Risk factors of carbapenem-resistant Klebsiella pneumoniae infection: a serious threat in ICUs

Vaccine value profile for Klebsiella pneumoniae

Klebsiella pneumoniae causes community- and healthcare-associated infections in children and adults. Globally in 2019, an estimated 1.27 million (95% Uncertainty Interval [UI]: 0.91-1.71) and 4.95 million (95% UI: 3.62-6.57) deaths were attributed to and associated with bacterial antimicrobial resistance (AMR), respectively. K. pneumoniae was the second leading pathogen in deaths attributed to AMR resistant bacteria. Furthermore, the rise of antimicrobial resistance in both community- and hospital-acquired infections is a concern for neonates and infants who are at high risk for invasive bacterial disease. There is a limited antibiotic pipeline for new antibiotics to treat multidrug resistant infections, and vaccines targeted against K. pneumoniae are considered to be of priority by the World Health Organization. Vaccination of pregnant women against K. pneumoniae could reduce the risk of invasive K.pneumoniae disease in their young offspring. In addition, vulnerable children, adolescents and adult populations at risk of K. pneumoniae disease with underlying diseases such as immunosuppression from underlying hematologic malignancy, chemotherapy, patients undergoing abdominal and/or urinary surgical procedures, or prolonged intensive care management are also potential target groups for a K. pneumoniae vaccine. A 'Vaccine Value Profile' (VVP) for K.pneumoniae, which contemplates vaccination of pregnant women to protect their babies from birth through to at least three months of age and other high-risk populations, provides a high-level, holistic assessment of the available information to inform the potential public health, economic and societal value of a pipeline of K. pneumoniae vaccines and other preventatives and therapeutics. This VVP was developed by a working group of subject matter experts from academia, non-profit organizations, public-private partnerships, and multi-lateral organizations, and in collaboration with stakeholders from the WHO. All contributors have extensive expertise on various elements of the K.pneumoniae VVP and collectively aimed to identify current research and knowledge gaps. The VVP was developed using only existing and publicly available information.

Risk factors and mortality rates of carbapenem-resistant Gram-negative bacterial infections in intensive care units

Background

The prevalence of hospital-acquired infections caused by carbapenem-resistant gram-negative bacteria (CRGNB) is increasing worldwide. Several risk factors have been associated with such infections. The present study aimed to identify risk factors and determine the mortality rates associated with CRGNB infections in intensive care units.

Methods

This retrospective case-control study was conducted at Erciyes University Hospital (Kayseri, Turkey) between January 2017 and December 2021. Demographic and laboratory data were obtained from the Infection Control Committee data and record system. Patients who had CRGNB infection 48-72 h after hospitalization were assigned to the case group, while those who were not infected with CRGNB during hospitalization formed the control group. Risk factors, comorbidity, demographic data, and mortality rates were compared between the two groups.

Results

Approximately 1449 patients (8.97%) were monitored during the active follow-up period; of those, 1171 patients were included in this analysis. CRGNB infection developed in 14 patients (70.00%) who had CRGNB colonization at admission; in 162 (78.26%) were colonized during hospitalization, whereas 515 (54.56%) were not colonized. There was no significant difference in age, sex (male/female) or comorbidities. The total length of hospital stay was statistically significantly longer (P=0.001) in the case group (median: 24 [interquartile range: 3-378] days) than the control group (median: 16 [interquartile range: 3-135] days). The rates of colonization at admission (25.5%; vs. 10.6%, P=0.001) and mortality (64.4% vs. 45.8%, P=0.001) were also significantly higher in the cases than in the control group, respectively. In the univariate analysis, prolonged hospitalization, the time from intensive care unit admission to the development of infection, presence of CRGNB colonization at admission, transfer from other hospitals, previous antibiotic use, enteral nutrition, transfusion, hemodialysis, mechanical ventilation, tracheostomy, reintubation, central venous catheter, arterial catheterization, chest tube, total parenteral nutrition, nasogastric tube use, and bronchoscopy procedures were significantly associated with CRGNB infections (P <0.05). Multivariate analysis identified the total length of stay in the hospital (odds ratio [OR]=1.02; 95% confidence interval [CI]: 1.01 to 1.03; P=0.001), colonization (OR=2.19; 95% CI: 1.53 to 3.13; P=0.001), previous antibiotic use (OR=2.36; 95% CI: 1.53 to 3.62; P=0.001), intubation (OR=1.59; 95% CI: 1.14 to 2.20; P=0.006), tracheostomy (OR=1.42; 95% CI: 1.01 to 1.99; P=0.047), and central venous catheter use (OR=1.62; 95% CI: 1.20 to 2.19; P=0.002) as the most important risk factors for CRGNB infection.

Conclusions

Colonization, previous use of antibiotics, and invasive interventions were recognized as the most important risk factors for infections. Future research should focus on measures for the control of these parameters.

Clinical characteristics and risk factors for neonatal bloodstream infection due to carbapenem-resistant Enterobacteriaceae: A single-centre Chinese retrospective study

OBJECTIVES

To analyse the clinical characteristics and risk factors for bloodstream infections (BSIs) caused by carbapenem-resistant Enterobacteriaceae (CRE) in neonates.

METHODS

This single-centre, retrospective study included all patients with BSIs admitted to a neonatal intensive care unit between 1 January 2015 and 30 April 2022. The clinical and microbiological data of patients were collected; predictors of 30-day mortality in patients with CRE BSIs were also identified in this study.

RESULTS

Among the 224 neonates with Enterobacteriaceae BSIs, 39.29% (88/224) of the patients developed CRE BSIs. The 30-day mortality rate reached up to 21.59% (19/88). The Quick Sequential Organ Failure Assessment score > 2 (odds ratio [OR] and 95% credibility interval [CI]: 3.852 [1.111-13.356], P < 0.05), prior to more than two kinds of antibiotics use (OR and 95% CI: 9.433 [1.562-56.973], P < 0.05), pneumonia (OR and 95% CI: 3.847 [1.133-13.061], P < 0.05), and caesarean section (OR and 95% CI: 2.678 [1.225-5.857], P < 0.05) were independent risk factors associated with CRE BSIs. Moreover, the risk factors for mortality in neonates with CRE BSIs were significantly associated with neonatal Sequential Organ Failure Assessment score > 6 (OR and 95% CI: 16.335 [1.446-184.517], P < 0.05).

CONCLUSION

Prior to more than two kinds of antibiotics use, Quick Sequential Organ Failure Assessment score > 2, pneumonia and caesarean section were independent risk factors for CRE BSIs. The Neonatal Sequential Organ Failure Assessment score > 6 was a risk factor for mortality associated with CRE BSIs.

Risk Factors and Predictive Nomogram for Carbapenem-Resistant Klebsiella pneumoniae in Children in a Grade 3 First-Class General Hospital in Central China

Background

This study determined risk factors for Carbapenem-resistant Klebsiella pneumoniae (CRKP)in children admitted to a grade 3 first-class general hospital and developed an individualized line graph predictive model.

Methods

The clinical data of 185 children infected with Klebsiella pneumoniae from January 2015 to December 2019 were analyzed retrospectively. Patients were grouped according to carbapenem resistance: CRKP group (50 cases) and CSKP (carbapenem-sensitive Klebsiella pneumoniae) group (135 cases). Risk factors for CRKP in children were screened by logistic regression analysis. The predictive model was established using R software and validated using the Bootstrap method.

Results

Age (odds ratio [OR]=0.104, 95% confidence interval [CI]: 0.026-0.408), intensive care unit admission (OR =2.829, 95% CI: 1.138-7.030), mechanical ventilation (OR =7.510, 95% CI: 3.140-17.961), surgery history (OR =5.005, 95% CI: 1.507-16.618) and glucocorticoid (OR =0.235, 95% CI: 0.099-0.557) were independent risk factors for CRKP in children (P < 0.05), The total risk score of each factor was 362.5, and the risk rate was 0.1-0.9. In receiver-operating characteristic curve analysis, the area under the curve of CRKP predicted by the total risk score was 0.872 (95% CI=0.844-0.901; P < 0.001). The correction curve indicated that the consistency between the observed value and the predicted value was good.

Discussion and Conclusion

This study successfully established a model based on the risk factors, with high accuracy and good predictive value for CRKP in children. Hospitals should take necessary preventive measures against the risk factors for drug-resistant bacteria, such as optimizing the configuration of ICU space, timely isolation of infected children, and adequate disinfection of ICU equipment. Which may reduce CRKP infection rate.

Analysis of Risk Factors for Carbapenem Resistant Klebsiella pneumoniae Infection and Construction of Nomogram Model: A Large Case-Control and Cohort Study from Shanxi, China

Background

Healthcare-associated infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) are now a global public health problem, increasing the burden of disease and public healthcare expenditures in various countries. The aim of this study was to analyse the risk factors for CRKP infections and to develop nomogram models to help clinicians predict CRKP infections at an early stage to facilitate diagnosis and treatment.

Methods

The clinical data of patients with Klebsiella pneumoniae (KP) infections in our hospital from January 2018 to January 2023 were collected. 174 patients with CRKP infections and 219 patients with CSKP infections were selected for case-control study. 27 predictors related to CRKP infections were determined. The least absolute shrinkage and selection operator (Lasso) regression was used to screen the characteristic variables, Multivariate logistic regression analysis was performed on the selected variables and a nomogram model was established. The discrimination and calibration of the nomogram model were evaluated by receiver operator curves (ROC) and calibration curves.

Results

Six predictive factors of ICU stay, fever time, central venous catheterization time, catheter indwelling time, carbapenem use and tetracycline use screened by lasso regression were included in the logistic regression model, and the nomogram was drawn to visualize the results. The area under ROC curve of training set and validation set was 0.894 (95% CI: 0.857, 0.931) and 0.872 (95% CI: 0.805, 0.939); The results of decision curve analysis also show that the model has good prediction accuracy.

Conclusion

This study established a nomogram to predict CRKP infection based on lasso-logistic regression model, which has certain guiding significance for early diagnosis of CRKP infections.

Carbapenem-Resistant Klebsiella pneumoniae Infection and Its Risk Factors in Older Adult Patients

Introduction

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection has recently gained worldwide interest due to limited treatment options and high morbidity and mortality rates. The aim of this study was to determine the risk factors of carbapenem-resistant K. pneumoniae (CRKP) infection in older adult patients.

Material and Methods

This retrospective, single-center study included 132 patients with healthcare-associated CRKP infection (case group) and 150 patients with healthcare-associated carbapenem-susceptible K. pneumoniae (CSKP) infection (control group), aged > 65 years.

Results

In the CRKP and CSKP groups, 79 (59.8%) and 80 (53.3%) patients were males, and the mean ages were 77.8 ± 7.8 and 76.6 ± 7.7 years, respectively. Diabetes mellitus (DM), malignancy, cardiovascular diseases (CVDs), surgical intervention, invasive mechanical ventilation, central venous catheter insertion, parenteral nutrition, hospitalization in the previous 6 months, antibiotic use in the previous 3 months, and exposure to cephalosporins, fluoroquinolones, and carbapenems were significantly more common in the CRKP than the CSKP group (all p < 0.05). The multivariate logistic regression analysis identified malignancy, CVDs, DM, invasive mechanical ventilation, hospitalization in the previous 6 months, ICU admission, and exposure to cephalosporins, quinolones, and carbapenems as independent risk factors for CRKP infection in older adult patients.

Conclusion

DM, malignancy, CVDs, ICU admission, invasive mechanical ventilation, and exposure to ceftriaxone, fluoroquinolones, and carbapenems were independent risk factors for CRKP infection in older adult patients. The identification of risk factors for CRKP infection can help to prevent and treat CRKP infection.

Risk factors and mortality of carbapenem-resistant Klebsiella pneumoniae bloodstream infection in a tertiary-care hospital in China: an eight-year retrospective study

BACKGROUND

The prevalence of carbapenem-resistant Klebsiella pneumoniae bloodstream infection (CRKP-BSI) is increasing worldwide. CRKP-BSI is associated with high rates of morbidity and mortality due to limited antibiotic choices. Here, we aim to identify the prevalence and risk factors for infection and mortality of CRKP BSI.

METHODS

This was a retrospective study of the past data from January 1st, 2012 to December 31st, 2019 of adult patients with KP-BSI in Xiangya Hospital, China.

RESULTS

Among the 706 incidences included in this study, 27.4% of them (212/753) being CR-KP strains. The occurrence of CRKP-BSI was increased from 20.69 to 37.40% from 2012 to 2019. Hematologic malignancies and ICU acquired infection were identified to be substantial risk factors of carbapenem resistance. The overall 28-day mortality rates of CRKP-BSI patients was significantly higher than that of CSKP-BSI (P < 0.001). Logistic regression analysis identified severe sepsis or septic shock incidents, inadequate empirical antimicrobial therapy and corticosteroids use preceding infection onset as the independent predictors of 28-day mortality of CRKP-BSI patients. However, high dose carbapenem combination therapy was identified as anticipated factors of low 28-day mortality.

CONCLUSION

The occurrence of CRKP-BSI was significantly increased during the study period. Hematologic malignancies and ICU acquired infection were associated with the development of CRKP BSI. Severe sepsis or septic shock incidents, inadequate empirical antimicrobial therapy and corticosteroids use preceding infection onset caused significant increase of mortality rates in CRKP-BSI patients. High dose carbapenem combination therapy was associated with better outcome.

Molecular Epidemiology, Clinical Characteristics and Risk Factors for Bloodstream Infection of Multidrug-Resistant Klebsiella pneumoniae Infections in Pediatric Patients from Tianjin, China

PURPOSE

The data on pediatrics with Multidrug-Resistant (MDR) Klebsiella pneumoniae infections are scarce. This study aims to investigate the molecular epidemiology of MDR Klebsiella pneumoniae, detect the mechanism of drug resistance, and determine the clinical risk factors for carbapenem-resistant Klebsiella pneumonia (CRKP) bloodstream infections (BSIs) in a children's hospital.

METHODS

A total of 62 strains were collected from Tianjin Children's Hospital. Carba NP and polymerase chain reactions (PCR) were performed to detect MDR mechanisms. Multilocus sequence typing (MLST) was used for analyzing strain homology. Clinical data were collected and logistic regression was used for BSI risk factors.

RESULTS

ST11 was the principal ST among the CRKP isolates clinically, accounting for 56.45% (35/62); there were also 57.14% (20/35) ST11 CRKP strains co-carrying bla NDM-5 and bla KPC-2, which were resistant to most of the tested antibiotics, being susceptible only to cotrimoxazole and tigecycline. The clinical data showed that 72.73% (40/55) of children with CRKP infection had serious underlying diseases; 20.00% (11/55) patients developed BSIs with the potential to cause multiple organ failure, shock and death. The logistic regression showed that the risk of BSIs caused by CRKP strain infections in children with hematological malignancies after chemotherapy was 7 times that of other children (95%Cl: 1.298-45.415, P=0.025).

CONCLUSION

ST11 was the prevalent clone in our hospital. The emergence of ST11 CRKP co-carrying bla NDM-5 and bla KPC-2 should be a cause for alarm as they were resistant to most of the tested antibiotics. CRKP strain infections are mainly occurring in young immunocompromised patients and the chemotherapy for hematological malignancies is an independent risk factor for BSIs.

Emergence of a NDM-1-producing ST25 Klebsiella pneumoniae strain causing neonatal sepsis in China

Carbapenem-resistant Klebsiella pneumoniae (CRKP) seriously threaten the efficacy of modern medicine with a high associated mortality rate and unprecedented transmission rate. In this study, we isolated a clinical K. pneumoniae strain DY1928 harboring bla_NDM-1 from a neonate with blood infection. Antimicrobial susceptibility testing indicated that DY1928 was resistant to various antimicrobial agents, including meropenem, imipenem, ceftriaxone, cefotaxime, ceftazidime, cefepime, piperacillin-tazobactam, and amoxicillin-clavulanate. S1 nuclease-pulsed field gel electrophoresis (S1-PFGE), southern blot and conjugation experiment revealed that the bla_NDM-1 gene was located on a conjugative plasmid of IncA/C2 type with a 147.9 kb length. Whole-genome sequencing showed that there was a conservative structure sequence (bla_NDM-1-ble-trpF-dsbD) located downstream of the bla_NDM-1 gene. Multilocus sequence typing (MLST) classified DY1928 as ST25, which was a hypervirulent K. pneumoniae type. Phylogenetic analysis of genomic data from all ST25 K. pneumoniae strains available in the NCBI database suggested that all bla_NDM-1 positive strains were isolated in China and had clinical origins. A mouse bloodstream infection model was constructed to test the virulence of DY1928, and 11 K. pneumoniae strains homologous to DY1928 were isolated from the feces of infected mice. Moreover, we found that DY1928 had a tendency to flow from the blood into the intestine in mice and caused multiple organ damage. To our knowledge, this is the first study to report an infection caused by bla_NDM-1-positive ST25 K. pneumoniae in the neonatal unit. Our findings indicated that stricter surveillance and more effective actions were needed to reduce the risk of disseminating such K. pneumoniae strains in clinical settings, especially in neonatal wards.

The Risk Factors of Carbapenem-Resistant Klebsiella pneumoniae Infection: A Single-Center Chinese Retrospective Study

Objective

The present study aims to explore potential infection and death risk factors in patients infected with carbapenem-resistant Klebsiella pneumoniae (CRKP).

Methods

A retrospective case-control study was performed at Beijing Shijitan Hospital, China. The clinical and microbiological data of patients infected with K. pneumoniae (K.pn) were collected; the clinical characteristics of patients infected with carbapenem-susceptible K.pn and CRKP were analyzed using logistic regression analysis.

Results

CRKP infection was significantly associated with prior carbapenem use (odds ratio [OR] and 95% credibility interval [CI]: 5.161 [1.840-32.233], P < 0.001), the use of more than three types of antibiotics for seven or more days (OR and 95% CI: 9.681 [2.662-18.122], P < 0.001), tracheotomy (OR and 95% CI: 5.015 [2.343-11.724], P < 0.001), and intensive care unit (ICU) stay (OR and 95% CI: 6.322 [2.02-12.231], P < 0.001). The risk of death in patients with CRKP infection was significantly associated with older age (OR and 95% CI of 70-80 years: 8.894 [1.972-67.346], P < 0.001; ≥80 years: 15.234 [2.072-93.452], P < 0.001), renal dysfunction (OR and 95% CI: 1.672 [1.104-7.451], P = 0.016), tracheotomy (OR and 95% CI: 2.051 [1.217-11.235], P = 0.002), and ICU stay (OR and 95% CI: 3.043 [2.174-18.453], P < 0.001).

Conclusion

Prior to carbapenem use, older age, renal dysfunction, tracheotomy, and ICU stay were independent risk factors for death in patients infected with CRKP.

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.

Impact of carbapenem resistance on mortality in patients infected with Enterobacteriaceae: a systematic review and meta-analysis

OBJECTIVES

To provide a comprehensive assessment of the impact of carbapenem resistance on mortality among patients infected with Enterobacteriaceae and to explore the source of heterogeneity across studies.

DESIGN

This systematic review was conducted following the guidelines of Cochrane Guidance and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

DATA SOURCES

We conducted a systematic literature search of the PubMed, Embase, Web of Science and Cochrane Library databases to identify relevant studies published between 1 January 1994 and 30 August 2020.

ELIGIBILITY CRITERIA

We included primary observational studies published in English that reported the mortality outcomes for hospitalised patients with confirmed infections due to carbapenem-resistant Enterobacteriaceae (CRE) and carbapenem-susceptible Enterobacteriaceae (CSE). Studies with no comparison group or with a comparison group of patients infected with unconfirmed CSE were excluded.

DATA EXTRACTION AND SYNTHESIS

Data extraction and assessment of risk bias were conducted independently by two reviewers. The pooled relative risk and risk difference were calculated as effect measures with 95% CIs using a random effects model. The heterogeneity across studies was assessed by Q-statistic and I² measures.

RESULTS

Of 10 304 studies initially identified, 50 studies were included in the meta-analyses. The results of the meta-analyses showed that carbapenem resistance has a significant positive effect on the probability of death for patients infected with Enterobacteriaceae for any type of mortality outcome. The results of the stratified analysis and meta-regression suggested that the effect of carbapenem resistance on the risk of death varied by infection type, sample size and year of publication.

CONCLUSIONS

Our results suggested that patients with CRE infection still face a greater risk of death than patients with CSE infection do, and an urgent need to develop new antibiotics and appropriate treatments to reduce the risk of death.

PROSPERO REGISTRATION NUMBER

CRD42020176808.

Molecular Epidemiology and Drug Resistant Mechanism of Carbapenem-Resistant Klebsiella pneumoniae in Elderly Patients With Lower Respiratory Tract Infection

Infection by carbapenem-resistant Klebsiella pneumoniae (CRKp) hampers the treatment of elderly patients with lower respiratory tract infection (LRTI); however, relevant data with respect to the characteristics of CRKp in elderly patients with LRTIs are limited. In the present study, K. pneumoniae isolated from elderly patients with LRTIs was collected and identified by VITEK-MS. VITEK 2 compact was used for drug sensitivity test to screen CRKps, and broth dilution method was used for drug sensitivity of tigecycline and colistin. The resistance genes, virulence genes, and serotypes of CRKps were detected via polymerase chain reaction. The homology of CRKps was analyzed via PFGE and MLST. Moreover, plasmid conjugation experiment was carried out to determine the transferability of carbapenem resistance. PCR-based replicon typing (PBRT) and S1 nuclease-PFGE were conducted for plasmid profiling. From January 2019 to August 2019, 258 elderly patients with LRTIs caused by K. pneumoniae were observed; of these, 31 (12.02%) infections were caused by CRKp strains. Majority of the patients were admitted to the intensive care unit and neurosurgery wards. Intracranial hemorrhage and pneumonia were the most common underlying diseases. Furthermore, 29 patients infected by CRKp had been exposed to various antimicrobial drugs before the positive culture. All isolates exhibited high resistance to β-lactam antibiotics. The predominant carbapenem resistance gene was bla_KPC−2, and CRKps carrying bla_KPC−2 were all ST11 type. Two bla_NDM−5 carrying isolates were assigned to ST307 and ST1562, respectively. Conjugative assays revealed that plasmids harboring bla_NDM−5 gene were self-transmissible. Plasmid analysis suggested that two bla_NDM−5 were located on a ~45 kb IncX3 type plasmid. The high incidence of CRKp in elderly patients with LRTIs indicates the urgent need for further surveillance and strict infection control measures.

Real-world use of ceftolozane/tazobactam: a systematic literature review

Background

Antibacterial-resistant gram-negative infections are a serious risk to global public health. Resistant Enterobacterales and Pseudomonas aeruginosa are highly prevalent, particularly in healthcare settings, and there are limited effective treatment options. Patients with infections caused by resistant pathogens have considerably worse outcomes, and incur significantly higher costs, relative to patients with susceptible infections. Ceftolozane/tazobactam (C/T) has established efficacy in clinical trials. This review aimed to collate data on C/T use in clinical practice.

Methods

This systematic literature review searched online biomedical databases for real-world studies of C/T for gram-negative infections up to June 2020. Relevant study, patient, and treatment characteristics, microbiology, and efficacy outcomes were captured.

Results

There were 83 studies comprising 3,701 patients were identified. The most common infections were respiratory infections (52.9% of reported infections), urinary tract infections (UTIs; 14.9%), and intra-abdominal infections (IAIs; 10.1%). Most patients included were seriously ill and had multiple comorbidities. The majority of patients had infections caused by P.aeruginosa (90.7%), of which 86.0% were antimicrobial-resistant. C/T was used as both a 1.5 g q8h and 3 g q8h dose, for a median duration of 7–56 days (varying between studies). Outcome rates were comparable between studies: clinical success rates ranged from 45.7 to 100.0%, with 27 studies (69%) reporting clinical success rates of > 70%; microbiological success rates ranged from 31 to 100%, with 14 studies (74%) reporting microbiological success rates of > 70%. Mortality rates ranged from 0 to 50%, with 31 studies (69%) reporting mortality rates of ≤ 20%. In comparative studies, C/T was as effective as aminoglycoside- or polymyxin-based regimens, and in some instances, significantly more effective.

Conclusions

The studies identified in this review demonstrate that C/T is effective in clinical practice, despite the diverse group of seriously ill patients, different levels of resistance of the pathogens treated, and varying dosing regimens used. Furthermore, comparative studies suggest that C/T offers a successful alternative to standard of care (SoC).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-021-00933-8.

Does Fluoroquinolones and Third-Generation Cephalosporins Restriction Reverse Extended-Spectrum β-Lactamases Klebsiella pneumoniae Resistance Rates?

Aim: To decrease the incidence and resistance rates of extended-spectrum β-lactamases (ESBL) Klebsiella pneumoniae (KP) by restriction of the use of third-generation cephalosporins (3GCs) and fluoroquinolones. Methods: Consumption of 3GCs, fluoroquinolones, and carbapenems in association with ertapenem and fluoroquinolone-resistant KP isolates, were analyzed in 21 months by autoregressive integrated moving average models. A follow-up analysis was performed 5 years later. Results: Consumption of 3GCs decreased significantly during the postintervention period. Their restriction was associated with a decrease in ertapenem-resistant KP isolates by 17.5%. Fluoroquinolone, 3GCs, and carbapenem use did not significantly predict the percentage of ertapenem-resistant KP isolates. Fluoroquinolone, but not cephalosporin use, significantly predicted the percentage of fluoroquinolone-resistant isolates, with an increase of 1 defined daily dose (DDD) of fluoroquinolone/100 occupied bed-days (OBDs) corresponding to a 0.32% increase of fluoroquinolone-resistant isolates (p = 0.008). A decrease of 1 DDD of carbapenem/100 OBD was associated with a 16.94% increase of fluoroquinolone-resistant isolates (p = 0.007). Five years later, the consumption of all three antimicrobial classes increased significantly compared with the 2011-2013 period, whereas ertapenem-resistant KP rates significantly decreased. Conclusion: This study may bring a valuable contribution to the understanding of the intricate association between antibiotic consumption and bacterial resistance. Reporting a spectrum of different results could present a useful basis for more profound research of various interventions' effects.

Resistance Trends of Klebsiella pneumoniae Causing Urinary Tract Infections in Chongqing, 2011-2019

Purpose

To analyze the characteristics and trends of drug resistance for Klebsiella pneumoniae (K. pneumoniae), isolated from urinary tract infections (UTIs), to common antibiotics used in clinics.

Methods

This retrospective study was conducted in a teaching hospital in Chongqing from 2011 to 2019. Laboratory data of isolated bacteria were collected and analyzed.

Results

Among the 17,966 non-repetitive strains isolated from the urine sample, a total of 1543 K. pneumoniae isolates were identified, with an isolation frequency secondary only to Escherichia coli (E. coli) and there was a peak in the K. pneumoniae isolates in the year 2013. During the period, the rate of extended-spectrum β-lactamase (ESBL)-producing K. pneumoniae fell from 48.4% in 2011 to 32.9% in 2019, and a marked jump of resistance was seen in carbapenems from 2.2% to 18.0%. The peak of carbapenem resistance rate (22.6%) to K. pneumoniae was observed in 2017 along with a low ESBL-producing rate (30.9%). Piperacillin/tazobactam and cefepime resistance levels went up from 4.4% to 25.7% and from 18.2% to 30.5%, respectively. Moreover, the K. pneumoniae isolates resistance rate to carbapenems and amikacin gradually grew up, showing their peaks in 2017, and then dropped year by year. However, ceftazidime and aztreonam resistance levels were relatively stable, fluctuating between 21.8% and 35.6%, 32.2% and 39.4%, respectively.

Conclusion

There is a significant upward tendency in carbapenem resistance rate and a downward tendency in ESBL-production rate in K. pneumoniae isolates from UTIs, and continuous surveillance is necessary in the future.

Risk factors for carbapenem-resistant Gram-negative bacterial infections: a systematic review

BACKGROUND

Rapid and widespread increases in carbapenem resistance (CR) necessitate identification of risk factors to guide appropriate interventions.

OBJECTIVES

We aimed to identify risk factors for CR Gram-negative infection through a systematic literature review.

DATA SOURCES

We searched MEDLINE (via OvidSP and PubMed) and Embase (via OvidSP) databases and the Cochrane Central Register of Controlled Trials.

STUDY ELIGIBILITY CRITERIA

Prospective or retrospective cohort and case-control studies reporting quantitative data on risk factors associated with infections due to CR Gram-negative pathogens in hospitalized patients were eligible.

PARTICIPANTS

Studies included hospitalized patients with CR infection caused by Gram-negative bacterial pathogens (Enterobacterales and non-fermenters).

METHODS

Searches were conducted in January 2018/December 2019 to identify studies published since 2007. Risk factor data were extracted and grouped by factor. The primary metric was proportion of studies reporting a significant association with CR infection for each factor.

RESULTS

In total, 92 studies were identified. Risk factors most frequently reported as significantly associated with CR infection (>10 studies) were previous antibiotic use (91.1%; 72/79 studies); previous carbapenem use (82.6%; 57/69); previous colonization (72.7%; 8/11); mechanical ventilation (66.7%; 36/54); previous intensive care unit stay (64.4%; 38/59); dialysis (61.1%; 11/18); catheter (58.0%; 40/69); length of stay in hospital (54.5%; 30/55); comorbidities (52.7%; 39/74); APACHE II (51.7%; 15/29); and intubation (51.4%; 18/35). Risk factors were mostly consistent across different species and sites of infection.

CONCLUSIONS

Several variables, particularly previous antibiotic use, are strong risk factors for CR infection. Interventions to mitigate against CR infection should target these factors.

Innate Immune Effectors Play Essential Roles in Acute Respiratory Infection Caused by Klebsiella pneumoniae

Innate immune effectors constitute the first line of host defense against pathogens. However, the roles of these effectors are not clearly defined during Klebsiella pneumoniae (K. pneumoniae) respiratory infection. In the current study, we established an acute pneumonia model of K. pneumoniae respiratory infection in mice and confirmed that the injury was most severe 48 h post infection. Flow cytometric assay demonstrated that alveolar macrophages were the predominant cells in BALF before infection, and neutrophils were quickly recruited after infection, and this was in consistent with the kinetics of chemokine expression. Further, we depleted neutrophils, macrophages, and complement pathways in vivo and challenged these mice with a sublethal dose of K. pneumonia, the result showed that 80%, 60%, and 40% of mice were died in these groups, respectively, while no deaths occurred in the control group. Besides, innate immune effector depleted mice showed higher bacterial burdens in lungs and blood, companied with more severe lung damage and increased levels of cytokine/chemokine expression. These results demonstrated that the innate immune effectors are critical in the early controlling of K. pneumoniae infection, and neutrophils are the most important. Thus, alternative strategies targeting these innate immune effectors may be effective in controlling of K. pneumoniae respiratory infection.

Predictive factors for sepsis by carbapenem resistant Gram-negative bacilli in adult critical patients in Rio de Janeiro: a case-case-control design in a prospective cohort study

Background

Studies have investigated risk factors for infections by specific species of carbapenem-resistant Gram-negative bacilli (CR-GNB), but few considered the group of GNB species and most of them were performed in the setting of bacteremia or hospital infection. This study was implemented to identify risk factors for sepsis by CR- and carbapenem-susceptible (CS) GNB in intensive care unit (ICU) patients to improve management strategies for CR-GNB sepsis.

Methods

We developed a case-case-control study from a prospective cohort of patients with systemic inflammatory response syndrome (SIRS), sepsis-2 or sepsis-3 criteria in which blood and other sample cultures were collected and antimicrobial therapy was instituted, in an adult clinical-surgical ICU, at tertiary public hospital in Rio de Janeiro, from August 2015 through March 2017.

Results

Among the total of 629 ICU admissions followed by 7797 patient-days, after applying inclusion and exclusion criteria we identified 184 patients who developed recurrent or single hospital-acquired sepsis. More than 90% of all evaluable cases of sepsis and 87% of control group fulfilled the modified sepsis-3 definition. Non-fermenting bacilli and ventilator-associated pneumonia predominated as etiology and source of CR-GNB sepsis. While Enterobacteriaceae and intra-abdominal surgical site plus urinary-tract infections prevailed in CS-GNB than CR-GNB sepsis. Carbapenemase production was estimated in 76% of CR-GNB isolates. Multivariate logistic regression analysis revealed previous infection (mostly hospital-acquired bacterial infection or sepsis) (OR = 4.28; 95% CI 1.77–10.35), mechanical ventilation (OR = 4.21; 95% CI 1.17–15.18), carbapenem use (OR = 3.42; 95% CI 1.37–8.52) and length of hospital stay (OR = 1.03; 95% CI 1.01–1.05) as independent risk factors for sepsis by CR-GNB. While ICU readmission (OR = 6.92; 95% CI 1.72–27.78) and nosocomial diarrhea (OR = 5.32; 95% CI 1.07–26.45) were factors associated with CS-GNB sepsis.

Conclusions

The investigation of recurrent and not only bacteremic episodes of sepsis was the differential of this study. The results are in agreement with the basic information in the literature. This may help improve management strategies and future studies on sepsis by CR-GNB.

Risk Factors for Carbapenem-Resistant Klebsiella pneumoniae Bloodstream Infections and Outcomes

Purpose

The incidence of carbapenem-resistant Klebsiella pneumoniae (CRKP) bloodstream infections (BSIs) is increasing globally; however, little has been reported on the risk factors and outcomes of CRKP BSIs in central China. This study aimed to determine the clinical risk factors for CRKP BSIs and the outcomes of CRKP BSIs.

Patients and Methods

We performed a case-control study of 239 patients with K. pneumoniae BSIs who were treated at Henan Provincial People’s Hospital between July 2017 and July 2018. The cases (n=98, 41%) had CRKP BSIs, and the controls (n=141, 59%) had non-carbapenem-resistant K. pneumoniae (non-CRKP) BSIs. Antimicrobial sensitivity was determined using automated broth microdilution and an agar disk diffusion method. Data were obtained from clinical and laboratory records. Multivariate logistic regression and Pearson chi-square tests were used to identify clinical factors and outcomes associated with carbapenem resistance.

Results

Risk factors for carbapenem resistance included recent carbapenem use (odds ratio [OR]: 9.98, 95% confidence interval [CI]: 5.2–17.1, P<0.001), invasive procedures (OR: 11.1, 95% CI: 3.3–37.7, P<0.001), and pre-existing diseases of the digestive system (OR: 8.22, 95% CI: 1.73–39.2, P=0.008). Treatment failure was more frequent in the cases (84.7%) than in the controls (32.6%).

Conclusion

Exposure to antibiotics, especially carbapenems, and invasive procedures were the major risk factors for carbapenem resistance among patients with K. pneumoniae BSIs. Strict control measures should be implemented to prevent the emergence and spread of CRKP.

Risk factors for carbapenem-resistant Klebsiella pneumoniae infection relative to two types of control patients: a systematic review and meta-analysis

Background

Studies on risk factors for carbapenem-resistant Klebsiella pneumoniae (CRKP) infection have provided inconsistent results, partly due to the choice of the control group. We conducted a systematic review and meta-analysis to assess the risk factors for CRKP infection by comparing CRKP-infected patients with two types of controls: patients infected with carbapenem-susceptible Klebsiella pneumoniae (comparison 1) or patients not infected with CRKP (comparison 2).

Methods

Data on potentially relevant risk factors for CRKP infection were extracted from studies indexed in PubMed, EMBASE, Web of Science or EBSCO databases from January 1996 to April 2019, and meta-analyzed based on the outcomes for each type of comparison.

Results

The meta-analysis included 18 studies for comparison 1 and 14 studies for comparison 2. The following eight risk factors were common to both comparisons: admission to intensive care unit (ICU; odds ratio, OR_{comparison 1} = 3.20, OR_{comparison 2} = 4.44), central venous catheter use (2.62, 3.85), mechanical ventilation (2.70, 4.78), tracheostomy (2.11, 8.48), urinary catheter use (1.99, 0.27), prior use of antibiotic (6.07, 1.61), exposure to carbapenems (4.16, 3.84) and exposure to aminoglycosides (1.85, 1.80). Another 10 risk factors were unique to comparison 1: longer length of hospital stay (OR = 15.28); prior hospitalization (within the previous 6 months) (OR = 1.91); renal dysfunction (OR = 2.17); neurological disorders (OR = 1.52); nasogastric tube use (OR = 2.62); dialysis (OR = 3.56); and exposure to quinolones (OR = 2.11), fluoroquinolones (OR = 2.03), glycopeptides (OR = 3.70) and vancomycin (OR = 2.82).

Conclusions

Eighteen factors may increase the risk of carbapenem resistance in K. pneumoniae infection; eight factors may be associated with both K. pneumoniae infections in general and CRKP in particular. The eight shared factors are likely to be ‘true’ risk factors for CRKP infection. Evaluation of risk factors in different situations may be helpful for empirical treatment and prevention of CRKP infections.

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.

Risk factors of health care-associated infection in elderly patients: a retrospective cohort study performed at a tertiary hospital in China

Background

The elderly inpatients are in high risk of suffering health-care associated infection (HAI). The study aimed to analyze the risk factors of health-care associated infection (HAI) in elderly hospitalized patients to prevent it and improve the recovery rate of elderly patients.

Methods

The study was a Retrospective Cohort Study based on a 3-year surveillance in elderly inpatients in a large tertiary hospital in China. A retrospective review of the elderly inpatients ≥60 years with or without HAI were conducted. Binary multivariable logistic regression was used to evaluate the potential association between HAI and risk factors.

Results

We investigated a total of 60,332 subjects aged 60 years old or above. The incidence of HAI in elderly was 2.62%. With adjustment for some factors, advanced age, hospital days before HAI, intensive care unit (ICU) admission, use of ventilator, central line catheter or urinary catheter and cerebral hemorrhage, cerebral infarction, brain neoplasms, diabetes mellitus, coronary artery disease, malignant tumor and malignant hematonosis had significantly increased odds ratios (OR) of suffering from HAI compared with the control group but body weight and operation decreased OR.

Conclusion

Our findings suggested that advanced age, accompanied by some neurological and chronic noncommunicable diseases, hospital days before HAI, ICU admission, and use of devices were risk factors of suffering HAI in the elderly but the body weight and operation were the potential protective factors in this sample.

Risk Factors for Carbapenem-resistant Klebsiella pneumoniae Infection and Mortality of Klebsiella pneumoniae Infection

Background:

Klebsiella pneumoniae (KP) is a pathogen commonly causing nosocomial infection. Carbapenem-resistant KP (CRKP) is more resistant to multiple antimicrobial drugs than carbapenem-susceptible KP (CSKP) isolates. The aim of the present study was to identify the risk factors for CRKP infection and the predictors of mortality among KP-infected adult patients.

Methods:

Patients with CRKP and CSKP infection were categorized as the case group and control group, respectively, and we conducted a 1:1 ratio case-control study on these groups. The CRKP isolates collected were tested for antimicrobial susceptibility and presence of KP carbapenemase (KPC) gene. Clinical data were collected to identify risk factors for CRKP infection and mortality of KP infection. Risk factors were analyzed under univariable and multivariable logistic regression model.

Results:

The independent risk factors for CRKP infection were admission to Intensive Care Unit (odds ratio [OR]: 15.486, 95% confidence interval [CI]: 3.175–75.541, P < 0.001); use of β-lactams and β-lactamase inhibitor combination (OR: 4.765, 95% CI: 1.508–15.055, P = 0.008); use of cephalosporins (OR: 8.033, 95% CI: 1.623–39.763, P = 0.011); fluoroquinolones (OR: 6.090, 95% CI: 1.343–27.613, P = 0.019); and indwelling of urethral catheter (OR: 6.164, 95% CI: 1.847–20.578, P = 0.003). However, older age (OR: 1.079, 95% CI: 1.005–1.158, P = 0.036), Charlson comorbidity index (OR: 4.690, 95% CI: 2.094–10.504, P = 0.000), and aminoglycoside use (OR: 670.252, 95% CI: 6.577–68,307.730, P = 0.006) were identified as independent risk factors for patient deaths with KP infection. The mortality of CRKP group was higher than that of the CSKP group. KPC gene did not play a role in the CRKP group. CRKP mortality was high.

Conclusion:

Implementation of infection control measures and protection of the immunefunction are crucial.

Effect of short-term carbapenem restriction on the incidence of non-pseudomonal multi-drug resistant Gram-negative bacilli in an intensive care unit

We conducted a two-phase retrospective study to investigate the impact of a short-term carbapenem restriction on the incidence of non-pseudomonal multidrug-resistant (MDR) Gram-negative bacilli in our intensive care unit (ICU). The first phase of the study (before carbapenem restriction) was conducted between May and July 2016, and the second phase (implementation of carbapenem restriction) between September and November 2016. The incidence of all non-pseudomonal MDR Gram-negative bacilli (extended-spectrum β-lactamase-producing Enterobacteriaceae, carbapenem-resistant Enterobacteriaceae and MDR Acinetobacter baumannii) decreased significantly after carbapenem restriction. Patients positive for non-pseudomonal MDR Gram-negative bacilli before and after carbapenem restriction were comparable in terms of age, weight, Acute Physiology and Chronic Health Evaluation IV score, central venous catheter placement, and vasopressor use. This report suggests that short-term carbapenem restriction for 3 months may be an effective strategy for reducing the incidence of non-pseudomonal MDR Gram-negative bacilli.

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.

Risk Factors for Carbapenem Resistant Klebsiella pneumoniae Hospital Infection in the Intensive Care Unit

Carbapenem-resistant Klebsiella pneumoniae (CR-Kp) has become a major threat to patients in hospitals, increasing mortality, length of stay and costs.

The aim of this study was to discover risk factors for the development of hospital infections (HIs) caused by CR-Kp.

A prospective cohort study was conducted in the Medical-Surgical Intensive Care Unit of the Clinical Centre in Kragujevac, Kragujevac, Serbia, from January 1, 2011, to December 31, 2015. The “cases” were patients with HIs caused by CR-Kp, while the “controls” were patients infected with carbapenem-sensitive Klebsiella pneumoniae (CS-Kp). The significance of multiple putative risk factors for HIs caused by CR-Kp was tested using multivariate logistic regression.

Although univariate analyses pointed to many risk factors, with a significant influence on the occurrence of hospital CR-Kp infections, the multivariate logistic regression identified five independent risk factors: use of mechanical ventilation (OR=6.090; 95% CI=1.030-36.020; p=0.046); length of antibiotic therapy before HIs (days) (OR=1.080; 95% CI=1.003-1.387; p=0.045); previous use of carbapenems (OR=7.005; 95% CI=1.054-46.572; p=0.044); previous use of ciprofloxacin (OR=20.628; 95% CI=2.292-185.687; p=0.007) and previous use of metronidazole (OR=40.320; 95% CI=2.347-692.795; p=0.011)

HIs caused by CR-Kp are strongly associated with the use of mechanical ventilation and the duration of the previous use of certain antibiotics (carbapenems, ciprofloxacin and metronidazole).

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.

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.

Clinical and economic impact of antibiotic resistance in developing countries: A systematic review and meta-analysis

INTRODUCTION

Despite evidence of the high prevalence of antibiotic resistant infections in developing countries, studies on the clinical and economic impact of antibiotic resistance (ABR) to inform interventions to contain its emergence and spread are limited. The aim of this study was to analyze the published literature on the clinical and economic implications of ABR in developing countries.

METHODS

A systematic search was carried out in Medline via PubMed and Web of Sciences and included studies published from January 01, 2000 to December 09, 2016. All papers were considered and a quality assessment was performed using the Newcastle-Ottawa quality assessment scale (NOS).

RESULTS

Of 27 033 papers identified, 40 studies met the strict inclusion and exclusion criteria and were finally included in the qualitative and quantitative analysis. Mortality was associated with resistant bacteria, and statistical significance was evident with an odds ratio (OR) 2.828 (95%CI, 2.231-3.584; p = 0.000). ESKAPE pathogens was associated with the highest risk of mortality and with high statistical significance (OR 3.217; 95%CIs; 2.395-4.321; p = 0.001). Eight studies showed that ABR, and especially antibiotic-resistant ESKAPE bacteria significantly increased health care costs.

CONCLUSION

ABR is associated with a high mortality risk and increased economic costs with ESKAPE pathogens implicated as the main cause of increased mortality. Patients with non-communicable disease co-morbidities were identified as high-risk populations.

Piperacillin-tazobactam as alternative to carbapenems for ICU patients

Several studies suggest that alternatives to carbapenems, and particulary beta-lactam/beta-lactamase inhibitor combinations, can be used for therapy of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE)-related infections in non-ICU patients. Little is known concerning ICU patients in whom achieving the desired plasmatic pharmacokinetic/pharmacodynamic (PK/PD) target may be difficult. Also, in vitro susceptibility to beta-lactamase inhibitors might not translate into clinical efficacy. We reviewed the recent clinical studies examining the use of BL/BLI as alternatives to carbapenems for therapy of bloodstream infection, PK/PD data and discuss potential ecological benefit from avoiding the use of carbapenems. With the lack of prospective randomized studies, treating ICU patients with ESBL-PE-related infections using piperacillin-tazobactam should be done with caution. Current data suggest that BL/BLI empirical use should be avoided for therapy of ESBL-PE-related infection. Also, definitive therapy should be reserved to patients in clinical stable condition, after microbial documentation and results of susceptibility tests. Optimization of administration and higher dosage should be used in order to reach pharmacological targets.

Factors associated with acquisition of carbapenem-resistant Enterobacteriaceae

Objective:

to identify possible risk factors for acquisition of Enterobacterial strains with a marker for resistance to carbapenems.

Methods:

exploratory case-control study performed in hospital settings. The study sample consisted of patients with biological specimens that tested positive for carbapenem-resistant Enterobacteriaceae (cases), with the disk diffusion test and Etest, and controls with biological samples testing negative for carbapenem-resistant Enterobacteriaceae. In all, 65 patients were included: 13 (20%) cases and 52 (80%) controls.

Results:

the microorganisms isolated were Serratia marcescens (6), Klebsiella pneumoniae (4), and Enterobacter cloacae (3). Univariate analysis revealed that length of hospitalization prior to sample collection (p=0.002) and having a surgical procedure (p=0.006) were statistically significant. In the multivariable logistic regression model, both were still significant, with odds ratios of 0.93 (p = 0.009; 95% CI: 0.89 to 0.98) for length of hospitalization prior to sample collection, and 9.28 (p = 0.05; 95% CI: 1.01 to 85.14) for having a surgical procedure.

Conclusion:

shorter hospitalization times and increased surveillance of patients undergoing surgery could play a decisive role in reducing the spread of carbapenem-resistant microorganisms in hospital settings.

Clinical and molecular characteristics, risk factors and outcomes of Carbapenem-resistant Klebsiella pneumoniae bloodstream infections in the intensive care unit

Background

To analyze the clinical characteristics and outcomes of carbapenem-resistant Klebsiella pneumoniae (CRKp) and carbapenem-susceptible K. pneumoniae (CSKp) bloodstream infections (BSIs), and to study the risk factors for development of CRKp BSI and K. pneumoniae BSI-related mortality.

Methods

A retrospective case control study of patients with K. pneumoniae BSI was conducted in the intensive care unit of the First Affiliated Hospital, Medical of College, Zhejiang University from January 2013 to December 2014. Carbapenem resistance was defined in accordance with the Clinical and Laboratory Standards Institute 2016 guidelines. Risk factors for the development of CRKp BSI and risk factors for mortality due to K. pneumoniae BSI were assessed. Virulence genes were detected by polymerase chain reaction assay.

Results

In total, 48 patients were enrolled in the study, including 31 (65%) patients with CRKp BSI and 17 (35%) patients with CSKp BSI. CSKp infection was associated with more severe clinical symptoms, particularly a higher serum creatinine level (165.06 ± 127.01 in the CSKp group vs. 93.77 ± 84.35 μmol/L in the CRKp group, p = 0.039), but there was no significant difference in prognosis between the CSKp and CRKp groups. On multivariate analysis, indwelling central venous catheter (p = 0.045) was the only factor independently associated with CRKp bacteremia. However, the mortality of K. pneumoniae BSI patients was not correlated with carbapenem resistance. In addition, the isolates had diverse clonality and different origins. The frequency of detection of the allS and magA virulence genes was higher in the CSKp group than in the CRKp group (alls p = 0.04; magA p = 0.047).

Conclusions

Patients in the CSKp group experienced more severe clinical symptoms, although mortality did not differ significantly between the CRKp and CSKp groups. An indwelling central venous catheter was the only factor independently associated with CRKp BSI. The mortality of patients with K. pneumoniae BSI was not associated with carbapenem resistance. The frequency of virulence genes was higher in the CSKp group than in the CRKp group.

Molecular characterization of intestinal carriage of carbapenem-resistant Enterobacteriaceae among inpatients at two Iranian university hospitals: first report of co-production of bla NDM-7 and bla OXA-48

Gastrointestinal colonization of carbapenem-resistant Enterobacteriaceae (CRE) could serve as a reservoir for the transmission of these pathogens in the clinical setting. The aim of this study was to investigate the intestinal carriage of CRE and to analyze risk factors for CRE carriage. Rectal swabs were collected from 95 patients at two Iranian university hospitals. CRE screening was performed using selective media (CHROMagar and MacConkey agar). Polymerase chain reaction (PCR) was used to detect carbapenemase-encoding genes. Clonal relatedness was investigated by pulsed-field gel electrophoresis (PFGE). The rate of carriage of CRE in hospitalized patients was 37.9%. Overall, 54 CRE isolates were identified, of which 47 were carbapenemase-producers. All of the 54 CRE were detected using CHROMagar compared with 52 CRE detected using MacConkey agar. Fifteen patients were colonized by multiple CRE isolates. Three significant risk factors for CRE carriage were detected: intensive care unit (ICU) hospitalization, antibiotic exposure, and mechanical ventilation. bla _OXA-48 was the most frequent carbapenemase detected, followed by bla _NDM-1 and bla _NDM-7. Eleven carbapenemase-producing Enterobacteriaceae (CPE) isolates co-harbored bla _NDM-1 and bla _OXA-48. Also, six CPE isolates co-harbored bla _NDM-7 and bla _OXA-48. We did not detect bla _KPC, bla _GES, bla _IMP, or bla _VIM. PFGE analysis showed that Escherichia coli clones were diverse, while Klebsiella pneumoniae isolates were divided into four clusters. Cluster I was the major clone carrying bla _OXA-48 and bla _CTX-M-15 genes. In our study, the carriage rate of CRE was high and the emergence of CPE isolates among patients is alarming. The implementation of adequate preventive measures such as active surveillance is urgently needed to control the spread of CPE in the healthcare setting.

Risk factors and clinical outcomes for carbapenem-resistant Gram-negative late-onset sepsis in a neonatal intensive care unit

BACKGROUND

Carbapenem-resistant (CR), Gram-negative (GN), late-onset sepsis (LOS) is a serious threat in the neonatal intensive care unit (NICU).

AIM

To assess the prevalence of CR-GN-LOS in NICU patients and to identify the risk factors and outcomes associated with its acquisition.

METHODS

Neonates with carbapenem-susceptible (CS)-GN-LOS were compared with those with CR-GN-LOS in a two-year observational study.

FINDINGS

A total of 158 patients had GN-LOS; 100 infants had CS-GN-LOS and 58 infants had CR-GN-LOS. The incidence rate of CR-GN-LOS was 6.5 cases per 1000 patient-days. The most frequent bacterial strain in both groups was Klebsiella pneumoniae. The duration of total parenteral nutrition (TPN) (P=0.006) and prior carbapenem use (P=0.01) were independent risk factors for CR-GN-LOS acquisition. CR-GN-LOS was associated with higher mortality than CS-GN-LOS (P=0.04). Birth weight, small for gestational age, time to start enteral feeding, exclusive formula feeding, previous surgery, previous antifungal use, central venous device before onset, duration of central venous device, and infectious complications were identified as dependent risk factors for overall mortality. However, only male gender (P=0.04) and infectious complications (P < 0.001) were independent risk factors associated with mortality. Infectious complication rates, duration of mechanical ventilation, and length of hospital stay were significantly higher in infants with CR compared to CS-GN-LOS.

CONCLUSION

The duration of TPN and carbapenem use were the independent predictors for CR-GN-LOS acquisition. CR-GN-LOS is associated with higher mortality, infectious complication rates, longer mechanical ventilation, and longer hospital stay. Male gender and infectious complications were the independent risk factors for mortality in neonates with GN-LOS.

Carbapenem-resistant Klebsiella pneumoniae in Barbados: Driving change in practice at the national level

Introduction

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is of growing concern globally. The risk for transmission of antimicrobial resistant organisms across several continents to the Caribbean is a real one given its tourism industry. After a cluster of cases of CRKP were detected, several studies detailed in this report were initiated to better characterize the problem.

Methods

A hospital-wide point prevalence study and active surveillance were performed at Queen Elizabeth Hospital (QEH) in Barbados in 2013 to assess the prevalence of CRKP infection/colonization. Following this, a 1-year longitudinal study measured the prevalence of CRKP isolates in the hospital and across all healthcare facilities in the country.

Results

In 2013, eleven viable isolates of CRKP from cluster of cases were sent for molecular epidemiology studies. When sequenced, they were found to be the ST-258 clone. Identification of a cluster of cases of CRKP ST-258/512 clones indicated person-to-person transmission. In September 2013, the hospital-wide point prevalence study revealed 18% of patients (53/299) at the hospital were either colonized or infected with CRKP. The infection to colonization ratio was 1:7. Patients who were infected/colonized vs. non-colonized were older (64.7 vs. 48.7 years, p<0.0001), were hospitalized longer (42.5 days vs. 27 days, p = 0.0042), were more likely to have an invasive device (66% vs. 32%, p<0.0001), especially urinary catheters (55% vs. 24%, p<0.0001), and were more likely to have used antimicrobials within the prior 14 days (91% vs. 46%, p<0.0001). Specific antimicrobials, including fluoroquinolones and piperacillin-tazobactam, were significantly associated with infection/colonization. In 2014, the 12-month period prevalence of CRKP in Barbados was 49.6 per 100,000 population and of blood stream infections was 3.2 per 100,000 population.

Conclusions

This point prevalence study identified patients at-risk of acquisition of CRKP and allowed QEH to implement interventions aimed at decreasing the prevalence of CRKP. Organization of a National and regional Infection Prevention and Control Committee in 2014 aimed to strengthen antimicrobial resistance surveillance programs across the English-speaking Caribbean were established.

Bioactive Molecule from Streptomyces sp. Mitigates MDR Klebsiella pneumoniae in Zebrafish Infection Model

The emergence and spread of multi-drug resistant (MDR) especially carbapenem-resistant Klebsiella pneumoniae is a major emerging threat to public health, leading to excess in mortality rate as high as 50-86%. MDR K. pneumoniae manifests all broad mechanisms of drug resistance, hence development of new drugs to treat MDR K. pneumoniae infection has become a more relevant question in the scientific community. In the present study a potential Streptomyces sp. ASK2 was isolated from rhizosphere soil of medicinal plant. The multistep HPLC purification identified the active principle exhibiting antagonistic activity against MDR K. pneumoniae. The purified compound was found to be an aromatic compound with aliphatic side chain molecule having a molecular weight of 444.43 Da. FT-IR showed the presence of OH and C=O as functional groups. The bioactive compound was further evaluated for drug induced toxicity and efficacy in adult zebrafish infection model. As this is the first study on K. pneumoniae - zebrafish model, the infectious doses to manifest sub-clinical and clinical infection were optimized. Furthermore, the virulence of K. pneumoniae in planktonic and biofilm state was studied in zebrafish. The MTT assay of ex vivo culture of zebrafish liver reveals non-toxic nature of the proposed ASK2 compound at an effective dose. Moreover, significant increase in survival rate of infected zebrafish suggests that ASK2 compound from a new strain of Streptomyces sp. was potent in mitigating MDR K. pneumoniae infection.

Characteristics of carbapenemase-producing Klebsiella pneumoniae as a cause of neonatal infection in Shandong, China

The goal of the present study was to examine the characteristics of carbapenem-resistant Klebsiella pneumoniae as a cause of neonatal infection. A total of 37 carbapenem-resistant Klebsiella pneumoniae-positive newborns hospitalized in Shandong Provincial Hospital, China between April 2011 and October 2013 were examined. Antibiotic susceptibility testing was performed using the agar dilution method and the Etest. Resistance genes were assessed by polymerase chain reaction (PCR) and sequencing. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) were used to determine the genotypes and homology of these isolates. Plasmids were analyzed by PFGE and conjugation experiments. The outer membrane proteins were examined by PCR and SDS-PAGE. All of the isolates were revealed to be resistant to the third and fourth generation cephalosporins and piperacillin-tazobactam. Tigecycline, colistin, levofloxacin and amikacin were successful against all of the isolates. The antibiotic resistance rates of aztreonam, gentamicin, trimethoprim-sulfamethoxazole and fosfomycin were 13.51, 48.64, 78.38 and 86.49%, respectively. Of the 37 cases, 25 isolates (67.57%) were bla_NDM-1 positive, 13 isolates (35.14%) were bla_IMP-4 positive and 1 isolate (2.70%) was bla_IMP-8 positive. Two isolates carried both bla_NDM-1 and bla_IMP-4. The isolate carrying 2-4 plasmids and bla_NDM-1 and bla_IMP-4 was transferable between strains. SDS-PAGE data indicated that outer membrane proteins remained present. PFGE revealed 7 distinct clusters, and MLST reported the presence of ST20, ST17, ST54, ST705 and ST290 sequences, which indicated that there was clone and plasmid spread between newborns. The main resistance mechanism of carbapenem-resistant Klebsiella pneumoniae was that the isolates expressed the carbapenemase resistance of bla_NDM-1 and bla_IMP-4 genes. The current study indicates that early detection of these genes may be helpful in infection prevention and control.

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 mortality in the Carbapenem-resistant Klebsiella pneumoniae infection: case control study

Carbapenem-resistant Klebsiella pneumoniae (CRKP) has been known as a nosocomial pathogen, both for the last 10 years in Turkey and for 20 years worldwide. Due to limited treatment options and high mortality rates, despite improvements in the field of medicine at the present time, CRKP is still a big threat for public health. This study was carried out between the dates of January 2010 and September 2014. Patients ≥18 who were hospitalized for at least 72 h and who also had CRKP growth were included in the study as a case group. In the same period patients, who were hospitalized in the same ward and did not have CRKP growth were selected as the control group. It was determined that no glycopeptides and steroids use nor tracheostomy as protective factors would be employed in terms of non-development of CRKP. Mechanical ventilation, tracheostomy, urinary catheter presence, central venous catheterization, nasogastric tube placement, advanced age, acute renal insufficiency, total parenteral nutrition, carbapenem, glycopeptide, and piperacillin tazobactam were all detected as risk factors in terms of CRKP infection development. As a result, rational usage of antibiotics for preventing infections developing with CRKP should be targeted.

Mortality markers in nosocomial Klebsiella pneumoniae bloodstream infection

PURPOSE

Klebsiella pneumoniae is the most common endogen agent for nosocomial infections. In this study, mortality markers were investigated in patients with nosocomial K. pneumoniae blood stream infection (NKp BSI).

METHODS

The characteristics of patients >16 years who had NKp BSI diagnosis by daily active surveillance between January 2012 and January 2016 were retrospectively evaluated. Patients who died until 28th day of the clinical follow up and those who survived until this time were statistically compared in terms of various risk factors.

RESULTS

One hundred ninety patients were included into the study. Mortality rate was 47.9%, carbapenem resistance was 43.2%. Statistical analysis have shown that in presence of post-NKp BSI sepsis, septic shock, following in intensive care unit (ICU), meropenem resistance, kidney failure, NKp BSI secondary to pneumonia, use of invasive instruments such as central venous catheter (CVC), urinary catheter (UC) and mechanical ventilator (MV), colostomy, transfusion and hemodialysis mortality was significantly higher. In patients admitted into the hospital for neurological disorders, pancreaticobiliary tract (PBT) diseases and patients who have undergone endoscopic retrograde cholangiopancreatography (ERCP) and patients in whom NKp BSI secondary to PBT infection mortality rate was lower.

CONCLUSIONS

Sepsis, septic shock, clinical conditions requiring ICU treatment and meropenem resistance increase mortality rates in NKp BSI significantly. Mortality was higher also in patients with NKp BSI secondary to pneumonia, in kidney failure and when invasive instruments were used. On the other hand, in patients who were admitted to the hospital for neurological disorders and PBT diseases mortality rate was lower.

Molecular epidemiology of carbapenem resistant gram-negative bacilli from infected pediatric population in tertiary - care hospitals in Medellín, Colombia: an increasing problem

BACKGROUND

Gram-negative bacilli are a cause of serious infections in the pediatric population. Carbapenem are the treatment of choice for infections caused by multidrug-resistant Gram-negative bacilli, but the emergence of carbapenem resistance has substantially reduced access to effective antimicrobial regimens. Children are a population vulnerable to bacterial infections and the emergence of resistance can worsen prognosis. The aim of this study is to describe the clinical and molecular characteristics of infections caused by carbapenem-resistant Gram-negative bacilli in pediatric patients from five tertiary-care hospitals in Medellín, Colombia.

METHODS

A cross-sectional study was conducted in five tertiary-care hospitals from June 2012 to June 2014. All pediatric patients infected by carbapenem-resistant Gram-negative bacilli were included. Clinical information for each patient was obtained from medical records. Molecular analyses included PCR for detection of bla VIM, bla IMP bla NDM, bla OXA-48 and bla KPC genes and PFGE and MLST for molecular typing.

RESULTS

A total of 59 patients were enrolled, most of them less than 1 year old (40.7 % n = 24), with a previous history of antibiotic use (94.9 %; n = 56) and healthcare-associated infections - predominately urinary tract infections (31.0 %; n = 18). Klebsiella pneumoniae was the most frequent bacteria (47.4 %), followed by Enterobacter cloacae (40.7 %) and Pseudomonas aeruginosa (11.9 %). For K. pneumoniae, KPC was the predominant resistance mechanism (85.7 %; n = 24) and ST14 was the most common clone (39.3 % n = 11), which included strains closely related by PFGE. In contrast, E. cloacae and P. aeruginosa were prevailing non-carbapenemase-producing isolates (only KPC and VIM were detected in 1 and 3 isolates, respectively) and high genetic diversity according to PFGE and MLST was found in the majority of the cases.

CONCLUSIONS

In recent years, increasing carbapenem-resistant bacilli in children has become in a matter of great concern. It is important to conduct systemic surveillance and take measures to prevent dissemination of multidrug-resistant bacteria.