Nationwide surveillance of antimicrobial consumption and resistance to Pseudomonas aeruginosa isolates at 203 Japanese hospitals in 2010

Efficacy of cefmetazole in immunocompetent patients with uncomplicated colonic diverticulitis: A propensity score matching analysis

INTRODUCTION

The incidence of colonic diverticulitis is increasing in Japan. Although antimicrobial chemotherapy is a treatment option, Japanese guidelines for diverticulosis do not recommend any antibiotic in particular and antibiotic selection is left to the discretion of the prescribing physician, who often selects antibiotics with anti-pseudomonal activity. Therefore, this study compared the efficacy of cefmetazole (CMZ) with that of tazobactam/piperacillin (TAZ/PIPC) in hospitalized Japanese immunocompetent patients with uncomplicated colonic diverticulitis.

PATIENTS AND METHODS

This retrospective study included Japanese immunocompetent patients hospitalized for colonic diverticulitis between April 2019 and March 2022. Participants were divided into the CMZ and TAZ/PIPC groups. After propensity score matching, the intergroup differences in clinical outcomes, including adverse events, mortality, and re-admission rate, were ascertained.

RESULTS

During the study period, 142 Japanese patients were hospitalized with community-onset colonic diverticulitis; 124 of these patients were immunocompetent. Of the 124 patients, 42 were excluded, and the CMZ and TAZ/PIPC groups comprised 62 and 20 patients, respectively. After propensity score matching, there were 16 patients in each group. There was no significant intergroup difference in the mortality and re-admission rates; however, the incidence of liver dysfunction was significantly higher (p = 0.018) in the TAZ/PIPC group.

CONCLUSION

In patients with colonic diverticulitis, CMZ therapy should be selected because of the adequate clinical outcomes and lower incidence of adverse events, as this would reduce broad-spectrum antibiotic use and minimize antibiotic-resistant bacteria.

Inactivation of antibiotic-resistant bacteria in hospital wastewater by ozone-based advanced water treatment processes

The emergence and spread of antimicrobial resistance (AMR) continue on a global scale. The impacts of wastewater on the environment and human health have been identified, and understanding the environmental impacts of hospital wastewater and exploring appropriate forms of treatment are major societal challenges. In the present research, we evaluated the efficacy of ozone (O3)-based advanced wastewater treatment systems (O3, O3/H2O2, O3/UV, and O3/UV/H2O2) for the treatment of antimicrobials, antimicrobial-resistant bacteria (AMRB), and antimicrobial resistance genes (AMRGs) in wastewater from medical facilities. Our results indicated that the O3-based advanced wastewater treatment inactivated multiple antimicrobials (>99.9%) and AMRB after 10-30 min of treatment. Additionally, AMRGs were effectively removed (1.4-6.6 log10) during hospital wastewater treatment. The inactivation and/or removal performances of these pollutants through the O3/UV and O3/UV/H2O2 treatments were significantly (P < 0.05) better than those in the O3 and O3/H2O2 treatments. Altered taxonomic diversity of microorganisms based on 16S rRNA gene sequencing following the O3-based treatment showed that advanced wastewater treatments not only removed viable bacteria but also removed genes constituting microorganisms in the wastewater. Consequently, the objective of this study was to apply advanced wastewater treatments to treat wastewater, mitigate environmental pollution, and alleviate potential threats to environmental and human health associated with AMR. Our findings will contribute to enhancing the effectiveness of advanced wastewater treatment systems through on-site application, not only in wastewater treatment plants (WWTPs) but also in medical facilities. Moreover, our results will help reduce the discharge of AMRB and AMRGs into rivers and maintain the safety of aquatic environments.

Healthcare-associated infections by multidrug-resistant bacteria in Andalusia, Spain, 2014 to 2021

BackgroundMultidrug-resistant (MDR) bacteria are among chief causes of healthcare-associated infections (HAIs). In Spain, studies addressing multidrug resistance based on epidemiological surveillance systems are lacking.AimIn this observational study, cases of HAIs by MDR bacteria notified to the epidemiological surveillance system of Andalusia, Spain, between 2014-2021, were investigated. Notified cases and their spatiotemporal distribution were described, with a focus on social determinants of health (SDoH).MethodsNew cases during the study period of HAIs caused by extended-spectrum β-lactamase (ESBL)-/carbapenemase-producing Enterobacterales, MDR Acinectobacter baumannii, MDR Pseudomonas aeruginosa or meticillin resistant Staphylococcus aureus were considered. Among others, notification variables included sex and age, while socio-economic variables comprised several SDoH. Cases' spatial distribution across municipalities was assessed. The smooth standardised incidence ratio (sSIR) was obtained using a Bayesian spatial model. Association between municipalities' sSIR level and SDoH was evaluated by bivariate analysis.ResultsIn total, 6,389 cases with a median age of 68 years were notified; 61.4% were men (n = 3,921). The most frequent MDR bacteria were ESBL-producing Enterobacterales (2,812/6,389; 44.0%); the main agent was Klebsiella spp. (2,956/6,389; 46.3%). Between 2014 and 2021 case numbers appeared to increase. Overall, up to 15-fold differences in sSIR between municipalities were observed. In bivariate analysis, there appeared to be an association between municipalities' sSIR level and deprivation (p = 0.003).ConclusionThis study indicates that social factors should be considered when investigating HAIs by MDR bacteria. The case incidence heterogeneity between Andalusian municipalities might be explained by SDoH, but also possibly by under-notification. Automatising reporting may address the latter.

An Overview of Antimicrobial Resistance in Saudi Arabia (2013-2023) and the Need for National Surveillance

Antimicrobial resistance (AMR) is a well-recognized global threat. The World Health Organization (WHO) issued a report ranking the critical types of bacterial resistance that need to be monitored. Several studies from individual institutions in Saudi Arabia have reported rates of antimicrobial resistance using automated methods. However, no national surveillance study has been conducted to date using gold standard methods for antimicrobial susceptibility testing. This review summarizes AMR rates for major bacterial pathogens in Saudi Arabia and provides a justification for the need for a national surveillance project. In Saudi Arabia, AMR rates for both Gram-positive and Gram-negative bacteria are on the rise. Surveillance studies help identify AMR trends and emergence of outbreaks. The WHO has started a program, the Global Antimicrobial Resistance Surveillance System (GLASS), encouraging its member states, including Saudi Arabia, to conduct antimicrobial surveillance studies to estimate AMR rates worldwide. Of the microbiological methods used to test antimicrobial susceptibility, only broth microdilution (BMD) is considered the "gold standard." As AMR studies in Saudi Arabia are sparse, mostly limited to single centers and were conducted using automated methods, a national AMR surveillance project is needed to evaluate the current status and to inform stewardship decisions.

Influence of Change of Full-Time Equivalents on Post-prescription Review with Feedback Interventions in an Antimicrobial Stewardship

Few studies have investigated the influence of more full-time equivalents (FTEs) of infectious disease (ID) pharmacists on the likelihood of a post-prescription review with feedback (PPRF) intervention. This study focused on this in community hospitals before and after the Japanese medical reimbursement system was revised to introduce antimicrobial stewardship (AS) fees. We collected data for two periods: before (April 2017 to March 2018) and after (April 2018 to March 2019) AS fee implementation. The efficacy of the PPRF by the ID pharmacist was assessed based on the usage of broad-spectrum antimicrobials in days of therapy (DOT) per 100 patient-days. Further, we generated the susceptibility rate for antimicrobial-resistant organisms. The number of PPRF drugs was 2336 (2596 cases) before AS fee implementation and 2136 (1912 cases) after implementation. The overall monthly FTE for AS for an ID pharmacist increased from [median (interquartile range; IQR)] 0.34 (0.33-0.36) to 0.63 (0.61-0.63) after AS fee implementation. The DOT of the broad-spectrum antibiotics decreased from 10.46 (9.61-12.48) to 8.68 (8.14-9.18). The DOT of carbapenems and quinolones decreased significantly from 4.11 (3.69-4.41) to 3.07 (2.79-3.22) and 0.96 (0.61-1.14) to 0.37 (0.19-0.46), respectively (p < 0.05). Furthermore, the rate of levofloxacin (LVFX)-susceptible Pseudomonas (P.) aeruginosa improved from 71.5 to 84.8% (p < 0.01). We observed that increasing the FTE of ID pharmacists influences the DOTs of broad-spectrum antibiotics; a higher FTE contributes to fewer DOTs. Further, the susceptibility of P. aeruginosa to meropenem and LVFX increased as the FTE increased.

Regional antimicrobial stewardship program in a provincial medical zone in Japan: A multifaceted approach

Antimicrobial resistance (AMR) is a threat to patient health. However, there is a lack of data for optimizing antimicrobial use. Furthermore, reducing antibiotic use raises concerns regarding patient safety; there is controversy regarding its effectiveness in reducing AMR prevalence. Researchers at the Japanese Red Cross Ishinomaki Hospital (JRCIH), the only tertiary care hospital in the medical zone, along with local medical and pharmacy associations and public health centers, has been leading the AMR control program since 2018. The program involves lectures aimed at optimizing antimicrobial use, regular publication of surveillance data of drug-resistant strains at the JRCIH, and presentation of first-line treatments for community-acquired infections. Delivery of oral antimicrobials across the region in 2020 was 28.7% lower than that in 2013, with delivery of cephalosporins, quinolones, and macrolides dropping by 34.8%, 46.8%, and 56.0%, respectively. Despite these reductions, there has been no associated increase in the number of patients with severe infectious diseases admitted to the JRCIH. The rates of representative drug-resistant strains bacteremia, such as extended-spectrum beta-lactamase-producing Escherichia coli and methicillin-resistant Staphylococcus aureus, reduced by half. Herein, we demonstrated the potential of collaborative efforts to optimize antimicrobial agent use and reduce AMR prevalence without compromising patient safety.

Antibiotic use in Brazilian hospitals in the 21st century: a systematic review

INTRODUCTION

This systematic review aimed to assess antibiotic use in Brazilian hospitals in the 21st century, as well as to understand the different drug utilization metrics adopted to assess the consumption of these drugs.

METHODS

We systematically reviewed five databases (MEDLINE [Medical Literature Analysis and Retrieval System Online], CENTRAL [The Cochrane Central Register of Controlled Trials], EMBASE® [Excerpta Medica Database], Scopus [Elsevier's abstract and citation database], and LILACS [Literatura Latino-Americana e do Caribe em Ciências da Saúde]) for observational or experimental studies that assessed antibiotic utilization in Brazilian hospitals. The main outcomes were the drug utilization metrics and the consumption of antibiotics.

RESULTS

We included 23 studies, of which 43.5% were carried out in adult and pediatric care units, 39.1% in adult units, and 17.4% in pediatric units. Regarding the complexity of healthcare, 26.1% of the studies were performed in intensive care units. Two drug utilization metrics were used in these studies: the defined daily dose (DDD) and the percentage of antibiotic prescriptions. The most commonly used antibiotic classes were third-generation cephalosporins, carbapenems, fluoroquinolones, and combinations of penicillins when the DDD was the adopted drug utilization metric.

CONCLUSIONS

Although few studies have been conducted, existing data indicate a high use of broad-spectrum antibiotics. We found that the lack of standardized antibiotic utilization metrics impaired the mapping of drug consumption at the national level.

Trends in Antipseudomonal Agent Use Based on the 2006 to 2015 Sales Data in Japan

Pseudomonas aeruginosa resistance is a major issue worldwide. Drug resistance is related to inappropriate antibiotic use. Because antipseudomonal agents have a wide spectrum, they must be used appropriately. The purpose of this study was to clarify the trends in antipseudomonal agent use in Japan based on sales data from 2006 to 2015. The total antipseudomonal agent use was increased significantly (r = 0.10, P_{for trend} = 0.00040). The proportion of fluoroquinolones use was the highest throughout the year, accounting for 88.6-91.4%. The use of piperacillin/tazobactam significantly increased. The increased use of these drugs may be due to the launch of higher doses and additional indications. On the other hand, for antipseudomonal agents, parenteral carbapenems use was 2.7-3.7%, but it has remained unchanged over the years. In Japan, permit and notification systems have been introduced to prevent the inappropriate use of parenteral carbapenems in medical institutions. It was speculated that these efforts suppressed the inappropriate use of parenteral carbapenems. This study clarified the trend of antipseudomonal agent use in Japan from 2006 to 2015. It is important to continue monitoring antipseudomonal agents use to conduct appropriate antimicrobial resistance measures.

Antibiotic consumption study in two hospitals in Asmara from 2014 to 2018 using WHO's defined daily dose (DDD) methodology

This study compares the antibiotic consumption rates over a period of five years in two hospitals in Eritrea, Orotta National Referral and Teaching Hospital (ONRTH) and Hazhaz Zonal Referral Hospital (HZRH). Antibiotic consumption is an important parameter in the study of antibiotic use. However, no published data on consumption rates exist for these two hospitals, thus the aim of the study is to measure and compare a five year antibiotic consumption trends of the two hospitals' medical wards using Defined Daily Dose per 100 bed-days (DDD/100-BD). Antibiotics dispensed from January 2014 to December 2018 were considered. Non-parametric Pearson's correlation coefficient was used for comparison of consumption, while non-parametric Friedman's test measured annual rates. The total antibiotic consumption in the HZRH was almost double that of ONRTH. The analysis showed that antibiotic consumption in ONRTH was significantly decreased from 2014 to 2018 while there was no significant difference in consumption in HZRH. Benzyl penicillin was the most consumed antibiotic in HZRH and ONRTH throughout the study period at 87.8DDD/100-BD and 35.4 DDD/100-BD respectively. Ceftriaxone and ciprofloxacin were among the most commonly consumed antibiotics in both hospitals. Establishment of Antibiotic stewardship program would benefit both hospitals greatly, and further studies need to be done to establish the national antibiotic consumption baseline.

Phenazines as potential biomarkers of Pseudomonas aeruginosa infections: synthesis regulation, pathogenesis and analytical methods for their detection

Infectious diseases are still a worldwide important problem. This fact has led to the characterization of new biomarkers that would allow an early, fast and reliable diagnostic and targeted therapy. In this context, Pseudomonas aeruginosa can be considered one of the most threatening pathogens since it causes a wide range of infections, mainly in patients that suffer other diseases. Antibiotic treatment is not trivial given the incidence of resistance processes and the fewer new antibiotics that are placed on the market. With this scenario, relevant quorum sensing (QS) molecules that regulate the secretion of virulence factors and biofilm formation can play an important role in diagnostic and therapeutic issues. In this review, we have focused our attention on phenazines, as possible new biomarkers. They are pigmented metabolites that are produced by diverse bacteria, characterized for presenting unique redox properties. Phenazines are involved in virulence, competitive fitness and are an essential component of the bacterial QS system. Here we describe their role in bacterial pathogenesis and we revise phenazine production regulation systems. We also discuss phenazine levels previously reported in bacterial isolates and in clinical samples to evaluate them as putative good candidates to be used as P. aeruginosa infection biomarkers. Moreover we deeply go through all analytical techniques that have been used for their detection and also new approaches are discussed from a critical point. Graphical abstract.

Impact of an antimicrobial stewardship program in the antimicrobial-resistant and prevalence of clostridioides difficile infection and amount of antimicrobial consumed in cancer patients

OBJECTIVE

The The impact of a hospital antimicrobial stewardship was determined on antimicrobial-resistant, Clostridioides difficile rates and the amount of antimicrobial consumed in cancer patients.The intervention effects of antimicrobial stewardship (ASP) plans in 2017-2018 and 2018-2019 were respectively evaluated among hematology/oncology and bone marrow transplant patients in Ayatollah Taleghani University Hospital, Tehran, Iran. In this interventional quasi-experimental study, the ASP repository was utilized to capture four survey questions encompassed in these immunocompromised patients: amount of antibiotics (meropenem and vancomycin) consumption gr-year, the number of positive Clostridioides difficile infection and multidrug-resistant positive cases in blood cultures.

RESULTS

The number of MDR cases in the periods of 2017-2018 and 2018-2019 were 145 and 75, respectively (p = 0.011). A significant reduction in all positive blood cultures from 2017-2018 to 2018-2019 was found (p = 0.001). 574 patients admitted to our hospital in these periods of 2017- 2018 and 2018- 2019were assessed for MPM and VMN use. The amounts of MPM prescriptions in 2018-2019 was significantly decreased from 22464 to 17262 g (p = 0.043). The significant reduction in antibiotic consumption, MDR organisms, and CDI can highly promote patients' health and decreasing medical costs and long-term defects for patients.

Increased financial burdens and lengths of stay in patients with healthcare-associated infections due to multidrug-resistant bacteria in intensive care units: A propensity-matched case-control study

Background and objectives

Incidence rates of healthcare-associated infections (HAIs) depend upon infection control policy and practices, and the effectiveness of the implementation of antibiotic stewardship. Amongst intensive care unit (ICU) patients with HAIs, a substantial number of pathogens were reported to be multidrug-resistant bacteria (MDRB). However, impacts of ICU HAIs due to MDRB (MDRB-HAIs) remain understudied. Our study aimed to evaluate the negative impacts of MRDB-HAIs versus HAIs due to non-MDRB (non-MRDB-HAIs).

Methods

Among 60,317 adult patients admitted at ICUs of a 2680-bed medical centre in Taiwan between January 2010 and December 2017, 279 pairs of propensity-score matched MRDB-HAI and non-MRDB-HAI were analyzed.

Principal findings

Between the MDRB-HAI group and the non-MDRB-HAI group, significant differences were found in overall hospital costs, costs of medical and nursing services, medication, and rooms/beds, and in ICU length-of-stay (LOS). As compared with the non-MDRB-HAI group, the mean of the overall hospital costs of patients in the MDRB-HAI group was increased by 26%; for categorized expenditures, the mean of costs of medical and nursing services of patients in the MDRB-HAI group was increased by 8%, of medication by 26.9%, of rooms/beds by 10.3%. The mean ICU LOS in the MDRB-HAI group was increased by 13%. Mortality rates in both groups did not significantly differ.

Conclusions

These data clearly demonstrate more negative impacts of MDRB-HAIs in ICUs. The quantified financial burdens will be helpful for hospital/government policymakers in allocating resources to mitigate MDRB-HAIs in ICUs; in case of need for clarification/verification of the medico-economic burdens of MDRB-HAIs in different healthcare systems, this study provides a model to facilitate the evaluations.

Endogenous endophthalmitis caused by group B streptococcus; case reports and review of 35 reported cases

Background

Group B streptococcus (GBS), a gram-positive coccus that occasionally causes neonatal sepsis or invasive infection in the elderly, has been considered a rare cause of endogenous bacterial endophthalmitis (EBE). However, the number of invasive GBS infections is increasing, particularly in elderly patients with underlying conditions such as diabetes mellitus (DM), cardiovascular disease and cancer. We report 6 cases of EBE caused by GBS and review the literature.

Methods

Retrospective case series and literature review.

Results

In the current case series, 6 eyes of 6 patients developed EBE caused by GBS. The average age was 73.5 years. The focus of infection included the urinary tract, cellulitis, arthritis, peritonitis, catheter-associated infection and endocarditis. Four patients had DM. While all 6 strains were sensitive to β-lactams (penicillins and cephems), 4 strains were resistant to levofloxacin (no data for 1 isolate). Each case was treated with the systemic antibiotic to which the individual strain was sensitive. All cases showed poor visual acuity at presentation (decimal visual acuity: less than 0.03). Vitrectomy with intravitreal antibiotics injection was performed in 4 cases. Visual acuity recovered in 4 cases and did not recover in 2 cases, even after vitrectomy. The literature review of 53 eyes of 41 patients revealed that 60% of eyes finally lost all vision, and death occurred in 2 cases. Initial visual acuity of less than counting fingers was associated with a final outcome of lost vision. Of 41 patients, 13 (32%) had DM as an underlying medical condition. The most common extra-ocular infection focus was endocarditis (37%).

Conclusions

DM is common in patients with EBE caused by GBS. While the 4 cases in the current report had a relatively good visual acuity outcome, despite poor initial visual acuity, the literature review indicated that EBE caused by GBS is generally a severe condition with a poor prognosis. The current study also indicates the importance of considering the possibility of endocarditis on encountering EBE caused by GBS.

Development of the predicted and standardized carbapenem usage metric: Analysis of the Japanese Diagnosis Procedure Combination payment system data

This study aimed to develop a metric for standardized and predicted carbapenem consumption using the Diagnosis Procedure Combination payment system database and patients' characteristics. Based on Diagnosis Procedure Combination data analysis, the developed metric will provide useful benchmarks that stewardship programs can use to help drive improvements.

Epidemiology of Antimicrobial Use among Nursing Homes in Japan, 2016: a Pilot Study

Antimicrobial resistance is an emerging problem in both acute care hospitals and nursing homes. From January to December 2016, we conducted a pilot, descriptive epidemiological study to examine antimicrobial use (AMU) among 6 nursing homes in Tokyo, Japan. AMU was extracted from prescription data of a pharmacy that received all prescriptions from the 6 nursing homes. To standardize the comparison of drug usage, AMU was measured using the defined daily dose (DDD) and estimated as DDDs/1,000 resident-days. The overall AMU was 15.3/1,000 resident-days, including oral antimicrobials (15.2/1,000 resident-days [99.3%]). The most frequently prescribed oral-antimicrobials was macrolides (5.8/1,000 resident-days [38.2%]) and quinolones (4.2/1,000 resident-days [27.6%]). Oral macrolides and quinolones were thought to be a convenience in prescription among nursing homes with resource limiting due to smaller defined the number of daily doses compared to penicillins and cephalosporins. In addition, multicenter studies that include resident-specific data (demographics and diagnosis) and focus on the purpose of antimicrobials (treatment or prevention) are needed to evaluate the appropriateness of antimicrobials.

Accelerating reductions in antimicrobial resistance: Evaluating the effectiveness of an intervention program implemented by an infectious disease consultant

OBJECTIVES

Very few infectious disease physicians exist in Japan. A concerted infection control intervention program involving an antimicrobial stewardship team and multiple components was designed and implemented in multiple hospitals from 2010. Here, we aimed to retrospectively evaluate the intervention program's effectiveness.

METHODS

The frequencies of methicillin resistant Staphylococcus aureus (MRSA) and drug-resistant Pseudomonas aeruginosa were monitored in four acute-care hospitals. The primary goal of the program was to accelerate the speed of decline of such resistance. A quasi-experimental study design was used to detect accelerated rates of increases in drug susceptibility, comparing time before and after the intervention.

RESULTS

Both MRSA and drug-resistant P. aeruginosa exhibited decreasing trends (p < 0.01 for all four hospitals and all bacterial cultures). Compared with the whole of Japan, the decreasing trends for MRSA and drug-resistant P. aeruginosa in the four hospitals accelerated after the intervention program was established; notably, the rate of MRSA decrease increased by 50%-150% of its original value.

CONCLUSIONS

The intervention program successfully reduced the proportion of drug resistance in the four hospitals. Centering on systematic education, decision-making support, and implementation and oversight by an infectious disease consultant, this program was shown to be effective where specialist physicians are scarce.

Changes of resistance rates in Pseudomonas aeruginosa strains are unrelated to antimicrobial consumption in ICU populations with invasive device-related infection

OBJECTIVE

To evaluate the relationship between antipseudomonal antibiotic consumption and each individual drug resistance rate in Pseudomonas aeruginosa strains causing ICU acquired invasive device-related infections (IDRI).

DESIGN

A post hoc analysis was made of the data collected prospectively from the ENVIN-HELICS registry.

SETTING

Intensive Care Units participating in the ENVIN-UCI registry between the years 2007 and 2016 (3-month registry each year).

PATIENTS

Patients admitted for over 24h.

MAIN VARIABLES

Annual linear and nonlinear trends of resistance rates of P. aeruginosa strains identified in IDRI and days of treatment of each antipseudomonal antibiotic family per 1000 occupied ICU bed days (DOT) were calculated.

RESULTS

A total of 15,095 episodes of IDRI were diagnosed in 11,652 patients (6.2% out of a total of 187,100). Pseudomonas aeruginosa was identified in 2095 (13.6%) of 15,432 pathogens causing IDRI. Resistance increased significantly over the study period for piperacillin-tazobactam (P<0.001), imipenem (P=0.016), meropenem (P=0.004), ceftazidime (P=0.005) and cefepime (P=0.015), while variations in resistance rates for amikacin, ciprofloxacin, levofloxacin and colistin proved nonsignificant. A significant DOT decrease was observed for aminoglycosides (P<0.001), cephalosporins (P<0.001), quinolones (P<0.001) and carbapenems (P<0.001).

CONCLUSIONS

No significant association was observed between consumption of each antipseudomonal antibiotic family and the respective resistance rates for P. aeruginosa strains identified in IDRI.

Molecular epidemiology, antimicrobial susceptibility, and characterization of fluoroquinolone non-susceptible Streptococcus pyogenes in Japan

Streptococcus pyogenes (Group A streptococci: GAS) are known to cause a wide variety of human illnesses, some of which can be life-threatening. Usually, penicillin is the first-choice agent for the treatment of GAS infections. For patients with penicillin or beta-lactam antibiotics allergies, macrolide drugs are recommended as an alternative therapy. However, an increased prevalence of macrolide-resistant GAS (MRGAS) has been reported in many countries. Furthermore, fluoroquinolone non-susceptible GAS has been reported. The present study was focused on determining the features of fluoroquinolone non-susceptible strains collected from children with pharyngotonsillitis in the southwestern areas of Japan. To reveal the characteristics of fluoroquinolone non-susceptible GAS, we investigated the MIC, T-serotype, emm typing, and PFGE of 298 GAS strains isolated in the Fukuoka southwest area of Japan between 2011 and 2013. We determined that fluoroquinolone non-susceptibility shows a MIC to tosufloxacin of ≧1 μg/ml. We identified 33 (11.1%) fluoroquinolone non-susceptible GAS strains. In these strains, 6 T-serotypes and 9 emm/MLST patterns were detected. The predominant combinations were emm6/ST382 (14 strains, 42.4%) and emm89/ST101 (5 strains, 15.2%). PFGE classified 10 pulsotypes, and each was quite different. These results showed that fluoroquinolone non-susceptible GAS strains have a variety of origins. The usage of fluoroquinolone drugs could have a negative effect on the antimicrobial drug sensitivity of GAS in Japan. Considering such a situation, continuous monitoring of quinolone non-susceptible GAS is necessary.

Carbapenem-resistant Pseudomonas aeruginosa and carbapenem use in Japan: an ecological study

Objective

This study focused on carbapenem resistance in Pseudomonas aeruginosa and examined potential ecological correlations with carbapenem use in Japan.

Methods

The proportion of carbapenem-resistant P. aeruginosa isolates from 2015 and 2016 by prefecture was obtained from the Japan Nosocomial Infections Surveillance system. Data on carbapenem use was obtained from the National Database of Health Insurance Claims. The correlation between the proportion of carbapenem-resistant isolates and carbapenem consumption was assessed in a cross-sectional manner. The study also collected information on other variables including the numbers of physicians, nurses and medical facilities per 100 000 individuals by prefecture.

Results

Both the proportion of carbapenem-resistant P. aeruginosa isolates and levels of carbapenem use were higher in western Japan. Using a multivariate model, only carbapenem use remained significantly associated with the proportion of carbapenem-resistant isolates.

Conclusions

Carbapenem use and the proportion of carbapenem-resistant P. aeruginosa isolates were positively correlated. By longitudinal data collection, this approach offers an avenue to establish causal links as the frequency of carbapenem-resistant P. aeruginosa isolates starts to change in the future.

The impact analysis of a multiplex PCR respiratory panel for hospitalized pediatric respiratory infections in Japan

Background

Rapid molecular diagnosis of infections has contributed to timely treatments and antimicrobial stewardship. However, the benefit and cost-effectiveness vary in each country or community because they have different standard practices and health care systems. In Japan, rapid antigen tests (RATs) have been frequently used for pediatric respiratory infections. We investigated the impact and cost-effectiveness of a multiplex PCR (mPCR) respiratory panel for pediatric respiratory infections in a Japanese community hospital.

Methods

We replaced RATs with an mPCR respiratory panel (FilmArray®) for admitted pediatric respiratory infections on March 26, 2018. We compared the days of antimicrobial therapy (DOT) and length of stay (LOS) during the mPCR period (March 2018 to April 2019) with those of the RAT period (March 2012 to March 2018).

Results

During the RAT and mPCR periods, 1132 and 149 patients were analyzed. The DOT/case was 12.82 vs 8.56 (p < 0.001), and the LOS was 8.18 vs 6.83 days (p = 0.032) in the RAT and mPCR groups, respectively. The total costs during admissions were ∖258,824 ($2331.7) and ∖243,841 ($2196.8)/case, respectively. Pathogen detection rates were 30.2% vs 87.2% (p < 0.001).

Conclusion

Compared to conventional RATs, the mPCR test contributed to a reduction in the DOT and LOS in a Japanese community hospital for admission-requiring pediatric respiratory infections. However, a proper stewardship program is essential to further reduce the unnecessary usage of antimicrobials.

The intervention by an antimicrobial stewardship team can improve clinical and microbiological outcomes of resistant gram-negative bacteria

Antibiotic stewardship (AS) improves patient outcomes and rates of antibiotic susceptibilities. However, the long-term effect of AS programs (ASPs) on mortality is unclear. This study aimed to assess the impact of bedside interventions by an AS team (AST) on clinical and microbiological outcomes. This retrospective study enrolled patients with bloodstream infections (BSI) and long-term use of broad-spectrum antibiotics (more than 7 days). The main outcomes were 30-day and in-hospital mortality of patients with BSI. The secondary outcomes were the day of therapy (DOT) and susceptibility of antipseudomonal agents. Cases were classified into two groups: the pre-ASP group comprised cases between 2011 and 2013 and the post-ASP group, between 2014 and 2016. The outcomes were then compared between the two groups. Among the patients with all BSI (n = 1187), no significant differences in 30-day mortality were observed between those in the pre-ASP and post-ASP groups. However, in-hospital mortality was significantly lower in the post-ASP group than that in the pre-ASP group (24.8% vs. 18.0%; P = 0.004). Furthermore, the 30-day and in-hospital mortality of resistant gram-negative bacteraemia was significantly lower (20.4% vs.10.5%; P = 0.04 and 28.0% vs.16.1%; P = 0.03). The DOT of broad-spectrum antibiotics decreased except that of tazobactam/piperacillin. The susceptibilities of tazobactam/piperacillin, ceftazidime, cefepime, sulbactam/cefoperazone, gentamicin, ciprofloxacin levofloxacin, imipenem and meropenem were significantly better. Interventions by the AST can improve the clinical and microbiological outcomes, especially resistant gram-negative bacteria. Furthermore, this effect of our ASP can continue for a long term.

[The Role of Pharmacists in Antimicrobial Stewardship]

Antimicrobial resistance (AMR) has been declared a global public health emergency, necessitating the involvement of the whole of society to address this increasingly serious threat. AMR causes prolonged illness, greater risk of infection spread, increased morbidity, and higher mortality rates, which result in increased expenses to the government, healthcare services, and individuals. Inappropriate use of antimicrobials has been indicated as the primary cause for the global expansion of AMR. Under these circumstances, various countries have formulated suitable national action plans to curb AMR. In Japan, the national action plan on AMR was announced in April 2016. Our previous study clarified that orally administered antimicrobials accounted for approximately 90% of total consumption: oral third-generation cephalosporins, macrolides, and fluoroquinolones accounted for approximately 77% of oral consumption. Therefore pharmacists must extend their support for the appropriate use of antimicrobials prescribed by attending physicians to not only hospitalized patients but also outpatients. "Choosing wisely," a US-based health education campaign, warns against unnecessary use of antimicrobials. Pharmacists should strive to disseminate the concept of "choosing wisely" in relation to other medicines, implement further interventions, and evaluate them. In this article, we present data on use of antimicrobials in Japan, and mention how pharmacists should be involved in enabling physicians choose antimicrobials wisely.

Multiclonal Expansion and High Prevalence of β-Lactamase-Negative Haemophilus influenzae with High-Level Ampicillin Resistance in Japan and Susceptibility to Quinolones

β-Lactam-resistant Haemophilus influenzae is a clinical concern. A high prevalence (>40%) of β-lactamase-negative high-level ampicillin-resistant H. influenzae (high-BLNAR) isolates in Japan has been reported. However, the reasons for the expansion are unknown. High-BLNAR strains possess an amino acid substitution, either Asn526Lys (group III) or Arg517His (group III-like) in addition to Ser385Thr, in penicillin-binding protein 3 (PBP3). To determine the current prevalence of high-BLNAR strains and the mechanisms behind their expansion in Japan, their prevalence, PBP3 types, multilocus sequence types, and susceptibilities to quinolones approved in Japan as alternatives were determined. Sixty percent of H. influenzae clinical isolates (62/104 isolates) were β-lactamase-negative ampicillin-resistant H. influenzae (BLNAR) strains. Among BLNAR isolates, 92% (57/62 isolates) were high-BLNAR strains. Most isolates were classified as belonging to group III, which contained many genotypes (11 PBP3 types and 25 sequence types). These results indicated that the expansion of high-BLNAR isolates was multiclonal and such strains are still predominant in Japanese clinical settings. One high-BLNAR isolate harbored the novel amino acid substitution Asn526Met in addition to Ser385Thr in PBP3, suggesting a new group (group IV). No quinolone-resistant H. influenzae isolates were identified. The MICs for the quinolones (moxifloxacin, garenoxacin, and tosufloxacin) were similar to that for levofloxacin, whereas sitafloxacin exhibited a lower MIC. However, we obtained 4 H. influenzae isolates with decreased quinolone susceptibility with the amino acid substitution Ser84Leu in GyrA, and 3 of those isolates were high-BLNAR isolates. In summary, this study shows that multiclonal high-BLNAR strains predominate in a Japanese university hospital. Isolates remain sensitive to quinolones, but vigilance is required to prevent the development of fluoroquinolone resistance in high-BLNAR strains.

Introducing an antibiotic stewardship program in a pediatric center in China

BACKGROUND

This study aimed to investigate the effect of antibiotic stewardship programs (ASP) on reducing antimicrobial resistance rate, antibiotics consumption and multi-drug resistance bacterial infections in the pediatric patients.

METHODS

This study was carried out in the Pediatric Center of a tertiary hospital of Shandong Province, China. The study duration was separated into two periods according to introduction of ASP (began from April 2011). Before intervention: from April 2009 to March 2011; after intervention: from April 2012 to March 2014. The consumption of antibiotics, defined daily dose (DDD), isolation of multidrug-resistant organisms (MDRO) and resistance rate of antibiotics were analyzed and compared between the two study periods.

RESULTS

Total antibiotics consumption (DDDs) reduced from 56,725 in 2011 to 31,380 in 2014; antibiotic use density (AUD) reduced from 93.8 to 43.5; mean (± SD) antibiotic costs per patient (per quarter) decreased from 637 (± 29) RMB to 462 (± 49) RMB; and the mean total drug consumption (g)/DDD (DDDs) for inpatients decreased from 90.4 (± 3.3) to 56.4 (± 9.5). Multidrug-resistant microorganisms isolation reduced significantly from 463 (20.0) to 216 (6.9%). Resistance rate of general spectrum antibiotics reduced remarkably after intervention. The proportion of patients colonized or infected with Carbapenems-resistant Acinetobacter baumannii was correlated with DDDs of carbapenem.

CONCLUSIONS

Implementation of ASP leads to reduced medical expense, decrease of improper and abuse of antibiotics, and reduced antibiotics resistance rate and MDRO isolation. Continuous efforts to improve antibiotic use are required.

Long-term efficacy of comprehensive multidisciplinary antibiotic stewardship programs centered on weekly prospective audit and feedback

OBJECTIVE

To evaluate the long-term effects of comprehensive antibiotic stewardship programs (ASPs) on antibiotic use, antimicrobial-resistant bacteria, and clinical outcomes.

DESIGN

Before-after study.

SETTING

National university hospital with 934 beds.

INTERVENTION

Implementation in March 2010 of a comprehensive ASPs including, among other strategies, weekly prospective audit and feedback with multidisciplinary collaboration.

METHODS

The primary outcome was the use of antipseudomonal antibiotics as measured by the monthly mean days of therapy per 1000 patient days each year. Secondary outcomes included overall antibiotic use and that of each antibiotic class, susceptibility of Pseudomonas aeruginosa, the proportion of patients isolated methicillin-resistant Staphylococcus aureus (MRSA) among all patients isolated S. aureus, the incidence of MRSA, and the 30-day mortality attributable to bacteremia.

RESULTS

The mean monthly use of antipseudomonal antibiotics significantly decreased in 2011 and after as compared with 2009. Susceptibility to levofloxacin was significantly increased from 2009 to 2016 (P = 0.01 for trend). Its susceptibility to other antibiotics remained over 84% and did not change significantly during the study period. The proportion of patients isolated MRSA and the incidence of MRSA decreased significantly from 2009 to 2016 (P < 0.001 and = 0.02 for trend, respectively). There were no significant changes in the 30-day mortality attributable to bacteremia during the study period (P = 0.57 for trend).

CONCLUSION

The comprehensive ASPs had long-term efficacy for reducing the use of the targeted broad-spectrum antibiotics, maintaining the antibiotic susceptibility of P. aeruginosa, and decreasing the prevalence of MRSA, without adversely affecting clinical outcome.

Antimicrobial stewardship of Chinese ministry of health reduces multidrug-resistant organism isolates in critically ill patients: a pre-post study from a single center

Background

China’s Ministry of Health (MOH) has established a policy about the antimicrobial stewardship. To date, the effects of this policy on multidrug-resistant organism (MDRO) in critically ill patients are unknown.

Methods

A pre-post study was conducted on intensive care unit (ICU) patients from June 2010 to May 2011 and from June 2012 to May 2013. Bacterial cultures were conducted at ICU admission and discharge. In June 2011, our hospital started to administer the antimicrobial stewardship program of Chinese MOH. We collected the data on antimicrobial consumption during the 3-year period in all hospital and individual department every month, and analyzed the correlation between the proportion of critically patients colonized or infected with MDRO and antimicrobial consumption.

Results

A total of 978 patients were involved in the present study. With the intervention, the monthly mean Defined Daily Dose (DDD) per 100 occupied bed-days throughout the hospital decreased from 96 ± 7 to 65 ± 6 (p < 0.001), and the proportion of patients colonized or infected with MDRO decreased from 36 to 13% at the time of ICU admission and declined from 48 to 29% at the time of ICU discharge (both p < 0.001). There was a significant positive relationship between the proportion of all critically ill patients colonized or infected with MDRO at ICU admission and the DDD of the entire hospital (R² = 0.7858, p < 0.001).

Conclusion

The antimicrobial stewardship program of Chinese MOH reduced the consumption of antibiotics. Moreover, the proportion of patients colonized or infected with MDRO decreased along with reduced consumption of antibiotics.

Trial registration

Retrospectively registered: NCT02128399; Date of registration: 22 APR 2014; Detail information web link: https://clinicaltrials.gov/ct2/show/NCT02128399?term=NCT02128399&rank=1

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-2051-8) contains supplementary material, which is available to authorized users.

Japanese antimicrobial consumption surveillance: First report on oral and parenteral antimicrobial consumption in Japan (2009-2013)

No reliable national antimicrobial consumption data have been available in Japan. The Japanese antimicrobial consumption surveillance (JACS) project started to collect data nationwide on antimicrobial consumption. This paper provides the first sales data from the JACS project on oral and parenteral antimicrobial consumption in Japan as well as the trends for the years from 2009 to 2013. The population-weighted total consumption was expressed as defined daily doses (DDDs) per 1000 inhabitants per day (DID). The value of DID increased from 14.7 in 2009 to 15.8 in 2013. Notably, oral antimicrobials accounted for 92.6% (mean of 2009, 2011 and 2013) of total consumption. Oral third-generation cephalosporins, macrolides and fluoroquinolones accounted for 77.1% (mean of 2009, 2011 and 2013) of oral consumption. Consumption of antimicrobials has increased during the years 2009 and 2013 regardless of the dosage form. This is the first report regarding the population-weighted consumption of oral and parenteral antimicrobials in Japan during the years 2009 and 2013. These results provide useful information for combating the menace of antimicrobial resistance in Japan.

Multidrug Resistance in Non-PCV13 Serotypes of Streptococcus pneumoniae in Northern Japan, 2014

Since the implementation of routine PCV13 immunization in Japan, nonvaccine serotypes (NVTs) have been increasing among clinical isolates of Streptococcus pneumoniae. In this study, susceptibility to 18 antibiotics was tested for all the 231 isolates with NVTs, which were collected from children <16 years of age in northern Japan in 2014 (July-November). High resistance rates were observed for macrolides (>90.9%), tetracycline (91.3%), and clindamycin (75.3%), while penicillin (PEN) nonsusceptibility (PNSP; MIC ≥0.12 μg/ml) was detected in 42.9% of the pneumococci [39.4%; PEN-intermediate S. pneumoniae (PISP), 3.5%; PEN-resistant S. pneumoniae (PRSP)]. All serotype 15A isolates were PRSP (MIC, ≥2 μg/ml) or PISP, and PNSP was prevalent in also serotypes 23A (96.9%), 6C (41%), and 35B (33.3%). Overall, 42.0% of the isolates showed multidrug resistance (MDR). Sequence types (STs) determined for 20 PNSP isolates with NVTs were ST63 (15A), STs 242 or 5832 (6C), STs 338 or 5242 (23A), and ST558 (35B). All the PNSP isolates possessed tet(M), and erm(B) or mefA(A/E), and 70% of them were gPRSP having three altered genes pbp1a, pbp2x, and pbp2b. Among alterations in transpeptidase-coding region of penicillin-binding proteins (PBPs), two substitutions of T₃₇₁S in the STMK motif and TSQF_574-577NTGY in PBP1a were common to all PRSP isolates. The present study showed the spread of PNSP in NVTs 15A, 23A, 6C, and 35B, and the emergence of the MDR international clone Sweden^15A-ST63 in northern Japan.

Identification of Enterococcus faecium and Enterococcus faecalis as vanC-type Vancomycin-Resistant Enterococci (VRE) from sewage and river water in the provincial city of Miyazaki, Japan

As a first step for assessing the risk to human health posed by vancomycin-resistant enterococci (VRE) in the aquatic environment, we screened sewage and urban river water samples from Miyazaki, Japan for VRE. Because vancomycin-resistant organisms are not as prevalent in sewage and river water as vancomycin-susceptible organisms, the samples were screened by minimum inhibitory concentration test using the vancomycin-supplemented membrane-Enterococcus indoxyl-β-d-glucoside (mEI) agar. The isolates, presumed to be enterococci, were identified using 16S rRNA sequencing analysis. The percentages of VRE isolates screened using 4 μg mL(-1) vancomycin-supplemented mEI agar from sewage and urban river water samples were 12% and 24%, respectively. The vancomycin-resistant genes vanC1 and vanC2/3 were detected in the isolates from both samples by PCR analysis. All enterococci isolates containing vanC1, which is a specific gene for vanC-type of VRE, were identified as Enterococcus casseliflavus/gallinarum. Further, 92% enterococci isolates containing vanC2/3 were identified as E. casseliflavus/gallinarum, the remaining isolates containing vanC2/3 were E. faecium (4%) and E. faecalis (4%). Thereafter, the distribution of E. faecium and E. faecalis, which are the major types of enterococci in humans containing vanC2/3, was observed in the water samples collected.

Virulence attributes in Brazilian clinical isolates of Pseudomonas aeruginosa

Pseudomonas aeruginosa is an opportunistic human pathogen responsible for causing a huge variety of acute and chronic infections with significant levels of morbidity and mortality. Its success as a pathogen comes from its genetic/metabolic plasticity, intrinsic/acquired antimicrobial resistance, capacity to form biofilm and expression of numerous virulence factors. Herein, we have analyzed the genetic variability, antimicrobial susceptibility as well as the production of metallo-β-lactamases (MBLs) and virulence attributes (elastase, pyocyanin and biofilm) in 96 strains of P. aeruginosa isolated from different anatomical sites of patients attended at Brazilian hospitals. Our results revealed a great genetic variability, in which 86 distinct RAPD types (89.6% of polymorphisms) were detected. Regarding the susceptibility profile, 48 strains (50%) were resistant to the antimicrobials, as follows: 22.92% to the three tested antibiotics, 12.5% to both imipenem and meropenem, 11.46% to ceftazidime only, 2.08% to imipenem only and 1.04% to both ceftazidime and meropenem. Out of the 34 clinical strains of P. aeruginosa resistant to both imipenem and meropenem, 25 (73.53%) were MBL producers by phenotypic method while 12 (35.29%) were PCR positive for the MBL gene SPM-1. All P. aeruginosa strains produced pyocyanin, elastase and biofilm, although in different levels. Some associations were demonstrated among the susceptibility and/or production of these virulence traits with the anatomical site of strain isolation. For instance, almost all strains isolated from urine (85.71%) were resistant to the three antibiotics, while the vast majority of strains isolated from rectum (95%) and mouth (66.67%) were susceptible to all tested antibiotics. Urine isolates produced the highest pyocyanin concentration (20.15±5.65 μg/ml), while strains isolated from pleural secretion and mouth produced elevated elastase activity (1441.43±303.08 FAU) and biofilm formation (OD590 0.676±0.32), respectively. Also, MBL-positive strains produced robust biofilm compared to MBL-negative strains. Collectively, the production of site-dependent virulence factors can be highlighted as potential therapeutic targets for the treatment of infections caused by heterogeneous and resistant strains of P. aeruginosa.