Intra-hospital differences in antibiotic use correlate with antimicrobial resistance rate in Escherichia coli and Klebsiella pneumoniae: a retrospective observational study

Modelling the implementation of narrow versus broader spectrum antibiotics in the empiric treatment of E. coli bacteraemia

The implementation of new antimicrobial resistance stewardship programs is crucial in optimizing antibiotic use. However, prescription choices can be difficult during empiric therapy; clinicians must balance the survival benefits of broader spectrum antibiotics with associated increases in resistance. The aim of this study was to evaluate the overall feasibility of switching to narrow spectrum antibiotics during the empiric treatment of E. coli bacteraemia by quantifying changes in resistance rates, antibiotic usage, and mortality using a deterministic state-transition model. Three unique model scenarios (A, B, and C), each representing a progressively broader spectrum empiric treatment regimen, were used to compare outcomes at 5 years. We show that the empiric use of the narrowest spectrum (first-line) antibiotics can lead to reductions in resistance to second-line antibiotics and the use of third-line antibiotics, but they also lead to increases in resistance to first-line therapy and higher mortality. Crucially, we find that shortening the duration of empiric and overall treatment, as well as reducing the baseline mortality rate, are important for increasing the feasibility of switching to narrow spectrum antibiotics in the empiric treatment of E. coli bacteraemia. We provide a flexible model design to investigate optimal treatment approaches for other bacterial infections.

A National Quality Improvement Collaborative to Improve Antibiotic Use in Pediatric Infections

BACKGROUND

Nearly 25% of antibiotics prescribed to children are inappropriate or unnecessary, subjecting patients to avoidable adverse medication effects and cost.

METHODS

We conducted a quality improvement initiative across 118 hospitals participating in the American Academy of Pediatrics Value in Inpatient Pediatrics Network 2020 to 2022. We aimed to increase the proportion of children receiving appropriate: (1) empirical, (2) definitive, and (3) duration of antibiotic therapy for community-acquired pneumonia, skin and soft tissue infections, and urinary tract infections to ≥85% by Jan 1, 2022. Sites reviewed encounters of children >60 days old evaluated in the emergency department or hospital. Interventions included monthly audit with feedback, educational webinars, peer coaching, order sets, and a mobile app containing site-specific, antibiogram-based treatment recommendations. Sites submitted 18 months of baseline, 2-months washout, and 10 months intervention data. We performed interrupted time series (analyses for each measure.

RESULTS

Sites reviewed 43 916 encounters (30 799 preintervention, 13 117 post). Overall median [interquartile range] adherence to empirical, definitive, and duration of antibiotic therapy was 67% [65% to 70%]; 74% [72% to 75%] and 61% [58% to 65%], respectively at baseline and was 72% [71% to 72%]; 79% [79% to 80%] and 71% [69% to 73%], respectively, during the intervention period. Interrupted time series revealed a 13% (95% confidence interval: 1% to 26%) intercept change at intervention for empirical therapy and a 1.1% (95% confidence interval: 0.4% to 1.9%) monthly increase in adherence per month for antibiotic duration above baseline rates. Balancing measures of care escalation and revisit or readmission did not increase.

CONCLUSIONS

This multisite collaborative increased appropriate antibiotic use for community-acquired pneumonia, skin and soft tissue infections, and urinary tract infection among diverse hospitals.

Relationship between Antibiotic Consumption and Resistance: A Systematic Review

Background

Unreserved use of antibiotics exerted selective pressure on susceptible bacteria, resulting in the survival of resistant strains. Despite this, the relationship between antibiotic resistance (ABR) and antibiotic consumption (ABC) is rarely studied. This systematic review aims to review the relationship between ABC and ABR from 2016 to 2022.

Methods

Articles published over 7 years (2016-2022) were searched from December 23 to 31, 2022. The search strategy was developed by using keywords for ABC and ABR. From 3367 articles, 58 eligible articles were included in the final review.

Results

The pooled ABC was 948017.9 DPDs and 4108.6 DIDs where over 70% of antibiotics were from the Watch and Reserve category based on the WHO AWaRe classification. The average pooled prevalence of ABR was 38.4%. Enterococcus faecium (59.4%), A. baumannii (52.6%), and P. aeruginosa (48.6%) were the most common antibiotic-resistant bacteria. Cephalosporins (76.8%), penicillin (58.3%), and aminoglycosides (52%) were commonly involved antibiotics in ABR. The positive correlation between ABR and consumption accounted for 311 (81%). The correlation between ABR P. aeruginosa and ABC accounted for 87 (22.7%), followed by 78 (20.3%) and 77 (20.1%) for ABR E. coli and K. pneumoniae with ABCs, respectively. Consumption of carbapenems and fluoroquinolones was most commonly correlated with resistance rates of P. aeruginosa, K. pneumoniae, E. coli, and A. baumannii.

Conclusion

There is a positive correlation between ABC and the rate of ABR. The review also revealed a cross-resistance between the consumption of different antibiotics and ABR. Optimizing antibiotic therapy and reducing unnecessary ABC will prevent the emergence and spread of ABR. Thus, advocating the implementation of stewardship programs plays a pivotal role in containing ABR.

Evaluating the relationship between ciprofloxacin prescription and non-susceptibility in Salmonella Typhi in Blantyre, Malawi: an observational study

BACKGROUND

Ciprofloxacin is the first-line drug for treating typhoid fever in many countries in Africa with a high disease burden, but the emergence of non-susceptibility poses a challenge to public health programmes. Through enhanced surveillance as part of vaccine evaluation, we investigated the occurrence and potential determinants of ciprofloxacin non-susceptibility in Blantyre, Malawi.

METHODS

We conducted systematic surveillance of typhoid fever cases and antibiotic prescription in two health centres in Blantyre, Malawi, between Oct 1, 2016, and Oct 31, 2019, as part of the STRATAA and TyVAC studies. In addition, blood cultures were taken from eligible patients presenting at Queen Elizabeth Central Hospital, Blantyre, as part of routine diagnosis. Inclusion criteria were measured or reported fever, or clinical suspicion of sepsis. Microbiologically, we identified Salmonella enterica serotype Typhi (S Typhi) isolates with a ciprofloxacin non-susceptible phenotype from blood cultures, and used whole-genome sequencing to identify drug-resistance mutations and phylogenetic relationships. We constructed generalised linear regression models to investigate associations between the number of ciprofloxacin prescriptions given per month to study participants and the proportion of S Typhi isolates with quinolone resistance-determining region (QRDR) mutations in the following month.

FINDINGS

From 46 989 blood cultures from Queen Elizabeth Central Hospital, 502 S Typhi isolates were obtained, 30 (6%) of which had either decreased ciprofloxacin susceptibility, or ciprofloxacin resistance. From 11 295 blood cultures from STRATAA and TyVAC studies, 241 microbiologically confirmed cases of typhoid fever were identified, and 198 isolates from 195 participants sequenced (mean age 12·8 years [SD 10·2], 53% female, 47% male). Between Oct 1, 2016, and Aug 31, 2019, of 177 typhoid fever cases confirmed by whole-genome sequencing, four (2%) were caused by S Typhi with QRDR mutations, compared with six (33%) of 18 cases between Sept 1 and Oct 31, 2019. This increase was associated with a preceding spike in ciprofloxacin prescriptions. Every additional prescription of ciprofloxacin given to study participants in the preceding month was associated with a 4·2% increase (95% CI 1·8-7·0) in the relative risk of isolating S Typhi with a QRDR mutation (p=0·0008). Phylogenetic analysis showed that S Typhi isolates with QRDR mutations from September and October, 2019, belonged to two distinct subclades encoding two different QRDR mutations, and were closely related (4-10 single-nucleotide polymorphisms) to susceptible S Typhi endemic to Blantyre.

INTERPRETATION

We postulate a causal relationship between increased ciprofloxacin prescriptions and an increase in fluoroquinolone non-susceptibility in S Typhi. Decreasing ciprofloxacin use by improving typhoid diagnostics, and reducing typhoid fever cases through the use of an efficacious vaccine, could help to limit the emergence of resistance.

FUNDING

Wellcome Trust, Bill & Melinda Gates Foundation, and National Institute for Health and Care Research (UK).

Treatment of Helicobacter Pylori İnfection and the Colonization of the Gastrointestinal System by Resistant Bacteria

BACKGROUND AND AIMS

Helicobacter pylori (H. pylori) infections are widely treated with antibiotic regimens such as "Amoxicillin 1 gr 2 × 1 tablet, Clarithromycin 500 mg 2 × 1 tablet, and Lansoprazole 30 mg 2 × 1 tablet" for 14 days. We conducted a prospective observational study to explore whether this treatment protocol serves as a predisposing factor for the colonization of resistant gastrointestinal microflora, namely vancomycin-resistant enterococci (VRE), extended-spectrum beta-lactamase Enterobacterales (ESBL-E), and carbapenem-resistant Enterobacterales (CRE).

MATERIALS AND METHODS

Pre- and post-treatment stool samples from 75 patients diagnosed with H. pylori, without a prior treatment history, were cultured and evaluated based on the European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria.

RESULTS

Of the 75 evaluated patients, a pronounced surge in ESBL-E positivity was observed. Before initiating antibiotic treatment, 12 patients (16%) had ESBL-E-positive strains in their gastrointestinal tract. Notably, this number surged to 24 patients (32%) after the conclusion of the 14-day treatment regimen. The change was statistically significant, with a P value of less than 0.002, indicating a clear association between treatment for H. pylori and heightened ESBL-E colonization. Notably, VRE and CRE remained undetected in patients throughout the study, suggesting that the treatment regimen may specifically amplify the risk of ESBL-E colonization without affecting VRE and CRE prevalence.

CONCLUSIONS

As the inaugural report from Turkey on this issue, our study suggests that antibiotic regimens for H. pylori eradication contribute to the increased risk of ESBL-positive bacterial colonization in the gastrointestinal tract.

Analysis of the Distribution and Drug Resistance of Pathogens in Patients with Urinary Tract Infection in the Eastern Chongming Area of Shanghai from 2018 to 2020

Purpose

The aim of this study was to clarify the distribution and drug resistance of pathogens causing urinary tract infection (UTI) and to provide a scientific reference for the rational application of antibiotics.

Patients and Methods

The results of bacterial identification and drug sensitivity analysis of midstream urine samples in our hospital from January 2018 to December 2020 were retrospectively analyzed. The data were analyzed using WHONET 5.6 and SPSS 26.0 (IBM) software.

Results

In all, 1786 pathogens were isolated from 13,141 midstream urine culture samples. Of these, 1093 (61.2%) were gram-negative bacteria, mainly Escherichia coli [29.1%] and Klebsiella pneumoniae [14.3%]; 543 (30.4%) were gram-positive bacteria, mainly Enterococcus faecium [16.7%] and Enterococcus faecalis [8.4%]; and 150 (8.4%) were fungal isolates, with the most common being Candida albicans (3.7%). The resistance rates of E. coli to piperacillin/tazobactam (3.4% vs 10.0%, p<0.05), ampicillin/sulbactam (43.0% vs 53.8%, p<0.05), and ciprofloxacin (58.0% vs 72.9%, p<0.05) increased significantly. K. pneumoniae was highly sensitive to ertapenem (100%). Two Enterococcus spp were highly sensitive to tigecycline (100%), and a small number of norvancomycin-resistant strains were found. The drug resistance rate of E. faecium to quinupristin was 6.7%. The drug resistance rates of E. faecalis to furantoin and ampicillin were 4.0% and 4.7%, respectively.

Conclusion

The pathogens that cause UTIs in patients are diverse, with the most common being E. coli. The isolated pathogens exhibited different resistance patterns. Antibiotics should be rationally selected based on the resistance patterns of the pathogens.

Risk factors for antimicrobial resistance in patients with Escherichia coli bacteraemia related to urinary tract infection

Introduction

NHS Lothian policy has recently changed to avoid first-line use of trimethoprim for uncomplicated urinary tract infections (UTI) in patients with risk factors for trimethoprim resistance, in line with national guidance. This study aimed to identify risk factors for antimicrobial resistance in Escherichia coli bacteraemia related to UTI.

Methods

A retrospective cohort study of 687 patients with E. coli bacteraemia related to UTI in NHS Lothian from 01/02/18 to 29/02/20 was undertaken. Demographics and comorbidities were collected from electronic patient records. Community prescribing and microbiology data were collected from the prescribing information system and Apex. Univariate and multivariate analysis was undertaken using RStudio to analyse trimethoprim, gentamicin and multi-drug resistance (MDR).

Results

Trimethoprim resistance was present in 282/687(41%) of blood culture isolates. MDR was present in 278/687(40.5%) isolates. Previous urinary trimethoprim resistant E. coli was a significant risk factor for both trimethoprim resistance (OR 9.44, 95%CI 5.83-15.9) and MDR (OR 4.81, 95%CI 3.17-7.43) on multivariate modelling. Trimethoprim prescription (OR 2.10, 95% CI 1.33-3.34) and the number of community antibiotic courses (OR 1.19, 95%CI 1.06-1.35) were additional risk factors for trimethoprim resistance. Multiple independent risk factors were also identified for trimethoprim resistance, MDR and gentamicin resistance.

Discussion

This study showed a high prevalence of trimethoprim resistance and MDR in patients with E. coli bacteraemia related to UTI. This supports the withdrawal of trimethoprim from first-line treatment of UTIs in patients with risk factors for trimethoprim resistance. It has also identified risk factors for MDR in E. coli bacteraemia.

Risk Factors for a Hospital-Acquired Carbapenem-Resistant Klebsiella pneumoniae Bloodstream Infection: A Five-Year Retrospective Study

Purpose

This study aimed to describe trends in Klebsiella pneumoniae (KP) resistance in bloodstream infections (BSI) and to identify risk factors for a hospital-acquired carbapenem-resistant Klebsiella pneumoniae (CRKP) BSI and 28-day mortality from a hospital-acquired KP BSI.

Patients and Methods

We recorded the results of antimicrobial susceptibility testing of 396 KP-positive blood cultures from January 2016 to December 2020. A total of 277 patients with a KP BSI were included in this study, of which 171 had a hospital-acquired infection and 84 had a hospital-acquired CRKP BSI. Multivariate logistic regression analysis was used to identify risk factors for a hospital-acquired CRKP BSI and 28-day mortality from a hospital-acquired KP BSI.

Results

The proportion of hospital-acquired infections among KP BSI patients increased from 53.1% in 2016 to 72.8% in 2020. The detection rate of CRKP among KP BSI patients increased from 18.8% in 2016 to 37.7% in 2020. Multivariate logistic regression showed that β-lactam/β-lactamase inhibitor combinations (BLBLIs) exposure (P  = 0.022, OR 2.863), carbapenems exposure (P  = 0.007, OR 3.831) and solid organ transplantation (P   <0.001, OR 19.454) were independent risk factors for a hospital-acquired CRKP BSI. Risk factors for a 28-day mortality from hospital-acquired KP BSI were CRKP BSI (P  =0.009, OR 5.562), septic shock (P  =0.002, OR 4.862), mechanical ventilation>96 hours (P =0.020, OR 8.765), and platelet counts <100×10⁹/L (P  =0.003, OR 4.464).

Conclusion

The incidence of hospital-acquired KP BSI continues to rise and the proportion of CRKP BSI is also increasing. We believe that the use of the BLBLIs needs to be carefully evaluated in hospital-acquired infection. Hospital-acquired KP BSI Patients with CRKP BSI, septic shock, mechanical ventilation and deficiency of platelets are more likely to have a poor prognosis.

Temporal and structural patterns of extended-spectrum cephalosporin-resistant Klebsiella pneumoniae incidence in Swiss hospitals

BACKGROUND

Routine surveillance data revealed increasing rates of invasive extended-spectrum cephalosporin-resistant Klebsiella pneumoniae (ESCR-KP) in Switzerland, from 1.3% in 2004 to 8.5% in 2019.

AIM

The main aim of this study was to understand the causes of this recent trend, specifically to identify predictors affecting the incidence of invasive ESCR-KP infections in Switzerland.

METHODS

A retrospective observational multi-centre study was conducted in 21 Swiss hospitals over a period of 11 years (2009-2019). Potential predictor variables for the incidence of invasive ESCR-KP infections were studied with a multiple linear regression model. In an additional analysis, the overall ESCR-KP incidence (all sample sites) was investigated.

FINDINGS

An increasing incidence of invasive ESCR-KP infections from 0.01 to 0.04 patients per 1000 bed-days was observed between 2009 and 2019 and confirmed by multiple linear regression analysis (P < 0.01). ESCR-KP incidence was higher in university hospitals (P < 0.01) and in the French-speaking region than in the German-speaking region (P < 0.01). There was no association with antibiotic consumption. Analysing the overall ESCR-KP incidence (all sample sites) revealed high variability between university hospitals, mainly due to a high proportion of patients with screening isolates at Geneva University Hospital (50% of patients with ESCR-KP).

CONCLUSION

The incidence of invasive ESCR-KP infections increased in Switzerland between 2009 and 2019 and was not associated with antibiotic consumption. Our findings indicate that, in this low-incidence setting, structural factors such as the hospital type and the linguistic region play a more important role in relation to ESCR-KP incidence than the hospital's antibiotic consumption.

[Use of antimicrobials in acute canine diarrhea - overview of potential risks, indications and alternatives]

In Germany, antibiotics are frequently used in dogs with gastrointestinal disorders such as acute diarrhea. In line with global efforts to limit antibiotic use, this literature review aims to provide a guideline for the rational and judicious use of antibiotics in acute canine diarrhea. Antibiotics can lead to gastrointestinal side effects and may exert a negative influence on the intestinal microbiota in addition to increasing the occurrence of resistant bacteria. There is also evidence that chronic immunological diseases may be triggered by the administration of antibiotics. Therefore, these should not be administered in uncomplicated acute diarrhea without signs of sepsis or systemic inflammatory reaction. In addition, enteropathogenic bacteria usually do not play a role in the etiology of acute diarrhea. For select clinical entities such as acute hemorrhagic diarrhea syndrome, antibiotic therapy should only be recommended in cases displaying signs of bacterial translocation with subsequent sepsis. In the case of parvovirosis, on the other hand, the administration of antibiotics is unavoidable due to the immunological incompetence of the dog caused by the accompanying severe neutropenia.

Antibiotic exposure in hospitalized pediatric patients in the United States: prevalence and length of stay

BACKGROUND

Hospital antibiotic use is rising. We aimed to evaluate the antibiotic-use prevalence and length of stay.

METHODS

We conducted a single-center retrospective study of patients < 18-years-old admitted to general pediatric services who received ≥ 1 antibiotic over six months. Demographics, culture results and antibiotic details were collected. The primary outcome was to identify the total number and classes of antibiotics prescribed during the admission. Secondary outcomes included length of stay (LOS), culture results, and the most commonly used antibiotics.

RESULTS

Forty-eight percent of patients received monotherapy (single class antibiotic). Cephalosporins (55%), vancomycin (35%), and clindamycin (22%) were prescribed more commonly than other antibiotic classes. Children were exposed up to 4 classes of antibiotics (range 1-4). A moderate correlation existed between the length of stay and the number of antibiotic classes used (R² = 0.38). Two or more classes of antibiotic use prolonged the length of stay. Cephalosporin use was associated with 35% reduced LOS (95 CI, 21%-57%), and penicillin use correlated with 38% more prolonged LOS (95 CI, 22%-66%).

CONCLUSIONS

Antibiotic use in pediatric hospitals was high, and children received multiple classes of antibiotics. Inappropriate antibiotic use and culture results may have an untoward effect on hospital length of stay.

Antibiotic Consumption in Hospitals and Resistance Rate of Klebsiella pneumoniae and Escherichia coli in Montenegro

Inappropriate use of antibiotics leads to an increase in antibiotic resistance. Infections caused by antibiotic-resistant gram-negative bacteria are a serious threat to public health. This study aimed to compare data on inpatient antibiotic consumption with antimicrobial resistance (AMR) rate of Klebsiella pneumoniae and Escherichia coli invasive strains in Montenegro and provide targets for improving antibiotic use. We used the national data on antibiotic consumption from 2009 to 2015, Point Prevalence Survey data on inpatient antibiotic consumption from 2015, and national AMR data on 79 Klebsiella pneumoniae and 68 Escherichia coli isolates collected from 8 hospitals from 2016 to 2018. The most commonly used antibiotics were third-generation cephalosporins with a median annual consumption of 0.66 DDD/1000/day. Ceftriaxone was the most frequently prescribed antibiotic in the treatment of community/hospital acquired infections and surgical/medical prophylaxis. The highest resistance rates were recorded for Klebsiella pneumoniae to ceftriaxone, ceftazidime and gentamicin (93.59%, 90.79% and 89.87%, respectively), and Escherichia coli to aminopenicillins, ceftriaxone and ceftazidime (89.06%, 70.15% and 61.54%, respectively). High consumption of broad-spectrum antibiotics in Montenegro is accompanied by the high rate of resistance of Klebsiella pneumoniae and Escherichia coli to these agents. Antibiotic misuse demands the introduction of an antimicrobial stewardship program in Montenegrin hospitals.

Utilization of cumulative antibiograms for public health surveillance: Trends in Escherichia coli and Klebsiella pneumoniae susceptibility, Massachusetts, 2008-2018

BACKGROUND

Antimicrobial resistance is an urgent public health threat. Identifying trends in antimicrobial susceptibility can inform public health policy at the state and local levels.

OBJECTIVE

To determine the ability of statewide antibiogram aggregation for public health surveillance to identify changes in antimicrobial resistance trends.

DESIGN

Facility-level trend analysis.

METHODS

Crude and adjusted trend analyses of the susceptibility of Escherichia coli and Klebsiella pneumoniae to particular antibiotics, as reported by aggregated antibiograms, were examined from 2008 through 2018. Multivariable regression analyses via generalized linear mixed models were used to examine associations between hospital characteristics and trends of E. coli and K. pneumoniae susceptibility to ciprofloxacin and ceftriaxone.

RESULTS

E. coli and K. pneumoniae showed inverse trends in drug susceptibility over time. K. pneumoniae susceptibility to fluoroquinolones increased by 5% between 2008 and 2018 (P < .05). In contrast, E. coli susceptibility declined during the same period to ceftriaxone (6%), gentamicin (4%), and fluoroquinolones (4%) (P < .05). When compared to Boston hospitals, E. coli isolates from hospitals in other regions had a >4% higher proportion of susceptibility to ciprofloxacin and a >3% higher proportion of susceptibility to ceftriaxone (P < .05). Isolates of K. pneumoniae had higher susceptibility to ciprofloxacin (>3%) and ceftriaxone (>1.5%) in all regions when compared to Boston hospitals (P < .05).

CONCLUSIONS

Cumulative antibiograms can be used to monitor antimicrobial resistance, to discern regional and facility differences, and to detect changes in trends. Furthermore, because the number of years that hospitals contributed reports to the state-level aggregate had no significant influence on susceptibility trends, other states should not be discouraged by incomplete hospital compliance.

Association between the rate of fluoroquinolones-resistant gram-negative bacteria and antibiotic consumption from China based on 145 tertiary hospitals data in 2014

Background

The purpose of the study is to discuss the correlation between the resistance rate of gram negative bacteria to fluoroquinolones (FQ) and antibiotic consumption intensity of 145 China tertiary hospitals in 2014.

Methods

This retrospective study adopted national monitoring data from 2014. Each participating hospital required to report annual consumption of each antibiotic, and the resistance rate of gram negative bacteria to FQ. Then the correlation between antibiotic usage and fluoroquinolones –resistant (FQR) rate was consequently investigated.

Results

One hundred forty-five hospitals were included in the study, and the median antibiotic consumption intensity was 46.30 (23.93–115.39) defined daily dosages (DDDs) per 100 patient-days. Cephalosporins ranks first in the antibiotics consumption, followed by fluoroquinolones, penicillins, and carbapenems. Fluoroquinolones resistance rate varied from hospital to hospital. The correlation analysis showed significant relationship between the percentage of FQR Escherichia coli and the consumption of FQs (r = 0.308, p<0.01) and levofloxacin (r = 0.252, p<0.01). For FQR Klebsiella pneumoniae, not only FQs (r = 0.291, p<0.01) and levofloxacin (r = 0.260, p<0.01) use but also carbapenems (r = 0.242, p<0.01) and overall antibiotics (r = 0.247, p<0.01) use showed significant correlation. The resistant proportion of FQR Pseudomonas aeruginosa was observed to be correlated with the consumption of all antibiotics (r = 0.260, p<0.01), FQs (r = 0.319, p<0.01) and levofloxacin (r = 0.377, p<0.01). The percentage of levofloxacin-resistant Acinetobacter baumannii was significantly correlated with the consumption of all antibiotics (r = 0.282, p<0.01), third-generation cephalosporins excluding combinations with beta-lactamase inhibitors (r = 0.246, p<0.01), FQs (r = 0.254, p<0.01) and levofloxacin (r = 0.336, p<0.01). However, the correlation of the ciprofloxacin-resistant A. baumannii and the antibiotics consumption was not found.

Conclusions

A strong correlation was demonstrated between the antibiotic consumption and the rates of FQR gram-negative bacteria. As unreasonable antibiotics usage remains crucial in the proceeding of resistant bacteria selection, our study could greatly promote the avoidance of unnecessary antibiotic usage.

Impact of antimicrobial stewardship managed by clinical pharmacists on antibiotic use and drug resistance in a Chinese hospital, 2010-2016: a retrospective observational study

OBJECTIVES

'National Special Stewardship in the Clinical Use of Antibiotics' was put forward in July 2011 in China. We aimed to retrospectively evaluate the impact of antimicrobial stewardship (AMS) managed by clinical pharmacists on antibiotic utilisation, prophylaxis and antimicrobial resistance (AMR).

DESIGN

This was a retrospective observational study of trends in antibiotic use and AMR in the context of AMS.

SETTING

Beijing Chaoyang Hospital, a 1400-bed tertiary hospital, in China.

DATA AND PARTICIPANTS

Antibiotic prescriptions from 820 doctors included all outpatients (n=17 766 637) and inpatients (n=376 627) during 2010-2016. Bacterial resistance data were from all inpatients (n=350 699) during 2011-2016.

INTERVENTIONS

Multiaspect intervention measures were implemented by clinical pharmacists (13 persons), for example, formulating the activity programme and performance management, advising on antibacterial prescriptions and training.

OUTCOME MEASURES

The proportion of antibiotic prescriptions among outpatients and inpatients, intensity of consumption in defined daily dose (DDD)/100 bed-days, antibiotic prophylaxis in type I incision operations and resistance rates of Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa were retrospectively analysed.

RESULTS

The proportion of antibiotic prescriptions decreased in outpatients (from 19.38% to 13.21%) and in inpatients (from 64.34% to 34.65%), the intensity of consumption dropped from 102.46 to 37.38 DDD/100 bed-days. The proportion of antibiotic prophylaxis decreased from 98.94% to 18.93%. The proportion of rational timing of initial dose increased from 71.11% to 96.74%, the proportion of rational duration rose from 2.84% to 42.63%. Time series analysis demonstrated the resistance rates of E. coli and P. aeruginosa to fluoroquinolones decreased, the incidence rate of methicillin-resistant Staphylococcus aureus also decreased, whereas the resistance rates of E. coli and K. pneumoniae to carbapenems increased. The antibiotic use was partly positively correlated with AMR.

CONCLUSIONS

AMS had an important role in reducing antibiotic use and surgical antibiotic prophylaxis. The AMR was positively correlated with antibiotic consumption to some extent.