Epidemiology of Klebsiella pneumoniae bloodstream infections in a teaching hospital: factors related to the carbapenem resistance and patient mortality

Incidence, antimicrobial resistance and mortality of Klebsiella pneumoniae bacteraemia in Shanghai, China, 2018-2022

BACKGROUND

Klebsiella pneumoniae (KP) accounts for high antimicrobial resistance and mortality rates of bloodstream infections (BSIs).

OBJECTIVES

To investigate incidence, antimicrobial resistance and risk factors for mortality of KP BSIs in East China.

METHODS

A retrospective study of patients with KP BSIs was conducted in a tertiary care hospital from 2018 to 2022. Medical records of all hospitalised patients with KP BSIs were reviewed and analysed. The incidence, antimicrobial resistance and mortality of KP BSIs were evaluated. The Kaplan-Meier method was used to plot survival curves and logistic regression was used to analyse risk factors for crude 30-day mortality.

RESULTS

A total of 379 inpatients with KP BSIs were enrolled. The incidence of patients with KP BSIs was fluctuating between 4.77 and 9.40 per 100,000 patient-days. The crude 30-day mortality rate of these patients was 26.39%. Of the 379 KPisolates, 197 (51.98%) were carbapenem-resistant (CR) and 252 (66.49%) were multidrug-resistant (MDR). All isolates showed the lowest resistance to tigecycline (13.77%) and polymyxin B (14.61%). Cases with MDR/CR isolates had significantly longer length of hospital stay, higher crude 30-day mortality and medical costs than non-MDR/non-CR isolates. Age, CR phenotype, paracentesis, indwelling central venous catheter (CVC), use of carbapenems, tetracyclines, polymyxins B, and irrational empiric treatment were independently associated with crude 30-day mortality.

CONCLUSION

MDR/CR KP BSIs are associated with increased mortality, healthcare costs and prolonged hospitalisation. Patients with advanced age, CR phenotype, paracentesis, CVC, exposure to some antibiotics, and irrational empirical antibiotic treatment are at higher mortality risk.

Molecular epidemiology and antimicrobial resistance profiles of Klebsiella pneumoniae isolates from hospitalized patients in different regions of China

Introduction

The increasing incidence of Klebsiella pneumoniae and carbapenem-resistant Klebsiella pneumoniae (CRKP) has posed great challenges for the clinical anti-infective treatment. Here, we describe the molecular epidemiology and antimicrobial resistance profiles of K. pneumoniae and CRKP isolates from hospitalized patients in different regions of China.

Methods

A total of 219 K. pneumoniae isolates from 26 hospitals in 19 provinces of China were collected during 2019-2020. Antimicrobial susceptibility tests, multilocus sequence typing were performed, antimicrobial resistance genes were detected by polymerase chain reaction (PCR). Antimicrobial resistance profiles were compared between different groups.

Results

The resistance rates of K. pneumoniae isolates to imipenem, meropenem, and ertapenem were 20.1%, 20.1%, and 22.4%, respectively. A total of 45 CRKP isolates were identified. There was a significant difference in antimicrobial resistance between 45 CRKP and 174 carbapenem-sensitive Klebsiella pneumoniae (CSKP) strains, and the CRKP isolates were characterized by the multiple-drug resistance phenotype.There were regional differences among antimicrobial resistance rates of K. pneumoniae to cefazolin, chloramphenicol, and sulfamethoxazole,which were lower in the northwest than those in north and south of China.The mostcommon sequence type (ST) was ST11 (66.7% of the strains). In addition, we detected 13 other STs. There were differences between ST11 and non-ST11 isolates in the resistance rate to amikacin, gentamicin, latamoxef, ciprofloxacin, levofloxacin, aztreonam, nitrofurantoin, fosfomycin, and ceftazidime/avibactam. In terms of molecular resistance mechanisms, the majority of the CRKP strains (71.1%, 32/45) harbored blaKPC-2, followed by blaNDM (22.2%, 10/45). Strains harboring blaKPC or blaNDM genes showed different sensitivities to some antibiotics.

Conclusion

Our analysis emphasizes the importance of surveilling carbapenem-resistant determinants and analyzing their molecular characteristics for better management of antimicrobial agents in clinical use.

Evolution of Antimicrobial Resistance in Klebsiella pneumoniae over 3 Years (2019-2021) in a Tertiary Hospital in Bucharest, Romania

BACKGROUND

The antimicrobial resistance (AMR) of Klebsiella pneumoniae recorded a steep upward trend over the last two decades, among which carbapenem-resistant Klebsiella pneumoniae (CRKP) is one of the most concerning strains considering the development and spread of AMR. The aim of this study was to analyze the evolution of AMR for Klebsiella pneumoniae and to describe the risk factors of AMR for Klebsiella pneumoniae, including the COVID-19 pandemic.

METHODS

We conducted a retrospective study on Klebsiella pneumoniae non-duplicative isolates collected from patients admitted to a tertiary hospital in Bucharest, Romania, from January 2019 to December 2021. We evaluated AMR changes by comparing resistance between 2019 and the mean of 2020-2021.

RESULTS

The rates of AMR increased for third-generation cephalosporins, carbapenems, aminoglycosides, fluoroquinolones, and colistin and decreased for trimethoprim/sulfamethoxazole (TMP/SMX), 45.7% in 2019 vs. 28.3% in 2021. A longer length of hospital stay (ꭓ2 = 49.68, p < 0.01); recent antibiotic consumption, RR = 1.38, 95% CI [1.21, 1.57]; and recent contact with hospital settings, RR = 1.54, 95% CI [1.32, 1.8] were risk factors for multidrug-resistant (MDR) Klebsiella pneumoniae.

CONCLUSIONS

The AMR of Klebsiella pneumoniae increased during 2020-2021 for most of the potential active antibiotics; only TMP/SMX resistance decreased, and it may represent a treatment option for CRKP or MDR Klebsiella pneumoniae infections. Decreasing the excessive use of antibiotics and the implementation of prevention and control measures in healthcare settings are mandatory for avoiding further increases in the AMR rate of Klebsiella pneumoniae.

The role of silver nanoparticles alone and combined with imipenem on carbapenem-resistant Klebsiella pneumoniae

AIMS

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections poses a significant threat to human health, necessitating urgent development of new antimicrobial agents. Silver nanoparticles (AgNPs), which are among the most widely used engineered nanomaterials, have been extensively studied. However, the impact of AgNPs on CRKP and the potential for drug resistance development remain inadequately explored.

METHODS AND RESULTS

In this study, broth dilution method was used to determine the minimum inhibitory concentration (MIC) was determined using the broth dilution method. Results indicated MIC values of 93.1 ± 193.3 µg ml-1 for AgNPs, 2.3 ± 5.1 µg ml-1 for AgNO3, and 25.1 ± 48.3 µg ml-1 for imipenem (IMI). The combined inhibitory effect of AgNPs and IMI on CRKP was assessed using the checkerboard method. Moreover, after 6-20 generations of continuous culture, the MIC value of AgNPs increased 2-fold. Compared to IMI, resistance of Kl. pneumoniae to AgNPs developed more slowly, with a higher fold increase in MIC observed after 20 generations. Whole-genome sequencing revealed four nonsynonymous single nucleotide polymorphism mutations in CRKP after 20 generations of AgNP treatment.

CONCLUSION

We have demonstrated that AgNPs significantly inhibit CRKP isolates and enhance the antibacterial activity of imipenem against Kl. pneumoniae. Although the development of AgNP resistance is gradual, continued efforts are necessary for monitoring and studying the mechanisms of AgNP resistance.

Risk factors of Carbapenem-resistant Enterobacterales intestinal colonization for subsequent infections in hematological patients: a retrospective case-control study

Objective

Infections caused by Carbapenem-resistant Enterobacterales (CRE) have high treatment costs, high mortality and few effective therapeutic agents. This study aimed to determine the risk factors for progression from intestinal colonization to infection in hematological patients and the risk factors for 30-day mortality in infected patients.

Methods

A retrospective case-control study was conducted in the Department of Hematology at Shandong Provincial Hospital affiliated to Shandong First Medical University from April 2018 to April 2022. Patients who developed subsequent infections were identified as the case group by electronic medical record query of patients with a positive rectal screen for CRE colonization, and patients who did not develop subsequent infections were identified as the control group by stratified random sampling. Univariate analysis and logistic regression analysis determined risk factors for developing CRE infection and risk factors for mortality in CRE-infected patients.

Results

Eleven hematological patients in the study developed subsequent infections. The overall 30-day mortality rate for the 44 hematological patients in the case-control study was 11.4% (5/44). Mortality was higher in the case group than in the control group (36.5 vs. 3.0%, P = 0.0026), and septic shock was an independent risk factor for death (P = 0.024). Univariate analysis showed that risk factors for developing infections were non-steroidal immunosuppressants, serum albumin levels, and days of hospitalization. In multivariable logistic regression analysis, immunosuppressants [odds ratio (OR), 19.132; 95% confidence interval (CI), 1.349-271.420; P = 0.029] and serum albumin levels (OR, 0.817; 95% CI, 0.668-0.999; P = 0.049) were independent risk factors for developing infections.

Conclusion

Our findings suggest that septic shock increases mortality in CRE-infected hematological patients. Hematological patients with CRE colonization using immunosuppressive agents and reduced serum albumin are more likely to progress to CRE infection. This study may help clinicians prevent the onset of infection early and take measures to reduce mortality rates.

Characteristics of Klebsiella pneumoniae pyogenic liver abscess from 2010-2021 in a tertiary teaching hospital of South China

OBJECTIVES

Pyogenic liver abscess (PLA) is a severe and potentially fatal infectious disease. Klebsiella pneumoniae (K. pneumoniae) is the predominant pathogen responsible for PLA. This study aims to investigate the clinical characteristics and prognostic factors of K. pneumoniae-induced pyogenic liver abscess (KP-PLA), particularly those caused by carbapenem-resistant K. pneumoniae (CRKP).

METHODS

Analyses were performed on PLA patients from January 2010 to December 2021, to investigate the differences of K. pneumoniae from other etiologically infected PLA patients. Univariate and multivariate logistic regression analyses were used to compare prognostic factors between patients with carbapenem-resistant K. pneumoniae PLA (CRKP-PLA) and patients with carbapenem-sensitive K. pneumoniae PLA.

RESULTS

Univariate analysis demonstrated a significant association between KP-PLA and factors including diabetes mellitus (P < 0.001), cholecystitis and cholelithiasis (P = 0.032), single abscess (P = 0.016), and abscesses with a diameter over 50 mm (P = 0.004). The CRKP group exhibited a higher prevalence of therapeutic interventions before K. pneumoniae infection, including abdominal surgery, mechanical ventilation, sputum suction, tracheal cannula, routine drainage of the abdominal cavity, and peripherally inserted central venous catheters (P < 0.05). Multivariate logistic regression analysis revealed that admission to the intensive care unit was an independent risk factor associated with CRKP-PLA (odds ratio 36; 95% confidence interval 1.77-731.56; P = 0.020).

CONCLUSION

The KP-PLA patients were significantly associated with diabetes and were more likely to have single abscesses larger than 50 mm. PLA patients with a history of admission to intensive care unit or invasive therapeutic procedures should be given special consideration if combined with CRKP infection.

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.

Carbapenemase-Producing Klebsiella pneumoniae Infections in Diabetic and Nondiabetic Hospitalized Patients

BACKGROUND

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection has recently attracted widespread attention due to its limited treatment options and significant morbidity and mortality rates. This study aimed to examine the relationship between risk factors and antimicrobial resistance in individuals with and without diabetes for the development of carbapenemase-producing K. pneumoniae infections.

METHODS

Between May 2019 and January 2021, a prospective study involving patients with and without diabetes who were infected with K. pneumonia, was carried out in a tertiary care hospital. Six hundred K. pneumoniae isolates were collected from various clinical samples, such as pus/wound samples, urine, respiratory samples, blood, and body fluids. An antimicrobial susceptibility test in K. pneumoniae was performed and compared between diabetics and nondiabetics. Univariate and multivariate logistic regression were used to identify independent risk factors for K. pneumoniae infections in the diabetic group and nondiabetic group separately. Multiplex PCR was used to detect genes that produce carbapenemase.

RESULTS

A total of 600 patients were infected with K. pneumoniae, with 300 (50%) being diabetic and 300 (50%) being nondiabetic. We found that diabetics had higher antimicrobial resistance to numerous routinely used drugs for infection than the nondiabetic group. In the multivariate analysis of the variables, it was found that immunosuppressive therapy, prior antibiotic use, mechanical ventilation, and urinary catheter use were all significant risk factors influencing the development of K. pneumoniae infections in diabetic patients. Diabetics had a higher prevalence of carbapenemase-producing K. pneumoniae than nondiabetics. Outcome measures in K. pneumoniae patients revealed that the diabetic group had considerably higher infection-related mortality.

CONCLUSION

We found that CRKP infection was associated with higher resistance to antibiotics in the diabetic group. Furthermore, the diabetic group had a higher prevalence of carbapenemase-producing K. pneumoniae than the nondiabetic group. Crucially, in order to lower mortality without worsening antibiotic resistance and metabolic damage, more focus has to be placed on sensible and efficient antibiotic and supportive care therapies.

Factors Associated with Extended-Spectrum β-Lactamases and Carbapenem-Resistant Klebsiella pneumoniae Bloodstream Infections: A Five-Year Retrospective Study

Klebsiella pneumoniae is one of the leading causes of nosocomial infections. It has been estimated that nosocomial infection by Klebsiella pneumoniae comprises 3-8% of all nosocomial infections. Klebsiella pneumoniae bloodstream infections (BSIs) occur worldwide with varying mortality. Resistant strains, like those producing extended-spectrum beta-lactamases (ESBL) and carbapenemases, are becoming increasingly common, especially in hospital settings, posing therapeutic challenges. In this article, we aimed to study the epidemiology and risk factors of BSIs due to resistant Klebsiella pneumoniae strains in the period 1 January 2014-31 December 2018 at the Nicosia General Hospital, the largest tertiary hospital in Cyprus. Data on demographics, co-morbidities, prior hospitalization, prior intensive care unit (ICU) admission, previous antimicrobial use, nosocomial acquisition of the infection, the presence of a prosthetic device or surgery, and the primary site of infection were retrospectively recorded. Associations between the detection of ESBL Klebsiella pneumoniae BSIs and factors/covariates were examined using logistic regression. This study involved 175 patients with BSI caused by Klebsiella pneumoniae. Of these, 61 BSIs were caused by ESBL strains, 101 by non-ESBL, and 13 by carbapenem-resistant (CR) strains. In univariable analyses, age, sex, heart disease, antimicrobial use during current admission, previous hospitalization (ward or ICU), and primary BSI were associated with the presence of an ESBL strain. Antibiotic use during current admission and heart disease remained statistically significantly associated with ESBL Klebsiella pneumoniae BSI in multivariable models. Antibiotic use during current admission, respiratory infection, and a recent history of surgery were more prevalent among CR Klebsiella pneumoniae BSI patients than among non-CR Klebsiella pneumoniae BSI patients. Our study showed that recent antimicrobial use and heart disease were associated with BSI due to ESBL-producing Klebsiella pneumoniae. This finding could inform clinical practice in hospital settings.

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.

Clinical characteristics of carbapenem-resistant Klebsiella pneumoniae infection/colonisation in the intensive care unit: a 9-year retrospective study

OBJECTIVES

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection/colonisation has been reported in hospitals. The clinical characteristics of CRKP infection/colonisation in the intensive care unit (ICU) have received little attention. This study aims to investigate the epidemiology and extent of K. pneumoniae (KP) resistance to carbapenems, the sources of CRKP patients and CRKP isolates, and the risk factors for CRKP infection/colonisation.

DESIGN

Retrospective single-centre study.

DATA SOURCE

Clinical data were obtained from electronic medical records.

PARTICIPANTS

Patients isolated with KP in the ICU from January 2012 to December 2020.

MAIN OUTCOME MEASURES

The prevalence and changing trend of CRKP were determined. The extent of KP isolates resistance to carbapenems, the specimen types of KP isolates, and the sources of CRKP patients and CRKP isolates were all examined. The risk factors for CRKP infection/colonisation were also assessed.

RESULTS

The rate of CRKP in KP isolates raised from 11.11% in 2012 to 48.92% in 2020. CRKP isolates were detected in one site in 266 patients (70.56%). The percentage of CRKP isolates not susceptible to imipenem increased from 42.86% in 2012 to 98.53% in 2020. The percentage of CRKP patients from general wards in our hospital and other hospitals gradually converged in 2020 (47.06% vs 52.94%). CRKP isolates were mainly acquired in our ICU (59.68%). Younger age (p=0.018), previous admission (p=0.018), previous ICU stay (p=0.008), prior use of surgical drainage (p=0.012) and gastric tube (p=0.001), and use of carbapenems (p=0.000), tigecycline (p=0.005), β-lactams/β-lactamase inhibitors (p=0.000), fluoroquinolones (p=0.033), and antifungal drugs (p=0.011) within the prior 3 months were independent risk factors for CRKP infection/colonisation.

CONCLUSIONS

Overall, the rate of KP isolates resistance to carbapenems increased, and the severity of this resistance significantly increased. Intensive and local infection/colonisation control measures are necessary for ICU patients, especially those with risk factors for CRKP infection/colonisation.

Phages for treatment of Klebsiella pneumoniae infections

Klebsiella pneumoniae is an opportunistic pathogen involved in both hospital- and community-acquired infections. K. pneumoniae is associated with various infections, including pneumonia, septicemia, meningitis, urinary tract infection, and surgical wound infection. K. pneumoniae possesses serious virulence, biofilm formation ability, and severe resistance to many antibiotics especially hospital-acquired strains, due to excessive use in healthcare systems. This limits the available effective antibiotics that can be used for patients suffering from K. pneumoniae infections; therefore, alternative treatments are urgently needed. Bacteriophages (for short, phages) are prokaryotic viruses capable of infecting, replicating, and then lysing (lytic phages) the bacterial host. Phage therapy exhibited great potential for treating multidrug-resistant bacterial infections comprising K. pneumoniae. Hence, this chapter emphasizes and summarizes the research articles in the PubMed database from 1948 until the 15th of December 2022, addressing phage therapy against K. pneumoniae. The chapter provides an overview of K. pneumoniae phages covering different aspects, including phage isolation, different morphotypes of isolated phages, in vitro characterization, anti-biofilm activity, various therapeutic forms, in vivo research and clinical studies.

Clinical characteristics, risk factors and outcomes of Klebsiella pneumoniae pneumonia developing secondary Klebsiella pneumoniae bloodstream infection

Purpose

The clinical characteristics of Klebsiella pneumoniae (KP) pneumonia and KP bloodstream infection (KP-BSI) are often reported, while the risk factors for KP pneumonia developing into secondary KP-BSI (KP-pneumonia/KP-BSI) are largely unknown. Therefore, this study attempted to investigate the clinical characteristics, risk factors and outcomes of KP-pneumonia/KP-BSI.

Methods

A retrospective observational study was conducted at a tertiary hospital between January 1, 2018, and December 31, 2020. The patients were divided into groups of KP pneumonia alone and KP pneumonia/KP-BSI, and the clinical information were collected from medical records electronic system.

Results

A total of 409 patients were finally recruited. According to the multivariate logistic regression analysis, male sex (adjusted odds ratio [aOR] 3.7; 95% CI, 1.44–9.5), immunosuppression (aOR, 13.52; 95% CI, 2.53,72.22), APACHE II score higher than 21 (aOR, 3.39; 95% CI, 1.41–8.12), serum procalcitonin (PCT) levels above 1.8 ng/ml (aOR, 6.37; 95% CI, 2.67–15.27), ICU stay of more than 2.5 days before pneumonia onset (aOR, 1.09; 95% CI, 1.02,1.17), mechanical ventilation (aOR, 4.96; 95% CI, 1.2,20.5), Klebsiella pneumoniae isolates producing extended spectrum β-lactamase (ESBL-positive KP) (aOR, 12.93; 95% CI, 5.26–31.76), and inappropriate antibacterial therapy (aOR, 12.38; 95% CI, 5.36–28.58) were independent factors of KP pneumonia/KP BSI. In comparison with the patients with KP pneumonia alone, the patients with KP pneumonia/KP BSI showed an almost 3 times higher incidence of septic shock (64.4% vs. 20.1%, p < 0.01), a longer duration of mechanical ventilation, and longer lengths of ICU stay and total hospital stay (median days, 15 vs. 4,19 vs. 6, 34 vs. 17, respectively, both p < 0.01). Additionally, the overall in-hospital crude mortality rate in the patients with KP-pneumonia/KP-BSI was more than two times higher than that in those with KP pneumonia alone (61.5% vs. 27.4%, p < 0.01).

Conclusion

Factors including male sex, immunosuppression, APACHE II score higher than 21, serum PCT levels above 1.8 ng/ml, ICU stay of more than 2.5 days before pneumonia onset, mechanical ventilation, ESBL-positive KP, and inappropriate antibacterial therapy are independent risk factors for KP pneumonia/KP-BSI. Of note, the outcomes in patients with KP pneumonia worsen once they develop secondary KP-BSI, which merits more attention.

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.

Retrospective Analysis of Epidemiology, Risk Factors, and Outcomes of Health Care-Acquired Carbapenem-Resistant Klebsiella pneumoniae Bacteremia in a Chinese Tertiary Hospital, 2010-2019

INTRODUCTION

In the present study, we aimed to describe the proportion of carbapenem-resistant Klebsiella pneumoniae bloodstream infection (CRKP-BSI) in KP-BSI in one Chinese tertiary hospital over 10 years and determine the risk factors and outcomes of CRKP-BSI.

METHODS

We retrospectively analyzed clinical and microbiological data of patients with KP-BSI from January 2010 to December 2019 to identify risk factors, clinical features, and outcomes using multivariate logistic regression analysis. KP-BSI only included monomicrobial BSI and health care-acquired BSI.

RESULTS

Among the total 687 isolates of KP-BSI in this study, the rate of CRKP was 39.0% (268/687); this rate in the intensive care unit (ICU) was 65.6% and that in seven high-risk departments (including four ICUs, respiratory medicine, gastroenterology medicine, and hepatobiliary surgery) was 74.6%. The annual rate of CRKP in KP-BSI ranged from 0.0% in 2010 to 54.5% in 2019. The 28-day mortality was 36.2% in patients with CRKP-BSI and 11.7% in those with carbapenem-susceptible K. pneumoniae (CSKP) BSI. Multivariable logistic regression analysis showed that prior ICU stay (odds ratio [OR] 2.485, P < 0.001), hospital stay ≥ 30 days prior to BSI (OR 1.815, P = 0.007), prior mechanical ventilation (OR 2.020, P = 0.014), prior urinary catheter (OR 1.999, P = 0.003), prior carbapenem use (OR 3.840, P < 0.001), hepatobiliary disease (OR 2.943, P < 0.001), pancreatitis (OR 2.700, P = 0.026), and respiratory disease (OR 2.493, P = 0.009) were risk factors of CRKP-BSI. Patients with a first admission (OR 0.662, P = 0.046) had a lower percentage of CRKP-BSI.

CONCLUSION

The rapidly rising rate of CRKP-BSI in KP with high mortality requires increased attention. Exposure to carbapenems, ICU stay, invasive mechanical ventilation or urinary catheter, prolonged hospital stay, hepatobiliary disease, pancreatitis, and respiratory disease were found to be risk factors for CRKP-BSI. Strict control measures should be implemented to prevent the emergence and spread of CRKP, especially in high-risk departments.

Long Term Characteristics of Clinical Distribution and Resistance Trends of Carbapenem-Resistant and Extended-Spectrum β-Lactamase Klebsiella pneumoniae Infections: 2014-2022

Purpose

Through long-term and large sample size statistical analysis, we revealed the pattern of Klebsiella pneumoniae (KP) infection and drug resistance and provided epidemiological data for the treatment and prevention and control of multidrug-resistant bacterial infection in our hospital.

Patients and Methods

Strains were identified using the BD Phoenix^TM100 system, minimal inhibitory concentration of antibiotics were determined by the broth method, and data were statistically analyzed using WHONET 5.6 and SPSS27.0.

Results

The isolation rate of KP from Enterobacteriaceae (26.2%, 4547/17358) in our hospital showed an increasing annual trend, ranking second only to Escherichia coli. Carbapenem-resistant KP (CRKP) accounted for the highest proportion of carbapenem-resistant Enterobacteriaceae (72.2%, 431/597), showing an upward trend. Infected patients had a male-to-female ratio of approximately 2:1 and were mainly >60 years of age (66.2%), with intensive care units being the most commonly distributed department. Sputum was the most common specimen type (74.0%). Compared with spring and summer, autumn and winter were the main epidemic seasons for KP and extended-spectrum β-lactamase KP (ESBL-KP). The resistance rate of KP to common antibiotics was low, but all showed an increasing trend each year. ESBL-KP was >90% resistant to piperacillin, amoxicillin/clavulanic acid, and cefotaxime and less resistant to other common antibiotics, but showed an increasing trend in resistance to most antibiotics. CRKP resistance to common antibiotics was high, with resistance rates >90%, excluding amikacin (64.1%), gentamicin (87.4%), cotrimoxazole (44.3%), chloramphenicol (13.6%), and tetracycline (30.5%).

Conclusion

KP in our hospital mainly caused pulmonary infection in older men, which occurred frequently in autumn and winter, and the isolation and drug resistance rates showed an increasing trend. Age over 70 years, admission to intensive care unit, and urinary tract infection were found to be the risk factors for CRKP and ESBL-KP-resistance.

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.

Criteria Restricting Inappropriate Meropenem Empiricism (CRIME): a quasi-experimental carbapenem restriction pilot at a large academic medical centre

The broad-spectrum activity of carbapenems makes them appealing for empirical use; however, they are associated with development of Clostridioides difficile infection (CDI) and multidrug resistance. Selective carbapenem use is vital in maintaining their effectiveness. We examined the impact of meropenem restriction criteria on utilisation and patient outcomes. This quasi-experimental study was conducted at a single academic medical centre after medication use evaluation found frequent inappropriate meropenem utilisation. Antimicrobial stewardship-led restriction criteria were developed and implemented in February 2022. Investigators aimed to determine how restriction criteria affected meropenem utilisation across 8 weeks in the pre- (February-April 2020) versus post-implementation period (February-April 2022). The primary outcome was inappropriateness of meropenem utilisation. Secondary outcomes included days of therapy per 1000 patient-days (DOT/1000 PD), hospital length of stay (LOS), CDI Standardized Infection Ratio (SIR), and acquisition cost. Across the 8-week timeframes, reductions in inappropriate meropenem use (64.5% vs. 12.8%; P < 0.001), duration of therapy [5.8 (3.2-7.3) vs. 2.4 (1.0-5.5) days; P < 0.001] and utilisation (30.5 vs. 8.3 DOT/1000 PD; P < 0.001) pre- versus post-implementation were observed. Total meropenem orders decreased by 65% (P < 0.001). Median hospital LOS also decreased between periods [11.9 (7.8-20.4) vs. 9.2 (5.4-15.2) days], although not statistically significant (P = 0.051). There was no difference in CDI SIR (0.1 vs. 0.1; P = 0.99). Projected annual cost savings were ∼US$57 300. Implementation of antimicrobial stewardship-initiated restriction criteria can reduce inappropriate meropenem utilisation, overall number of orders, and total duration of therapy.

Risk factors and mortality for elderly patients with bloodstream infection of carbapenem resistance Klebsiella pneumoniae: a 10-year longitudinal study

Background

Bloodstream infection (BSI) caused by carbapenem resistant Klebsiella pneumoniae (CRKP), especially in elderly patients, results in higher morbidity and mortality. The purpose of this study was to assess risk factors associated with CRKP BSI and short-term mortality among elderly patients in China.

Methods

In this retrospective cohort study, we enrolled 252 inpatients aged ≥ 65 years with BSI caused by KP from January 2011 to December 2020 in China. Data regarding demographic, microbiological characteristics, and clinical outcome were collected.

Result

Among the 252 BSI patients, there were 29 patients (11.5%) caused by CRKP and 223 patients (88.5%) by carbapenem-susceptible KP (CSKP). The overall 28-day mortality rate of elderly patients with a KP BSI episode was 10.7% (27/252), of which CRKP BSI patients (14 / 29, 48.3%) were significantly higher than CSKP patients (13 / 223, 5.83%) (P < 0.001). Hypertension (OR: 13.789, [95% CI: 3.883–48.969], P < 0.001), exposure to carbapenems (OR: 8.073, [95% CI: 2.066–31.537], P = 0.003), and ICU stay (OR: 11.180, [95% CI: 2.663–46.933], P = 0.001) were found to be associated with the development of CRKP BSI in elderly patients. A multivariate analysis showed that isolation of CRKP (OR 2.881, 95% CI 1.228–6.756, P = 0.015) and KP isolated in ICU (OR 11.731, 95% CI 4.226–32.563, P < 0.001) were independent risk factors for 28-day mortality of KP BSI.

Conclusion

In elderly patients, hypertension, exposure to carbapenems and ICU stay were associated with the development of CRKP BSI. Active screening of CRKP for the high-risk populations, especially elderly patients, is significant for early detection and successful management of CRKP infection.

Outcomes and Risk Factors of Bloodstream Infections Caused by Carbapenem-Resistant and Non-Carbapenem-Resistant Klebsiella pneumoniae in China

Purpose

To compare antimicrobial resistance, virulence, clinical characteristics, and risk factors between carbapenem-resistant K. pneumoniae (CRKP) and carbapenem-susceptible K. pneumoniae (CSKP) isolates from patients with bloodstream infections (BSIs) in China.

Patients and Methods

The clinical data of 103 patients with K. pneumoniae BSI from 10 hospitals were retrospectively analyzed. The minimum inhibitory concentrations of 15 antibiotics against the bacteria were determined. A Galleria mellonella infection model was used to evaluate virulence of the isolates. Kaplan-Meier curves were calculated to evaluate the 28-day and in-hospital survival rates of the isolates. The risk factors for CRKP and CSKP infection and respective mortality rate were evaluated by univariate analysis, and independent risk factors were evaluated using the multivariate logistic regression model.

Results

Our results indicated that CRKP isolates were more resistant to most tested antibiotics than CSKP isolates. The G. mellonella infection model was used to demonstrate that CRKP isolates were more virulent than CSKP isolates. We found that in-hospital deaths occurred in 39.3% (22/56) of patients with CRKP BSIs and were significantly higher than those in patients with CSKP infections (19.1%, 9/47). Patients infected with CRKP isolates had poorer outcomes than those infected with the CSKP strains. For in-hospital mortality of CRKP BSIs, the independent risk factors included carbapenem-resistant Enterobacterales bacteremia and length of hospitalization after the onset of BSI.

Conclusion

Our findings confirm that CRKP isolates are more drug-resistant than CSKP isolates and are associated with poorer outcomes. To prevent CRKP infection, strict infection control strategies and active surveillance should be implemented in hospitals.

Characterization of the First Carbapenem-Resistant Pseudocitrobacter faecalis Harboring blaOXA-181 in China

With the wide use of carbapenems, carbapenem-resistant Enterobacterales have been increasingly reported worldwide. In this study, one bla_OXA-181-positive Pseudocitrobacter faecalis strain was isolated from the blood culture of a patient with a bloodstream infection in China, which was its first clinical report outside Pakistan. Species identification of P. faecalis was initially performed using MALDI-TOF/MS and further confirmed by 16S rRNA gene and housekeeping gene sequencing. The antimicrobial susceptibility testing was determined through the broth microdilution method, and their clonal relationship was analyzed by pulsed-field gel electrophoresis. To study the transmission and genetic structure of the bla_OXA-181 gene, a transformation test and whole-genome sequencing (WGS) were performed. The results of the antimicrobial susceptibility testing indicated this P. faecalis was resistant to carbapenems, quinolones, and commonly used β-lactam/β-lactamase inhibitor combinations. Through WGS and transformation experiments, bla_OXA-181 and qnrS1 genes causing antibiotic resistance were located on a 55,148-bp length IncX3 type plasmid with a truncated ColKp3 replicon gene. As a rare species of Enterobacterales, P. faecalis was clinically reported in China for the first time, and the bla_OXA-181 gene it carried was located on a globally disseminated IncX3 plasmid. The spread of such bacteria and antibiotic resistance requires more clinical attention.

Analysis of Risk Factors and Mortality of Patients with Carbapenem-Resistant Klebsiella pneumoniae Infection

Background

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection is associated with high mortality and has become a major public problem threatening patients. This study aimed to explore risk factors for death in patients with Klebsiella pneumoniae (KP) and identify risk factors for CRKP infection.

Methods

The study retrospectively analyzed clinical characteristics and microbiological data from patients infected with KP from January 2019 to October 2021 to identify risk factors and mortality, using multivariate logistic regression analysis and Cox regression analysis.

Results

A total of 214 KP inpatients were enrolled in our study. The in-hospital mortality rate was significantly higher in patients infected with CRKP (13/68, 19.12%) than carbapenem-susceptible KP (CSKP) (2/146, 1.37%) and the difference was statistically significant (P= 0.03). Multivariate Cox regression analysis showed CRKP isolation (HR 12.26, 95% CI 2.43-61.68, P = 0.002), lower TP (HR 10.50, 95% CI 1.33-82.76, P = 0.03), antibiotic days of therapy >15 (HR 0.08, 95% CI 0.01-0.56, P= 0.01) and length of stay (LOS) (HR 0.03, 95% CI 0.002-0.61, P= 0.02) were independent risk factors for death from KP. Additionally, intensive care unit (ICU) stay (OR 21.69, 95% CI 4.50-118.76, P< 0.001) and previous carbapenem exposure (OR 5.26, 95% CI 1.38-21.19, P= 0.02) are independent risk factors for CRKP.

Conclusion

Our findings showed that patients infected with CRKP have a higher in-hospital mortality rate. Identifying the independent risk factors for CRKP infection may contribute to the management of CRKP and reduce the mortality of KP patients.

Modelling of the transmission dynamics of carbapenem-resistant Klebsiella pneumoniae in hospitals and design of control strategies

Carbapenem-resistant Klebsiella pneumoniae (CRKP) has emerged as a major threat to global public health. Epidemiological and infection controls associated with CRKP are challenging because of several potential elements involved in a complicated cycle of transmission. Here, we proposed a comprehensive mathematical model to investigate the transmission dynamics of CRKP, determine factors affecting the prevalence, and evaluate the impact of interventions on transmission. The model includes the essential compartments, which are uncolonized, asymptomatic colonized, symptomatic colonized, and relapsed patients. Additionally, symptomatic colonized and relapsed patients were further classified into subpopulations according to their number of treatment failures or relapses. We found that the admission of colonized patients and use of antibiotics significantly impacted the endemic transmission in health care units. Thus, we introduced the treatment efficacy, defined by combining the treatment duration and probability of successful treatment, to characterize and describe the effects of antibiotic treatment on transmission. We showed that a high antibiotic treatment efficacy results in a significantly reduced likelihood of patient readmission in the health care unit. Additionally, our findings demonstrate that CRKP transmission with different epidemiological characteristics must be controlled using distinct interventions.

Molecular Epidemiology and Risk Factors of Carbapenem-Resistant Klebsiella Pneumoniae Bloodstream Infections in Wuhan, China

OBJECTIVE

The clinical characteristics and microbiological data of patients with K. pneumoniae bloodstream infections (BSI) from January 2018 to December 2020 were retrospectively analyzed to study the molecular epidemiology of Carbapenem-resistant Klebsiella pneumoniae (CRKP). We also aimed to identify the risk factors for the development of CRKP BSI.

METHODS

This retrospective study was conducted at Renmin Hospital of Wuhan University from January 2018 to December 2020. The date of non-duplicate K. pneumoniae isolates isolated from blood samples was identified using the microbiology laboratory database. The data from patients diagnosed with K. pneumoniae BSI were collected and analyzed.

RESULTS

From 2018 to 2020, there were 510 non-duplicated K. pneumoniae blood isolates, mainly distributed in the intensive care unit (ICU) (28.4%), that were identified in our research. These cases included 77 strains of CRKP and 433 strains of carbapenem-susceptible K. pneumoniae (CSKP). The resistance rate of K. pneumoniae to meropenem and imipenem increased from 11.2% in 2018 to 27.1% in 2020. Moreover, Compared with CSKP, all CRKP isolates showed multi-resistance to tested antibiotics. The phylogenetic analysis showed that the CRKP isolates could be grouped into four major clades, and multilocus sequence typing revealed that the isolates had considerable clonality. Overall, 8 sequence types (STs) of CRKP were detected, of which ST11 comprised the majority and clustered into clade 3. The most prevalent carbapenemase gene was bla_KPC (87%) among the CRKP isolates, followed by bla_NDM (9.1%) and bla_IMP (1.3%). A total of 74 (16.6%) patients with CRKP BSI and 373 (83.4%) patients with CSKP BSI were categorized as the case and control groups. The mortality in the CRKP group was 44.6%, and 11.5% in CSKP group (P<0.001). A multivariate analysis that a long hospital stay before BSI (OR=1.42, 95% CI 1.02-4.31, P=0.011), ICU hospitalization history (OR=3.30, 95% CI 1.35-8.05, P=0.002), and prior use of carbapenems (OR=3.33, 95% CI 1.29-7.27, P=0.001) and antifungals (OR=2.81, 95% CI 1.24-6.04, P<0.001) were independent risk factors for CRKP BSI.

CONCLUSION

ST11 is the predominant type of CRKP mediating inter-hospital transmission, and bla_KPC is the main carbapenemase gene harboured by CRKP blood isolates. ICU stay, prolonged hospitalization before BSI, and prior use of carbapenems and antifungals were independent risk factors for acquiring CRKP BSI. Our study may provide insights into early infection control practices.

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.

Clinical Characteristics, Risk Factors, and Outcomes of Patients with Polymicrobial Klebsiella pneumoniae Bloodstream Infections

Background

Polymicrobial Klebsiella pneumoniae bloodstream infection (KP-BSI) has been reported to account for more than 10% of all KP-BSI, but few studies have characterized polymicrobial KP-BSI. Our study investigated the clinical characteristics, risk factors, and outcomes of polymicrobial KP-BSI by comparing with monomicrobial KP-BSI.

Methods

We conducted a single-center retrospective cohort study of patients with KP-BSI from 1 January 2013 to 31 December 2018 and collected the clinical data by reviewing electronic medical records.

Results

Of the 818 patients with KP-BSI recruited, 13.9% (114/818) were polymicrobial KP-BSI. The severity of illness in polymicrobial and monomicrobial KP-BSI was similar, while the rate of resistance to carbapenems was obviously higher in polymicrobial KP-BSI (78.1% vs. 65.6%, p = 0.009). On multivariate analysis, hospitalization in burn ward (odds ratio (OR) 6.13, 95% confidence interval (CI) 2.00-18.76, p = 0.001) and intensive care unit (OR 2.39, 95% CI 1.05-5.43, p = 0.038) was independently associated with polymicrobial KP-BSI. Gram-negative bacteria accounted for the highest proportion (68.9%) among copathogens of polymicrobial KP-BSI, whereas gram-positive bacteria (22.9%) and Candida (8.2%) ranked the second and the third, respectively, with Acinetobacter baumannii being the most common (23.0%). Patients with polymicrobial KP-BSI had longer hospital days after BSI onset and total hospital days than patients with monomicrobial KP-BSI (median (interquartile range (IQR)), 19 (5, 39) vs. 12 (6, 25), 37 (21, 67) vs. 29 (16, 53), respectively, p < 0.05). The mortality did not differ between polymicrobial KP-BSI and monomicrobial KP-BSI (all p > 0.05).

Conclusions

It was observed that polymicrobial KP-BSI accounted for a significant proportion among all KP-BSI in the current study. Hospitalization in burn ward and intensive care unit was an independent risk factor for the development of polymicrobial KP-BSI. The patients with polymicrobial KP-BSI had a higher rate of carbapenem-resistant K. pneumoniae and might have poor outcomes compared to monomicrobial KP-BSI.

An Outbreak of Carbapenem-Resistant Klebsiella pneumoniae in an Intensive Care Unit of a Major Teaching Hospital in Chongqing, China

Background

Due to the critical condition and poor immunity of patients, the intensive care unit (ICU) has always been the main hospital source of multidrug-resistant bacteria. In recent years, with the large-scale use of antibiotics, the detection rate and mortality of carbapenem-resistant Klebsiella pneumoniae (CRKP) have gradually increased. This study explores the molecular characteristics and prevalence of CRKP isolated from the ICU ward of a tertiary hospital in China.

Methods

A total of 51 non-duplicated CRKP samples isolated from the ICU were collected from July 2018-July 2020. The enzyme production of the strains was preliminarily screened by carbapenemase phenotypic test, and drug-resistant and virulence genes were detected by PCR. The transferability of plasmid was verified by conjugation test. The minimal inhibitory concentration (MIC) was determined by microbroth dilution method and genetic diversity was detected by multilocus sequence typing and pulsed-field gel electrophoresis.

Results

bla_KPC-2 was the only carbapenemase detected. The major virulence genes were uge (100%), mrkD (94.1%), kpn (94.1%), and fim-H (72.5%), while wcag, ironB, alls and magA genes were not detected. One sequence type ST1373 strain, hypervirulent K. pneumoniae (hvKP), was detected. CRKP strains were highly resistant to quinolones, cephalosporins, aminoglycosides, and polymyxin, but susceptive to tigecycline and ceftazidime-avibactam. The success rate of conjugation was 12.2%, indicating the horizontal transfer of bla_KPC-2 . Homology analysis showed that there was a clonal transmission of ST11 CRKP in the ICU of our hospital.

Conclusion

The present study showed the outbreak and dissemination in ICU were caused by ST11 CRKP, which were KPC-2 producers, and simultaneously, also carried some virulence genes. ST11 CRKP persisted in the ward for a long time and spread among different areas. Due to the widespread dispersal of the transferable bla_KPC-2 plasmid, the hospital should promptly adopt effective surveillance and strict infection control strategies to prevent the further spread of CRKP. Ceftazidime-avibactam showed high effectiveness against CRKP and could be used for the treatment of ICU infections.

Multidrug-resistant mcr-1 gene-positive Klebsiella pneumoniae ST307 causing urinary tract infection in a cat

RESUMO

The Klebsiella pneumoniae (K. pneumoniae) bacterium is responsible for many opportunistic infections such as sepsis, and a multidrug-resistant (MDR) clone sequence type (ST) 307 has recently begun to spread. The objective of this study was to report the first occurrence of this virulent genotype, which was found in the context of a urinary infection in a domestic feline in Brazil. The K. pneumoniae isolate was identified from the urine of a 6-month-old male crossbreed cat using 16S rRNA sequencing. It was then subjected to antimicrobial susceptibility testing, followed by multilocus sequence typing analysis, and PCR detection of virulence and resistance genes. The antimicrobial susceptibility profile demonstrated that the isolate was MDR and associated with the presence of the colistin resistance gene (mcr-1). Genotyping allowed us to classify the isolate as K. pneumoniae ST307 with the presence of wabG, uge, and entB genes. MDR K. pneumoniae is important in human and veterinary medicine because it causes many types of infections. Clonal propagation of virulent or MDR genotypes such as K. pneumoniae ST307 is a global concern. This report of ST307 isolation from a urine sample in a domestic feline is the first in Brazil.

High Carbapenem Resistance Caused by VIM and NDM Enzymes and OprD Alteration in Nonfermenter Bacteria Isolated from a Libyan Hospital

Acinetobacter baumannii and Pseudomonas aeruginosa are among the most prevalent pathogens causing a wide range of serious infections in hospitalized patients and contaminating intensive care units and inanimate surfaces. The purpose of this study was to investigate the mechanism of carbapenem resistance in clinical and hospital environmental isolates of A. baumannii and P. aeruginosa recovered from a Libyan hospital. From a total of 82 Gram-negative bacteria, 8 isolates of A. baumannii and 3 isolates of P. aeruginosa exhibited resistance to imipenem with minimum inhibitory concentrations ranging from 16 to >32 μg/mL. Five isolates of A. baumannii harbored bla_OXA-23 gene, from which three isolates were collected from patients and two from hospital environment. Only one isolate harbored bla_NDM-1 gene, which was responsible for carbapenem resistance in A. baumannii. The OprD gene seems to be disturbed by an insertion sequence (IS) in two isolates and affected by polymorphism in one isolate. Pulsed-field gel electrophoresis results showed high genetic diversity among carbapenemase producing A. baumannii. This study highlights the dissemination of bla_OXA-23 and bla_NDM-1 genes in a Libyan setting. Therefore, infection prevention and control practices, antimicrobial stewardship initiatives, and antimicrobial resistance surveillance systems should be implemented to prevent the wide spread of antimicrobial resistance.

Genome-Based Analysis of Klebsiella spp. Isolates from Animals and Food Products in Germany, 2013-2017

The increase in infections with multidrug-resistant and virulent Klebsiella pneumoniae (K. pneumoniae) strains poses a serious threat to public health. However, environmental reservoirs and routes of transmission for Klebsiella spp. that cause infections in humans and in livestock animals are not well understood. In this study, we aimed to analyze the distribution of antibiotic resistance genes and important virulence determinants (ybt, clb, iro, iuc, rmpA/A2) among 94 Klebsiella spp. isolates from different animal and food sources isolated between 2013 and 2017 in Germany. Antibiotic susceptibility testing was performed, and the genomes were sequenced by Illumina and Nanopore technology. Genetic relationships were assessed by conducting core genome multilocus sequence typing (cgMLST). Kleborate was used to predict resistance and virulence genes; Kaptive was used to derive the capsule types. The results revealed that 72 isolates (76.6%) belonged to the K. pneumoniae sensu lato complex. Within this complex, 44 known sequence types (STs), 18 new STs, and 38 capsule types were identified. Extended-spectrum beta-lactamase (ESBL) genes were detected in 16 isolates (17.0%) and colistin resistance in one (1.1%) K. pneumoniae isolate. Virulence genes were found in 22 K. pneumoniae isolates. Overall, nine (9.6%) and 18 (19.1%) isolates possessed the genes ybt and iuc, respectively. Notably, aerobactin (iuc lineage 3) was only detected in K. pneumoniae isolates from domestic pigs and wild boars. This study provides a snapshot of the genetic diversity of Klebsiella spp. in animals and food products in Germany. The siderophore aerobactin was found to be more prevalent in K. pneumoniae strains isolated from pigs than other sources. Further investigations are needed to evaluate if pigs constitute a reservoir for iuc lineage 3.

Prevalence, risk factors and molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae in patients from Zhejiang, China, 2008-2018

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is emerging as a worldwide public health concern; however, the long-term molecular epidemiological surveillance of clinical CRKP in China is limited. We conducted a retrospective observational study (2008-2018) to assess the prevalence, susceptibility, risk factors and molecular epidemiology of clinical CRKP isolates. We found the prevalence of CRKP increased from 2.5%, 2008 to 15.8%, 2018. CRKP were significantly more frequent among hospitalized patients from ICU, and it was significantly more likely to be isolated from the capital city (Hangzhou) and the patients aged ≥60 years. Additionally, seasons and specimen types were associated with CRKP infections. The main CRKP sequence type (ST) was ST11, and bla _KPC-2 was the most prevalent gene variant. Together these data reveal an increasing incidence and resistance trends among CRKP, especially the ST11-bla _KPC-2-CRKP, in Zhejiang, during 2008-2018. Our findings are important for hospitals to limit its dissemination and optimize antibiotic administration.

Hospital Acquired Bloodstream Infection by Multi Drug Resistant Organisms-Alarming and Challenging Issue in the Intensive Care Units at Present Era

Hospital-acquired bloodstream infections (BSIs) cause high mortality in the intensive care units (ICUs) compared to wards. Furthermore, the isolation of multidrug resistant (MDR) organisms in ICUs add to the gravity of the condition making the treatment a bigger challenge. The present study was aimed to evaluate the prevalence, spread, and the possible MDR organisms contributing to ICU-acquired BSI & the source of the secondary BSI in the ICUs. A prospective study was conducted in four ICU of tertiary teaching hospital over a period of six months. Patient that developed features of BSI within 48 hours after hospital admission were included in the present study Blood culture was performed by an automated BacT/ALERT®3D system. The source of secondary BSI was identified by analysing culture results for the samples other than blood. These samples were taken within 48 hours of the patient’s blood culture test being positive. A total of 50 patients (25%) had an ICU acquired bloodstream infection. Out of 50 patients, 74% of them had bacterial etiology. Thirty one patients (62%) among them developed multidrug resistant bacteraemia. Fifty six percent of Gram negative bacilli were multi drug resistant. The resistance to carbapenem was 42%. The most common MDR Gram negative isolate was identified as Klebsiella pneumoniae (n=12; 38.7%,) and the most common source was pulmonary infection (26.7% (n=12). 42% of isolates in our study were carbapenem resistant suggesting the need for a proper antibiotic policy in the ICUs. Prolonged stay in the ICU with mechanical ventilation was the critical risk factor and ICU mortality was high (38%).

A risk score based on pediatric sequential organ failure assessment predicts 90-day mortality in children with Klebsiella pneumoniae bloodstream infection

Background

Klebsiella pneumoniae bloodstream infection (Kp-BSI) is a serious threat to pediatric patients. The objective of this study was to explore the risk factors, validate the prediction efficiency of pediatric Sequential Organ Failure Assessment (SOFA) and establish better early predictors of mortality in pediatric patients with Kp-BSI.

Methods

All children diagnosed with Kp-BSI were included in this retrospective cohort study from January 2009 to June 2019. Basic characteristics, symptoms and physical examinations, treatments, laboratory statistics, and SOFA at the onset of Kp-BSI were recorded. The Cox proportional hazard model and receiver operating characteristic curves were used to assess the association between the variables and the 90-day mortality and their predictive value. DeLong’s test of receiver operating characteristic curves and integrated discrimination improvement index were used to determine the improvement in predictive capacity of the modified SOFA models. A predictive score was developed using multivariate logistic regression.

Results

Of the 146 children enrolled, 33 (22.6%) patients died within 90 days. Hospitalization in the last 6 months, intra-abdominal source of infection, presence of organ failure, and altered levels of blood biomarkers, including C-reactive protein, albumin, and lactate were significant risk factors for 90-day mortality. The area under the curve (AUC) of SOFA for predicting 90-day mortality was 0.80 (95% CI 0.71–0.89). Moreover, we found that a prediction model combining SOFA with two other parameters, namely hospitalization in the last 6 months and intra-abdominal source of infection, was better at predicting mortality (AUC = 0.89, 95% CI 0.82–0.96; sensitivity = 0.86; specificity = 0.84). According to this novel risk model, we defined three statistically different groups: low-risk, medium-risk and high-risk groups, with an observed 90-day mortality of 5.4, 35.7, and 72.0%, respectively. With reference to the low-risk patients, the medium-risk and high-risk groups had a higher mortality, with hazard ratios of 8.36 (95% CI 3.60–27.83) and 20.27 (95% CI 7.47–54.95), respectively.

Conclusions

The modified SOFA may be better than the original score to predict 90-day mortality in pediatric patients with Kp-BSI. Future prospective studies are required to validate this novel scoring system in external cohorts.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-020-05644-w.

Risk Factors Affecting Clinical Outcome in Patients with Carbapenem-Resistant K. pneumoniae: A Retrospective Study

Background

The increased prevalence of carbapenem-resistant K. pneumoniae (CRKP) poses a great threat worldwide. Early identification of CRKP in patients is paramount. Moreover, fully understanding the risk factors affecting clinical outcome and actively providing targeted treatment can improve the cure rate of patients with CRKP. Therefore, our study aimed to describe the clinical characteristics and identify the risk factors affecting clinical outcomes in patients with CRKP.

Material/Methods

From January 2016 to September 2017, CRKP strains and clinical data from 97 hospitalized patients were collected. We first performed an antibiotic susceptibility test on CRKP strains using the Kirby-Bauer disc agar diffusion method. Logistic regression analysis was then performed to analyze risk factors.

Results

According to clinical outcome, among the 97 CRKP patients, 67 were in the effective group and 30 patients were in the noneffective group. Risk factors found to correlate with poor clinical outcome in patients with CRKP included ICU admission, arteriovenous catheterization, indwelling gastric tube, indwelling urethral catheter, tracheal intubation, mechanical ventilation, hypoproteinemia, and exposure to carbapenems. Multivariate analysis showed that hypoproteinemia (OR: 2.83, p=0.042), presence of an indwelling gastric tube (OR: 4.54, p=0.005), and exposure to carbapenems (OR: 2.77, p=0.045) negatively affected clinical outcome in patients with CRKP.

Conclusions

Adverse risk factors correlated with poor clinical outcomes in patients with CRKP were determined. This could be of help in identifying high-risk patients with whom clinicians should take extra precautions and adjust therapeutic strategy to supplement conventional basic treatment with additional measures.

Clinical and Economic Burden of Carbapenem-Resistant Infection or Colonization Caused by Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii: A Multicenter Study in China

Background: Carbapenem resistant Klebsiella pneumoniae (CRKP), Pseudomonas aeruginosa (CRPA), and Acinetobacter baumannii (CRAB) pose significant threats to public health. However, the clinical and economic impacts of CRKP, CRPA, and CRAB remain largely uninvestigated in China. This study aimed to examine the clinical and economic burden of CRKP, CRPA, and CRAB compared with carbapenem susceptible cases in China. Method: We conducted a retrospective and multicenter study among inpatients hospitalized at four tertiary hospitals between 2013 and 2015 who had K. pneumoniae, P. aeruginosa, and A. baumannii positive clinical samples. Propensity score matching (PSM) was used to balance the impact of potential confounding variables, including age, sex, insurance, number of diagnosis, comorbidities (disease diagnosis, and Charlson comorbidity index), admission to intensive care unit, and surgeries. The main indicators included economic costs, length of stay (LOS), and mortality rate. Results: We included 12,022 inpatients infected or colonized with K. pneumoniae, P. aeruginosa, and A. baumannii between 2013 and 2015, including 831 with CRKP and 4328 with carbapenem susceptible K. pneumoniae (CSKP), 1244 with CRPA and 2674 with carbapenem susceptible P. aeruginosa (CSPA), 1665 with CRAB and 1280 with carbapenem susceptible A. baumannii (CSAB). After PSM, 822 pairs, 1155 pairs, and 682 pairs, respectively were generated. Compared with carbapenem-susceptible cases, those with CRKP, CRPA, and CRAB were associated with statistically significantly increased total hospital cost ($14,252, p < 0.0001; $4605, p < 0.0001; $7277, p < 0.0001) and excess LOS (13.2 days, p < 0.0001; 5.4 days, p = 0.0003; 15.8 days, p = 0.0004). In addition, there were statistically significantly differences in hospital mortality rate between CRKP and CSKP, and CRAB and CSAB group (2.94%, p = 0.024; 4.03%, p = 0.03); however, the difference between CRPA and CSPA group was marginal significant (2.03%, p = 0.052). Conclusion: It highlights the clinical and economic impact of CRKP, CRPA, and CRAB to justify more resources for implementing antibiotic stewardship practices to improve clinical outcomes and to reduce economic costs.

Increased Antimicrobial Resistance among Sputum Pathogens from Patients with Hyperglycemia

Background

Glucose management is of great significance. Infection and hyperglycemia are a vicious circle. This study was conducted to describe distribution and antimicrobial resistance of bacteria isolated from patients with normoglycemia, hyperglycemia, or diabetes on admission.

Methods

A retrospective study was conducted in a teaching hospital from January 2015 to March 2017. Bacteria were identified by the Vitek 2 automated system and antimicrobial susceptibility determined.

Results

A total of 1,163 patients were included: 582 with normoglycemia, 292 with hyperglycemia and 289 with diabetes. Enterobacter, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterococcus faecium were the main species isolated from these patients, with 1,616 unduplicated isolates from sputum samples. Patients with hyperglycemia were more prone to carry more than one species, and the rate of multidrug-resistant K. pneumoniae and methicillin-resistant S. aureus was higher in this group. K. pneumoniae from hyperglycemia patients demonstrated increased resistance to carbapenems, especially imipenem (p=0.002) and meropenem (p=0.003), than those isolated from patients with normoglycemia or diabetes. No significance was detected for K. pneumoniae, A. baumannii, or P. aeruginosa between nondiabetes and diabetes patients. In addition, hyperglycemia patients had a higher rate of ICU admission (p=0.035) and a lower survival rate (p<0.001).

Conclusion

Patients with hyperglycemia were more prone to carry bacteria, especially multidrug-resistant K. pneumoniae and methicillin-resistant S. aureus. Assessing glucose on admission is of great significance in predicting bacterial carriage and antimicrobial resistance.

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 and mortality for patients with Bloodstream infections of Klebsiella pneumoniae during 2014-2018: Clinical impact of carbapenem resistance in a large tertiary hospital of China

BACKGROUND

Bloodstream infection (BSI) caused by Klebsiella pneumoniae (KP), especially carbapenem-resistant KP (CRKP), results in high morbidity and mortality.

AIMS

We aim to identify risk factors that associated with the mortality of patients with KP BSI, as well as predictors of developing CRKP BSI.

RESULTS

In this retrospective cohort study, we examined 285 inpatients with BSI caused by KP in a tertiary hospital in China between 2014 and 2018, and 46 patients were infected with CRKP. We identified that hematological tumor (odds ratio (OR): 8.359, [95% CI: 2.162-33.721], P=0.002), CRKP isolation (OR: 7.766, [95% CI: 2.796-21.576], P=0.001), chronic lung disease (OR: 5.020, [95% CI: 1.275-19.768], P=0.020), and septic shock (OR: 4.591, [95% CI: 1.686-12.496], P=0.003) were independent risk factors for the death of KP BSI. A 28-day mortality of KP BSI score ranging from 0 to 22 was developed based on the above 4 independent variables. Our scoring system revealed that the 28-day mortality were 9.14%, 35.29%, 38.10 %, 75% and 100% for carriers with a score of 0, 5, 6-10, 11-13 and ≥14, respectively. Additionally, CRKP infection were independently associated with intensive care unit stay (OR: 5.506, [95% CI: 2.258-13.424], P=0.001), exposure to antifungals (OR: 4.679, [95% CI: 2.065-10.063], P=0.001), exposure to fluoroquinolones (OR: 2.892, [95% CI: 1.151-7.267], P=0.020), and the number of isolated bacterial species from the patient ≥ 3 (OR: 2.414, [95% CI: 1.306-4.463], P=0.005).

CONCLUSION

Our study may be useful for the reduction of the mortality of patients with KP BSI and the prevention of developing CRKP BSI in hospitals.

Mortality risk of bloodstream infection caused by either Escherichia coli or Klebsiella pneumoniae producing extended-spectrum β-lactamase: a prospective cohort study

Objective

Several studies reported that infection of extended-spectrum β lactamase (ESBL)-producing Escherichia coli (E. coli) or Klebsiella pneumoniae (K. pneumoniae) contributed to higher mortality rates but others found it was not associated with mortality. A prospective cohort study which involved 72 patients was conducted to assess the risk of mortality of bloodstream infection due to ESBL-producing K. pneumoniae or E. coli as compared to those infected by either K. pneumoniae or E. coli which not produce ESBL.

Result

Mortality in the group of patients infected with ESBL-producing bacteria was 30.6%, whereas in another group which was infected with non ESBL-producing bacteria was 22.2% (p = 0.59). Kaplan–Meier’s analysis showed that the survival rate during 14-days follow-up among these two group was not significantly different (p = 0.45) with hazard ratio 1.41 (95% CI  0.568–3.51). Stratification analysis found that adult and elderly patients, patients with sign of leukocytosis, and patients treated with carbapenem were modifier effect variables.

Distribution and drug resistance of pathogenic bacteria in emergency patients

BACKGROUND

Antibiotic resistance has become a global threat for human health, calling for rational use of antibiotics.

AIM

To analyze the distribution and drug resistance of the bacteria, providing the prerequisite for use of antibiotics in emergency patients.

METHODS

A total of 2048 emergency patients from 2013 to 2017 were enrolled. Their clinical examination specimens were collected, followed by isolation of bacteria. The bacterial identification and drug susceptibility testing were carried out.

RESULTS

A total of 3387 pathogens were isolated. The top six pathogens were Acinetobacter baumannii (660 strains), Staphylococcus aureus (436 strains), Klebsiella pneumoniae (347 strains), Pseudomonas aeruginosa (338 strains), Escherichia coli (237 strains), and Candida albicans (207 strains). The isolation rates of these pathogens decreased year by year except Klebsiella pneumoniae, which increased from 7.1% to 12.1%. Acinetobacter baumannii is a widely-resistant strain, with multiple resistances to imipenem, ciprofloxacin, minocycline and tigecycline. The Staphylococcus aureus had high resistance rates to levofloxacin, penicillin G, and tetracycline. But the susceptibility of it to vancomycin and tigecycline were 100%. Klebsiella pneumoniae had high resistance rates to imipenem, cefoperazone/sulbactam, amikacin, and ciprofloxacin, with the lowest resistance rate to tigecycline. The resistance rates of Pseudomonas aeruginosa to cefoperazone/sulbactam and imipenem were higher, with the resistance rate to amikacin below 10%. Besides, Escherichia coli had high resistance rates to ciprofloxacin and cefoperazone/sulbactam and low resistance rates to imipenem, amikacin, and tigecycline.

CONCLUSION

The pathogenic bacteria isolated from the emergency patients were mainly Acinetobacter baumannii, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. The detection rates of drug-resistant bacteria were high, with different bacteria having multiple drug resistances to commonly used antimicrobial agents, guiding the rational use of drugs and reducing the production of multidrug-resistant bacteria.

Clinical and virulence factors related to the 30-day mortality of Klebsiella pneumoniae bacteremia at a tertiary hospital: a case-control study

Klebsiella pneumoniae bacteremia is a critical clinical presentation that is associated with high mortality. However, extremely few studies have investigated the virulence factors related to mortality of K. pneumoniae bacteremia in patients. The present study elucidated clinical and virulence factors associated with the 30-day mortality of K. pneumoniae bacteremia at a tertiary hospital. The medical records of 129 patients with K. pneumoniae bacteremia admitted to Osaka City University Hospital between January 2012 and December 2018 were retrospectively reviewed. Patient background characteristics, antimicrobial regimens, and prognosis were evaluated. Additionally, virulence factors were assessed using multiplex polymerase chain reaction to elucidate their association with K. pneumoniae. The 30-day mortality was 10.9% in patients with K. pneumoniae bacteremia. The male-to-female ratio, age, and underlying disease did not differ between the non-survivor and survivor groups. Multivariate analysis showed that sepsis (odds ratio (OR), 7.46; p = 0.005) and iutA (OR, 4.47; p = 0.046) were independent predictors associated with the 30-day mortality of K. pneumoniae bacteremia. Despite the relatively low 30-day mortality of patients with K. pneumoniae bacteremia, the treatment of those with sepsis and those infected with K. pneumoniae harboring iutA may require careful management for improving their outcomes.

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.

The Clinical and Economic Impact of Antibiotic Resistance in China: A Systematic Review and Meta-Analysis

Antibiotic resistance (ABR) is one of the biggest threats to global health, especially in China. This study aims to analyze the published literature on the clinical and economic impact of ABR or multi-drug resistant (MDR) bacteria compared to susceptible bacteria or non-infection, in mainland China. English and Chinese databases were searched to identify relevant studies evaluating mortality, hospital stay, and hospital costs of ABR. A meta-analysis of mortality was performed using a random effects model. The costs were converted into 2015 United States (US) dollars. Of 13,693 studies identified, 44 eligible studies were included. Twenty-nine investigated the impact of ABR on hospital mortality, 37 were focused on hospital stay, and 21 on hospital costs. Patients with ABR were associated with a greater risk of overall mortality compared to those with susceptibility or those without infection (odds ratio: 2.67 and 3.29, 95% confidence interval: 2.18–3.26 and 1.71–6.33, p < 0.001 and p < 0.001, respectively). The extra mean total hospital stay and total hospital cost were reported, ranging from 3 to 46 days, and from US$238 to US$16,496, respectively. Our study indicates that ABR is associated with significantly higher mortality. Moreover, ABR is not always, but usually, associated with significantly longer hospital stay and higher hospital costs.

Antimicrobial resistance and risk factors for mortality of pneumonia caused by Klebsiella pneumoniae among diabetics: a retrospective study conducted in Shanghai, China

Purpose: To investigate antimicrobial resistance and risk factors for mortality of Klebsiella pneumoniae (KP) pneumonia in diabetics and nondiabetics. Patients and methods: A retrospective study was conducted among inpatients of KP pneumonia via electronic medical records in a territory hospital between January 2016 and June 2018. Antimicrobial resistance in KP pneumonia was compared between diabetics and nondiabetics. Independent risk factors for mortality in KP pneumonia were identified by univariate and multivariate logistic regression among diabetics and nondiabetics separately. Results: In this study, 456 patients with KP pneumonia were included. There were 156 cases with diabetes and 300 without diabetes. KP showed a lower antimicrobial resistance to a multitude of antimicrobials in pneumonia among diabetics than nondiabetics, namely aztreonam, cefotetan, sulperazone, meropenem, amikacin, tobramycin, sulfamethoxazole, and fosfomycin. In addition, carbapenem-resistant Klebsiella pneumoniae (CRKP) was more prevalent among nondiabetics than diabetics who were admitted to intensive care unit (ICU) (63.0% vs 45.1%, P = 0.038). Multivariable analysis showed that independent risk factors for in-hospital mortality (IHM) in KP pneumonia among diabetics differed from that among nondiabetics as well. Independent predictors for IHM of KP pneumonia among diabetics were male (OR: 5.89, 95% CI: 1.34-25.93, P = 0.019), albumin (ALB) < 35 g/L (OR: 7.00, 95% CI: 2.02-24.28, P = 0.002), bloodstream infection (BSI) (OR: 21.14, 95% CI: 3.18-140.72, P = 0.002), and invasive ventilation during hospitalization (OR: 8.00, 95% CI: 2.99-21.42, P < 0.001). In nondiabetics, independent predictors were higher CURB-65 score (OR: 1.92, 95% CI: 1.29-2.86, P = 0.001), CRKP (OR: 2.72, 95% CI: 1.07-6.90, P = 0.035), BSI (OR: 4.98, 95% CI: 1.34-18.50, P = 0.017), and ICU admission (OR: 4.06, 95% CI: 1.57-10.47, P = 0.004). Conclusion: In KP pneumonia, diabetics showed lower antimicrobial resistance and different independent risk factors for mortality compared with nondiabetics, in line with previous studies. Importantly, further attention should be paid on rational and effective antibiotic and supportive treatments in order to reduce mortality without aggravating antimicrobial resistance and metabolic damage among diabetics.

The use of predictive scores in the management of patients with carbapenem-resistant Klebsiella pneumoniae infection

INTRODUCTION

Carbapenem-resistant Klebsiella pneumoniae (CR-KP) infections are associated with high morbidity and mortality rates. A therapeutic approach based on the patient risk stratification could improve outcome and avoid antibiotic misuse. Areas covered: English literature search, from 2008 to 2018, was done using PubMed database. Risk factors for developing CR-KP infection in several settings were reviewed. Since, rectal carriage was a main risk factor for developing infection, we revised in deep clinical score to predict infection among colonized patients. Furthermore, we investigated overall and treatment-related risk factors for poor outcome in patients with CR-KP infection, in particular the carbapenem producing Enterobacteriacieae (CPE)-INCREMENT score. Finally, an algorithm, based on such scores, for the therapeutic management of patients with CR-KP colonization was commented. Expert opinion: The therapeutic approach analyzed in this review could help physicians to avoid antibiotic overuse as well as to start promptly with the most appropriate antibiotic regimen. However, it has to be validated in further studies, mainly among special population such as immunocompromised patients. The availability of new drugs, fast microbiology, and analysis of gut microbiome could significantly improve the management of CR-KP colonized and/or infected patients.

Polymicrobial Bacteremia Involving Klebsiella pneumoniae in Patients with Complicated Intra-Abdominal Infections: Frequency, Co-Pathogens, Risk Factors, and Clinical Outcomes

Background: Klebsiella pneumoniae has gained notoriety because of its high antibiotic resistance and mortality. We compared the clinical features and outcomes of polymicrobial bacteremia involving K. pneumoniae (PBKP). Patients and Methods: A retrospective observational study of patients with polymicrobial and monomicrobial bacteremia involving K. pneumoniae from January 2012 to December 2016 was performed. The expression of resistance and virulence genes of 27 strains was also compared by polymerase chain reaction (PCR). Results: Among the polymicrobial group, the most common accompanying micro-organism was Escherichia coli. No differences in the expression of resistance and virulence genes was found among the 27 strains collected from the group. The analysis of the outcomes revealed that the patients with PBKP were more likely to have recurrent blood stream infections (p = 0.038), longer intensive care unit (ICU) lengths of stay (p = 0.043), and a higher total hospitalization cost (p = 0.045). However, no substantial differences in mortality were found between the two groups. The multivariable analysis revealed that a longer hospital stay prior to the onset of bacteremia (>20 days) was an independent risk factor for PBKP (p = 0.034), and the Sequential Organ Failure Assessment (SOFA) score upon onset of infection (p = 0.013), the adequacy of source control (p < 0.001), and iron supplementation (p = 0.003) were identified as independent predictors of mortality in patients with KP bacteremia. Conclusions: The development of septic shock and the concomitant use of iron supplementation are associated with higher mortality in patients with KP bacteremia, and PBKP did not increase the mortality of these patients, possibly because of the ability of K. pneumoniae to obscure the effects of other bacteria. Thus, adequate source control is more important than high-dose antibiotic therapy and is linked to higher survival.

The impact of the national action plan on the epidemiology of antibiotic resistance among 352,238 isolates in a teaching hospital in China from 2015 to 2018

Background

We sought to understand the epidemiology and characteristics of antimicrobial resistance (AMR) and the impact of the National Action Plan (NAP) on AMR. This information will be critical to develop interventions and strengthen antibiotic stewardship in hospital settings in China.

Methods

Cross-sectional data collection from the hospital information management system from 1 January 2015 to 30 August 2018. Variables included patient age, sex, diagnosis, hospital department and antibiotic sensitivity test. T-test for two samples method was applied to compare the results before and after NAP implementation. Multivariate analysis with binary logistic regression was conducted to examine the associations of risk factors for antimicrobial resistance.

Results

In total there were 352,238 isolates in the final analysis after excluding contamination strains and isolates with incomplete information. More than 50% of patients were > 66 years old. 62% were male. 40% of the total samples were sputum. Among the total sample, the total resistance rate was 42% among all isolates. The rate of resistance to all antibiotics declined by 5.3% (95% CI 4.96-5.64%, p < 0.0001) and culture positivity rate declined by 9.8% (95% CI 9.22-10.34%, p < 0.0001) after NAP. Logistical regression showed that the NAP had effect with an adjusted odds ratio of 0.76 (95% CI 0.71-0.81, p = 0.002). Being male, age > 65 years, ICU department, diagnosed with certain diseases were more likely to be associated with antimicrobial resistance.

Conclusions

Antibiotic resistance rates were high in this teaching hospital. However, the introduction of the China NAP since 2016 followed by hospital policy emphasis was associated with a declining AMR trend. Policies will need to incorporate antimicrobial stewardship with a focus on certain departments, with infection control practices and with increases in vaccination coverage among elderly.

Infection-prevention and control interventions to reduce colonisation and infection of intensive care unit-acquired carbapenem-resistant Klebsiella pneumoniae: a 4-year quasi-experimental before-and-after study

Objective

To determine whether infection-prevention and control (IPC) interventions can reduce the colonisation and infection of intensive care unit (ICU)-acquired carbapenem-resistant Klebsiella pneumoniae (CRKP) in a general ICU ward in China.

Methods

We used a quasi-experimental before-and-after study design. The study was conducted in 4 stages: baseline period, January 2013-June 2013; IPC interventions period including de-escalation and targeted bundle interventions, July 2013-June 2014; modified IPC interventions period, July 2014-June 2015; and follow-up period, July 2015-June 2016. We used modified de-escalation interventions according to patient-risk assessments to prevent the transmission of CRKP.

Results

A total of 629 patients were enrolled in study. The incidence of ICU-acquired CRKP colonisation/infection was 10.08 (4.43-16.43) per 1000 ICU patient-days during the baseline period, and significantly decreased early during the IPC interventions, but the colonisation/infections reappeared in April 2014. During the modified IPC intervention and follow-up periods, the incidence of ICU-acquired CRKP colonisations/infections reduced to 5.62 (0.69-6.34) and 2.84 (2.80-2.89), respectively, with ongoing admission of cases with previously acquired CRKP. The incidence of ICU-acquired CRKP catheter-related bloodstream infections decreased from 2.54 during the baseline period to 0.41 during the follow-up period. The incidence of ventilator-associated pneumonia and skin and soft tissue infections showed a downward trend from 2.84 to 0.41 and from 3.4 to 0.47, respectively, with slight fluctuations.

Conclusions

Comprehensive IPC interventions including de-escalation and targeted bundle interventions showed a significant reduction in ICU-acquired CRKP colonisations/infections, despite ongoing admission of patients colonised/infected with CRKP.