Cumulative Antibiograms Research Articles

Resistance is reality: findings from the first Ukrainian cumulative antibiogram.

Antimicrobial resistance is a global health threat resulting in significant morbidity and mortality worldwide. Until recently, in Ukraine, cumulative antibiograms (CuAbgms) have never been available. To describe the first CuAbgm developed in Ukraine. We developed a CuAbgm for the Okhmatdyt National Specialized Children's Hospital using data from WHONET. Antimicrobial susceptibility testing was performed per EUCAST guidelines. The CuAbgm was developed using guidance from CLSI. For Escherichia coli, 66% and 69% of isolates were susceptible to ceftazidime and ceftriaxone, respectively, and 99% were susceptible to meropenem. For Klebsiella pneumoniae, 26% and 27% of isolates were susceptible to ceftazidime and ceftriaxone, respectively, and only 59% were susceptible to meropenem. Of the carbapenem-resistant K. pneumoniae isolates that underwent additional susceptibility testing, only 38% were susceptible to ceftazidime/avibactam. For Pseudomonas aeruginosa, only 53% were susceptible to meropenem. Of those that were resistant to meropenem and underwent additional susceptibility testing, only 12% were susceptible to ceftazidime/avibactam. Similarly, for Acinetobacter spp., only 37% of isolates were susceptible to meropenem. Susceptibility to ampicillin/sulbactam was also low at 45%. The oxacillin susceptibility rate for Staphylococcus aureus was 99%. In this first-ever CuAbgm developed in Ukraine, high levels of resistance were demonstrated among Gram-negative bacteria. CuAbgms should be prioritized in laboratories in Ukraine to guide empirical antimicrobial therapy, infection control and antimicrobial stewardship policies. This is of heightened relevance during wartime, when there is a need for healthcare systems to treat complex and infected penetrating and blast-related injuries.

Uptake of Revised CLSI Breakpoints and Potential Impact among Hospitals Reporting to The NHSN AR Option, 2022

Background: Antimicrobial susceptibility testing (AST) is critical for detecting antimicrobial resistance (AR) and guiding antimicrobial treatment. The Clinical and Laboratory Standards Institute (CLSI) regularly publishes and revises breakpoints to guide the interpretation of AST results. In 2010–2019, CLSI has lowered many breakpoints for Enterobacterales and Pseudomonas aeruginosa. Timely implementation of updated breakpoints can vary across hospital laboratories, leading to shifts in the interpretation of AST results. This issue is a potential threat to the estimation of national prevalence estimates for AR and limits the comparability of AR data across hospitals. Hospitals submit AST data with clinical laboratory interpretations to the AR Option of CDC’s National Healthcare Safety Network (NHSN). NHSN tracks whether a hospital adopted the revised CLSI breakpoints for six organism-antimicrobial combinations involving AR phenotypes commonly associated with healthcare associated infections through hospital self-reporting status into a structured survey — 2022 NHSN Annual Hospital Survey (Table). For this analysis, we describe the uptake of revised CLSI breakpoints and compare cumulative antibiograms among hospitals that used various breakpoints. Methods: We included hospitals that completed the 2022 NHSN annual survey and submitted data to the NHSN AR Option for at least 9 months in 2022 by November 1, 2023. The percentage of hospitals that implemented CLSI breakpoints, published during 2010–2019, were determined for combinations of antibiotic class, organism, and CLSI revision year (Table). We calculated percent resistance (%R) as the number of isolates meeting AR phenotype definitions divided by the total number of Isolates tested for the following phenotypes: carbapenem-resistant Enterobacterales (CRE) which included E. coli, Klebsiella, and Enterobacter species; extended-spectrum cephalosporin-resistant Enterobacterales (ESC); carbapenem-non-susceptible P. aeruginosa; fluoroquinolone-resistant P. aeruginosa; and fluoroquinolone-resistant Enterobacterales. Results: Among the 741 hospitals included, 75%–93% implemented any of the six revised CLSI breakpoints (Table). The %R was higher among isolates from hospitals that adopted revised breakpoints compared to those that did not (p < 0 .0001). The largest difference was observed for carbapenem-non-susceptible P. aeruginosa (14.91% vs 10.11%). Conclusions: The uptake of revised CLSI breakpoints varied across hospitals, organism-antimicrobial combinations, and CLSI versions. This analysis indicates that the prevalence of AR for corresponding phenotypes could be underestimated if data from hospitals using higher, outdated breakpoints are included. It is important for NHSN to continue tracking breakpoints used in individual hospitals and encourage hospitals to report complete data on the original AST results, such as MIC, to optimize the accuracy of national AR surveillance.

Antimicrobial susceptibility patterns of aerobic bacteria isolated from canine urinary samples in South East Queensland, 2013 to 2018.

Urinary tract infections are a common diagnosis in dogs presenting to veterinary practice. Veterinarians often treat suspected infections empirically, either in the absence of culture and susceptibility testing results or whilst waiting for them. This study aimed to identify the bacteria most frequently isolated from canine urinary samples and their antimicrobial susceptibility patterns in South East Queensland (SEQ) to help guide responsible empirical antimicrobial prescription by the veterinary community in this geographical location. Cumulative antibiograms were generated from the results of 1284 culture-positive urinary samples in SEQ, obtained from a commercial veterinary laboratory over a 5-year period. Escherichia coli was the most commonly isolated bacterial species (43%), followed by Staphylococcus spp. (23%), Proteus spp. (21%) and Enterococcus spp. (10%). Of the six most common isolates, 97% had susceptibility to at least one low-importance antimicrobial. Susceptibility to the low-importance and first-line antimicrobial recommendation, amoxicillin, was 81% for E. coli and 24% for Staphylococcus spp. Susceptibility of both E. coli and Staphylococcus spp. to medium-importance and commonly recommended empirical antimicrobials, trimethoprim sulphonamides and amoxicillin-clavulanic acid was ≥85% and >92% for high-importance antimicrobials enrofloxacin and ceftiofur. Of the E. coli and Staphylococcus spp. isolates, 8.8% and 4%, respectively, were considered multidrug resistant. There was no increase in resistance to antimicrobials detected over the study period. Susceptibilities suggest low- and medium-importance antimicrobials remain acceptable first-line empirical treatments. However, this should be continually assessed and updated using local surveillance data.

Antimicrobial susceptibility of Gram-Negative Infections in King Faisal Medical Complex at Taif, Saudi Arabia

Objectives: Describe susceptibility patterns to several antimicrobials in Gram-negative pathogens isolated from patients in King FaisalMedical Complex (KFMC) at Taif, Saudi Arabia over a 6-month period. Methods: The study included a cumulative antibiogram of Gram-negative bacteria (GNB). Interpretation of the antimicrobial susceptibilitytests was based on the Clinical and Laboratory Standards Institute (CLSI) guidelines and the Phoenix system. Results: Overall, 763 clinical infections by GNB isolates of the specimens collected during six months were culture-positive. Amongthe array of GNB, Escherichia coli numbered 290 (38.0%) was the most frequently identified, then Klebsiella pneumoniae 276 (36.2%),Pseudomonas aeruginosa 77 (10.1%), Acinetobacter baumannii 48 (6.3%), Proteus spp. 31 (4.1%), Citrobacter koseri 11 (1.4%), Serratiaspp. 8 (1.0 %), Enterobacter aerogenes 7 (0.9%), Klebsiella Oxytoca 4 (0.5%), Providencia rettgeri 3 (0.4 %), Klebsiella ozaenae 3 (0.4%),Morganella morganii 2 (0.3%), Stenotrophomonas maltophilia 2 (0.3 %), and Pseudomonas puda 1 (0.1%). Fifty-one isolates were resistantto all tested antibiotics, but 97 (12.7 %) were susceptible to all the tested antibiotics. The majority (87.3%) of isolates were resistant toone or more antimicrobials tested. In general, 83% of the bacterial species were MDR. The carbapenem sensitivity was 68.7% for allGNB isolates, 47.3% and 52.3% of K. pneumoniae, 20.8% and 25% of Acinetobacter, and 64.1% and 75.6% of P. aeruginosa to imipenemand meropenem, respectively. The carbapenem sensitivity for E. coli was extremely high showing 100% and 99.9% for imipenem andmeropenem, respectively. Antibiotic sensitivity of the most isolated GNB pathogens was highly variable showing that tigecycline is themost effective antibiotic with 82.4% sensitivity while was non-effective for Acinetobacter. The colistin sensitivity was 88.3% for E. coli,69.2% for P. aeruginosa, 45.5% for K. pneumoniae and less effective against A. baumannii. Conclusion: Antibiotic resistance among K. pneumoniae, A. baumannii and P. aeruginosa was high for many used antibiotics, thus continued surveillance is needed.

Non-fermenter Gram-negative bacilli at a tertiary hospital, South Africa.

Non-fermenting Gram-negative bacilli (NFGNB) are a significant cause of healthcare-associated infections and are often implicated in nosocomial outbreaks. Non- fermenting Gram-negative bacilli tend to have variable susceptibility patterns that make the choice of empiric therapy difficult and thus treatment must be based on in vitro susceptibility testing of each antimicrobial agent. To describe the epidemiology of the NFGNB isolated from adult patients at Chris Hani Baragwanath Hospital (CHBAH) and to assess their antimicrobial susceptibility patterns in order to guide empiric therapy and inform infection prevention and control practices. Organisms isolated from sterile sites of adult in-patients between 01 January 2016 to 31 December 2018 were retrospectively analysed. A total of 2005 NFGNB isolated. Blood cultures were the most common specimen type (91.4%). Acinetobacter species were the most commonly isolated organisms (65.1%), followed by Pseudomonas species (26.5%). The majority of NFGNB were isolated from patients in surgical wards (38.9%) followed by medical wards (35.2%). Most (60%) of the Acinetobacter species were extremely drug resistant. Pseudomonas species were more susceptible than the Acinetobacter species with an overall susceptibility rate of 86% for Pseudomonas species. The rates of antimicrobial resistance demonstrated among Acinetobacter and Pseudomonas species were high, which illustrates the threat of antimicrobial resistance also seen worldwide. An emergence of NFGNB with intrinsic multidrug resistance (Stenotrophomonas maltophilia and Burkholderia cepacia) was noted. We suggest empiric therapy with a carbapenem sparing regimen of piperacillin-tazobactam in combination with amikacin and that empiric therapy be reviewed annually when cumulative antibiograms are done. Understanding of the distribution and antimicrobial susceptibility patterns of NFGNB at CHBAH.

Cumulative antibiogram preparation among hospitals participating in the Japan Surveillance for Infection Prevention and Healthcare Epidemiology

BackgroundThe cumulative antibiogram is essential to guide empirical therapy for infectious diseases and monitor the trend of antimicrobial resistance. However, the status of antibiogram generation at medical institutions in Japan is uncertain. MethodsA web-based questionnaire survey was conducted in February 2023 on the status of antibiogram preparation among facilities participating in the Japan Surveillance for Infection Prevention and Healthcare Epidemiology (J-SIPHE), an infection control surveillance system in Japan. ResultsThe questionnaire collection rate was 19.6% (379/1931). Of all facilities, 47% (178/379) performed microbiological tests mainly in-house, while 53% (201/379) performed microbiological tests mainly outsourced. Of all facilities, 78% (296/379) prepared antibiograms. Of those without antibiograms, 33% (27/83) were considering the development in the future. Some facilities cited staff shortage as a barrier to preparing antibiograms. Of the 214 facilities with antibiograms that could use the J-SIPHE system to prepare antibiograms, 19% (41/214) were using the J-SIPHE system to prepare their antibiograms. ConclusionsOne-quarter of the facilities that responded to the survey had not prepared antibiograms. Technical support for surveillance and awareness activity for using cumulative antibiograms might promote antibiogram preparation in Japan, which may improve antimicrobial stewardship and antimicrobial resistance measures.

Analysis of Cumulative Antibiogram Reports in Search for Optimal Empirical Urinary Tract Infection Treatment at the Central Teaching Hospital of the Medical University of Lodz, Poland: Results of a 3-Year Surveillance.

Urinary tract infections are among the most common bacterial infections, accounting for about two-fifths of all healthcare-associated infections. Appropriate antimicrobial therapy is crucial, e.g., to avoid prolonged hospitalization and limit antimicrobial resistance spread. This study was performed to analyze the microbiological profiles of urinary tract infections in the Central Teaching Hospital in Lodz, Poland, and develop local empirical therapy guidelines. This study was a 3-year retrospective surveillance of the cumulative antibiograms from urine cultures. The procedures were based on the current EUCAST and CLSI guidelines. In 2020-2022, a total of 4656 urine cultures were performed, of which 1134 were positive. The most common bacterial isolates were Escherichia coli, followed by Klebsiella spp. and Enterococcus spp. High levels of susceptibility (>90%) have been observed for carbapenems, piperacillin/tazobactam, amikacin, and nitrofurantoin. Development of the appropriate empirical antimicrobial is a challenging task with persistently high levels of resistance to commonly used antimicrobials. Eventually, we separated the uncomplicated and complicated urinary tract infections in local guidelines and recommended nitrofurantoin and amikacin, respectively, in empiric therapy. The clinicians should make a decision based on the presented symptoms and then-with the urine culture result-correct or continue the therapy.

Approaches Used to Construct Antibiograms for Dogs in a Veterinary Teaching Hospital in the United States.

Non-judicious antimicrobial use (AMU) is a major driver of antimicrobial resistance (AMR). In human hospitals, cumulative antibiograms are often used by clinicians to evaluate local susceptibility rates and to select the most appropriate empiric therapy with the aim of minimizing inappropriate AMU. However, the use of cumulative antibiograms to guide empiric antimicrobial therapy in veterinary hospitals in the United States is limited, and there are no specific guidelines or standardized methods available for the construction of antibiograms in veterinary clinical settings. The objective of this methods article is to describe the approaches that were used to construct antibiograms from clinical samples collected from dogs seen at a veterinary teaching hospital. Laboratory data for 563 dogs for the period from 1 January 2015 to 31 December 2015 was utilized. We used the Clinical and Laboratory Standards Institute (CLSI) guidelines for use in the construction of the antibiograms in human healthcare settings as the basis for the veterinary antibiograms. One general antibiogram and antibiograms stratified by hospital section, the anatomic region of sample collection/by sample type, were created and the challenges encountered in preparing these antibiograms were highlighted. The approaches described could be useful in guiding veterinary antibiogram development for empiric therapy.

Analysis of cumulative antibiogram reports in intensive care units at an Egyptian University Hospital

BackgroundInstitutions must have access to antibiograms to monitor changes in antimicrobial resistance and direct empirical antibiotic therapy. The first facility-specific cumulative antibiogram was launched in the ICU in 2019. Consequently, many antibiogram-operation-related actions have been adopted in the institution based on reported data. This study aimed to analyze the cumulative antibiogram reports for multiple intensive care units (ICUs) for 2020, and compare the antimicrobial susceptibility testing (AST) patterns between the 2019 and 2020 years in an academic medical center. MethodsThis cross-sectional study was performed of routine bacterial culture and AST data extracted from a laboratory information system in a 2252-bed capacity hospital. Only the first diagnostic isolate of a given species per patient per year was included in the study. Interpretation and reporting were done in accordance with the applicable Clinical and Laboratory Standards Institute and European Committee on Antimicrobial Susceptibility Testing guidelines. ResultsOf the 46,791 clinical isolates, the Gram-negative bacilli isolation rate witnessed a significant increase: 35,670 isolates in 2020 versus. 33,652 isolates in 2019. Klebsiella pneumoniae showed a statistically significant increase, mainly in pediatric, emergency, and cardiothoracic ICUs (p < 0.001). Neonatal and pediatric ICUs showed statistically significant increases in Pseudomonas aeruginosa and Proteus mirabilis isolates (p < 0.001). A statistically significant decrease was noted in the prevalence of Acinetobacter, Escherichia coli, Burkholderia cepacia, and Enterobacter cloacae. The sensitivities of K. pneumoniae and E. coli to imipenem and tigecycline significantly improved (p < 0.001). The sensitivity to colistin was significantly decreased (p < 0.001). The sensitivity of P. aeruginosa isolates to colistin and carbapenems was improved (p < 0.001). We reported a statistically significant decrease in all Gram-positive cocci (11,121 in 2020 versus. 11,528 in 2019). Staphylococcus aureus showed a statistically significant increase (p < 0.001), particularly in the medical ICU. ConclusionThe high susceptibility rates of Enterobacteriaceae toward colistin and tigecycline, should be cautiously considered in empiric therapy while looking for alternatives. The majority of isolates of Gram-positive cocci were coagulase negative staphylococci (CONS), we still need to confirm whether they are true pathogens or commensals before considering anti-staphylococcal agents in the empirical therapy. We underscored some corrective actions that might have improved the susceptibility rates, such as antibiotic cycling

Using an Antibiogram Profile to Improve Infection Control and Rational Antimicrobial Therapy in an Urban Hospital in The Gambia, Strategies and Lessons for Low- and Middle-Income Countries.

Antimicrobial resistance is a global health threat and efforts to mitigate it is warranted, thus the need for local antibiograms to improve stewardship. This study highlights the process that was used to develop an antibiogram to monitor resistance at a secondary-level health facility to aid empirical clinical decision making in a sub-Saharan African county. This retrospective cross-sectional descriptive study used 3 years of cumulative data from January 2016 to December 2018. Phenotypic data was manually imputed into WHONET and the cumulative antibiogram constructed using standardized methodologies according to CLSI M39-A4 guidelines. Pathogens were identified by standard manual microbiological methods and antimicrobial susceptibility testing was performed using Kirby-Bauer disc diffusion method according to CLSI M100 guidelines. A total of 14,776 non-duplicate samples were processed of which 1163 (7.9%) were positive for clinically significant pathogens. Among the 1163 pathogens, E. coli (n = 315) S. aureus (n = 232), and K. pneumoniae (n = 96) were the leading cause of disease. Overall, the susceptibility for E. coli and K. pneumoniae from all samples were: trimethoprim-sulfamethoxazole (17% and 28%), tetracycline (26% and 33%), gentamicin (72% and 46%), chloramphenicol (76 and 60%), and ciprofloxacin (69% and 59%), and amoxicillin/clavulanic (77% and 54%) respectively. Extended spectrum beta-lactamase (ESBL) resistance was present in 23% (71/315) vs. 35% (34/96) respectively. S. aureus susceptibility for methicillin was 99%. This antibiogram has shown that improvement in combination therapy is warranted in The Gambia.

Cumulative antimicrobial susceptibilities for respiratory clinical isolates of Mycobacterium avium Complex, Mycobacterium kansasii, and Mycobacterium abscessus from Pakistan 2018 to 2022.

Nontuberculous mycobacteria (NTM) are increasingly identified as causes of protracted pulmonary infections. Antibiotic susceptibility testing requires microdilution methods, which are often unavailable in laboratories in resource-poor settings. We report cumulative antibiograms for the most frequently isolated clinical pulmonary NTM from Pakistan to inform empiric antibiotic management of initial NTM infections. We analyzed data from 2018 to 2022 for the most frequently isolated and clinically relevant NTM isolated from respiratory specimens, i.e., Mycobacterium avium complex (MAC), Mycobacterium abscessus group (MAG), and Mycobacterium kansasii (MK). Antibiograms were developed using the Clinical Laboratory Standards Institute's M39ED5 standard. Percentage susceptibilities and 95% confidence intervals (CI) were calculated. Over 4 years, 529 NTM, comprising 209 MAC, 249 MAG, and 71 MK were analyzed. For MAC and MAG, where clarithromycin (CLR)-based regimens are recommended, CLR was active for 94.8% (95% CI 91.3-96.9), and 77.5% (95% CI 71.4-82.7) isolates, respectively. Combination regimens comprising 3 active drugs CLR + linezolid (LZD) + moxifloxacin for MAC and CLR + LZD + Amikacin for MAG had 98.4% (95% CI 95.9-99.4) and 68.9% (95% CI 62.3-74.8) coverage for pulmonary disease, respectively. For MK, 91.5% (95% CI 82.8-96.1) isolates were susceptible to rifampin (RIF), with a combination of RIF + CLR covering 88.7% (95% CI 79.3-94.2) of MK pulmonary infections, respectively. These data can inform empiric treatment guidance for the most common NTM pulmonary infections, i.e., for MAC, MAG, and MK disease in Pakistan.

Selective and Cascade Reporting of Antimicrobial Susceptibility Testing Results and Its Impact on Antimicrobial Resistance Surveillance-National Healthcare Safety Network, April 2020 to March 2021.

Selective or cascade reporting (SR/CR) of antimicrobial susceptibility testing (AST) results is a strategy for antimicrobial stewardship. SR/CR is often achieved by suppressing AST results of secondary drugs in electronic laboratory reports. We assessed the extent of SR/CR and its impact on cumulative antibiograms (CAs) in a large cohort of U.S. hospitals submitting AST data to the CDC's National Healthcare Safety Network (NHSN) through electronic data exchange. The NHSN calls for hospitals to extract AST data from their electronic systems. We analyzed the AST reported for Escherichia coli (blood and urine) and Staphylococcus aureus (blood and lower respiratory tract [LRT]) isolates from April 2020 to March 2021, used AST reporting patterns to assign SR/CR reporting status for hospitals, and compared their CAs. Sensitivity analyses were done to account for those potentially extracted complete data. At least 35% and 41% of the hospitals had AST data that were suppressed in more than 20% blood isolates for E. coli and S. aureus isolates, respectively. At least 63% (blood) and 50% (urine) routinely reported ciprofloxacin or levofloxacin for E. coli isolates; and 60% (blood) and 59% (LRT) routinely reported vancomycin for S. aureus isolates. The distribution of CAs for many agents differed between high SR/CR and low- or non-SR/CR hospitals. Hospitals struggled to obtain complete AST data through electronic data exchange because of data suppression. Use of SR/CR can bias CAs if incomplete data are used. Technical solutions are needed for extracting complete AST results for public health surveillance. IMPORTANCE This study is the first to assess the extent of using selective and/or cascade antimicrobial susceptibility reporting for antimicrobial stewardship among U.S. hospitals and its impact on cumulative antibiograms in the context of electronic data exchange for national antimicrobial resistance surveillance.

Impact of antimicrobial stewardship interventions on days of therapy and guideline adherence: A comparative point-prevalence survey assessment

BackgroundAntimicrobial stewardship (AMS) is a crucial tool for rationalizing the use of antimicrobial agents and reducing the burden of antimicrobial resistance. We aimed to assess the impact of AMS interventions on antimicrobial utilization and adherence to antimicrobial guidelines.MethodsWe conducted a prospective quasi-experimental study at a major tertiary hospital in the United Arab Emirates. Using standardized World Health Organization’s methodology, point-prevalence surveys (PPS) were performed in November 2019 and January 2022. Core AMS interventions consisted of proactive bloodstream infection service, proactive and reactive infectious diseases consult service, prospective audit and feedback by clinical pharmacists, development of antimicrobial guidelines based on cumulative antibiograms, and implementation of induction programs for new clinical staff. Days of therapy (DOT) per 1000 patient days present and rate of compliance with antimicrobial guidelines were compared before and after the core interventions. Multiple logistic regression analysis was carried out to adjust for the potential confounding effects of age, gender, hospitalization within 90 days, central or peripheral line insertion, urinary catheterization, and mechanical ventilation. P-value&amp;lt;0.05 was considered statistically significant.ResultsPre- and post-intervention PPSs included 292 and 370 patients, respectively. Both had similar age and gender distribution. Patients receiving antimicrobials were 51% (149/292) in 2019 and 45% (166/370) in 2022 (p 0.12). Univariate analysis showed a reduced post-intervention DOT per 1000 patients present (6.1 +/- 16.2 vs 2.4 +/-5.1, p&amp;lt;0.01) and an improved post-intervention guideline compliance (59% vs 67%, p 0.23). Following multiple logistic regression, the reduction in post-intervention DOT remained statistically significant (co-efficient -0.17 (95% CI -8.58 to -1.94, p&amp;lt;0.01), and the improvement in guideline adherence became statistically significant (adjusted odds ratio 1.91 (95% CI 1.05 to 3.45, p 0.03).ConclusionCoordinated and sustained AMS interventions have a significant impact on improving antimicrobial utilisation and adherence to guidelines.

Effects of empiric antibiotic treatment based on hospital cumulative antibiograms in patients with bacteraemic sepsis: a retrospective cohort study

ObjectivesTo assess the effects of empiric antibiotics with different degrees of appropriateness based on hospital cumulative antibiograms in patients with bacteraemic sepsis presenting to the emergency department (ED). MethodsThis retrospective cohort study included adult patients with sepsis and positive blood culture reports in the ED from February 2016 to December 2018. Based on isolated pathogens and empiric antibiotics which the patients received, these patients were divided into two groups using a cut-off of 70% for overall antimicrobial susceptibility (OAS) on hospital cumulative antibiograms 6 months prior to ED admission. Multivariate regression and sensitivity analyses were performed. ResultsIn this study, 1055 patients were included. We used multivariate regression models which were adjusted for age, sex, co-morbidities, site of infection, organ dysfunction, and septic shock. Empiric antibiotics with OAS of ≥70% were associated with reduced in-hospital deaths (adjusted odds ratio, 0.46; 95% CI, 0.28–0.77) and 30-day mortality (adjusted odds ratio, 0.53; 95% CI, 0.33–0.86). They were more likely to result in a shortened length of intensive care unit stay by 1.60 days (95% CI, −3.00 to −0.20). ConclusionsTreatment with empiric antibiotics with OAS of ≥70% based on hospital cumulative antibiograms is associated with lower mortality and shorter length of intensive care unit stay in patients with bacteraemic sepsis in the ED.

Estimated Impact of Low Isolate Numbers on the Reliability of Cumulative Antibiogram Data.

Antibiograms are cumulative reports of antimicrobial susceptibility results that are used to guide the selection of empirical antibiotic therapy. Although Clinical and Laboratory Standards Institute (CLSI) guidelines recommend including only organisms that have at least 30 isolates in an antibiogram, previous studies demonstrated that adherence to this recommendation is highly variable. This paper aims to model the impact of small sample sizes on expected levels of error in cumulative antibiograms by comparing percent susceptibility results for random samples to those of the larger, entire data set. The results demonstrate relatively high error rates when utilizing low numbers of isolates in cumulative antibiograms, and provide a discussion point for considering the appropriate number of isolates that could be utilized, and the impact of increasing isolate numbers by including multiple years of data. IMPORTANCE Antibiograms are reports of local antimicrobial susceptibility patterns for common bacteria and yeast that are used to make empirical decisions for patient therapy and also to inform institution therapy guidelines. This study evaluates the impact of low isolate counts on the reliability of antibiograms, and suggests that more institutions should utilize multiple years of data to overcome this issue.

Cumulative Antibiogram: A Rapid Method to Hinder Transmission of Resistant Bacteria to Oral Cavity of Newborn Babies.

A rapid bacterial diagnostic is needed more and more in the treatment of patients, because of the emergence of antibiotic resistance. The cumulative antibiogram, an annual report that monitors antimicrobial resistance trends in health care facilities, may provide a profile of empirical therapy useful in diverse emergency situations, such as transmission of resistant bacteria to oral cavity of newborn babies. We aimed to draw a profile of antibiotic resistance encountered. We assessed the antibiotic resistance (ABR) profile in childbearing women and newborn babies in Ploiesti Obstetrics and Gynecology Hospital by the disk diffusion method characterizing the multidrug-resistant organisms after isolation and identification by phenotypic tests. Extended-spectrum β-lactamase (ESBL)-producing Enterobacterales (ESBL-E), Carbapenem-resistant Enterobacterales (CRE), vancomycin-resistant Enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin resistant Group B Streptococcus (VR-GBS) were detected. The prevalence of antibiotic resistance was 11.32% (53/468), while the prevalence of the ESBL-E, MRSA, VRE and VR-GBS strains was 8.34% (39/468). Within the bacteria isolated from fifty-three childbearing women, the prevalence of ESBL-E, MRSA, VRE and VR-GBS was 22.64% (12/53), 32.08% (17/53), 11.32% (6/53) and 7.55% (4/53). In the whole studied group, the prevalence was 2.56% (12/468), 3.63% (17/468), 1.28% (6/468) and 0.86% (4/468). Resistant bacteria were detected at birth in the oral cavity of the newborn babies in all cases. Maternal and neonatal isolates shared similar characteristics. Cumulative antibiogram is useful in case of empiric treatment needed in diverse emergencies, such as transmission of resistant bacteria to oral cavity of newborn babies.

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

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. 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. 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. 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.

Tracking Annual Antimicrobial Resistance at a Tertiary Care Hospital amidst Raging COVID-19 Pandemic

Background: Timely preparation and presentation of the annual cumulative antibiogram play an important role in the dissemination of an updated susceptibility pattern to clinicians and thus aid in the appropriate choice of antimicrobials for empirical therapy while minimizing adverse effects and resistance. The study aimed to present and analyze the annual AMR data that may be helpful in designing antibiotic policy. Methods: All clinical specimens routinely submitted to the Department of Microbiology from January to December 2021 for bacteriological culture and antimicrobial susceptibility testing (AST) were included. AST was performed for pathogenic isolates by disc diffusion/agar dilution/broth microdilution methods/VITEK® 2 compact system. All data were entered and analyzed using WHONET 2020 software. Results: A total of 46,629 routine specimens were processed, yielding 5792 non-repeat bacterial isolates. Relatively fewer specimens were received during the first few months when the hospital catered exclusively to COVID-19 patients. The most common bacterial isolates were Escherichia coli (30%), Staphylococcus aureus (21%), Klebsiella sp. (18%), Pseudomonas sp. (10%), Acinetobacter sp. (8%) and Enterococcus sp. (5%). Analysis showed low susceptibility to 3rd generation cephalosporins, fluroquinolones, and cotrimoxazole among Gram negative bacteria. Less than 50% Acinetobacter sp. were carbapenem susceptible. We report high rate of methicillin resistance in S. aureus (74%). Overall susceptibility was much lower in specimens from ICU followed by in-patients and out-patients. Conclusion: Antimicrobial resistance is rapidly assuming the proportions of a pandemic, with several authors calling it “invisible” pandemic. As is evident from the present study, low susceptibilities to all but a few last-resort drugs are leaving few choices for treatment. This mandates effective preparation, distribution, and presentation of annual antibiograms, which will help in formulating hospital antibiotic policy.

In vitro susceptibility patterns for rapidly growing nontuberculous mycobacteria in the United States

Antimicrobial susceptibility testing for rapidly growing mycobacteria (RGM) is uncommon or only performed in large reference laboratories. Here we developed a cumulative antibiogram for 14 RGM using the largest sample size to date (N = 3860). All RGM showed 82% to 100% susceptibility to amikacin. Mycobacterium abscessus showed low percentages of susceptibility to most antimicrobials; of antimicrobials without interpretations, the minimum inhibitory concentration-90 for clofazimine was low (≤0.5mg/L). All three subspecies had ≤2.6% rrl resistance mutations, however intact erm(41) was detected in 70% to100% of M. abscessus abscessus and bolletii. Mycobacterium chelonae had a similar susceptibility pattern to M. abscessus subsp. massiliense and Mycobacterium immunogenum except that it was susceptible to tobramycin (87%). Mycobacterium fortuitum complex and similar organisms showed higher frequency of susceptibility to fluoroquinolones, beta-lactams, linezolid, and trimethoprim/sulfamethoxazole. Although relatively small published RGM antibiograms showed substantial variance, a comprehensive antibiogram can help influence treatment and monitoring patterns of resistance.

Utilising cumulative antibiogram data to enhance antibiotic stewardship capacity in the Cape Coast Teaching Hospital, Ghana

BackgroundAntimicrobial resistance (AMR) is a major public health challenge with its impact felt disproportionately in Western Sub-Saharan Africa. Routine microbiology investigations serve as a rich source of AMR monitoring and surveillance data. Geographical variations in susceptibility patterns necessitate regional and institutional tracking of resistance patterns to aid in tailored Antimicrobial Stewardship (AMS) interventions to improve antibiotic use in such settings. This study focused on developing a cumulative antibiogram of bacterial isolates from clinical samples at the Cape Coast Teaching Hospital (CCTH). This was ultimately to improve AMS by guiding empiric therapy.MethodsA hospital-based longitudinal study involving standard microbiological procedures was conducted from 1st January to 31st December 2020. Isolates from routine diagnostic aerobic cultures were identified by colony morphology, Gram staining, and conventional biochemical tests. Isolates were subjected to antibiotic susceptibility testing using Kirby-Bauer disc diffusion. Inhibitory zone diameters were interpreted per the Clinical and Laboratory Standards Institute guidelines and were entered and analysed on the WHONET software using the “first isolate only” principle.ResultsOverall, low to moderate susceptibility was observed in most pathogen-antibiotic combinations analysed in the study. Amikacin showed the highest susceptibility (86%, n = 537/626) against all Gram-negatives with ampicillin exhibiting the lowest (6%, n = 27/480). Among the Gram-positives, the highest susceptibilities were exhibited by gentamicin (78%, n = 124/159), with clindamycin having the lowest susceptibility (27%, n = 41/154). Among the Gram-negatives, 66% (n = 426/648) of the isolates were identified phenotypically as potential extended-spectrum beta-lactamase producers. Multiple multidrug-resistant isolates were also identified among both Gram-positive and Gram-negative isolates. Low to moderate susceptibility was found against first- and second-line antibiotics recommended in the National standard treatment guidelines (NSTG). Laboratory quality management deficiencies and a turnaround time of 3.4 days were the major AMS barriers identified.ConclusionsLow to moderate susceptibilities coupled with high rates of phenotypic resistance warrant tailoring NSTGs to fit local contexts within CCTH even after considering the biases in these results. The cumulative antibiogram proved a key AMS programme component after its communication to clinicians and subsequent monitoring of its influence on prescribing indicators. This should be adopted to enhance such programmes across the country.