Management of carbapenem-resistant Acinetobacter baumannii epidemic in an intensive care unit using multifaceted intervention strategy

Carbapenem-resistant Acinetobacter baumannii: A challenge in the intensive care unit

Carbapenem-resistant Acinetobacter baumannii (CRAB) has become one of the leading causes of healthcare-associated infections globally, particularly in intensive care units (ICUs). Cross-transmission of microorganisms between patients and the hospital environment may play a crucial role in ICU-acquired CRAB colonization and infection. The control and treatment of CRAB infection in ICUs have been recognized as a global challenge because of its multiple-drug resistance. The main concern is that CRAB infections can be disastrous for ICU patients if currently existing limited therapeutic alternatives fail in the future. Therefore, the colonization, infection, transmission, and resistance mechanisms of CRAB in ICUs need to be systematically studied. To provide a basis for prevention and control countermeasures for CRAB infection in ICUs, we present an overview of research on CRAB in ICUs, summarize clinical infections and environmental reservoirs, discuss the drug resistance mechanism and homology of CRAB in ICUs, and evaluate contemporary treatment and control strategies.

Control of Healthcare-Associated Carbapenem-Resistant Acinetobacter baumannii by Enhancement of Infection Control Measures

Antimicrobial stewardship and infection control measures are equally important in the control of antimicrobial-resistant organisms. We conducted a retrospective analysis of the incidence rate of hospital-onset carbapenem-resistant Acinetobacter baumannii (CRAB) infection (per 1000 patient days) in the Queen Mary Hospital, a 1700-bed, university-affiliated teaching hospital, from period 1 (1 January 2007 to 31 December 2013) to period 2 (1 January 2014 to 31 December 2019), where enhanced infection control measures, including directly observed hand hygiene before meal and medication rounds to conscious patients, and the priority use of single room isolation, were implemented during period 2. This study aimed to investigate the association between enhanced infection control measures and changes in the trend in the incidence rate of hospital-onset CRAB infection. Antimicrobial consumption (defined daily dose per 1000 patient days) was monitored. Interrupted time series, in particular segmented Poisson regression, was used. The hospital-onset CRAB infection increased by 21.3% per year [relative risk (RR): 1.213, 95% confidence interval (CI): 1.162−1.266, p < 0.001], whereas the consumption of the extended spectrum betalactam-betalactamase inhibitor (BLBI) combination and cephalosporins increased by 11.2% per year (RR: 1.112, 95% CI: 1.102−1.122, p < 0.001) and 4.2% per year (RR: 1.042, 95% CI: 1.028−1.056, p < 0.001), respectively, in period 1. With enhanced infection control measures, the hospital-onset CRAB infection decreased by 9.8% per year (RR: 0.902, 95% CI: 0.854−0.953, p < 0.001), whereas the consumption of the extended spectrum BLBI combination and cephalosporins increased by 3.8% per year (RR: 1.038, 95% CI: 1.033−1.044, p < 0.001) and 7.6% per year (RR: 1.076, 95% CI: 1.056−1.097, p < 0.001), respectively, in period 2. The consumption of carbapenems increased by 8.4% per year (RR: 1.84, 95% CI: 1.073−1.094, p < 0.001) in both period 1 and period 2. The control of healthcare-associated CRAB could be achieved by infection control measures with an emphasis on directly observed hand hygiene, despite an increasing trend of antimicrobial consumption.

Identifying Targets for Antibiotic Use for the Management of Carbapenem-Resistant Acinetobacter baumannii (CRAb) in Hospitals-A Multi-Centre Nonlinear Time-Series Study

Solutions are needed to inform antimicrobial stewardship (AMS) regarding balancing the access to effective antimicrobials with the need to control antimicrobial resistance. Theoretical and mathematical models suggest a non-linear relationship between antibiotic use and resistance, indicating the existence of thresholds of antibiotic use beyond which resistance would be triggered. It is anticipated that thresholds may vary across populations depending on host, environment, and organism factors. Further research is needed to evaluate thresholds in antibiotic use for a specific pathogen across different settings. The objective of this study is to identify thresholds of population antibiotic use associated with the incidence of carbapenem-resistant Acinetobacter baumannii (CRAb) across six hospital sites in Oman. The study was an ecological, multi-centre evaluation that involved collecting historical antibiotic use and CRAb incidence over the period from January 2015 to December 2019. By using non-linear time-series analysis, we identified different thresholds in the use of third-generation cephalosporins, piperacillin-tazobactam, aminoglycoside, and fluoroquinolones across participating hospitals. The identification of different thresholds emphasises the need for tailored analysis based on modelling data from each hospital. The determined thresholds can be used to set targets for each hospital AMS, providing a balance between access to these antibiotics versus controlling CRAb incidence.

Urgent need for novel antibiotics in Republic of Korea to combat multidrug-resistant bacteria

Multidrug resistance in bacteria is an important issue and is increasing in frequency worldwide because of the limitations of therapeutic agents. From 2010 to 2019, 14 new systemic antibiotics received regulatory approval in the United States. However, few new antibiotics have been introduced in Republic of Korea to combat multidrug-resistant pathogens. Here, we introduce six novel antibiotics for Gram-positive bacteria and five for Gram-negative bacteria approved by the United States Food and Drug Administration and the European Medicines Agency from 2009 to October 2021, and recommend that they be approved for use in Republic of Korea at the earliest possible date.

Challenges for adherence to bacterial resistance actions in large hospitals

OBJECTIVES

to identify the challenges to actions to contain bacterial resistance.

METHODS

cross-sectional study, carried out in 30 large-sized hospitals in Minas Gerais, from 2018 to 2019. The professionals were interviewed, and the environment and actions to prevent bacterial resistance were observed.

RESULTS

regarding the knowledge of health care professionals about the measures of bacterial resistance prevention, 78.3% did not correctly describe the five moments of hand hygiene, and 76.6% did not correctly describe the measures to control bacterial resistance. The simple hygiene of hands, followed by alcohol rubbing was predominant (48.3%) among workers, and soap dispensers were next to alcohol dispensers in 58.3% of the nursing stations in care units.

CONCLUSIONS

the insufficient knowledge from the professionals, which is a failure related to the physical structure and to personal protection equipment, are factors that difficult the adherence to measures to contain bacterial resistance in hospitals.

Successful Incidences of Controlling Multidrug-Resistant, Extensively Drug-Resistant, and Nosocomial Infection Acinetobacter baumannii Using Antibiotic Stewardship, Infection Control Programs, and Environmental Cleaning at a Chinese University Hospital

Objective

We estimated the efficacy of antimicrobial stewardship (AMS), infection control programs (ICP), and environmental cleaning (ENC) for controlling the resistance of Acinetobacter baumannii (AB) and controlling the incidence of multidrug-resistant AB (MDRAB), extensively drug-resistant AB (XDRAB), and nosocomial infection AB in the ICU (NIAB-ICU) at a university hospital.

Methods

The intervention included 4-year AMS+ICP and 3-year AMS+ICP+ENC between January 2012 and December 2019.

Results

A total of 2636 AB isolates were collected totally, and 64.98% of AB isolates were MDR and 29.97% were XDR. Preintervention and postintervention incidences of MDRAB, XDRAB, and NIAB-ICU by AMS+ICP measures ranged from 84.96% to 71.98%, 41.96% to 33.13%, and 45.6% to 38%, respectively. However, all of them were not statistically changed (P=0.085, 0.072, 0.061, separately). The preintervention and postintervention incidences of MDRAB, XDRAB, and NIAB-ICU by AMS+ICP+ENC measures ranged from 71.98% to 36.55%, 33.13% to 19.88%, and 38% to 22.5%, respectively. Statistically significant declines were observed (P=0.016, 0.041, 0.032, separately). The defined daily doses (DDD) per 1000 patient-days (PD) decreased from 45±3.3 to 30.81±1.5 per 1000 PD across from 2012 to 2019, and a statistical decline was seen (P=0.01). Concurrently, the alcohol-based hand gel (ABHG) consumption per 1000 PD increased from 0.6±0.05 L to 12.5±2.3 L per 1000 PD, and a statistical increase was observed (P=0.0001). A statistically positive correlation was revealed between the DDD and incidence of MDRAB, XDRAB, and NIAB-ICU (r=0.905 and p=0.002; r=0.939 and p=0.001; r=0.956 and p=0.0002; respectively). Simultaneously, a statistically negative correlation was showed between the ABHG and incidence of MDRAB, XDRAB, and NIAB-ICU (r=-0.858 and p=0.006; r=-0.888 and p=0.003; r=-0.882 and p=0.004, separately).

Conclusion

The AMS, ICP, and ENC may be one of the most effective and best measures to address the increasing incidence of MDRAB, XDRAB, and NIAB-ICU currently.

Control of a hospital-wide outbreak of carbapenem-resistant Acinetobacter baumannii (CRAB) using the Israeli national carbapenem-resistant Enterobacteriaceae (CRE) guidelines as a model

OBJECTIVE

To study the effect of implementing the Israeli national carbapenem-resistant enterobacteriaceae (CRE) guidelines on controlling a hospital-wide outbreak of Acinetobacter baumannii (CRAB).

DESIGN

A before-and-after study from 2014 to 2018.

SETTING

A 740-bed, secondary-care hospital in central Israel.

INTERVENTION

Acquisition of CRAB was defined as a positive culture taken at least 48 hours after admission or a positive sample identified upon admission in a patient who had been readmitted within 30 days after discharge from our institution. The intervention included maintaining a case registry of all CRAB patients, cohorting patients under strict contact isolation, using dedicated nursing staff and equipment, rigorous cleaning, education and close monitoring of hospital staff, and involvement of hospital management.

RESULTS

In total, 210 patients were identified with hospital-acquired CRAB: 141 before the intervention and 69 after the intervention. CRAB acquisition rates decreased by 77%, from 1.3 per 1,000 admissions before the intervention (2014-2015) to 0.3 per 1,000 admissions after the intervention (2016-2018) (P < .001). The decrease in acquisitions was observed hospital-wide, year by year (P for trend, <.001). In 2018, only 7 new acquisitions were detected in internal medicine wards (P = .058) and none in the ICUs (P = .006).

CONCLUSIONS

A structured intervention based on the Israeli CRE management guidelines was successful in controlling a hospital-wide CRAB outbreak.

Effect of chlorhexidine bathing on colonization or infection with Acinetobacter baumannii: a systematic review and meta-analysis

Healthcare-associated infections (HAIs) caused by multi-drug-resistant Gram-negative bacteria (MDRGNB) have increased prevalence in intensive care units (ICUs). A common strategy to prevent HAIs is bathing patients with chlorhexidine gluconate (CHG). However, the effectiveness of CHG bathing against multidrug-resistant Acinetobacter baumannii (MDRAB) is still controversial. The aim of this study was to perform a systematic review and meta-analysis of the effectiveness of CHG bathing on Acinetobacter baumannii colonization and infection in the ICU setting. A systematic literature search of PubMed, EMBASE, Web of Science and CINAHL was performed from inception through to June 2018. Randomized controlled trials (RCTs), pre-post studies, or interrupted time series (ITS) studies were included. The numbers of patients with/without colonization or infection of A. baumannii in the experimental or control groups were extracted from each study. Quality assessment was performed by the related instruments of National Institute of Health. Pooled risk ratios (RRs) were calculated using the random-effects model. One RCT and 12 pre-post or ITS studies comprising 18,217 patients were included, of which 8069 were in the CHG bathing arm and 9051 in the control arm. CHG bathing was associated with a reduced colonization of A. baumannii (RR, 0.66; 95% confidence interval: 0.57-0.77; P<0.001). Chlorhexidine at 4% showed a better effect than 2% chlorhexidine (meta-regression P=0.044). CHG bathing was associated with a non-significant reduction of infection (pooled RR 0.41, 95% CI: 0.13-1.25). This study suggests that CHG bathing significantly reduces colonization of A. baumannii in the ICU setting. However, more trials are needed to confirm whether CHG bathing can reduce infections with A. baumannii.

Effectiveness of daily chlorhexidine bathing for reducing gram-negative infections: A meta-analysis

OBJECTIVE

Multiple studies have demonstrated that daily chlorhexidine gluconate (CHG) bathing is associated with a significant reduction in infections caused by gram-positive pathogens. However, there are limited data on the effectiveness of daily CHG bathing on gram-negative infections. The aim of this study was to determine whether daily CHG bathing is effective in reducing the rate of gram-negative infections in adult intensive care unit (ICU) patients.

DESIGN

We searched MEDLINE and 3 other databases for original studies comparing daily bathing with and without CHG. Two investigators extracted data independently on baseline characteristics, study design, form and concentration of CHG, incidence, and outcomes related to gram-negative infections. Data were combined using a random-effects model and pooled relative risk ratios (RRs), and 95% confidence intervals (CIs) were derived.

RESULTS

In total, 15 studies (n = 34,895 patients) met inclusion criteria. Daily CHG bathing was not significantly associated with a lower risk of gram-negative infections compared with controls (RR, 0.89; 95% CI, 0.73-1.08; P = .24). Subgroup analysis demonstrated that daily CHG bathing was not effective for reducing the risk of gram-negative infections caused by Acinetobacter, Escherichia coli, Klebsiella, Enterobacter, or Pseudomonas spp.

CONCLUSIONS

The use of daily CHG bathing was not associated with a lower risk of gram-negative infections. Further, better designed trials with adequate power and with gram-negative infections as the primary end point are needed.