Evaluation of regional antibiograms to monitor antimicrobial resistance in Hampton Roads, Virginia

A Situation Analysis of the Capacity of Laboratories in Faith-Based Hospitals in Zambia to Conduct Surveillance of Antimicrobial Resistance: Opportunities to Improve Diagnostic Stewardship

Antimicrobial resistance (AMR) is a public health problem exacerbated by the overuse and misuse of antibiotics and the inadequate capacity of laboratories to conduct AMR surveillance. This study assessed the capacity of laboratories in seven faith-based hospitals to conduct AMR testing and surveillance in Zambia. This multi-facility, cross-sectional exploratory study was conducted from February 2024 to April 2024. We collected and analysed data using the self-scoring Laboratory Assessment of Antibiotic Resistance Testing Capacity (LAARC) tool. This study found an average score of 39%, indicating a low capacity of laboratories to conduct AMR surveillance. The highest capacity score was 47%, while the lowest was 25%. Only one hospital had a full capacity (100%) to utilise a laboratory information system (LIS). Three hospitals had a satisfactory capacity to perform data management with scores of 83%, 85%, and 95%. Only one hospital had a full capacity (100%) to process specimens, and only one hospital had good safety requirements for a microbiology laboratory, with a score of 89%. This study demonstrates that all the assessed hospitals had a low capacity to conduct AMR surveillance, which could affect diagnostic stewardship. Therefore, there is an urgent need to strengthen the microbiology capacity of laboratories to enhance AMR surveillance in Zambia.

AntibiogramDSM: a combined local antibiogram and educational intervention

Objective

To describe the development of a combined local antibiogram and assess its utility in an educational intervention.

Design

Retrospective analysis of a combined, multi-healthcare system antibiogram with an educational intervention and pre-post analysis.

Setting

Creation of the combined antibiogram included all health systems in Des Moines, Iowa. The educational intervention was delivered live via webinar and remained available on demand for one year.

Participants

The combined antibiogram participants included four health systems representing eight hospitals. The educational intervention included 45 healthcare providers (15 live, 30 on demand) who elected to participate.

Methods

Yearly antibiograms were collected from four health systems for 2017 and 2018 and from three health systems for 2019 and 2020. Each was aggregated into a single antibiogram, posted online, and analyzed retrospectively. In 2021, an educational intervention took place, which included pre-educational assessments, a one-hour presentation on local resistance rates and impact on common infections, and post-education assessments. The educational session was available online for one year. Correct responses before and after education were compared using NcNemar's test.

Results

Over 4 yr, 123,168 isolates were included in the antibiogram, representing 57 species and 46 tested antibiotics. Before education, prediction of local resistance rates for E. coli and S. pneumoniae was poor. After the education session, there was improvement in the proportion of correct responses to case-based questions: pneumonia (31.8% vs 58.8%, P = 0.022), UTI (47.7% vs 85.3%, P < 0.001), sinusitis (75% vs 91.2%, P = 0.109), and diverticulitis (43.2% vs 88.2%, P = 0.002).

Conclusions

A combined local antibiogram was useful in supporting an outpatient education program.

Providing value to patients and providers via a pediatric statewide antibiogram in South Carolina

Objective

Antimicrobial stewardship has special challenges in particular populations and facilities, including pediatrics. We sought to augment the information available to antimicrobial stewardship programs (ASPs) by created a cumulative statewide antibiogram for neonatal and pediatric populations.

Methods

In the Antimicrobial Stewardship Collaborative of South Carolina (ASC-SC), we created statewide antibiograms, including a separate antibiogram accounting for the pediatric and neonatal intensive care unit (NICU) populations. We collated data from the 4 pediatric and 3 NICU facilities in the state to provide a cumulative statewide antibiogram.

Results

Methicillin-susceptible Staphylococcus aureus was more prevalent than methicillin-resistant Staphylococcus aureus. Pseudomonas aeruginosa, Citrobacter koserii, and Acinetobacter baumannii were isolated in only 1 NICU.

Conclusions

These antibiograms should improve empiric prescribing in both the inpatient and outpatient setting, providing data in some areas that historically do not have pediatric antibiogram to inform prescribing. The antibiogram alone is not sufficient independently to improve prescribing but is one important aspect of stewardship in the pediatric population of South Carolina.

Development of a 51-hospital Chicagoland regional antibiogram and comparison to local hospital and national surveillance data

OBJECTIVE

To develop a regional antibiogram within the Chicagoland metropolitan area and to compare regional susceptibilities against individual hospitals within the area and national surveillance data.

DESIGN

Multicenter retrospective analysis of antimicrobial susceptibility data from 2017 and comparison to local institutions and national surveillance data.

SETTING AND PARTICIPANTS

The analysis included 51 hospitals from the Chicago-Naperville-Elgin Metropolitan Statistical Area within the state of Illinois. Overall, 18 individual collaborator hospitals provided antibiograms for analysis, and data from 33 hospitals were provided in aggregate by the Becton Dickinson Insights Research Database.

METHODS

All available antibiogram data from calendar year 2017 were combined to generate the regional antibiogram. The final Chicagoland antibiogram was then compared internally to collaborators and externally to national surveillance data to assess its applicability and utility.

RESULTS

In total, 167,394 gram-positive, gram-negative, fungal, and mycobacterial isolates were collated to create a composite regional antibiogram. The regional data represented the local institutions well, with 96% of the collaborating institutions falling within ±2 standard deviations of the regional mean. The regional antibiogram was able to include 4-5-fold more gram-positive and -negative species with ≥30 isolates than the median reported by local institutions. Against national surveillance data, 18.6% of assessed pathogen-antibiotic combinations crossed prespecified clinical thresholds for disparity in susceptibility rates, with notable trends for resistant gram-positive and gram-negative bacteria.

CONCLUSIONS

Developing an accurate, reliable regional antibiogram is feasible, even in one of the largest metropolitan areas in the United States. The biogram is useful in assessing susceptibilities to less commonly encountered organisms and providing clinicians a more accurate representation of local antimicrobial resistance rates compared to national surveillance databases.

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.

Diagnostic Microbiology from the Beginning to the Future: Regional Antibiograms as Public Health Tools to Slow Down Antibiotic Resistance

Infectious diseases is the only area of medicine where we can isolate the cause and study it in the laboratory under conditions similar to human body. Once isolated, we are able to determine the most optimal drug to treat it. Unfortunately, it is also the only specialty where after making truly wondrous strides we find ourselves at the crossroads of a public health crisis in the form of ongoing antibiotic resistance. Among the factors responsible for the current status, is the suboptimal utilization of the diagnostic microbiology laboratory. In this review authors provide a short historical perspective of diagnostic microbiology. The focus of discussion is the generation and utilization of cumulative antibiograms at the institutional and regional levels and discuss the pitfalls in large national databases with respect to the day-to-day patient care. This public health tool to slow down antibiotic resistance happens to be low-tech and inexpensive.

Antibiograms Cannot Be Used Interchangeably Between Acute Care Medical Centers and Affiliated Nursing Homes

OBJECTIVE

To determine whether antibiograms for Veterans Affairs (VA) nursing homes (NHs), termed Community Living Centers, are similar to those from their affiliated acute care medical centers.

DESIGN

Descriptive study.

SETTING AND PARTICIPANTS

We compared the 2017 antibiograms for VA NHs to their affiliated VA medical centers (VAMCs). Antibiograms included antibiotic susceptibility rates for commonly observed bacteria in this setting (Staphylococcus aureus, Enterococcus spp, Escherichia coli, Klebsiella spp, Proteus mirabilis, and Pseudomonas aeruginosa).

METHODS

Antibiograms were considered to be in complete agreement when the overall susceptibility rate between the NH and affiliated VAMC was either at or above 80% or below 80% across all bacteria and antibiotics. Average percentage of bacteria-antibiotic comparisons in disagreement per facility pair, and number of facilities with agreement for specific bacteria-antibiotic comparisons were also assessed. The chi-square test was used to compare disagreement between NH-VAMC facilities based on geographic proximity of the NH to the VAMC, culture source, and bed size.

RESULTS

A total of 119 NH-VAMC affiliate pairs were included in this analysis, with 71% (84/119) on the same campus and 29% (35/119) on geographically distinct campuses. None of the NH-VAMC pairs demonstrated complete agreement (all bacteria vs all antibiotics) between their antibiograms. On average, 20% of the bacteria-antibiotic comparisons from the antibiogram disagreed clinically per NH-VAMC pair, and almost twice as often the nursing home had lower susceptibility (higher resistance) than the acute care facility. Some bacteria-antibiotic comparisons agreed in all facilities (eg, E coli-imipenem; S aureus-linezolid; S aureus-vancomycin), while others showed greater disagreement (eg, Klebsiella spp-cefazolin; Klebsiella spp-ampicillin-sulbactam; P aeruginosa-ciprofloxacin). Rates of clinical disagreement were similar by geographic proximity of the NH to the VAMC, culture source, and bed size.

CONCLUSIONS AND IMPLICATIONS

Overall, this study showed a moderate lack of agreement between VA NH antibiograms and their affiliate VAMC antibiograms. Our data suggest that antibiograms of acute care facilities are often not accurate approximations of the nursing home resistance patterns and therefore should be used with caution (if at all) in guiding empiric antibiotic therapy.

Creating reasonable antibiograms for antibiotic stewardship programs in nursing homes: Analysis of 260 facilities in a large geographic region, 2016–2017

Objective:

To determine the best nursing home facility characteristics for aggregating antibiotic susceptibility testing results across nursing homes to produce a useful annual antibiogram that nursing homes can use in their antimicrobial stewardship programs.

Design:

Derivation cohort study.

Setting:

Center for Medicare and Medicaid Services (CMS) certified skilled nursing facilities in Georgia (N = 231).

Participants:

All residents of eligible facilities submitting urine culture specimens for microbiologic testing at a regional referral laboratory.

Methods:

Crude and adjusted metrics of antibiotic resistance prevalence (percent of isolates testing susceptible) for 5 bacterial species commonly recovered from urine specimens were calculated using mixed linear models to determine which facility characteristics were predictive of testing antibiotic susceptibility.

Results:

In a single year, most facilities had an insufficient number of isolates tested to create facility-specific antibiograms: 49% of facilities had sufficient Escherichia coli isolates tested, but only about 1 in 10 had sufficient isolates of Klebsiella pneumoniae, Proteus mirabilis, Enterococcus faecalis, or Pseudomonas aeruginosa. After accounting for antibiotic tested and age of the patient, facility characteristics predictive of susceptibility were: E. coli, region, year, average length of stay; K. pneumoniae, region, bed size; P. mirabilis, region; and for E. faecalis or P. aerginosa no facility parameter remained in the model.

Conclusions:

Nursing homes often have insufficient data to create facility-specific antibiograms; aggregating data across nursing homes in a region is a statistically sound approach to overcoming data shortages in nursing home stewardship programs.

Antimicrobial Stewardship in Long-Term Care Facilities: Approaches to Creating an Antibiogram when Few Bacterial Isolates Are Cultured Annually

Antibiograms are important clinical tools to report and track antibiotic susceptibility and help guide empiric antimicrobial therapy. Antibiograms support compliance with antimicrobial stewardship (AMS) requirements from the Centers for Medicare and Medicaid Services and are in line with recommendations from the Centers for Disease Control and Prevention Core Elements of AMS for nursing homes/long-term care facilities (LTCFs). Unlike most acute-care settings, LTCFs are challenged in creating antibiograms because of the low number of bacterial isolates collected annually. Determining the best methodology for creating clinically useful antibiograms for LTCFs needs to be explored. Possible approaches include (1) extending the isolate data beyond 1 year, (2) combining isolate data from the same geographic region, (3) using a nearby acute-care facility's antibiogram as a proxy, or (4) collapsing isolate data. This article discusses the benefits and limitations of each approach.

Feasibility and Value of Developing a Regional Antibiogram for Community Hospitals

OBJECTIVETo determine the feasibility and value of developing a regional antibiogram for community hospitals.DESIGNMulticenter retrospective analysis of antibiograms.SETTING AND PARTICIPANTSA total of 20 community hospitals in central and eastern North Carolina and south central Virginia participated in this study.METHODSWe combined antibiogram data from participating hospitals for 13 clinically relevant gram-negative pathogen-antibiotic combinations. From this combined antibiogram, we developed a regional antibiogram based on the mean susceptibilities of the combined data.RESULTSWe combined a total of 69,778 bacterial isolates across 13 clinically relevant gram-negative pathogen-antibiotic combinations (median for each combination, 1100; range, 174-27,428). Across all pathogen-antibiotic combinations, 69% of local susceptibility rates fell within 1 SD of the regional mean susceptibility rate, and 97% of local susceptibilities fell within 2 SD of the regional mean susceptibility rate. No individual hospital had >1 pathogen-antibiotic combination with a local susceptibility rate >2 SD of the regional mean susceptibility rate. All hospitals' local susceptibility rates were within 2 SD of the regional mean susceptibility rate for low-prevalence pathogens (<500 isolates cumulative for the region).CONCLUSIONSSmall community hospitals frequently cannot develop an accurate antibiogram due to a paucity of local data. A regional antibiogram is likely to provide clinically useful information to community hospitals for low-prevalence pathogens.Infect Control Hosp Epidemiol 2018;39:718-722.

The challenges of designing a benchmark strategy for bioinformatics pipelines in the identification of antimicrobial resistance determinants using next generation sequencing technologies

Next-Generation Sequencing (NGS) technologies are expected to play a crucial role in the surveillance of infectious diseases, with their unprecedented capabilities for the characterisation of genetic information underlying the virulence and antimicrobial resistance (AMR) properties of microorganisms.  In the implementation of any novel technology for regulatory purposes, important considerations such as harmonisation, validation and quality assurance need to be addressed.  NGS technologies pose unique challenges in these regards, in part due to their reliance on bioinformatics for the processing and proper interpretation of the data produced.  Well-designed benchmark resources are thus needed to evaluate, validate and ensure continued quality control over the bioinformatics component of the process.  This concept was explored as part of a workshop on "Next-generation sequencing technologies and antimicrobial resistance" held October 4-5 2017.   Challenges involved in the development of such a benchmark resource, with a specific focus on identifying the molecular determinants of AMR, were identified. For each of the challenges, sets of unsolved questions that will need to be tackled for them to be properly addressed were compiled. These take into consideration the requirement for monitoring of AMR bacteria in humans, animals, food and the environment, which is aligned with the principles of a “One Health” approach.

The challenges of designing a benchmark strategy for bioinformatics pipelines in the identification of antimicrobial resistance determinants using next generation sequencing technologies

Next-Generation Sequencing (NGS) technologies are expected to play a crucial role in the surveillance of infectious diseases, with their unprecedented capabilities for the characterisation of genetic information underlying the virulence and antimicrobial resistance (AMR) properties of microorganisms.  In the implementation of any novel technology for regulatory purposes, important considerations such as harmonisation, validation and quality assurance need to be addressed.  NGS technologies pose unique challenges in these regards, in part due to their reliance on bioinformatics for the processing and proper interpretation of the data produced.  Well-designed benchmark resources are thus needed to evaluate, validate and ensure continued quality control over the bioinformatics component of the process.  This concept was explored as part of a workshop on "Next-generation sequencing technologies and antimicrobial resistance" held October 4-5 2017.   Challenges involved in the development of such a benchmark resource, with a specific focus on identifying the molecular determinants of AMR, were identified. For each of the challenges, sets of unsolved questions that will need to be tackled for them to be properly addressed were compiled. These take into consideration the requirement for monitoring of AMR bacteria in humans, animals, food and the environment, which is aligned with the principles of a "One Health" approach.

Antimicrobial Stewardship: How the Microbiology Laboratory Can Right the Ship

Antimicrobial stewardship is a bundle of integrated interventions employed to optimize the use of antimicrobials in health care settings. While infectious-disease-trained physicians, with clinical pharmacists, are considered the main leaders of antimicrobial stewardship programs, clinical microbiologists can play a key role in these programs. This review is intended to provide a comprehensive discussion of the different components of antimicrobial stewardship in which microbiology laboratories and clinical microbiologists can make significant contributions, including cumulative antimicrobial susceptibility reports, enhanced culture and susceptibility reports, guidance in the preanalytic phase, rapid diagnostic test availability, provider education, and alert and surveillance systems. In reviewing this material, we emphasize how the rapid, and especially the recent, evolution of clinical microbiology has reinforced the importance of clinical microbiologists' collaboration with antimicrobial stewardship programs.

Synergism and the mechanism of action of the combination of α-mangostin isolated from Garcinia mangostana L. and oxacillin against an oxacillin-resistant Staphylococcus saprophyticus

Background

Globally, staphylococci have developed resistance to many antibiotics. New approaches to chemotherapy are needed and one such approach could be to use plant derived actives with conventional antibiotics in a synergestic way. The purpose of this study was to isolate α-mangostin from the mangosteen (Garcinia mangostana L.; GML) and investigate antibacterial activity and mechanisms of action when used singly and when combined with oxacillin against oxacillin-resistant Staphylococcus saprophyticus (ORSS) strains. The isolated α-mangostin was confirmed by HPLC chromatogram and NMR spectroscopy. The minimum inhibitory concentration (MIC), checkerboard and killing curve were determined. The modes of action of these compounds were also investigated by enzyme assay, transmission electron microscopy (TEM), confocal microscopic images, and cytoplasmic membrane (CM) permeabilization studies.

Results

The MICs of isolated α-mangostin and oxacillin against these strains were 8 and 128 μg/ml, respectively. Checkerboard assays showed the synergistic activity of isolated α-mangostin (2 μg/ml) plus oxacillin (16 μg/ml) at a fractional inhibitory concentration index (FICI) of 0.37. The kill curve assay confirmed that the viability of oxacillin-resistant Staphylococcus saprophyticus DMST 27055 (ORSS-27055) was dramatically reduced after exposure to isolated α-mangostin (2 μg/ml) plus oxacillin (16 μg/ml). Enzyme assays demonstrated that isolated α-mangostin had an inhibitory activity against β-lactamase in a dose-dependent manner. TEM results clearly showed that these ORSS-27055 cells treated with this combination caused peptidoglycan and cytoplasmic membrane damage, irregular cell shapes and average cell areas were significantly larger than the control. Clearly, confocal microscopic images confirmed that this combination caused considerable peptidoglycan damage and DNA leakage. In addition, the CM permeability of ORSS-27055 was also increased by this combination of actives.

Conclusions

These findings provide evidence that isolated α-mangostin alone has not only some activity but also shows the synergistic activity with oxacillin against ORSS-27055. The chromone and isoprenyl structures could play a significant role in its action. This synergistic activity may involve three mechanisms of action. Firstly, potential effects of cytoplasmic membrane disruption and increases permeability. Secondly, inhibit β-lactamase activity. Finally, also damage to the peptidoglycan structure. We proposes the potential to develop a novel adjunct phytopharmaceutical to oxacillin for the treatment of ORSS. Future studies require clinical trials to establish if the synergy reported can be translated to animals and humans.