Antibiotic use and the risk of carbapenem-resistant extended-spectrum-{beta}-lactamase-producing Klebsiella pneumoniae infection in hospitalized patients: results of a double case-control study

The Global and Regional Prevalence of Hospital-Acquired Carbapenem-Resistant Klebsiella pneumoniae Infection: A Systematic Review and Meta-analysis

Background

Due to scarce therapeutic options, hospital-acquired infections caused by Klebsiella pneumoniae (KP), particularly carbapenem-resistant KP (CRKP), pose enormous threat to patients' health worldwide. This study aimed to characterize the epidemiology and risk factors of CRKP among nosocomial KP infections.

Method

MEDLINE, Embase, PubMed, and Google Scholar were searched for studies reporting CRKP prevalence from inception to 30 March 2023. Data from eligible publications were extracted and subjected to meta-analysis to obtain global, regional, and country-specific estimates. To determine the cause of heterogeneity among the selected studies, prespecified subgroup analyses and meta-regression were also performed. Odds ratios of CRKP-associated risk factors were pooled by a DerSimonian and Laird random-effects method.

Results

We retained 61 articles across 14 countries and territories. The global prevalence of CRKP among patients with KP infections was 28.69% (95% CI, 26.53%-30.86%). South Asia had the highest CRKP prevalence at 66.04% (95% CI, 54.22%-77.85%), while high-income North America had the lowest prevalence at 14.29% (95% CI, 6.50%-22.0%). In the country/territory level, Greece had the highest prevalence at 70.61% (95% CI, 56.77%-84.45%), followed by India at 67.62% (95% CI, 53.74%-81.79%) and Taiwan at 67.54% (95% CI, 58.65%-76.14%). Hospital-acquired CRKP infections were associated with the following factors: hematologic malignancies, corticosteroid therapies, intensive care unit stays, mechanical ventilations, central venous catheter implantations, previous hospitalization, and antibiotic-related exposures (antifungals, carbapenems, quinolones, and cephalosporins).

Conclusions

Study findings highlight the importance of routine surveillance to control carbapenem resistance and suggest that patients with nosocomial KP infection have a very high prevalence of CRKP.

Perinatal colonization with extended-spectrum beta-lactamase-producing and carbapenem-resistant Gram-negative bacteria: a hospital-based cohort study

BACKGROUND

Antimicrobial resistance (AMR) is a growing global health threat that contributes to substantial neonatal mortality. Bangladesh has reported some of the highest rates of AMR among bacteria causing neonatal sepsis. As AMR colonization among newborns can predispose to infection with these bacteria, we aimed to characterize the frequency of and risk factors for colonization of mothers and newborns during hospitalization for delivery.

METHODS

We enrolled pregnant women presenting for delivery to a tertiary care hospital in Faridpur, Bangladesh. We collected vaginal and rectal swabs from mothers pre- and post-delivery, rectal swabs from newborns, and swabs from the hospital environment. Swabs were plated on agars selective for extended-spectrum-beta-lactamase producing bacteria (ESBL-PB) and carbapenem-resistant bacteria (CRB). We performed logistic regression to determine factors associated with ESBL-PB/CRB colonization.

RESULTS

We enrolled 177 women and their newborns during February-October 2020. Prior to delivery, 77% of mothers were colonized with ESBL-PB and 15% with CRB. 79% of women underwent cesarean deliveries (C-section). 98% of women received antibiotics. Following delivery, 98% of mothers and 89% of newborns were colonized with ESBL-PB and 89% of mothers and 72% of newborns with CRB. Of 290 environmental samples, 77% were positive for ESBL-PB and 69% for CRB. Maternal pre-delivery colonization was associated with hospitalization during pregnancy (RR for ESBL-PB 1.24, 95% CI 1.10-1.40; CRB 2.46, 95% CI 1.39-4.37). Maternal post-delivery and newborn colonization were associated with C-section (RR for maternal CRB 1.31, 95% CI 1.08-1.59; newborn ESBL-PB 1.34, 95% CI 1.09-1.64; newborn CRB 1.73, 95% CI 1.20-2.47).

CONCLUSIONS

In this study, we observed high rates of colonization with ESBL-PB/CRB among mothers and newborns, with pre-delivery colonization linked to prior healthcare exposure. Our results demonstrate this trend may be driven by intense use of antibiotics, frequent C-sections, and a contaminated hospital environment. These findings highlight that greater attention should be given to the use of perinatal antibiotics, improved surgical stewardship for C-sections, and infection prevention practices in healthcare settings to reduce the high prevalence of colonization with AMR organisms.

Risk factors and molecular epidemiology of bloodstream infections due to carbapenem-resistant Klebsiella pneumoniae

PURPOSE

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is emerging as a worldwide public health concern; however, molecular epidemiological surveillance of clinical CRKP bloodstream infection (BSI) in China is limited. We conducted a retrospective observational study to assess risk factors and the molecular epidemiology of CRKP BSI.

METHODS

We reviewed the medical records of enrolled patients to assess risk factors of CRKP BSI. Characteristics of CRKP isolates were analyzed by whole genome sequencing and Kleborate. Evolutionary diversification in CRKP isolates was described through Single Nucleotide Polymorphisms analysis and phylogenetic tree construction.

RESULTS

We found that prior ICU hospitalization and use of carbapenems were independent risk factors for CRKP BSI. The main CRKP sequence type (ST) and capsular serotype were ST11 and KL64, and KPC-2 was the most prevalent enzyme type of carbapenemase-carrying Klebsiella pneumoniae. The most prevalent aerobactin and yersiniabactin of ST11-CRKP were iuc-1 and ybt9 ICEKp3, as for KL64-CRKP. Phylogenomic analysis showed that the antibacterial resistance genes on plasmids were highly consistent, but the genetic background of the chromosomes was still different.

CONCLUSIONS

Our findings are important for hospitals, allowing them to limit dissemination of CRKP and optimize antibiotic administration.

Characterization of KPC-2-producing Klebsiella pneumoniae and affected patients of a pediatric hospital in Brazil

Carbapenemase-producing Klebsiella pneumoniae (CPKp) infections are important threats to pediatric populations. Thus, a retrospective study was conducted in a Brazilian reference pediatric hospital, and 26 CPKp isolates obtained from 23 patients were characterized. The affected population had important underlying diseases, reflecting previous hospitalization and antibiotic use. Most CPKp isolates were resistant to all antibiotic classes, and bla_KPC-2 was the only carbapenemase-encoding gene. bla_CTX-M-15 was common among the isolates, and modification or absence of the mgrB gene was the cause of polymyxin B resistance. Ten different sequence types were identified, and clonal complex 258 was prevalent. Alleles wzi50 and wzi64 were the most recurrent ones regarding K-locus type, with a remarkable contribution of the epidemic ST11/KL64 lineage as a colonizer. Our findings show that lineages associated with the pediatric population are similar to those found in adults, reinforcing the need for epidemiological surveillance to effectively implement prevention and control measures.

Analysis of risk factors associated with healthcare-associated carbapenem-resistant Klebsiella pneumoniae infection in a large general hospital: a case-case-control study

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection is a major public health threat in the world. To inform the prevention and control of CRKP infection in hospitals, this study analyzed the factors associated with CRKP infection and resistance to carbapenems in K. pneumoniae. This case-case-control study was carried out in a large general hospital in China from January 2016 to December 2018, comprising 494 hospitalized patients infected with CRKP (case group 1) and 2429 hospitalized patients infected with carbapenem-susceptible K. pneumoniae (CSKP, case group 2). We selected control groups from hospitalized patients without K. pneumoniae infections for the two case groups separately, with a 1:3 case-control ratio, to analyze the risk factors of the two case groups using the conditional logistic regression. Multivariate analysis showed that the risk factors of CRKP infection were intensive care unit (ICU) admission (odds ratio [OR], 6.85; 95% confidence interval [CI], 4.90-9.58; P < 0.001), respiratory failure (OR, 1.93; 95% CI, 1.34-2.77; P < 0.001), age-adjusted Charlson comorbidity index (aCCI; OR, 1.08; 95% CI, 1.02-1.15; P = 0.007), admission from the Emergency (OR, 1.37; 95% CI, 1.02-1.85; P = 0.036), and imipenem use (OR, 1.80; 95% CI, 1.30-2.49; P < 0.001). Among the aforementioned five risk factors, aCCI (OR, 1.09; 95% CI, 1.06-1.13; P < 0.001) was also identified as a risk factor of CSKP infections in multivariate analysis. The risk factors for resistance to carbapenems in K. pneumoniae were ICU admission, respiratory failure, admission from the Emergency, and imipenem use.

Epidemiological and Antimicrobial Resistant Patterns, and Molecular Mechanisms of Carbapenem-Resistant Klebsiella pneumoniae Infections in ICU Patients

Objective

To study the epidemiological and antimicrobial resistant patterns, clinical characteristics and risk factors of critically ill patients infected with carbapenem-resistant Klebsiella pneumoniae (CRKP) from intensive care units (ICUs). The potential molecular mechanisms of antimicrobial resistance and virulence of CRKP were investigated through evaluation of associated genes.

Methods

Totally, 201 ICU patients infected with K. pneumoniae were recruited from January 2020 through January 2021. K. pneumoniae strains were collected from diverse clinical specimens and identified by microbial cultures and matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. Antimicrobial resistance was measured through broth micro-dilution or Kirby-Bauer assays. The carbapenemase-, virulence-, and capsular serotype-associated genes of CRKP were individually detected by PCR and sequencing. Demographic and clinical profiles were acquired from hospital databases to evaluate the correlation of CRKP infection incidence with clinical risk factors.

Results

Of the 201 K. pneumoniae strains, CRKP accounted for 41.29%. Seasonal bias existed in local prevalence of CRKP infections. CRKP strains mounted significantly strong resistance against major antimicrobial agents except ceftazidime-avibactam, tigecycline and minocycline. Recent exposure to certain antibiotics and prior treatment with invasive interventions were prone to increase CRKP infection risks with worsened infectious outcomes. The local top carbapenemase-encoding and virulence-associated genes of CRKP were bla_KPC and irp2, respectively. Nearly half of CRKP isolates harbored a capsular polysaccharide serotype of K14.K64 (wzi-64) which preferentially emerged in the cohort with worse outcomes of infection.

Conclusion

Featured epidemiology and typical clinical characteristics existed extensively in K. pneumoniae infections among ICU patients. The CRKP cohort exhibited substantially high antimicrobial resistance. Distinctive carbapenemase-, virulence-, and serotype-associated genes were intensively involved in the spread and pathogenesis of CRKP. These findings supported careful management of critically ill patients potentially infected with virulent CRKP in the ICUs.

Effect of restricting piperacillin/tazobactam prescription on rates of antimicrobial resistance in gram-negative bacteria and antibiotic consumption

The increasing resistance of gram-negative bacteria is a serious global public health concern. One way to prevent increasing antibiotic resistance is by implementing the antibiotic stewardship program. This study aimed to assess the changes in the consumption of antimicrobials and antimicrobial resistance rates after implementing piperacillin/tazobactam restriction. This study was conducted at Kandong Sacred Heart Hospital. We retrospectively collected and analysed data between October 2018 and May 2021 to evaluate antibiotic consumption and resistance patterns after restricting piperacillin/tazobactam. This study included two periods, a 16-month pre-restriction period and a 16-month post-restriction period. During the study period, there was a significant decrease in the consumption of piperacillin/tazobactam after implementing the restriction policy (127.82 ± 9.39 to 104.82 ± 15.66 defined daily doses/1000 patient days, p < 0.001). A significant decrease in the resistance rate of Acinetobacter spp. was observed for cefepime (p = 0.001), ceftazidime (p = 0.004), levofloxacin (p = 0.021), meropenem (p = 0.002) and piperacillin (p = 0.028). The introduction of piperacillin/tazobactam restriction reduced their use and positively impacted the resistance rates of Acinetobacter spp., carbapenem-resistant Pseudomonas spp. and carbapenem-resistant Enterobacteriaceae which are major threats to nosocomial infections.

Diversity of Circulating NKT Cells in Defense against Carbapenem-Resistant Klebsiella Pneumoniae Infection

Nosocomial infection caused by carbapenem-resistant Klebsiella pneumonia (CRKP) infection has become a global public health problem. Human NK and NKT cells in peripheral immune responses are recognized as occupying a critical role in anti-bacterial immunity. Through performed scRNA-seq on serial peripheral blood samples from 3 patients with CRKP undergoing colonization, infection, and recovery conditions, we were able to described the immune responses of NK and NKT cells during CRKP infection and identified a mechanism that could contribute to CRKP clearance. The central player of CRKP infection process appears to be the NKT subset and CD56hiNKT subset which maintained immune competence during CRKP colonization. With time, CRKP leads to the loss of NK and CD160hiNKT cells in peripheral blood, resulting in suppressed immune responses and increased susceptibility to opportunistic infection. In summary, our study identified a possible mechanism for the CRKP invasion and to decipher the clues behind the host immune response that influences CRKP infection pathogenesis.

Prevalence and incidence of carbapenem-resistant K. pneumoniae colonization: systematic review and meta-analysis

BACKGROUND

Klebsiella pneumoniae is a gram-negative rod belonging to the order Enterobacterales and having a wide distribution in the environment, including the human colon. Recently, the bacterium is one of the known problems in the healthcare setting as it has become resistant to last-resort drugs like carbapenems. The colonized person can serve as a reservoir for his/herself and others, especially in the healthcare setting leading to nosocomial and opportunistic infections. Therefore, we aimed to quantitatively estimate the rate of prevalence and incidence of colonization with carbapenem-resistant K. pneumoniae.

METHODS

A literature search was conducted on PubMed/MEDLINE, Google Scholar, Science Direct, Cochrane Library, WHO Index Medicus, and university databases. The study includes all published and unpublished papers that addressed the prevalence or incidence of K. pneumoniae colonization. Data were extracted onto format in Microsoft Excel and pooled estimates with a 95% confidence interval calculated using Der-Simonian-Laird random-effects model. With the use of I² statistics and prediction intervals, the level of heterogeneity was displayed. Egger's tests and funnel plots of standard error were used to demonstrate the publication bias.

RESULTS

A total of 35 studies were included in the review and 32 records with 37,661 patients for assessment of prevalence, while ten studies with 3643 patients for incidence of colonization. The prevalence of carbapenem-resistant K. pneumoniae colonization varies by location and ranges from 0.13 to 22%, with a pooled prevalence of 5.43%. (3.73-7.42). Whereas the incidence of colonization ranges from 2 to 73% with a pooled incidence of 22.3% (CI 12.74-31.87), both prevalence and incidence reports are majorly from developed countries. There was a variation in the distribution of carbapenem resistance genes among colonizing isolates with KPC as a prominent gene reported from many studies and NDM being reported mainly by studies from Asian countries. A univariate meta-regression analysis indicated continent, patient type, study design, and admission ward do not affect the heterogeneity (p value>0.05).

CONCLUSION

The review revealed that colonization with K. pneumoniae is higher in a healthcare setting with variable distribution in different localities, and resistance genes for carbapenem drugs also have unstable distribution in different geographic areas.

Risk factors and clinical outcomes of carbapenem-resistant Klebsiella pneumonia infection in intensive care unit: A retrospective observational study in a tertiary care hospital in Eastern India

Background

Carbapenem-resistant Enterobacteriaceae, especially Klebsiella pneumonia, have become a severe global problem with a significant threat to public health, but few studies have investigated the risk factors and epidemiology of carbapenem-resistant K. pneumonia (CRKP) infections in India.

Methods

We performed a retrospective observational study of 224 participants with K. pneumoniae who were admitted to the medical intensive care unit (ICU) of Institute of Medical Sciences and SUM Hospital, Bhubaneswar, India, between January 1 and December 30, 2020. Antibiotic susceptibility testing was done by automated broth microdilution VITEK® 2 (BioMerieux, Inc., Hazelwood, USA). The Clinical and Laboratory Standards Institute document M100-S22 (January 2020) was used to interpret antimicrobial susceptibility testing. Data were obtained from paper medical records.

Results

Two hundred and twenty-four subjects with culture-positive for K. pneumonia were retrieved during the study period, out of which 108 had CRKP. The risk factors for univariate analysis were Acute Physiology and Chronic Health Evaluation II, ICU length of stay (LOS), invasive mechanical ventilator days, central venous catheter days, and arterial line days. The multivariate analysis showed invasive mechanical ventilation and ICU LOS were independent risk factors for CRKP infection. Mortality in the CRKP group was 48 (44%) compared to 27 (23%) in the carbapenem-sensitive K. pneumonia (CSKP) group, which was statistically significant (P < 0.01).

Conclusion

Infection due to CRKP in the ICU was associated with 1.9 times higher mortality as compared to CSKP. Invasive mechanical ventilation and ICU LOS were found to be independent risk factors for CRKP infection.

Case-case-control study of risk factors for carbapenem-resistant Enterobacterales infections among hospitalized patients

OBJECTIVE

To identify important risk factors for carbapenem-resistant Enterobacterales (CRE) infections among hospitalized patients.

DESIGN

We utilized a case-case-control design that compared patients with CRE infections to patients with carbapenem-susceptible Enterobacterales (CSE) infections and randomly selected controls during the period from January 2011 through December 2016.

SETTING

The study population was selected from patients at a large metropolitan tertiary-care and instructional medical center.

PATIENTS

Cases of CRE were defined as initial admission of adults diagnosed with a bacterial infection of an Enterobacterales species resistant clinically or through sensitivity testing to carbapenems 48 hours or more after admission. Cases of CSE were selected from the same patient population as the CRE cases within a 30-day window for admission, with diagnostic pathogens identified as susceptible to carbapenems. Controls were defined as adult patients admitted to any service within a 30-day window from a CRE case for >48 hours who did not meet either of the above case definitions during that admission.

RESULTS

Antibiotic exposure within 90 days prior to admission and length of hospital stay were both associated with increased odds of CRE and CSE infections compared to controls. Patients with CRE infections had >18 times greater odds of prior antibiotic exposure compared to patients with CSE infections.

CONCLUSIONS

Antibiotic exposure and increased length of hospital stay may result in increased patient risk of developing an infection resistant to carbapenems and other β-lactams.

Different Effects of Antibiotics on Klebsiella pneumoniae and Escherichia coli Resistance Induced by Antibiotics: A Retrospective Study from China

Objective: The main objective was to assess the correlation between antibiotic use and carbapenem-resistant Klebsiella pneumoniae (CRKP) and carbapenem-resistant Escherichia coli (CREC) induction by antibiotics. Materials and Methods: A retrospective cohort study was conducted from January 2017 to December 2020. This study included patients with K. pneumoniae and E. coli. Kaplan-Meier analysis and Cox proportional hazard model were used to estimate the hazard of carbapenem-resistant Enterobacterales (CRE), whereas restricted cubic spline regression was used to visualize the hazard of CRE by antibiotics at different doses. Results: Two thousand fifty-six K. pneumoniae patients and 3,243 E. coli patients were included. After Cox proportional hazard model analysis, carbapenems or 1st-cephalospoins or penicillin monotherapy, male and ICU admission were associated with CRKP. CREC was associated with quinolone monotherapy. Time-to-event analysis indicated that carbapenem, β-lactamase inhibitor mixtures, and quinolones were associated with higher 30-day CRKP hazards than other antibiotics (χ² = 33.670, p < 0.001). Further restricted cubic spline regression analysis found that the hazard of CRKP induction decreased with the increased dose of β-lactamase inhibitor mixtures, but there was no significant change in the hazard ratio of CRKP induction with the increased dose of quinolones. Moreover, there was an obvious characteristic of "parabolic curve" for the hazard of CREC induction due to β-lactamase inhibitor mixtures, and the hazard value gradually increased with the dose, reached the maximum at 24 g, and finally gradually decreased from 26 g. Conclusions: Rational use of antibiotics should be implemented and antimicrobial stewardship policies should be adjusted according to the characteristics of each hospital.

Risk factors for infection and mortality caused by carbapenem-resistant Klebsiella pneumoniae: a large multicentre case-control and cohort study

OBJECTIVES

To elucidate the predictors of carbapenem-resistant Klebsiella pneumoniae (CRKP) infection and help clinicians better identify CRKP infection at an early age.

METHODS

We conducted a multicentre case-control study of 422 patients with CRKP infection and 948 with carbapenem-susceptible K. pneumoniae (CSKP) infection from March to July 2017. Binary logistic regression was used to identify risk factors for CRKP infection. The subgroups of CRKP respiratory infection, intra-abdominal infection, and bloodstream infection were also evaluated. Patients were followed up for 28 days. Independent risk factors for 28-day crude mortality of CRKP infection were analysed using Cox proportional hazards regression models.

RESULTS

Longer stay of hospitalization, stay in the ICU, previous exposure to antibacterial agents (especially carbapenems, quinolones, aminoglycosides, and tigecycline), invasive procedures, intravascular catheter use, tracheotomy, or admission to ICU in the preceding 90 days were risk factors for CRKP infection. Carbapenem exposure was the only common predictor of different types of CRKP infection. The 28-day mortality of CRKP infection was 13.1% and was independently associated with sex, admitted unit, and types of infection.

CONCLUSIONS

Strict policies for antibiotic use, cautious decisions regarding the implementation of invasive procedures, and careful management of patients with catheters, especially intravascular catheters, are necessary to handle CRKP infection.

The Value of Neutrophil-To-Lymphocyte Ratio for Evaluating Blood Stream Infection Caused by Carbapenem-Resistant Klebsiella pneumoniae: A Retrospective Cohort Study

Background

The neutrophil-to-lymphocyte ratio (NLR) is a useful marker of inflammation. However, the prognostic function of the NLR in patients with carbapenem-resistant Klebsiella pneumoniae (CRKP) blood stream infection (BSI) remains largely unknown. The aim of this study was to explore the potential relationship between the NLR and mortality in these patients.

Methods

We performed a retrospective cohort study based on data retrieved from the computerized patient record system in a tertiary hospital from 1 January 2017 to 31 October, 2020. A total of 134 inpatients with CRKP BSI were enrolled in this study, including 54 fatal cases and 80 survival cases, 28 days after the onset of CRKP BSI. A logistic analysis was performed to assess the association between the NLR on the 4th day and 28-day mortality. Multivariate analyses were used to control for the confounders.

Results

The overall 28-day mortality rate of patients with a CRKP BSI episode was 40.3% (54/134). We conducted a multivariate analysis of the data of 134 patients and found that the NLR on the 4th day [odds ratio (OR) 1.148, 95% confidence interval (CI) 1.076–1.225, p < 0.001] and antibiotic exposure before BSI onset (OR 3.847, 95% CI 1.322–11.196, p = 0.013) were independent risk factors for 28-day mortality of patients with CRKP BSI, while appropriate initial therapy (AIT, OR 0.073, 95% CI 0.017–0.307, p < 0.001) was an independent protective factor. Among patients treated with AITs, the Cox proportional hazards regression analysis revealed a significant difference in prognosis (p = 0.006) between the ceftazidime/avibactam contained (CAZ) group and non CAZ-AVI groups. After dividing the non CAZ-AVI group into the tigecycline (TGC), colistin (COL), and TGC + COL groups, there were no differences between the CAZ-AVI group and the TGC group (p = 0.093), but CAZ-AVI group showed lower 28-day mortality than COL (p = 0.002) and TGC + COL (p = 0.002) groups. Meanwhile, there was no difference in NLR on the 1st day (p = 0.958) of patients in different groups but significant difference in NLR on the 4th day (p = 0.047).

Conclusions

The NLR on the 4th day is a readily available and independent prognostic biomarker for patients with CRKP BSI. This marker may have the potential for use in evaluating the efficacy of different anti-infection therapy strategies at an early stage.

Risk factors for and clinical outcomes of ceftazidime-avibactam-resistant carbapenem-resistant Klebsiella pneumoniae nosocomial infections: a single-center retrospective study

PURPOSE

The emergence of ceftazidime-avibactam (CZA) resistance in carbapenem-resistant Klebsiella pneumoniae (CRKP) has been increasingly reported in recent years. We aimed to identify the risk factors of CZA-resistant CRKP infection and assess clinical outcomes of the patients.

METHODS

The study retrospectively analyzed the clinical and microbiological data of patients with CRKP infection to identify risk factors, clinical features, and outcomes using multivariate logistic regression analysis.

RESULTS

A total of 103 patients with CRKP infection were enrolled in this study. Multivariate analysis showed previous renal replacement therapy (OR 3.966, 95% CI 1.301-12.090, P = 0.015) was an independent risk factor for CZA-resistant CRKP infection. The 28-day mortality was higher in patients infected with CZA-resistant CRKP (27.9%) than those with CZA-susceptible CRKP (7.1%) (P = 0.009). CZA-resistant CRKP infection (OR 20.308, 95% CI 1.461-282.293, P = 0.025), and mechanical ventilation (OR 14.950, 95% CI 1.034-216.212, P = 0.047) were independent predictors for 28-day mortality in patients with CRKP infection. Lower level of platelet count (OR 0.987, 95% CI 0.975-0.999, P = 0.032) on the day of CRKP infection onset was related to 28-day mortality. Kaplan-Meier curves showed that the CZA-resistant CRKP group had a shorter survival time than the CZA-susceptible CRKP group.

CONCLUSION

The prevalence and mortality of CZA-resistant CRKP are still increasing. Strengthening the hospital infection control of renal replacement therapy and mechanical ventilation may help to prevent CZA-resistant CRKP.

Prevalence and molecular characterization of antibiotic resistance and associated genes in Klebsiella pneumoniae isolates: A clinical observational study in different hospitals in Chattogram, Bangladesh

Objective

This study was performed to investigate the prevalence of multidrug resistance and molecular characterization of Klebsiella pneumoniae (KPN) from clinical isolates in the southern region of Bangladesh. Additional analysis of the prevalence of bla_NDM-1, bla_SHV-11, uge genes of KPN was also carried out among these clinical isolates.

Method

The study was carried out using 1000 clinical isolates collected from two different hospitals of Chattogram. A drug susceptibility test was performed by the disk diffusion method to detect KPN’s response to 16 antibiotics. The presence of antibiotic-resistant and (or) virulent genes bla_NDM-1, bla_SHV-11, uge were investigated using the PCR technique. Isolates having bla_NDM-1, bla_SHV-11, uge gene were further validated by sequencing followed by phylogenetic analysis. Phylogenetic relationships among these isolates were determined by Clustal omega and MEGA7.

Result

A total of 79%, 77%, 74.9%, 71%, 66% and 65% isolates exhibited resistance against cefuroxime, cefixime, cefotaxime, ceftazidime, cefepime and ceftriaxone respectively. The frequency of resistance to other antibiotics varied from 26.5% to 61.8%. PCR analysis showed that 64% of strains harbored bla_NDM-1 gene, and 38% strains harbored bla_SHV-11 gene. Moreover, 47% of samples were carrying uge gene, and 19% of samples carried bla_NDM-1, bla_SHV-11, uge genes together.

Conclusion

In this study, we’ve analysed the pattern of expression as well as prevalence of bla_NDM-1, bla_SHV-11, and uge genes in Klebsiella isolates. Upon molecular and statistical analysis, we found a high prevalence of multi-drug resistance KPN strains in the isolates. The Klebsiella isolates were confirmed to harbor multiple ESBL genes and 64% of the isolates were found to be producing NDM-1. As multidrug resistance is an alarming issue, continuous surveillance and routine clinical detection of resistant bacteria and plasmids are necessary to prevent catastrophic public health incidents.

Do specific antimicrobial stewardship interventions have an impact on carbapenem resistance in Gram-negative bacilli? A multicentre quasi-experimental ecological study: time-trend analysis and characterization of carbapenemases

BACKGROUND

Carbapenem-resistant Gram-negative bacilli (CR-GNB) are among the most threatening microorganisms worldwide and carbapenem use facilitates their spread. Antimicrobial stewardship programmes (ASPs) can help to optimize the use of antibiotics. This study evaluates the impact of a multifaceted educational ASP on carbapenem use and on the epidemiology of CR-GNB.

METHODS

We conducted a quasi-experimental, time-series study in seven hospitals, from January 2014 to September 2018. The key intervention was composed of educational interviews promoting the appropriate use of carbapenems. The primary endpoints were carbapenem consumption and incidence density (ID) of CR-GNB. All non-duplicated CR-GNB clinical isolates were tested using phenotypic assays and PCR for the presence of carbapenemases. Joinpoint regression and interrupted time-series analyses were used to determine trends.

RESULTS

A decrease in carbapenem consumption throughout the study period [average quarterly percentage change (AQPC) -1.5%, P < 0.001] and a -8.170 (-16.064 to -0.277) level change following the intervention were observed. The ID of CR-Acinetobacter baumannii decreased (AQPC -3.5%, P = 0.02) and the overall ID of CR-GNB remained stable (AQPC -0.4%, P = 0.52). CR-GNB, CR-Pseudomonas aeruginosa and CR-A. baumannii IDs per hospital correlated with the local consumption of carbapenems. The most prevalent carbapenem resistance mechanisms were OXA-23 for CR-A. baumannii (76.1%), OXA-48 for CR-Klebsiella pneumoniae (66%) and no carbapenemases for CR-P. aeruginosa (91.7%). The epidemiology of carbapenemases was heterogeneous throughout the study, especially for carbapenemase-producing Enterobacteriaceae.

CONCLUSIONS

In conclusion, a multifaceted, educational interview-based ASP targeting carbapenem prescribing reduced carbapenem use and the ID of CR-A. baumannii.

Prior Antibiotic Therapy and the Onset of Healthcare-Associated Infections Sustained by Multidrug-Resistant Klebsiella pneumoniae in Intensive Care Unit Patients: A Nested Case-Control Study

Epidemiological research has demonstrated direct relationships between antibiotic consumption and the emergence of multidrug-resistant (MDR) bacteria. In this nested case-control study, we assessed whether prior exposure to antibiotic therapy and its duration affect the onset of healthcare-associated infections (HAIs) sustained by MDR Klebsiella pneumoniae (MDR-Kp) in intensive care unit patients. Cases were defined as patients who developed an MDR-Kp HAI. Controls matched on sex and the length of intensive care unit (ICU) stay were randomly selected from the at-risk population. Any antibiotic agent received in systemic administration before the onset of infection was considered as antibiotic exposure. Multivariable conditional logistic regression analyses were performed to estimate the effect of prior exposure to each antibiotic class (Model 1) or its duration (Model 2) on the onset of HAIs sustained by MDR-Kp. Overall, 87 cases and 261 gender-matched controls were compared. In Model 1, aminoglycosides and linezolid independently increased the likelihood of developing an MDR-Kp HAI, whereas exposure to both linezolid and penicillins reduced the effect of linezolid alone. In Model 2, cumulative exposure to aminoglycosides increased the likelihood of the outcome, as well as cumulative exposures to penicillins and colistin, while a previous exposure to both penicillins and colistin reduced the influence of the two antibiotic classes alone. Our study confirms that aminoglycosides, penicillins, linezolid, and colistin may play a role in favoring the infections sustained by MDR-Kp. However, several double exposures in the time window before HAI onset seemed to hinder the selective pressure exerted by individual agents.

A Retrospective Analysis of Risk Factors and Outcomes of Carbapenem-Resistant Klebsiella pneumoniae Bacteremia in Nontransplant Patients

BACKGROUND

Carbapenem-resistant Klebsiella pneumoniae (CRKP) has become a major problem among nosocomial infections, and it is a serious threat to patients. The clinical characteristics and outcome of CRKP bloodstream infection (BSI) in nontransplant patients remains unelucidated. The aim of this study was as follows: identify the risk factors of CRKP infection; generate new ideas for prevention; and generate new ideas for the most effective therapeutic management in nontransplant patients.

METHODS

The study retrospectively analyzed the clinical and microbiological data of nontransplant patients with K pneumoniae (KP) bacteremia from January 2013 to December 2015 to identify risk factors, clinical features, and outcomes using multivariate logistic regression analysis.

RESULTS

Of the 371 patients with KP-BSI in nontransplant patients included in this study, 28.0% (N = 104) had CRKP. The 28-day mortality was higher in patients infected with CRKP (55.8%) than in those with carbapenem-susceptible KP (13.9%) (P < .001). Multivariate analysis showed previous gastric catheterization, previous use of carbapenems, hypoproteinemia, and high Acute Physiologic Assessment and Chronic Health Evaluation II scores as independent risk factors for CRKP-BSIs. Carbapenem-resistant KP infection, severe illness, and tigecycline therapy were independent risk factors for death from KP-BSIs. Taken together, inappropriate antibiotic treatment both in empirical and definitive therapy and imipenem minimum inhibitory concentrations (MICs) of >8 mg/L were associated with poor clinical outcome.

CONCLUSIONS

Nontransplant patients with CRKP-BSI had higher mortality. Carbapenems exposure was an independent risk factor for CRKP infection. Imipenem MICs of >8 mg/L, tigecycline therapy, and inappropriate treatments increased the 28-day mortality of KP-BSI patients.

The Continuing Plague of Extended-Spectrum β-Lactamase Producing Enterbacterales Infections: An Update

Antimicrobial resistance is a common iatrogenic complication of modern life and medical care. One of the most demonstrative examples is the exponential increase in the incidence of extended-spectrum β-lactamases (ESBLs) production among Enterobacteriaceae, that is, the most common human pathogens outside of the hospital setting. Infections resulting from ESBL-producing bacteria are associated with devastating outcomes, now affecting even previously healthy individuals. This poses an enormous burden and threat to public health. This article aims to narrate the evolving epidemiology of ESBL infections and highlights current challenges in terms of management and prevention of these common infections.

Bacteremia Caused by Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae in Vientiane, Lao PDR: A 5-Year Study

Although there has been an increasing incidence of bacteremia caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae (ESBL-E) across South East Asia, there are sparse data from the Lao PDR, where laboratory capacity for antimicrobial resistance surveillance is limited. We, therefore, retrospectively reviewed bacteremia caused by ESBL-producing Escherichia coli and Klebsiella pneumoniae between 2010 and 2014 at Mahosot Hospital, Vientiane, Lao PDR. Clinical and laboratory data relating to all episodes of ESBL-E bacteremia were reviewed over the 5-year period and compared with non-ESBL-E bacteremia. Blood cultures positive for E. coli or K. pneumoniae were identified retrospectively from laboratory records. Clinical and laboratory data were extracted from research databases and case notes and analyzed using STATA. Between 2010 and 2014, we identified 360 patients with E. coli (n = 249) or K. pneumoniae (n = 111) bacteremia, representing 34.8% of all patients with clinically significant bacteremia. Seventy-two (20%) isolates produced ESBL; E. coli accounted for 15.3% (55/360) and K. pneumoniae for 4.7% (17/360), respectively. The incidence of ESBL-producing E. coli bacteremia rose during the study period. By multiple logistic analysis, reported antibiotic use in the previous week was significantly associated with ESBL positivity (P < 0.001, odds ratio 3.89). Although multiresistant, most ESBL-producing E. coli and K. pneumoniae remained susceptible to meropenem (65/65; 100%) and amikacin (64/65; 98.5%). We demonstrated an alarming increase in the incidence of ESBL-E as a cause of bacteremia in Vientiane during the study period. This has implications for empiric therapy of sepsis in Laos, and ongoing surveillance is essential.

Tigecycline Therapy for Infections Caused by Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae in Critically Ill Patients

: We aimed to evaluate tigecycline on the clinical effectiveness in treating complicated skin and soft tissue infections (cSSTI), complicated intra-abdominal infections (cIAI), and pneumonia, caused by extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, as data are limited. From three medical centers in Taiwan, we retrospectively studied the cSSTI, cIAI, and/or pneumonia caused by ESBL-producing Enterobacteriaceae. Among the 71 patients, including 39 patients infected with Klebsiella pneumoniae, 30 infected with Escherichia coli and others, the clinical success rate of tigecycline-based therapy was 80%-90% for pneumonia and cSSTI caused by E. coli and 50%-60% for cIAI caused by K. pneumoniae and E. coli. Microbiological and clinical outcome of pneumonia caused by carbapenem-resistant K. pneumoniae was poor. Univariate Cox analysis showed that dyspnea, SOFA score, septic shock, thrombocytopenia, prolonged prothrombin time, and lesser microbiological eradication were significant factors associated with 30-day mortality after the end of therapy. Cox regression proportional hazards model revealed dyspnea and a SOFA score > 8 to be independently associated with time to death. For ESBL producers, tigecycline showed good effects for cSSTI and pneumonia by E. coli, ordinary for cIAI, but ineffective for pneumonia by K. pneumoniae. Dyspnea and a high SOFA score predict a poor outcome.

Klebsiella pneumoniae: an increasing threat to public health

OBJECTIVES

This review fills the paucity of information on K. pneumoniae as a nosocomial pathogen by providing pooled data on epidemiological risk factors, resistant trends and profiles and resistant and virulent genes of this organism in Asia.

METHODS

Exhaustive search was conducted using PubMed, Web of Science, and Google scholar for most studies addressing the prevalence, risk factors, drug resistant-mediated genes and/or virulent factors of K. pneumoniae in Asia. Data extracted for meta-analysis were analyzed using comprehensive meta-analysis version 3. Trends data for the isolation rate and resistance rates were entered into Excel spread sheet and the results were presented in graphs.

RESULTS

The prevalence rate of drug resistance in K. pneumoniae were; amikacin (40.8%) [95% CI 31.9-50.4], aztreonam (73.3%) [95% CI 59.9-83.4], ceftazidime (75.7%) [95% CI 65.4-83.6], ciprofloxacin (59.8%) [95% CI 48.6-70.1], colistin (2.9%) [95% CI 1.8-4.4], cefotaxime (79.2%) [95% CI 68.0-87.2], cefepime (72.6) [95% CI 57.7-83.8] and imipenem (65.6%) [95% CI 30.8-89.0]. TEM (39.5%) [95% CI 15.4-70.1], SHV-11 (41.8%) [95% CI 16.2-72.6] and KPC-2 (14.6%) [95% CI 6.0-31.4] were some of the resistance mediated genes observed in this study. The most virulent factors utilized by K. pneumoniae are; hypermucoviscous phenotype and mucoviscosity-related genes, genes for biosynthesis of lipopolysaccharide, iron uptake and transport genes and finally, adhesive genes.

CONCLUSION

It can be concluded that, antimicrobial resistant in K. pneumoniae is a clear and present danger in Asia which needs strong surveillance to curb this menace. It is very important for public healthcare departments to monitor and report changes in antimicrobial-resistant isolates.

Risk factors and survival of patients infected with carbapenem-resistant Klebsiella pneumoniae in a KPC endemic setting: a case-control and cohort study

BACKGROUND

Many gaps in the burden of resistant pathogens exist in endemic areas of low- and middle-income economies, especially those endemic for carbapenem resistance. The aim of this study is to evaluate risk factors for carbapenem-resistance, to estimate the association between carbapenem-resistance and all-cause 30-day mortality and to examine whether mortality is mediated by inappropriate therapy.

METHODS

A case-control and a cohort study were conducted in one tertiary-care hospital in Medellín, Colombia from 2014 to 2015. Phenotypic and genotypic characterization of isolates was performed. In the case-control study, cases were defined as patients infected with carbapenem-resistant K. pneumoniae (CRKP) and controls as patients infected with carbapenem-susceptible K. pneumoniae (CSKP). A risk factor analysis was conducted using logistic regression models. In the cohort study, the exposed group was defined as patients infected with CRKP and the non-exposed group as patients infected with CSKP. A survival analysis using an accelerated failure time model with a lognormal distribution was performed to estimate the association between carbapenem resistance and all-cause 30-day-mortality and to examine whether mortality is mediated by inappropriate therapy.

RESULTS

A total of 338 patients were enrolled; 49 were infected with CRKP and 289 with CSKP. Among CRKP isolates CG258 (n = 29), ST25 (n = 5) and ST307 (n = 4) were detected. Of importance, every day of meropenem (OR 1.18, 95%CI 1.10-1.28) and cefepime (OR 1.22, 95%CI 1.03-1.49) use increase the risk of carbapenem resistance. Additional risk factors were previous use of ciprofloxacin (OR 2.37, 95%CI 1.00-5.35) and urinary catheter (OR 2.60, 95%CI 1.25-5.37). Furthermore, a significant lower survival time was estimated for patients infected with CRKP compared to CSKP (Relative Times 0.44, 95%CI 0.24-0.82). The strength of association was reduced when appropriate therapy was included in the model (RT = 0.81 95%CI 0.48-1.37).

CONCLUSION

Short antibiotic courses had the potential to reduce the selection and transmission of CRKP. A high burden in mortality occurred in patients infected with CRKP in a KPC endemic setting and CRKP leads to increased mortality via inappropriate antibiotic treatment. Furthermore, dissemination of recognized hypervirulent clones could add to the list of challenges for antibiotic resistance control.

Risk factors for carbapenem-resistant Klebsiella pneumoniae infection: A meta-analysis

OBJECTIVES

Rates of nosocomial infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) have increased. A meta-analysis was conducted to explore risk factors for CRKP infection in order to provide a theoretical basis for reducing the CRKP infection rate and actively preventing CRKP infection.

METHODS

Online databases, including PubMed, EMBASE, OVID, ClinicalKey, CNKI, CBM, Wanfang Database and CHKD, were searched from inception up to 31 October 2018 for articles regarding risk factors for CRKP infection. Relevant articles were retrieved, supplemented by retrospective and manual search literature. RevMan 5.3 software was used for statistical analysis.

RESULTS

A total of 30 articles comprising 5075 cases were included in the study, of which 24 were in English and 6 were in Chinese. The results showed that age, sex and diabetes mellitus were not associated with CRKP infection. The odds ratio (95% confidence interval) of risk factors for CRKP infection were as follows: immunosuppression, 1.47 (1.14-1.90); ICU admission, 3.25 (2.36-4.47); antibiotic exposure, 2.53 (1.56-4.11); carbapenem exposure, 3.99 (2.86-5.56); quinolone exposure, 1.75 (1.38-2.22); glycopeptide exposure, 3.08 (1.93-4.91); β‑lactam/β‑lactamase inhibitor (BL/BLI) exposure, 2.28 (1.37-3.80); surgery, 1.59 (1.08-2.34); mechanical ventilation, 2.91 (1.96-4.31); central venous catheterisation, 2.93 (2.00-4.28); indwelling catheter, 2.62 (1.65-4.17); and nasogastric intubation, 2.38 (1.22-4.62).

CONCLUSION

Immunosuppression, ICU admission, antibiotic exposure (including carbapenems, quinolones, glycopeptides and BL/BLIs), surgery, mechanical ventilation, central venous catheterisation, indwelling catheter and nasogastric intubation were identified as risk factors for CRKP infection and should to be considered in clinical practice.

Bystander Selection for Antimicrobial Resistance: Implications for Patient Health

Antimicrobial therapy promotes resistance emergence in target infections and in off-target microbiota. Off-target resistance emergence threatens patient health when off-target populations are a source of future infections, as they are for many important drug-resistant pathogens. However, the health risks of antimicrobial exposure in off-target populations remain largely unquantified, making rational antibiotic stewardship challenging. Here, we discuss the contribution of bystander antimicrobial exposure to the resistance crisis, the implications for antimicrobial stewardship, and some novel opportunities to limit resistance evolution while treating target pathogens.

Influence of primary care antibiotic prescribing on incidence rates of multidrug-resistant Gram-negative bacteria in hospitalised patients

PURPOSE

Use of antibiotics can give rise to the selection of resistant bacteria. It remains unclear whether antibiotic use in primary care can influence bacterial resistance incidence in patients when hospitalised. The aim of this study is to explore the impact of prior community antibiotic usage on hospital-detected multidrug-resistant Gram-negative (MRGN) incidence rate.

METHODS

This pharmacoepidemiological study was case-control in design, and was carried out in the Antrim Area Hospital (N. Ireland) in two phases. In phase 1, the controls were matched according to: age, gender, admission ward, date of admission, and age-adjusted Charlson co-morbidity index score. During the second phase, controls were selected randomly from the total population of admissions to the hospital over the 2-year study period.

RESULTS

In phase 1, multivariate analysis revealed that prior exposure to the second- and third-generation cephalosporins (p = 0.004) and fluoroquinolones (p = 0.023) in primary care was associated with an increased likelihood of MRGN detection in inpatients. In phase 2, an independent relationship between an increased risk of identification of MRGN, while hospitalised was associated with: prolonged hospitalisation (p < 0.001), being elderly (p < 0.001), being female (p = 0.007), and having genitourinary disease (p < 0.001).

CONCLUSION

This study provides clear evidence which supports the need to optimise antibiotic use in primary care to help reduce MRGN incidence in hospitalised patients.

ESBL-colonization at ICU admission: impact on subsequent infection, carbapenem-consumption, and outcome

OBJECTIVE

To determine whether colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) predicts the risk for subsequent infection and impacts carbapenem-consumption and outcome in intensive care unit (ICU) patients.

DESIGN

Prospective cohort study.

SETTING

The 2 ICUs in the University Hospital Basel in Switzerland.

PATIENTS

All patients admitted to the 2 ICUs providing mechanical ventilation and an expected ICU stay &gt;48 hours.

METHODS

Patients were routinely screened for ESBL-PE carriage by rectal swab on admission. Competing risk regression analyses were applied to calculate hazard ratios (HRs) for infection with ESBL-PE and mortality. Length of hospital stay, length of ICU stay, and duration of carbapenem exposure were compared using the Mann-Whitney U test.

RESULTS

Among 302 patients, 24 (8.0%) were colonized with ESBL-PE on ICU admission. Infections with ESBL-PE occurred in 4 patients, of whom 3 (75%) were identified as ESBL-PE colonized on admission. ESBL-PE colonization on admission was associated with subsequent ESBL-PE infection (hazard ratio [HR], 25.52; 95% confidence interval [CI], 2.40-271.41; P = .007) and exposure to carbapenems (HR, 2.42; 95% CI, 1.01-5.79; P = .047), whereas duration of carbapenem exposure did not differ in relation to ESBL-PE colonization (median, 7 days [IQR, 3-8 days] vs median, 6 days [IQR 3-9 days]; P = 0.983). Patients colonized with ESBL-PE were not at increased risk for death overall (HR, 1.00; 95% CI, 0.44-2.30; P = .993) or death attributable to infection (HR, 1.20; 95% CI, 0.28-5.11; P = .808).

CONCLUSIONS

Screening strategies for detection of ESBL-PE colonization on ICU admission may allow the identification of patients at highest risk for ESBL-PE infection and the correct allocation of empiric carbapenem treatment.

Epidemiology of and risk factors for infection with extended-spectrum β-lactamase-producing carbapenem-resistant Enterobacteriaceae: results of a double case-control study

Purpose

Carbapenem-resistant Enterobacteriaceae (CRE) have been increasingly reported worldwide and pose a serious public threat, but the clinical significance of extended-spectrum β-lactamase (ESBL) production in CRE is not well established.

Patients and methods

A retrospective case–case–control study was conducted to identify the clinical characteristics of patients with ESBL-CRE. The susceptibility of isolates obtained from these patients was assessed. The detection of ESBL and carbapenemase-related genes was performed by PCR methods. Predictors of 30-day mortality in patients with ESBL-CRE infection were also identified in our study.

Results

A total of 149 patients with CRE infection caused by Enterobacter cloacae (n=74), Escherichia coli (n=38), and Klebsiella pneumoniae (n=37) were identified in Chongqing, Southwestern China, between January 2011 and December 2014. Of the 35 isolates detected with carbapenemase-related genes, 16 isolates had New Delhi metallo-β-lactamase (NDM), nine isolates had K. pneumoniae carbapenemase (KPC), seven isolates had imipenemase (IMP), and four isolates had oxacillinase (OXA)-1. One strain of enterobacter cloacae carried both NDM-1 and IMP-8 genes. ESBL isolates included the genes CTX-M (72/149), SHV (64/149), and TEM (54/149). All ESBL-CRE isolates exhibited ertapenem resistance, and the rate of cephalosporin resistance was relatively high in general. Independent risk factors for infection with ESBL-CRE included previous exposure to β-lactam antibiotics, transfer from another hospital, and some underlying diseases. In addition, solid tumors, hypoalbuminemia, and central venous catheters were independent predictors of mortality in patients with ESBL-CRE infection.

Conclusion

Physicians should understand the peculiar predictors for the identification of these organisms among high-risk patients.

Predictors of the extended-spectrum-beta lactamases producing Enterobacteriaceae neonatal sepsis at a tertiary hospital, Tanzania

•

ESBL-PE sepsis was predicted by admission at ICU and ESBL-PE colonization.

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Neonates infected with ESBL-PE had significantly high mortality.

•

ESBL-producing Klebsiella pneumoniae (ST45) carrying bla_CTX-M-15 were predominant.

•

Whole genome SNP analysis revealed clonal origin in 50% of ESBL-PE paired cases with similar sequence type.

The study was conducted to establish predictors of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) neonatal sepsis and mortality in a tertiary hospital, Tanzania. Between July and December 2016, blood culture was performed in neonates with clinical features of sepsis and neonates/mothers/guardians were screened for ESBL colonization. Selected isolates underwent whole genome sequencing to investigate relatedness. Logistic regression analysis was performed to determine predictors for ESBL-PE associated neonatal sepsis and mortality. Neonatal ESBL-PE sepsis was detected in 32(10.5%) of the 304 neonates investigated. Neonatal ESBL-PE sepsis was independently predicted by admission at the Intensive care Unit and positive mother and neonate ESBL-PE colonization. Deaths occurred in 55(18.1%) of neonates. Neonates infected with ESBL-PE, admitted at ICU, increased age and those transferred from other centres had significantly high mortality rates. Gram-negative bacteria formed the majority (76%) of the isolates, of which 77% were ESBL-PE. Virulent Klebsiella pneumoniae ST45 carrying bla_CTX-M-15 were commonly isolated from neonates. Klebsiella pneumoniae (ST45) were the predominant cause of ESBL-PE neonatal sepsis and mortality. Improved infection control and antibiotic stewardship are crucial in controlling the spread of resistant strains. Rapid diagnostic tests to detect ESBL-PE in low-income countries are needed to guide treatment and reduce ESBL-PE-associated mortality.

Risk Factors for Carbapenem-Resistant Klebsiella pneumoniae Infection: A Meta-Analysis

AIMS

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection has been rapidly emerging as a life-threatening nosocomial disease in many countries. However, studies on the corresponding risk factors of CRKP infection showed inconsistent results. To resolve these inconsistencies, we conducted a meta-analysis of previous studies on the potential risk factors of CRKP infection. The results of this study could be used to develop CRKP infection prevention strategies.

METHODS

Relevant works were systematically searched from five electronic databases up to September 2016. Z-test was used to determine the significance of the pooled odds ratios (ORs). ORs and 95% confidence intervals were utilized to compare the risk factors of CRKP infection.

RESULTS

Sixteen studies that involved 3,627 participants were included in the meta-analysis. We identified the following risk factors that were associated with CRKP infection: (1) longer length of hospital stay (LOS) (OR = 12.92), (2) admission to intensive care unit (ICU) (OR = 2.48), (3) prior hospitalization (OR = 1.85), (4) longer days of ICU stay (OR = 4.58), (5) transplant recipient (OR = 2.01), (6) steroid use (OR = 1.43), (7) central venous catheter use (OR = 2.30), (8) mechanical ventilation (OR = 2.54), (9) presence of tracheostomy (OR = 3.63), (10) parenteral nutrition (OR = 2.38), (11) previous antibiotic use (OR = 3.31), and (12) exposure to carbapenems (OR = 4.01), (13) aminoglycosides (OR = 2.05), (14) glycopeptides (OR = 2.40), (15) quinolones (OR = 2.28), and (16) anti-pseudomonal penicillins (OR = 2.67).

CONCLUSIONS

Sixteen risk factors including longer LOS, admission to ICU, previous antibiotic use, and exposure to carbapenems were associated with the development of CRKP infection. Identification of modifiable risk factors could play an important role in the prevention of CRKP infection.

High-dose tigecycline for the treatment of nosocomial carbapenem-resistant Klebsiella pneumoniae bloodstream infections: A retrospective cohort study

Carbapenem-resistant Klebsiella pneumoniae (CRKP) bloodstream infection (BSI) has become increasingly frequent threat recently, especially in the intensive care unit (ICU). High-dose tigecycline (TGC) regimen is proposed due to the limitation of treatment options. We investigated the efficacy and safety of high-dose TGC combination regimens for treating CRKP BSI. Furthermore, the risk factors for mortality were also determined.This was a single center retrospective cohort study conducted from 2014 to 2016. A total of 40 patients with nosocomial CRKP BSI admitted to the ICU were included; they were classified into two groups according to the treatment regimens with high-dose TGC (HD group) or not (non-HD group). In-hospital mortality rates and microbiologic responses from both groups were reviewed and compared. Besides, the survival and non-survival groups were compared to identify the risk factors of mortality.Twenty-three patients constituted the HD group (high-dosage TGC regimen was administered as 200 mg loading dose followed by 100 mg every 12 h) and 17 patients constituted the non-HD group (standard dose TGC therapy as 100 mg loading dose followed by 50 mg every 12 h and other antibiotics). The in-hospital mortality was 52.2% in the HD group and 76.5% in the non-HD group (P = .117). The Kaplan-Meier test showed significantly longer survival times in the HD group (mean: 83 days vs 28 days; P = .027). Microbiological eradication was observed in 13 patients (56.5%) in the HD group and 6 patients (36.3%) in the non-HD group (P = .184). A smaller fraction of patients in the HD group were subjected to vasoactive therapy (52.2% vs 88.2%; P = .016) compared to the non-HD group. There was no significant difference in the manifestation of adverse effects between the two groups. In the multivariate analysis, multiple organ dysfunction syndrome (MODS), vasoactive therapy, and exposure to carbapenems were regarded as the independent predictors of mortality.A therapeutic regimen consisting of a high dose of TGC was associated with significantly longer survival time and numerically lower mortality in CRKP BSI. Adverse events were not increased with the double dose therapy.

Clinical and Molecular Epidemiology of Carbapenem-Resistant Enterobacteriaceae Among Adult Inpatients in Singapore

Background

Since 2010, the incidence of carbapenem-resistant Enterobacteriaceae (CRE) has been increasing in Singapore. We analyzed the clinical and molecular epidemiology of CRE among adult inpatients in Singapore.

Methods

Quarterly incidence of unique subjects (per 100000 patient-days) with positive clinical and surveillance cultures for CRE were estimated based on mandatory data submitted to the National Public Health Laboratory by public hospitals between 2010 and 2015. CRE-positive adult inpatients were prospectively recruited from 6 public sector hospitals between December 2013 and April 2015. Subjects answered a standardized epidemiologic questionnaire and provided samples for this study. Further clinical information was extracted from subjects' electronic medical records. Whole-genome sequencing was performed on study isolates to determine transmission clusters.

Results

Incidence of CRE clinical cultures among adult inpatients plateaued from 2013 (range: 7.73 to 10.32 per 100000 patient-days) following an initial increase between 2010 and end-2012. We prospectively recruited 249 subjects. Their median age was 65 years, 108 (43%) were female, and 161 (64.7%) had carbapenemase-producing Enterobacteriaceae (CPE). On multivariate analysis, prior carbapenem exposure (OR: 3.23; 95% CI: 1.67-6.25) and hematological malignancies (OR: 2.85; 95% CI: 1.10-7.41) were associated with non-carbapenemase-producing CRE (NCPE) (n = 88) compared with CPE (n = 161) subjects. Among 430 CRE isolates from the 249 subjects, 307(71.3%) were CPE, of which 154(50.2%) were blaKPC-positive, 97(31.6%) blaNDM-positive, and 42 (13.7%) blaOXA-positive. Klebsiella pneumoniae (n = 180, 41.9%), Escherichia coli (n = 129, 30.0%) and Enterobacter cloacae (n = 62, 14.4%) were the main Enterobacteriaceae species. WGS (n = 206) revealed diverse bacterial strain type (STs). The predominant blaKPC-positive plasmid was pHS102707 (n = 62, 55.4%) and the predominant blaNDM-positive plasmid was pNDM-ECS01 (n = 46, 48.9%). Five transmission clusters involving 13 subjects were detected.

Conclusions

Clinical CRE trend among adult inpatients showed stabilization following a rapid rise since introduction in 2010 potentially due to infection prevention measures and antimicrobial stewardship. More work is needed on understanding CPE transmission dynamics.

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.

Multicenter Study of the Risk Factors for Colonization or Infection with Carbapenem-Resistant Enterobacteriaceae in Children

Carbapenem-resistant Enterobacteriaceae (CRE) are increasingly identified in children in the United States, but data on the epidemiology of CRE in this population are limited. The objectives of this study were to characterize the risk factors for colonization or infection with CRE and describe the microbiologic characteristics of pediatric CRE isolates. We performed a multicenter matched case-control study from January 2011 to October 2015 at three tertiary care pediatric centers. Case patients were hospitalized children with CRE isolated from clinical cultures and were matched in a 2:1 ratio to control patients with carbapenem-susceptible Enterobacteriaceae (CSE). Risk factors for colonization or infection with CRE were then evaluated using a multivariable conditional logistic regression. Additionally, we comprehensively reported the antimicrobial susceptibility pattern for CRE isolates. Sixty-three case patients were identified and matched to 126 control patients. On multivariable analysis, antipseudomonal antibiotic exposure within the previous 3 months (odds ratio [OR], 5.20; 95% confidence interval [CI], 1.71 to 15.9; P = 0.004), prior surgery (OR, 6.30; 95% CI, 1.83 to 21.6; P = 0.003), and mechanical ventilation (OR, 12.4; 95% CI, 1.26 to 122; P = 0.031) were identified as risk factors for colonization or infection with CRE. Pediatric CRE isolates demonstrated relatively low rates of resistance to amikacin (5%) and ciprofloxacin (25%). Our findings support an important role for antibiotic stewardship interventions limiting the unnecessary use of antipseudomonal antibiotics as a strategy to prevent widespread emergence of CRE in children. Future studies should further characterize molecular determinants of antibiotic resistance among pediatric CRE isolates.

An update on new antibiotic prophylaxis and treatment for urinary tract infections in children

INTRODUCTION

This review focuses on the treatment of urinary tract infections (UTI) in children and in particular its recent changes. Areas covered: Acute pyelonephritis, acute cystitis and asymptomatic bacteriuria or asymptomatic infections have to be clearly distinguished. Prompt treatment is required in pyelonephritis and cystitis, but not in asymptomatic bacteriuria or infection, in order to avoid selection of more virulent strains. This concept should be considered even in immunocompromised or bedridden children. In case of pyelonephritis, there should be no delay in beginning the antibiotic treatment in order to decrease the risk of long term complication, such as renal scars. Predisposing conditions for UTI, such as voiding anomalies and urinary tract malformation should be carefully evaluated. Expert opinion: One major concern is the increasing resistance to 3^rd generation cephalosporins. Therefore overconsumption in low-risk settings should be absolutely avoided. The prevalence of infections with E. coli producing extended spectrum ß-lactamase (ESBL) is increasing and pediatricians should be aware about the specific treatment options. Any recommendation about (initial) antibiotic treatment should be regularly updated and adapted to local resistance profiles and to economic factors in different health systems.

The Continuing Plague of Extended-spectrum β-lactamase-producing Enterobacteriaceae Infections

Antimicrobial resistance is a common iatrogenic complication of modern life and medical care. One of the most demonstrative examples is the exponential increase in the incidence of extended-spectrum β-lactamases (ESBLs) production among Enterobacteriaceae, which is the most common human pathogens outside of the hospital settings. Infections resulting from ESBL-producing bacteria are associated with devastating outcomes, now affecting even previously healthy individuals. This development poses an enormous burden and threat to public health. This paper aims to narrate the evolving epidemiology of ESBL infections, and highlight current challenges in terms of management and prevention of these common infections.

Routine Ertapenem Prophylaxis for Transrectal Ultrasound Guided Prostate Biopsy does Not Select for Carbapenem Resistant Organisms: A Prospective Cohort Study

PURPOSE

Sepsis after transrectal ultrasound guided prostate biopsy is an increasing problem in this era of rising antibiotic resistance. Although ertapenem prophylaxis has proved effective at our institution to reduce this, it has raised local and regional antimicrobial stewardship concerns. We investigated the possible selective effect of single dose ertapenem prophylaxis on fecal colonization with carbapenem resistant Enterobacteriaceae.

MATERIALS AND METHODS

Patients underwent a rectal swab prior to receiving prebiopsy ertapenem prophylaxis. A second swab was obtained at followup 4 to 6 weeks later. Swabs were screened for carbapenem resistant Enterobacteriaceae using an enhanced CDC (Centers for Disease Control) method. Prebiopsy swabs were also screened for extended spectrum β-lactamase producing and ciprofloxacin resistant Enterobacteriaceae. Patients were monitored for post-biopsy sepsis.

RESULTS

A total of 326 patients were enrolled in the study. At baseline 6.4% and 9.0% of patients had colonization with extended spectrum β-lactamase producing and ciprofloxacin resistant Enterobacteriaceae, respectively. Carbapenem resistant Enterobacteriaceae were not detected at baseline or followup in any patients. Colonization with nonfermentative organisms with intrinsic ertapenem resistance was detected in 29.4% of patients at baseline and followup (p = 1.0). Three cases (0.9%, 95% CI 0.2-2.8) of probable post-biopsy sepsis were identified during the study period. None was bacteremic or required intensive care unit admission.

CONCLUSIONS

Single dose ertapenem prophylaxis did not appear to have a significant selective effect on fecal colonization with carbapenem resistant Enterobacteriaceae or other ertapenem resistant gram-negative organisms in this outpatient group. It is highly effective prophylaxis for transrectal ultrasound guided prostate biopsy. In the right setting ertapenem may represent a useful prophylactic option to prevent post-transrectal ultrasound guided prostate biopsy sepsis.

Risk factors and medical costs for healthcare-associated carbapenem-resistant Escherichia coli infection among hospitalized patients in a Chinese teaching hospital

Background

The emergence and spread of Carbapenem-resistant Escherichia coli (CREC) is becoming a serious problem in Chinese hospitals, however, the data on this is scarce. Therefore, we investigate the risk factors for healthcare-associated CREC infection and study the incidence, antibiotic resistance and medical costs of CREC infections in our hospital.

Methods

We conducted a retrospective, matched case–control–control, parallel study in a tertiary teaching hospital. Patients admitted between January 2012 and December 2015 were included in this study. For patients with healthcare-associated CREC infection, two matched subject groups were created; one group with healthcare-associated CSEC infection and the other group without infection.

Results

Multivariate conditional logistic regression analysis demonstrated that prior hospital stay (<6 months) (OR:3.96; 95%CI:1.26–12.42), tracheostomy (OR:2.24; 95%CI: 1.14–4.38), central venous catheter insertion (OR: 8.15; 95%CI: 2.31–28.72), carbapenem exposure (OR: 12.02; 95%CI: 1.52–95.4), urinary system disease (OR: 16.69; 95%CI: 3.01–89.76), low hemoglobin (OR: 2.83; 95%CI: 1.46–5.50), and high blood glucose are associated (OR: 7.01; 95%CI: 1.89–26.02) with CREC infection. Total costs (p = 0.00), medical examination costs (p = 0.00), medical test costs (p = 0.00), total drug costs (p = 0.00) and ant-infective drug costs (p = 0.00) for the CREC group were significantly higher than those for the no infection group. Medical examination costs (p = 0.03), total drug costs (p = 0.03), and anti-infective drug costs (p = 0.01) for the CREC group were significantly higher than for the CSEC group. Mortality in CREC group was significantly higher than the CSEC group (p = 0.01) and no infection group (p = 0.01).

Conclusion

Many factors were discovered for acquisition of healthcare-associated CREC infection. CREC isolates were resistant to most antibiotics, and had some association with high financial burden and increased mortality.

Risk factors and molecular epidemiology of community-onset, multidrug resistance extended-spectrum β-lactamase-producing Escherichia coli infections

BACKGROUND/AIMS

Although multidrug resistance (MDR) among extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) poses significant therapeutic challenges, little is known regarding the risk factors and epidemiology of community-onset MDR-ESBL-EC infections. We performed this study to investigate risk factors and the molecular epidemiology of community-onset MDR-ESBL-EC infections.

METHODS

We conducted a case-control-control study of community-onset infections. MDR-ESBL-EC was defined as ESBL-EC that demonstrated in vitro resistance to trimethoprim-sulfamethoxazole, fluoroquinolones (FQs), and gentamicin. Patients with MDR-ESBL-EC infections were designated as case patients. A control group I (CG I) patient was defined as a person whose clinical sample yielded ESBL-EC that did not meet the criteria for MDR. A control group II (CG II) patient was defined as a patient with a non-ESBL-EC infection.

RESULTS

Of 108 patients with ESBL-EC infections, 30 cases (27.8%) were due to MDR-ESBL-EC. Compared with CG I, prior use of FQs (odds ratio [OR], 3.16; 95% confidence interval [CI], 1.11 to 8.98) and immunosuppressant use (OR, 10.47; 95% CI, 1.07 to 102.57) were significantly associated with MDR-ESBL-EC. Compared with CG II, prior use of FQs (OR, 15.53; 95% CI, 2.86 to 84.27) and healthcare-associated infection (OR, 5.98; 95% CI, 2.26 to 15.86) were significantly associated with MDR-ESBL-EC. CTX-M-15 was the most common in MDR-ESBL-EC infections (59.1% [13/22]), while CTX-M-14 was the most common in non-MDR-ESBL-EC infections (41.6% [32/77]). CTX-M-15 was significantly associated with MDR-ESBL-EC (59.1% vs. 32.5%, p = 0.028). Pulsed-field gel electrophoresis showed clonal diversity of MDR-ESBL-EC isolates.

CONCLUSIONS

The emergence of strains of MDR-ESBL-EC in the community poses an important new public health threat. More information on the emergence and transmission of these strains will be necessary in order to prevent their spread.

Clinical epidemiology, treatment and prognostic factors of extensively drug-resistant Acinetobacter baumannii ventilator-associated pneumonia in critically ill patients

Limited data exist regarding prognostic factors and optimal antimicrobial treatment of infections caused by extensively drug-resistant Acinetobacter baumannii (XDR-AB). This retrospective cohort study included 93 adult patients who developed ventilator-associated pneumonia (VAP) due to XDR-AB in the ICU of the University Hospital of Heraklion, Greece, from October 2012 to April 2015. XDR-AB isolates were mainly susceptible to colistin (93.5%) and tigecycline (25.8%), whereas 6 (6.5%) were pandrug-resistant. Prior to infection, patients had long durations of mechanical ventilation and hospital stay and multiple exposures to antibiotics. Median Charlson co-morbidity and APACHE II scores were 2 and 17, respectively. Mortality at 28 days of infection onset was high (34.4%) despite high rates of in-vitro-active empirical (81.7%) and definitive (90.3%) treatment. Active colistin-based combination therapy (n = 55) and monotherapy (n = 29) groups had similar 28-day mortality (27.6% vs. 30.9%, respectively) and Kaplan-Meier survival estimates over time. In multivariable Cox regression, advanced age (aHR = 1.05 per year increase, 95% CI 1.02-1.09), rapidly fatal underlying disease (aHR = 2.64, 95% CI 0.98-9.17) and APACHE II score (aHR = 1.06 per unit increase, 95% CI 0.99-1.14) were identified as independent predictors of 28-day mortality, but no difference in mortality hazards between the active colistin-based combination therapy and monotherapy groups was produced (aHR = 0.88, 95% CI 0.35-2.38). These results support the use of colistin as a first-line agent against VAP in settings where XDR-AB is endemic, but oppose the introduction of colistin-based combination therapy as standard treatment.

Clinical and Molecular Characteristics of Neonatal Extended-Spectrum β-Lactamase-Producing Gram-Negative Bacteremia: A 12-Year Case-Control-Control Study of a Referral Center in Taiwan

Extended-spectrum β-lactamase (ESBL)-producing Gram-negative bacteremia (GNB) in the neonatal intensive care unit was characterized by comparison with two control groups: a susceptible control group and a general base population group over 2001 to 2012. The influence of ESBL production on mortality was studied in all study subjects and ESBL-GNB isolates were microbiologically characterized. We identified 77 episodes of ESBL-GNB (14.2% of all neonatal late-onset GNB), which were caused by Klebsiella spp. (62.3%), E. coli (20.8%) and Enterobacter spp. (16.9%). Most ESBL-GNB strains were genetically unrelated and the SHV-type ESBLs were the most prevalent (67% of isolates). Comparison with both control groups disclosed previous usage of 3^rd generation cephalosporin (odds ratio [OR], 4.72; 95% confidence interval [CI], 2.03–10.97; P < 0.001), and underlying renal disease (OR, 4.07; 95% CI, 1.10–15.08; P = 0.035) as independent risk factors for ESBL-GNB. Inadequate empiric antibiotics, a higher illness severity, higher rates of infectious complications and sepsis-attributable mortality were more frequently seen in neonates with ESBL-GNB than those with non-ESBL GNB (20.8% and 15.6% vs. 9.2% and 7.9%, respectively; P = 0.008 and 0.049, respectively). Neonates with underlying secondary hypertension (OR, 7.22; 95% CI, 2.17–24.06) and infectious complications after bacteremia (OR, 6.66; 95% CI, 1.81–19.31) were identified as independent risk factor for in-hospital mortality. ESBL-GNB accounted for one-seventh of all neonatal gram-negative bacteremia, especially in neonates exposed to broad-spectrum cephalosporins. Neonates with ESBL-GNB bacteremia more frequently received inadequate empirical antibiotic therapy, which were associated with a higher rate of infectious complications and an adverse outcome.

Risk factors and clinical outcomes for carbapenem-resistant Enterobacteriaceae nosocomial infections

This study was aimed to determine the risk factors of Carbapenem-resistant Enterobacteriaceae (CRE) nosocomial infections and assess the clinical outcomes. A case-case-control design was used to compare two groups of case patients with control patients from March 2010 to November 2014 in China. Risk factors for the acquisition of CRE infections and clinical outcomes were analyzed by univariable and multivariable analysis. A total of 94 patients with CRE infections, 93 patients with Carbapenem-susceptible Enterobacteriaceae (CSE) infections, and 93 patients with organisms other than Enterobacteriaceae infections were enrolled in this study. Fifty-five isolates were detected as the carbapenemase gene. KPC-2 was the most common carbapenemase (65.5 %, 36/55), followed by NDM-1 (16.4 %, 9/55), IMP-4 (14.5 %, 8/55), NDM-5 (1.8 %, 1/55), and NDM-7 (1.8 %, 1/55). Multivariable analysis implicated previous use of third or fourth generation cephalosporins (odds ratio [OR], 4.557; 95 % confidence interval [CI], 1.971-10.539; P < 0.001) and carbapenems (OR, 4.058; 95 % CI, 1.753-9.397; P = 0.001) as independent risk factors associated with CRE infection. The in-hospital mortality of the CRE group was 57.4 %. In the population of CRE infection, presence of central venous catheters (OR, 4.464; 95 % CI, 1.332-14.925; P = 0.015) and receipt of immunosuppressors (OR, 7.246; 95 % CI, 1.217-43.478; P = 0.030) were independent risk factors for mortality. Appropriate definitive treatment (OR, 0.339; 95 % CI, 0.120-0.954; P = 0.040) was a protective factor for in-hospital death of CRE infection. Kaplan-Meier curves of the CRE group had the shortest survival time compared with the other two groups. Survival time of patients infected with Enterobacteriaceae with a high meropenem MIC (≥8 mg/L) was shorter than that of patients with a low meropenem MIC (2,4, and ≤ 1 mg/L). In conclusion, CRE nosocomial infections are associated with prior exposure to third or fourth generation cephalosporins and carbapenems. Patients infected with CRE had poor outcome and high mortality, especially high meropenem MIC (≥8 mg/L). Appropriate definitive treatment to CRE infections in the patient is essential.

Antibiotic strategies in the era of multidrug resistance

The rapid emergence and dissemination of antibiotic-resistant microorganisms in ICUs worldwide threaten adequate antibiotic coverage of infected patients in this environment. The causes of this problem are multifactorial, but the core issues are clear: the emergence of antibiotic resistance is highly correlated with selective pressure resulting from inappropriate use of these drugs. Because a significant increase in mortality is observed when antibiotic therapy is delayed in infected ICU patients, initial therapy should be broad enough to cover all likely pathogens. Receipt of unnecessary prolonged broad-spectrum antibiotics, however, should be avoided. Local microbiologic data are extremely important to predict the type of resistance that may be present for specific causative bacteria, as is prior antibiotic exposure, and antibiotic choices should thus be made at an individual patient level.

Leveraging antimicrobial stewardship into improving rates of carbapenem-resistant Enterobacteriaceae

Carbapenem-resistant Enterobacteriaceae (CRE) are among the most critical threats facing our healthcare system and account for significant patient mortality. There is considerable interest in the development of new treatment strategies. However, less attention has been paid to reducing CRE infection rates. Antibiotic stewardship programs can be uniquely empowered to reduce widespread pathogen resistance and by extension, optimize patient care and lower healthcare costs.