of hospitalization, medical invasive procedures, optimized hygiene, strict isolation, and antibiotic control (P < 0.05). The length of hospitalization and treatment cost in the observation group were higher than those in the control group (P < 0.05). This study comprehensively analyzes the intricate mechanisms of secondary infections in patients with MDR-GNB infections post-hospitalization. Key factors influencing infection risk include patient age, underlying diseases, immune status, length of hospitalization, medical invasive procedures, optimized hygiene, strict isolation, and antibiotic control.

A Real-World Pharmacovigilance Study of Ceftazidime/Avibactam: Data Mining of the Food and Drug Administration Adverse Event Reporting System Database

Ceftazidime/avibactam (CAZ/AVI) is a combination of a well-known third-generation, broad-spectrum cephalosporin with a new beta-lactamase inhibitor that has been approved for the treatment of various infectious diseases (especially multidrug-resistant Gram-negative bacterial infections) by the Food and Drug Administration (FDA). The current study extensively assessed CAZ/AVI-related adverse events (AEs) in the real world through data mining of the FDA Adverse Event Reporting System (FAERS) database to better understand toxicities. The signals of CAZ/AVI-related AEs were quantified using disproportionality analyses, including the reporting odds ratio, the proportional reporting ratio, the Bayesian confidence propagation neural network, and the multi-item gamma Poisson shrinker algorithms. Out of 10,114,815 records retrieved from the FAERS database, 628 cases were identified, where CAZ/AVI was implicated as the primary suspect drug. A total of 61 preferred terms with significant disproportionality that simultaneously met the criteria of all four algorithms were retained. Several unexpected safety signals may also occur, including melena, hypernatremia, depressed level of consciousness, brain edema, petechiae, delirium, and shock hemorrhagic. The median onset time for AEs associated with CAZ/AVI was 4 days, with most cases occurring within 3 days after CAZ/AVI initiation.

The Etiological and Drug Resistance Characteristics of Multidrug-Resistant Pathogens in Patients Requiring Extracorporeal Membrane Oxygenation: A Retrospective Cohort Study

Purpose

Infections induced by multidrug-resistant (MDR) pathogens are one of the most common and serious complications in extracorporeal membrane oxygenation (ECMO) patients. However, there is currently little research about "ECMO and MDR bacteria". The purpose of our study was to clarify the epidemiological characteristics of MDR bacteria and provide references for empiric antibiotic treatments according to the drug susceptibility tests for ECMO patients.

Patients and Methods

There were 104 patients admitted to our department and receiving ECMO treatments between January 2014 and December 2022. Altogether, 61 veno-arterial ECMO (VA-ECMO) and 29 veno-venous ECMO (VV-ECMO) patients enrolled. The data on other intensive care unit (ICU) patients in our department in the same period are summarized.

Results

A total of 82 MDR bacteria were detected from ECMO patients, and most of these were MDR Gram-negative bacteria (MDR-GNB). There were also 5559 MDR-GNB collected from other patients in our department in the same period. We found that the distribution of MDR-GNB in ECMO patients was different from other critical patients. The proportion of Klebsiella pneumoniae (MDR-KP) in VV-ECMO patients was higher than other critical patients (35.1% and 21.3%, respectively). Moreover, the proportions of MDR Acinetobacter baumannii (MDR-AB) of VA-ECMO and VV-ECMO were higher than other critical patients (54.6%, 43.2% and 30.5%, respectively). In addition, MDR-AB and MDR-KP in ECMO patients exhibited higher percentages of drug resistance to possibly appropriate antibiotics for other critical patients, but showed better sensitivity to colistin.

Conclusion

Infections induced by MDR-GNB in ECMO patients were serious and exhibited higher degrees of drug resistance compared with other ICU patients. Colistin might be an option to consider if there is no medical contraindication. However, widespread use of broad spectrum antibiotics is something that should be discouraged, and alternative options are being explored.

Last Resort Antibiotics Costs and Reimbursement Analysis of Real-Life ICU Patients with Pneumonia Caused by Multidrug-Resistant Gram-Negative Bacteria in Germany

Multidrug-resistant Gram-negative bacteria (MDR-GNB) cause serious infections and aggravate disease progression. Last resort antibiotics are effective against MDR-GNB and are reimbursed by flat rates based on German diagnosis-related groups (G-DRG). From a hospital management perspective, this analysis compared hospital reimbursement for last resort antibiotics with their acquisition costs to outline potential funding gaps. Retrospective analyses based on medical charts and real-life reimbursement data included patients with pneumonia due to MDR-GNB treated in intensive care units (ICU) of a German tertiary care hospital (University Hospital Cologne) between January 2017 and December 2020. Drug-associated hospital reimbursement of G-DRG was compared with drug acquisition costs based on preliminarily approved last resort antibiotics (cefiderocol, ceftazidime-avibactam, ceftolozane-tazobactam, and imipenem-cilastatin-relebactam) according to label. Funding gaps were determined for the treatment of Enterobacterales, Pseudomonas aeruginosa, Acinetobacter baumannii, and mixed infections, respectively. Most of the 31 patients were infected with Enterobacterales (n = 15; 48.4%) and P. aeruginosa (n = 13; 41.9%). Drug-associated G-DRG reimbursement varied from 44.50 EUR (mixed infection of P. aeruginosa and Enterobacterales) to 2265.27 EUR (P. aeruginosa; mixed infection of P. aeruginosa and Enterobacterales). Drug acquisition costs ranged from 3284.40 EUR in ceftazidime-avibactam (minimum duration) to 15,827.01 EUR for imipenem-cilastatin-relebactam (maximum duration). Underfunding was found for all MDR-GNB, reaching from 1019.13 EUR (P. aeruginosa; mixed infection of P. aeruginosa and Enterobacterales) to 14,591.24 EUR (Enterobacterales). This analysis revealed the underfunding of last resort antibiotics in German hospital treatment. Insufficient reimbursement implies less research in this field, leading to a more frequent use of inappropriate antibiotics. The cycle closes as this contributes to the development of multi-drug resistant bacteria.

Multidrug-Resistant Gram-Negative Bacteria: Infection Prevention and Control Update

Multidrug-resistant gram-negative bacteria (MDR-GNB) pose one of the greatest challenges to health care today because of their propensity for human-to-human transmission and lack of therapeutic options. Containing the spread of MDR-GNB is challenging, and the application of multifaceted infection control bundles during an evolving outbreak makes it difficult to measure the relative impact of each measure. This article will review the utility of various infection control measures in containing the spread of various MDR-GNB and will provide the supporting evidence for these interventions.

Clinical characteristics and outcomes of patients with multidrug-resistant Gram-negative bacterial infections treated with ceftazidime/avibactam

OBJECTIVES

The aim of this study was to investigate the clinical characteristics and outcomes of patients with infections caused by multidrug-resistant Gram-negative bacteria (MDR-GNB) treated with ceftazidime/avibactam (CAZ/AVI) during the period September 2019 to June 2020 since CAZ/AVI had been marketed in China.

METHODS

A total of 20 MDR-GNB-infected patients were retrospectively identified using the electronic medical record system in West China Hospital.

RESULTS

The mean age of the 20 patients was 54.5 ± 17.37 years and 14 (70%) were male. Pneumonia (n = 12; 60%), complicated intra-abdominal infection (n = 10; 50%), and bloodstream infection (n = 7; 35%) were the most common infection sources. Klebsiella pneumoniae (55% 18/33) was the predominant pathogen. The 14-day clinical cure rate was 45%. The 14-day and 30-day mortality rates were 25% and 55%, respectively. No significant difference was found in 30-day mortality between treatment with CAZ/AVI monotherapy and combination regimens (P > 0.05). Three patients suffered from adverse drug reactions such as diarrhoea.

CONCLUSION

No significant difference was found between the effectiveness of CAZ/AVI in the clinical failure and cure groups as salvage treatment of MDR-GNB infection.

Acquisition of MDR-GNB in hospital settings: a systematic review and meta-analysis focusing on ESBL-E

INTRODUCTION

Extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E) and other multi-drug-resistant Gram-negative bacteria (MDR-GNB) have disseminated globally since their discovery in the late 20^th century. Various infection prevention and control measures are in place to prevent nosocomial transmission of these organisms, but their efficacy remains disputed. New literature has emerged in recent years providing further evidence which can be used to formulate effective strategies to tackle this issue in the future.

METHODS

A systematic review was performed to characterize the prevalence of colonization of multi-drug-resistant organisms and subsequent acquisition of these organisms within hospital settings. A meta-analysis was performed to characterize the prevalence and acquisition of ESBL-E in Europe and North America.

RESULTS

Twenty-eight studies fulfilled the inclusion criteria. Escherichia coli formed the main burden of MDR-GNB colonization worldwide. Patient-to-patient transmission of ESBL-E was found to be rare, but increased transmissibility of Klebsiella pneumoniae was described over E. coli. Within European and North American healthcare settings, a meta-analysis of eight studies identified a pooled prevalence of ESBL-E on admission to hospital of 7.91% and an acquisition rate of 3.73%.

DISCUSSION

Low prevalence at the point of hospital admission and insufficient evidence of patient-to-patient transmission suggests that infection prevention and control measures such as universal surveillance screening and single-room isolation are unlikely to be practical or effective interventions in reducing the overall burden of ESBL-E in hospitals, in line with current European guidelines. Instead, it is argued that efforts should be placed on controlling the spread of these organisms and other MDR-GNB in the community, predominantly long-term care facilities.

How to manage KPC infections

Carbapenemase-producing Enterobacteriaceae represent an increasing global threat worldwide and Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-KP) has become one of the most important contemporary pathogens, especially in endemic areas. Risk stratification and rapid diagnostics laboratory workflows are of paramount importance and indication for therapy of KPC-KP infection must be individualized according to the baseline characteristics of the patient and severity of infection. The optimal treatment of infection because of KPC-KP organisms is uncertain and antibiotic options are limited. The knowledge of the patient's pathophysiology, infection site, and application of the pharmacokinetic/pharmacodynamic principles on the basis of minimum inhibitory concentration (MIC) has progressively gained major relevance. Combination therapies including high-dose meropenem, colistin, fosfomycin, tigecycline, and aminoglycosides are widely used, with suboptimal results. In the past few years, new antimicrobials targeting KPC-KP have been developed and are now at various stages of clinical research. However, their optimal use should be guaranteed in the long term for delaying, as much as possible, the emergence of resistance. Strict infection control measures remain necessary. The aim of this review is to discuss the challenges in the management and treatment of patients with infections because KPC-KP and provide an expert opinion.

Prevalence of multidrug-resistant Gram-negative bacteria cases at admission in a multispeciality hospital

OBJECTIVES

The prevalence of drug-resistant cases is increasing globally. The present study aimed to investigate the prevalence of cases of blood culture positive for multidrug-resistant Gram-negative bacteria (MDR-GNB) at the time of admission, i.e. within 24h of admission to hospital from primary or secondary care centres.

METHODS

This record-based retrospective cross-sectional study was designed to analyze MDR-GNB-positive cases at Fortis Hospital, Mumbai, India. Fortis Hospital is a 500-bed referral tertiary care centre. An increase of MDR-GNB was seen from January 2012 to June 2014 in the hospital. A retrospective analysis of blood culture GNB-positive samples was performed to evaluate MDR-GNB-positive cases at admission.

RESULTS

The total number of positive blood cultures in January to December 2012, January to December 2013 and January to June 2014 were 221, 236 and 116, respectively, with 77.83%, 79.66% and 69.83% GNB-positive. Total MDR-GNB-positive cases were 26.16%, 32.98% and 33.33%, respectively, and amongst these MDR-GNB, 22%, 32% and 37% where positive at time of admission to the hospital. The MDR-GNB were Escherichia coli, Klebsiella, Acinetobacter, Pseudomonas and Enterobacter.

CONCLUSION

MDR-GNB blood cultures positive at admission rose from January 2012 to June 2014 and hence there is an urgent need for possible contact isolation of all patients coming from primary and secondary to tertiary health care centres which should be made compulsory until screening rules out MDR-GNB to prevent spread of MDR organisms in the hospital.

Transmission of multidrug-resistant Gram-negative bacteria from colonized mothers to their infants: a systematic review and meta-analysis

BACKGROUND

Neonatal sepsis remains a leading cause of neonatal mortality. Maternal bacterial colonization plays a major role in transmission to the infant, with potential for subsequent development of neonatal sepsis with maternally derived strains.

AIM

To review the molecular evidence supporting transmission of multidrug-resistant Gram-negative bacteria (MDR-GNB) from colonized mothers to their infants and the risk factors for MDR-GNB transmission.

METHODS

PubMed and Scopus were searched for studies investigating the mechanisms, risk factors for and/or scale of transmission of MDR-GNB from colonized mothers to their infants. Random effects meta-analyses were performed to determine pooled proportions of MDR-GNB transmission and the neonatal outcomes of transmission.

FINDINGS

Eight studies were included in the narrative description and six in the meta-analysis. Five studies used pulsed-field gel electrophoresis to assess relatedness of isolates from colonized mothers and their infants. Pooled proportion of MDR-GNB transmission from colonized mothers to their infants was 27% (95% confidence interval (CI): 8-47%). Extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae were the most frequently studied MDR-GNB pathogens transmitted between mother-infant pairs. Following mother-to-infant transmission of an MDR-GNB pathogen, the pooled proportion for the outcome of neonatal colonization was 19% (95% CI: 3-35%).

CONCLUSION

This systematic review strongly supports MDR and/or ESBL Enterobacteriaceae transmission from colonized mothers to their infants, with subsequent infant colonization. The risk factors contributing to transmission of MDR-GNB between colonized mothers and their infants warrants further research.

Infection with gram-negative bacteria among children in a tertiary pediatric hospital in Egypt

BACKGROUND

Patients in pediatric intensive care units (PICUs) are susceptible to infections with gram-negative bacteria (GNB).

METHODS

A prospective observational study was conducted in 2 PICUs at Cairo University Hospitals to determine the incidence and outcome of GNB infections over 1 year. Variables of interest included age, gender, isolated organism, susceptibility to antibiotics, and final outcome.

RESULTS

During the study period, 1420 patients were admitted to the PICU; of these, 291 developed GNB infections. The median age of the studied GNB patients was 50 months (interquartile range [IQR], 22-80 months). The mortality rate was 37.1%. Organisms were isolated from blood in the majority (86.6%) of patients, with Klebsiella (36.0%) being the most frequently isolated organism. Among patients with GNB infection, 235 patients, one had a multidrug-resistant (MDR) infection. The length of hospital stay was statistically significantly longer in the MDR group (25 days; IQR, 20-30) than in the non-MDR group (15 days; IQR, 10-20) (P < .01). Mortality was similar in both groups (37.4% vs 35.7% in the MDR and non-MDR groups, respectively; P = .88).

CONCLUSION

This study highlights high rates of pediatric MDR-GNB infections and emphasizes the need for a continuous surveillance system in the management of these critically ill children.