Carbapenem-resistant Enterobacteriaceae on a cardiac surgery intensive care unit: successful measures for infection control

Risk factors of carbapenemase-producing Enterobacterales acquisition among adult intensive care unit patients at a Kentucky Academic Medical Center

Background

Acquisition of carbapenemase-producing carbapenem-resistant Enterobacterales (CP-CRE) are associated with negative health outcomes. Our adult intensive care unit (ICU) population has experienced low levels of CP-CRE acquisition; however, specific risk factors for this population at our medical facility have not been studied.

Aims

To identify risk factors of CP-CRE acquisition and describe CP-CRE epidemiology among adult ICU patients at our medical facility.

Methods

A retrospective cohort study was performed at a Kentucky Academic Medical Center. Surveillance specimens were collected at admission and weekly thereafter to identify CP-CRE colonization. Clinical data were extracted from patient medical records. Cases were defined as those who tested positive for CP-CRE on ICU admission day 3 or greater. Risk of CP-CRE acquisition was calculated using Modified Poisson regression.

Findings

Independent risk factors of CP-CRE acquisition included administration of enteral tube feeds (risk ratio [RR], 4.46; 95% confidence interval [CI], 1.74-11.43); diagnosis of Clostridioides difficile enterocolitis (RR, 3.51; 95% CI, 1.27-9.68), pressure ulcer (RR, 3.48; 95% CI, 1.91-6.36), and morbid obesity (RR, 2.10; 95% CI, 1.12-3.95); having a drainage tube (RR, 2.63; 95% CI, 1.38-4.98); admission to a medical ICU (RR, 2.39; 95% CI, 1.32-4.35); 90-day use of a carbapenem (RR, 2.27; 95% CI, 1.21-4.26); and dialysis procedure (RR, 2.22; 95% CI, 1.15-4.27).

Conclusion

Most CP-CRE risk factors were associated with alteration of colon microbiota and/or invasive procedures/devices. These results will assist in creating a more targeted CP-CRE active surveillance system and highlight areas for infection prevention intervention.

Application Effect of Transparent Supervision Based on Informatization in Prevention and Control of Carbapenem-Resistant Klebsiella pneumoniae Nosocomial Infection

Objective

To explore the effect of transparent supervision model on the prevention and control of carbapenem-resistant Klebsiella pneumoniae (CRKP) nosocomial infection and the value of the autoregressive integrated moving average (ARIMA) model in predicting the incidence of CRKP infection.

Methods

A total of 46,873 inpatients from Jiawang District People's Hospital of Xuzhou between January 2019 and December 2019 (prior to COVID-19 prevention and control) were selected as the preintervention group and 45,217 inpatients from January 2020 to December 2020 (after the COVID-19 prevention and control) as the postintervention group. We performed transparent supervision on CRKP patients detected by the real-time monitoring system for nosocomial infection. Incidence and detection rate of CRKP, utilization rate of special grade hydrocarbon enzyme alkene antibiotics, hand hygiene compliance rate, qualified rate of ATP tests on surface of environmental objects, and execution rate of CRKP core prevention and control were compared between the two groups.

Results

Transparent supervision of CRKP-infected patients was conducted daily from January to December 2020, which resulted in the following: (a) the infection rate of CRKP decreased in a fluctuating manner, and the actual value of hydrocarbon alkene use rate was basically the same as the predicted value with an overall decreasing trend; (b) after the intervention, hand hygiene compliance rate increased from 53.30% to 70.24% (P < 0.001) and the ATP qualified rate increased from 53.77% to 92.24% (P < 0.001); (c) the fitted value of the ARIMA model was in good agreement with the actual value. The incidence of CRKP infection and the utilization rate of carbene antibiotics were also in good agreement with the predicted value. The average relative errors were 11% and 10.78%.

Conclusions

During the COVID-19 outbreak in 2020, the ARIMA model effectively fit and predicted the CRKP infection rate, thereby providing scientific guidance for the prevention and control of CRKP infection. In addition, the transparent supervision intervention model improved the hand hygiene compliance and environmental hygiene qualification rates of medical staff, effectively reducing CRKP cross-infection in the hospital.

The importance of active surveillance of carbapenem-resistant Enterobacterales (CRE) in colonization rates in critically ill patients

OBJECTIVE

This study aimed to demonstrate the importance of active carbapenem-resistant Enterobacterales (CRE) surveillance and evaluate the prevalence of invasive infections, risk factors, and mortality risk in CRE-colonized patients.

METHODS

Retrospective cohort study analyzing 1,920 patients identified using an active CRE surveillance protocol, admitted to an adult intensive care unit in southeastern Brazil from January 2014 to December 2018.

RESULTS

There were 297 (15.47%) CRE colonized patients, with one colonized for every six control patients. CRE-colonized patients demonstrated an increased chance of infection (odds ratio [OR] 7.967, p < 0.001). Overall, 20.54% of the colonized patients presented invasive infection (81.96% due to Klebsiella pneumoniae). The colonization and infection ratio demonstrated the important role of the active CRE surveillance protocol. There were identified multiple risk factors for CRE colonization, including long-term mechanical ventilation (OR 1.624, p = 0.019) and previous exposure to aminopenicillins (OR 5.204, p < 0.001), carbapenems (OR 3.703, p = 0.017), cephalosporins (OR 12.036, p < 0.001), and fluoroquinolones (OR 5.238, p = 0.012). The mortality risk was significantly higher among colonized (OR 2.356, p < 0.001) and colonized-infected (OR 2.000, p = 0.009) patients and in those with Enterobacter cloacae colonization (OR 5.173, p < 0,001) and previous aminopenicillins exposure (OR 3.452, p = 0.007).

CONCLUSIONS

Early detection of CRE colonization through screening testing proved to be an important tool to control CRE spread. However, observation over the years has shown no effective control of colonization and infection. The prevalence rates of CRE colonization and colonization-infection were high, as were the mortality rates. In conclusion, an active CRE surveillance protocol is essential, but its impact depends on the effective implementation of preventive measures and feedback between team members.

Phenotypic and molecular evaluation of biofilm formation in Klebsiella pneumoniae carbapenemase (KPC) isolates obtained from a hospital of Pelotas, RS, Brazil

Introduction. A significant cause of mortality in the intensive care unit (ICU) is multidrug-resistant (MDR) Gram-negative bacteria, such as Klebsiella pneumoniae carbapenemase (KPC). Biofilm production is a key factor in KPC colonization and persistence in the host, making the treatment difficult.Gap Statement. The aim of this study was to evaluate the antibiotic resistance, molecular and phenotypic biofilm profiles of 12 KPC isolates associated with nosocomial infection in a hospital in Pelotas, Rio Grande do Sul, Brazil.Methodology. Clinical isolates were obtained from different sources, identified and characterized by antibiotic resistance and carbapenemase synthesis following the Clinical and Laboratory Standards Institute (CLSI) guidelines. Polymerase chain reaction (PCR) was used to evaluate the presence of carbapenemase (blaKPC) and biofilm formation-associated genes (fimA, fimH, rmpA, ecpA, mrkD and wabG). Additionally, phenotypic evaluation of in vitro biofilm formation capacity was evaluated by Congo red agar (CRA) assay and the crystal violet staining method.Results. The 12 isolates evaluated in this study presented the blaKPC gene and were positive for synthesizing carbapenemases in vitro. In the carbapenem class, 83.3 % isolates were resistant and 16.7 % intermediately resistant to imipenem and meropenem. Molecular analyses found that the fimA and wabG genes were detected in 75 % of isolates, while fimH and ecpA were detected in 42 % and mrkD were detected in 8.3 % (1). The CRA assay demonstrated that all isolates were slime producers and 91.7 % (11) of isolates were classified as strong and 8.3 % (1) as moderate biofilm producers by the crystal violet staining method. The optical density (OD_540nm) for strong biofilm formers ranged from 0.80±0.05 to 2.47±0.28 and was 0.55±0.12 for moderate biofilm formers.Conclusion. Our study revealed a high level of antibiotic resistance and biofilm formation in KPC isolates obtained from a hospital in Pelotas, RS, Brazil.

Effectiveness of chlorhexidine in preventing infections among patients undergoing cardiac surgeries: a meta-analysis and systematic review

Background

Although several meta-analyses reported the impact of chlorhexidine (CHX) use in patients undergoing various types of surgery, no meta-analysis summarized the overall effectiveness of CHX specifically for cardiac surgery. This meta-analysis aimed to examine the impact of CHX on infections after cardiac surgery compared with other cleansers or antiseptics.

Methods

PubMed, Embase, and the Cochrane Library were searched from inception up to October 2020 for potentially eligible studies: (1) population: patients who underwent cardiac surgery; (2) intervention or exposure: any type of CHX use in the treatment or exposed group; (3) outcome: number of patients with infections; (4) comparison: placebo or other antiseptic agents; (5) English. The primary outcome was surgical site infection (SSI).

Results

Fourteen studies were included, with 8235 and 6901 patients in the CHX and control groups. CHX was not protective against SSI (OR = 0.77, 95% CI: 0.57–1.04, P = 0.090). CHX was protective for superficial wound infection (OR = 0.42, 95% CI: 0.26–0.70, P = 0.001), but not with deep wound infection (P = 0.509). CHX was not protective against urinary tract of infection (P = 0.415) but was protective for bloodstream infection (OR = 0.36, 95% CI: 0.16–0.80, P = 0.012), nosocomial infections (OR = 0.55, 95% CI: 0.44–0.69, P < 0.001), and pneumonia (OR = 0.26, 95% CI: 0.11–0.61, P = 0.002).

Conclusions

In patients undergoing cardiac surgery, CHX does not protect against SSI, deep wound infection, and urinary tract infections but might protect against superficial SSI, bloodstream infection, nosocomial infections, and pneumonia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-021-01009-3.

Whole-Genome Sequencing Elucidates the Epidemiology of Multidrug-Resistant Acinetobacter baumannii in an Intensive Care Unit

The nosocomial pathogen Acinetobacter baumannii is a frequent cause of healthcare-acquired infections, particularly in critically ill patients, and is of serious concern due to its potential for acquired multidrug resistance. Whole-genome sequencing (WGS) is increasingly used to obtain a high-resolution view of relationships between isolates, which helps in controlling healthcare-acquired infections. Here, we conducted a retrospective study to identify epidemic situations and assess the percentage of transmission in intensive care units (ICUs). Multidrug-resistant A. baumannii (MDR-AB) were continuously isolated from the lower respiratory tract of different patients (at the first isolation in our ICU). We performed WGS, pulsed-field gel electrophoresis (PFGE), and multilocus-sequence typing (MLST) analyses to elucidate bacterial relatedness and to compare the performance of conventional methods with WGS for typing MDR-AB. From June 2017 to August 2018, A. baumannii complex strains were detected in 124 of 796 patients during their ICU stays, 103 of which were MDR-AB. Then we subjected 70 available MDR-AB strains to typing with WGS, PFGE, and MLST. Among the 70 A. baumannii isolates, 38 (54.29%) were isolated at admission, and 32(45.71%) were acquisition isolates. MLST identified 12 unique sequence types, a novel ST (ST2367) was founded. PFGE revealed 16 different pulsotypes. Finally, 38 genotypes and 23 transmissions were identified by WGS. Transmission was the main mode of MDR-AB acquisition in our ICU. Our results demonstrated that WGS was a discriminatory technique for epidemiological healthcare-infection studies. The technique should greatly benefit the identification of epidemic situations and controlling transmission events in the near future.

Is it cost effective to use a 2% chlorhexidine wipes bath to reduce central-line associated blood stream infection? A quasi-experimental study

Background

Bathing with 2% chlorhexidine (CHG) wipes is an important measure regarding infection prevention in critically ill patients. The aim of this study was to evaluate the impact of CHG wipes bath to prevent central-line associated bloodstream infection (CLABSI) in critically ill patients and determine if such measure is cost-saving.

Methods

a quasi-experimental study, conducted from July 2017 to April 2019. Daily bath with 2% CHG was used in all patients at the unit in the intervention period. The following were evaluated: CLABSI incidence density in both periods, 30- day mortality, guided antimicrobials used to treat CLABSI and 2% CHG costs.

Results

CLABSI incidence density dropped from 8.69 to 1.83 per 1.000 central line-days (p = 0.001), mainly by Klebsiella pneumoniae Carbapenen Resistant (Kp-KPC) (p = 0.05). Costs with guided antimicrobials for the treatment in pre-intervention were US$ 46,114.36, and in the intervention period, US$ 4,177.50. The 2% CHG monthly cost was US$ 2,698.00, achieving 30% savings when comparing both periods.

Discussion

An expressive reduction of 79% in CLABSI incidence density was observed, mainly due to Kp-KPC infection and also a reduction in guided antimicrobial costs.

Conclusions

Bathing with 2% CHG led to evident CLABSI reduction.

Chlorhexidine Bathing Strategies for Multidrug-Resistant Organisms: A Summary of Recent Evidence

Objective

The aim of the study was to summarize the latest evidence for patient bathing with a 2% to 4% chlorhexidine gluconate solution to reduce multidrug-resistant organism (MDRO) transmission and infection.

Methods

We searched 3 databases (CINAHL, MEDLINE, and Cochrane) for a combination of the key words “chlorhexidine bathing” and MeSH terms “cross-infection prevention,” “drug resistance, multiple, bacterial,” and “drug resistance, microbial.” Articles from January 1, 2008, to December 31, 2018, were included, as well as any key articles published after December 31.

Results

Our findings focused on health care–associated infections (HAIs) and 3 categories of MDROs: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), and carbapenem-resistant Enterobacteriaceae (CRE). Chlorhexidine bathing reduces MRSA acquisition and carriage, but not all studies found significant reductions in MRSA infections. Several studies found that chlorhexidine bathing reduced VRE acquisition and carriage, and one study showed lower VRE infections in the bathing group. Two studies found that bathing reduced CRE carriage (no studies examined CRE infections). Two very large studies (more than 140,000 total patients) found bathing significantly reduced HAIs, but these reductions may be smaller when HAIs are already well controlled by other means.

Conclusions

There is a high level of evidence supporting chlorhexidine bathing to reduce MDRO acquisition; less evidence is available on reducing infections. Chlorhexidine bathing is low cost to implement, and adverse events are rare and resolve when chlorhexidine use is stopped. There is evidence of chlorhexidine resistance, but not at concentrations in typical use. Further research is needed on chlorhexidine bathing’s impact on outcomes, such as mortality and length of stay.

Cohorting for preventing the nosocomial spread of Carbapenemase-Producing Enterobacterales, in non-epidemic settings: is it mandatory?

BACKGROUND

Worldwide dissemination of Carbapenemase-Producing Enterobacterales (CPE) has led to national and international guidance recommending the implementation of cohorting in healthcare settings (HS). However, in view of recent data regarding the spread of Extended-spectrum Beta-lactamase-producing Enterobacterales, we may wonder about the usefulness of this measure in a non-outbreak settings; here, individual contact isolation may be sufficient to control the risk of dissemination.

AIM/METHODS

We conducted a narrative review of the literature and discussed the role of cohorting.

FINDINGS

CPE are responsible for outbreaks in HS, which are considered the epicentre of spread of resistance strains. CPE are responsible for adverse effects such as increases in hospital stay and costs, less therapeutic options and thus higher risk of clinical failures and mortality. Environment and materials have also been described contaminated with CPE and can be the source of outbreak. Even if guidelines and publications have supported implementation of cohorting, there are no randomized studies demonstrating the mandatory nature of this measure. Most studies are descriptive and cohorting is usually one of several other measures to control outbreaks. Cohorting is not adapted to all HS, which requires human and material resources. Other measures must be strengthened such as compliance of hand hygiene, antibiotic stewardship and surveillance of contact patients. Individual risk factors of acquisition should also be evaluated.

CONCLUSION

Local epidemiology and resources must be assessed before implementing cohorting.

Epidemiology and outcome of Klebsiella pneumoniae carbapenemase-producing Klebsiella pneumoniae (KPC-KP) infections in cardiac surgery patients: a brief narrative review

Klebsiella pneumoniae carbapenemase-producing Klebsiella pneumoniae (KPC-KP) is a difficult-to-treat pathogen due to its multidrug-resistant phenotype. Cardiac surgery patients are at increased risk of developing KPC-KP infections compared to other populations, with previous KPC-KP colonization being a critical factor in influencing the risk of subsequent infection. Two different pieces of information are essential to comprehensively assess the local characteristics of KPC-KP colonization in cardiac surgery patients: (i) the local prevalence of colonization; (ii) the timing of colonization. Treatment of KPC-KP infections in cardiac surgery patients is a complex task, but more effective treatment options have recently become available. Nonetheless, implementation and full adherence to infection-control measures remain of pivotal importance for reducing the burden of KPC-KP infections in this peculiar population. The aim of this narrative review is to summarize the available literature on the epidemiology and outcome of KPC-KP infections in cardiac surgery patients.

Epidemiological profile of healthcare-associated infections caused by Carbapenemase-producing Enterobacteriaceae

OBJECTIVE

To study the epidemiological profile of Healthcare-associated Infections caused by Enterobacteria which carry the Klebsiella pneumoniae Carbapenemase gene (blaKPC) in the hospital environment.

METHOD

A descriptive study was conducted in a private hospital in Belo Horizonte, MG, Brazil, which included all patients with infections caused by Enterobacteriaceae which carry the Klebsiella pneumoniae Carbapenemase gene. The data were collected by the Automated System of Hospital Infection Control and analyzed by descriptive statistics by the Epi Info 7 program.

RESULTS

Eighty-two (82) patients participated in the study. Klebsiella pneumoniae was the most frequent species (68%) isolated in blood (30%), bronchoalveolar lavage (22%) and urine (18%), while catheter-associated bloodstream infection (30%) predominated regarding topography. A case fatality rate of 62% is highlighted in evaluating the outcome.

CONCLUSION

The resistance genes spread rapidly, limiting the antimicrobial options for treating infectious diseases. The epidemiological profile of Healthcare-Associated Infections found in this study can be prevented by prevention and infection control programs.

The impact of chlorhexidine bathing on hospital-acquired bloodstream infections: a systematic review and meta-analysis

Background

Chlorhexidine gluconate (CHG) bathing of hospitalized patients may have benefit in reducing hospital-acquired bloodstream infections (HABSIs). However, the magnitude of effect, implementation fidelity, and patient-centered outcomes are unclear. In this meta-analysis, we examined the effect of CHG bathing on prevention of HABSIs and assessed fidelity to implementation of this behavioral intervention.

Methods

We undertook a meta-analysis by searching Medline, EMBASE, CINAHL, Scopus, and Cochrane’s CENTRAL registry from database inception through January 4, 2019 without language restrictions. We included randomized controlled trials, cluster randomized trials and quasi-experimental studies that evaluated the effect of CHG bathing versus a non-CHG comparator for prevention of HABSIs in any adult healthcare setting. Studies of pediatric patients, of pre-surgical CHG use, or without a non-CHG comparison arm were excluded. Outcomes of this study were HABSIs, patient-centered outcomes, such as patient comfort during the bath, and implementation fidelity assessed through five elements: adherence, exposure or dose, quality of the delivery, participant responsiveness, and program differentiation. Three authors independently extracted data and assessed study quality; a random-effects model was used.

Results

We included 26 studies with 861,546 patient-days and 5259 HABSIs. CHG bathing markedly reduced the risk of HABSIs (IRR = 0.59, 95% confidence interval [CI]: 0.52–0.68). The effect of CHG bathing was consistent within subgroups: randomized (0.67, 95% CI: 0.53–0.85) vs. non-randomized studies (0.54, 95% CI: 0.44–0.65), bundled (0.66, 95% CI: 0.62–0.70) vs. non-bundled interventions (0.51, 95% CI: 0.39–0.68), CHG impregnated wipes (0.63, 95% CI: 0.55–0.73) vs. CHG solution (0.41, 95% CI: 0.26–0.64), and intensive care unit (ICU) (0.58, 95% CI: 0.49–0.68) vs. non-ICU settings (0.56, 95% CI: 0.38–0.83). Only three studies reported all five measures of fidelity, and ten studies did not report any patient-centered outcomes.

Conclusions

Patient bathing with CHG significantly reduced the incidence of HABSIs in both ICU and non-ICU settings. Many studies did not report fidelity to the intervention or patient-centered outcomes. For sustainability and replicability essential for effective implementation, fidelity assessment that goes beyond whether a patient received an intervention or not should be standard practice particularly for complex behavioral interventions such as CHG bathing.

Trial registration

Study registration with PROSPERO CRD42015032523.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4002-7) contains supplementary material, which is available to authorized users.

A Systematic Review and Meta-analyses of the Clinical Epidemiology of Carbapenem-Resistant Enterobacteriaceae

Carbapenem-resistant Enterobacteriaceae (CRE) are major health care-associated pathogens and responsible for hospital outbreaks worldwide. To prevent a further increase in CRE infections and to improve infection prevention strategies, it is important to summarize the current knowledge about CRE infection prevention in hospital settings. This systematic review aimed to identify risk factors for CRE acquisition among hospitalized patients. In addition, we summarized the environmental sources/reservoirs and the most successful infection prevention strategies related to CRE. A total of 3,983 potentially relevant articles were identified and screened. Finally, we included 162 studies in the systematic review, of which 69 studies regarding risk factors for CRE acquisition were included in the random-effects meta-analysis studies. The meta-analyses regarding risk factors for CRE acquisition showed that the use of medical devices generated the highest pooled estimate (odds ratio [OR] = 5.09; 95% confidence interval [CI] = 3.38 to 7.67), followed by carbapenem use (OR = 4.71; 95% CI = 3.54 to 6.26). To control hospital outbreaks, bundled interventions, including the use of barrier/contact precautions for patients colonized or infected with CRE, are needed. In addition, it is necessary to optimize the therapeutic approach, which is an important message to infectious disease specialists, who need to be actively involved in a timely manner in the treatment of patients with known CRE infections or suspected carriers of CRE.