JAC-Antimicrobial Resistance
◐ Oxford University Press (OUP)
Preprints posted in the last 90 days, ranked by how well they match JAC-Antimicrobial Resistance's content profile, based on 13 papers previously published here. The average preprint has a 0.02% match score for this journal, so anything above that is already an above-average fit.
Garpvall, K.; Aljundi, A.; Dahl, A.; Sterky, E.; Luthander, J.; Sutterlin, S.
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BackgroundElectronic prescribing registries are widely used for antimicrobial stewardship surveillance. Existing indicators predominantly measure structure or process, while validated outcome indicators remain rare. The present study evaluates how well rule-based measures capture clinically meaningful postdiagnostic antibiotic decision making in pediatric febrile urinary tract infection. MethodsWe conducted a retrospective, multicenter validation study including all empirically treated febrile UTI episodes across three Swedish pediatric emergency departments. Prescribing outcomes were classified using registry rules and compared with outcomes determined by clinician review and laboratory findings. Guidance Ratio (GR) and Discontinuation Ratio (DR) were calculated monthly and in aggregate for both clinically validated- and registry rule classifications. ResultsIn total, 909 febrile UTI episodes were included across all sites. The rule-based GR was 49%. GR increased consistently with stronger diagnostic evidence. Among the 431 episodes with clinician-adjudicated follow-up, 63% resulted in guided treatment; 28% discontinued treatment, and 9% lacked follow-up documentation. The rule-based algorithm showed a sensitivity of 0.78 and a specificity of 1.00 for identifying guided outcomes. Monthly rule-based GR tracked validated temporal patterns but underestimated absolute values. A calibration function substantially improved agreement. ConclusionsRule-based indicators captured overall prescribing patterns but underestimated the level of prescribing concordant with guidelines. Validation against clinician reviewed reference data enabled calibration and improved the interpretability of indicators based on registry data for antimicrobial stewardship.
Itani, D.; Philips, L. T.; Kotb Tolba, S.; Achour, W.; Smaoui, H.; Thabet, L.; Zribi, M.; Foster-Nyarko, E.; Holt, K. E.; Boutiba-Ben Boubaker, I.
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BackgroundAntimicrobial resistance (AMR) surveillance is essential for quantifying and monitoring the burden of AMR among World Health Organization (WHO) priority pathogens. We analysed Tunisian AMR surveillance system (TARSS) data across five sentinel hospitals from 2014 to 2022. MethodsWe conducted a retrospective isolate-level analysis for Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter spp. Temporal, ward, and specimen associations were quantified using multivariable logistic regression models. Sex and age categories were explored in secondary models due to missingness. Temporal trends were assessed using Cochran-Armitage test, and co-resistance was summarised for third-generation cephalosporin and carbapenem phenotypes. We also evaluated temporal dynamics of 3GCR and CR profiles. ResultsA total of 35,525 E. coli, 14,325 K. pneumoniae, 9,679 P. aeruginosa, and 5,597 Acinetobacter spp. were reported to TARSS between 2014 and 2022. Mean annual MDR prevalence was high for Acinetobacter spp. (85.1%), moderate for K. pneumoniae (45.5%) and for P. aeruginosa (27.1%), and lower for E. coli (17.5%). Adjusted models indicated increased odds of resistance to several antibiotics, whereas E. coli showed decreased odds. Intensive care unit (ICU) and blood isolates were associated with higher odds of resistance in all pathogens. ConclusionThis nine-year multi-hospital analysis reveals a high prevalence of AMR across the four WHO priority pathogens, settings, and specimen types, with increasing resistance for some pathogen-antibiotic combinations. The higher odds of clinically important resistance amongst ICU and blood isolates support the use of ward-level antibiograms and stratified stewardship and infection prevention measures.
Tsuzuki, S.; Koizumi, R.; Asai, Y.; Hashimoto, Y.; Inoue, N.; Ohmagari, N.
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Objectives: Optimising parenteral antimicrobial use is central to antimicrobial resistance (AMR) control, yet its appropriateness is difficult to assess. We aimed to develop a quantitative indicator to evaluate the appropriateness of parenteral antimicrobial therapy in hospitalised patients with bloodstream infections. Methods: We developed the Susceptibility-Spectrum Discrepancy Index (S2DI), reflecting the discrepancy between antimicrobial susceptibility of blood culture isolates and the spectrum width of prescribed agents. Using a database from 67 National Hospital Organization hospitals in Japan, we identified patients with Staphylococcus aureus or Escherichia coli bacteraemia from 2017 to 2023. An expert panel of 10 infectious disease physicians independently ranked antimicrobial susceptibility (A) and spectrum width of commonly used agents (B). S2DI was defined as B minus A on day 7 after treatment initiation, with values closer to zero indicating more appropriate therapy. S2DI was calculated for individual cases, aggregated at the hospital level, and analysed using linear mixed-effects models with hospital-level random effects. Results: A total of 4,505 S. aureus and 9,563 E. coli bacteraemia cases were included. Median S2DI was 1 (IQR 0-1) for S. aureus and 2 (IQR 0-3) for E. coli. For both pathogens, later calendar years were significantly associated with more favourable S2DI, suggesting gradual improvement in antimicrobial use. In E. coli bacteraemia, female sex and younger age were also associated with more appropriate therapy. Conclusions: Although variation across hospitals persists, appropriateness of parenteral antimicrobial use has improved over time. S2DI is a simple metric that may support optimisation of antimicrobial use.
Tom, I. M.; Ali, H. B.; Ibrahim, A. A.; Dutsinma, U. A.; Ibrahim, M. M.; Umoru, A. M.; Balla, H. J.
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BackgroundThe rise of antimicrobial resistance (AMR) in the Lake Chad Basin poses a significant threat to global health. While Escherichia coli and Klebsiella pneumoniae are primary concerns for the WHO, Proteus species have emerged as important clinical pathogens and potential reservoirs for genetic resistance. This study aimed to analyze the molecular diversity and horizontal gene transfer (HGT) potential of ESBL-producing Proteus species in the region. MethodsA regional surveillance was conducted with 1,500 clinical samples from Borno, Adamawa, Bauchi, Gombe, Taraba, and Yobe states. Proteus isolates were identified biochemically, and antibiotic susceptibility was assessed using the Kirby-Bauer method. Resistance genes (blaTEM, blaSHV, blaCTX-M) were identified via PCR, and HGT was evaluated through conjugation assays. ResultsA total of 144 Proteus isolates were identified, with a prevalence of 9.6%. P. mirabilis was the dominant species (90.97%). Phenotypic screening indicated that 69.44% produced extended-spectrum beta-lactamases (ESBL), with high resistance rates observed for Cefotaxime (80.56%) and Ampicillin (84.72%). Alarmingly, resistance to Ertapenem reached 54.86%. Molecular analysis showed blaTEM as the predominant gene (81.69%), and the conjugation assay revealed a high HGT rate of 76.92%, confirming blaTEM acquisition by E. coli. ConclusionThese results indicate that Proteus species in North-Eastern Nigeria are significant reservoirs for genetic resistance, facilitating the spread of ESBL markers. The high frequency of HGT raises concerns about the effectiveness of beta-lactam therapies in sub-Saharan Africa, underscoring the need to include Proteus in the GLASS framework and promote regional antimicrobial stewardship efforts. Current UnderstandingAntimicrobial resistance (AMR) in Enterobacteriaceae, particularly with Escherichia coli and Klebsiella pneumoniae, is a significant global issue highlighted by the World Health Organizations Global Antimicrobial Resistance and Use Surveillance System (WHO GLASS). While Proteus species are recognized as opportunistic pathogens, their role as genetic reservoirs in sub-Saharan Africa, especially in the Lake Chad Basin, remains inadequately defined in surveillance data. Study ContributionThis study identifies Proteus species as a critical "Genetic Hub" for the transmission of extended-spectrum beta-lactamases (ESBL) in North-Eastern Nigeria, revealing a high horizontal gene transfer (HGT) rate of 76.92% for the blaTEM genotype to E. coli. It also shows a concerning 54.86% resistance rate to Ertapenem, underscoring the urgent need to include Proteus in regional stewardship and global surveillance efforts.
Koudoum, P. L.; Ateudjieu, W. D.; Nana, A.; Guemkam, G. W.; Nditemeloung, G.; Abena, J. V.; Rene, E.; Vigny, N. N.; Joseph Magloire, T.; Mbossi, A. D.; Kamgno, J.; Kamga, H. G.
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Antimicrobial resistance (AMR) is classified by the World Health Organization (WHO) as one of humanity's ten global public health threats. This review aimed to estimate the prevalence, temporal trends and regional distribution of AMR in WHO priority bacteria across human, animal and environmental sources in Cameroon. This review was conducted following PRISMA 2020 guidelines, with the protocol registered in PROSPERO. A systematic literature search was conducted in Google Scholar, PubMed, African Journals Online, Hinari, and Africa indexus Medicus. Random effects models were used to estimate pooled prevalence and 95% confidence intervals (CIs), with subgroup analyses by bacterial source, region, and sampling period. Of 1566 articles screened, 115 met the inclusion criteria. The reported data encompassed 16 bacteria-antibiotic combinations in 16,948 isolates. Globally, third-generation cephalosporin (3GC) resistance in E. coli was the most prevalent (49.0%, 95% CI: 39.0-60.0%, I2=97.7%), reaching 77.0% (95% CI: 46.0-98.0%, I2=95.6%) in environmental isolates. The pooled prevalence of ESBL production in all included Enterobacterales was 37.0% (95% CI: 30.0-45.0%). Most of the highest resistance rates were observed in the Littoral region. The resistance rates between 2016 and 2025 were significantly higher than those from 2000 to 2015. These increases were more marked in fluoroquinolone-resistant Salmonella spp (1.0% to 48.0%, I2=97.3%, p<0.001), carbapenem-resistant E. coli (0% to 15%, I2=93.5%, p<0.001), and 3GC-resistant E. coli (34.0% to 64.0%, I2=97.6%, p=0.003). Antimicrobial resistance in WHO priority bacteria in Cameroon is high, unevenly distributed across regions and significantly increasing over time. These results underscore the crucial need for strengthened AMR surveillance to curb the growing threat of AMR in Cameroon.
Kyei, B. K.; Kyei, E. B.; Addo, M. Y.; Dugah, E.; Adu, C. A. T.; Yeboah, A.; Kumatia, A. B. A.
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The inappropriate use of antimicrobials enhances antimicrobial resistance (AMR). Antimicrobial stewardship (AMS) is a coordinated effort of prescribers, pharmacists, and nurses. Still, local data regarding AMS-related knowledge, attitudes, and practices (KAP) are scarce in many low and middle-income countries. We evaluated KAP regarding AMS among the healthcare providers at Komfo Anokye Teaching Hospital (KATH), Ghana, and found the related factors. A cross-sectional survey in the form of a descriptive survey was conducted among medical doctors, pharmacists, and nurses at KATH. Knowledge, attitude, and practice were evaluated using a structured questionnaire. The scores were converted into percentages and classified as good (>=60%) or poor (<60%). Chi-square tests were used to test associations, and logistic regression to predict good KAP (p<0.05). A total of 349 healthcare professionals participated, which comprised: 91 medical doctors (26.1%), 101 pharmacists (28.9%), and 157 nurses (45.0%). The majority of the respondents had formal AMS/AMR training (69.6%), and 37.0% had updated training the previous year. Only 18.6% demonstrated good AMS-related knowledge, although attitudes were largely positive (95.7% good) and reported practices were mostly appropriate (77.4% good). In multivariable models, greater years of practice (5-9 years: adjusted odds ratio [AOR] 2.32; >=15 years: AOR 2.77) and formal training (AOR 2.94) were associated with good knowledge. Formal training was also associated with good attitudes (AOR 5.19). Compared with medical doctors, nurses had lower odds of good practice (AOR 0.29), while pharmacists had higher odds (AOR 1.41). Participants with 10-14 years of experience had higher odds of good practice (AOR 3.18). This study revealed that marked knowledge deficits exist, despite favourable attitudes and generally good self-reported AMS practices. Role-tailored, competency-based AMS training with regular updates and reinforcement through practical stewardship tools is needed to translate positive attitudes into evidence-based prescribing and administration behaviours.
Gopichandran, V.; Muralidharan, N.; Chandrasekaran, J.; Sinthiya, D. D.; Subramaniam, S.; Thiagesan, R.; Ranjith, J.
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BackgroundUnderstanding antimicrobial use and factors driving it in communities is essential to devise its stewardship and reduce emergence of antimicrobial resistance. ObjectivesTo study the intersectional influence of socioeconomic status, migration and place of treatment on antimicrobial use in a semi urban area in Tamil Nadu, India. MethodsWe conducted a cross-sectional survey among systematically sampled 525 adult men and women from three villages in a semi-urban area in Tiruvallur district. We collected data through structured interviews on incidence of infections in the past 3 months, treatment seeking behaviour, and audited the antimicrobial prescription or empty packs of medicines used. We analyzed the data using R statistical software and performed a multilevel analysis of individual heterogeneity and discriminatory accuracy to study intersectional effects. ResultsWe found that the incidence of infection syndrome was 37% with a majority of them being acute respiratory infections. 143 of them sought treatment, with 40% going to a private general practitioner. People belonging to middle class had a 3.7 times greater odds of going to private sector compared to lower class. Twenty eight (19.6%) of those who sought treatment received an antimicrobial prescription. Sixty percent of them belonged to Access group, 35.7% Watch and 3.6% Restrict group. There was a significant intersectional effect showing middle class- non migrant - private care seekers having 22% probability of antimicrobial use versus lower class - migrant - government care seekers having 16% probability. The variance partition coefficient was 2.6% showing a small by significant portion of the variance contributed by intersectional identities. ConclusionAntimicrobial use in the community is significantly shaped by the intersection of socioeconomic status, migrant status and place of seeking care for the infection. Regulation of private sector prescription patterns and improving access to health care for migrants are key policy interventions.
Nguyen, P. Q.; Tran, G. V.; Nguyen, Y. H.; Pham, O. T. P.; Nguyen, C. T.; Vu, D. M.; Tran, C. A.; Nguyen, D. T. N.; Nguyen, M. V.; Mai, H. B.; Vo, D. B.; Nguyen, B. T.; Vu, P. D.; Pham, V. T. T.; Hoang, N. T. B.; van Doorn, H. R.; Kesteman, T.; Vu, H.
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Background Antimicrobial stewardship (AMS) and infection prevention and control (IPC) are complementary strategies to improve patient safety and address antimicrobial resistance (AMR). In low- and middle-income countries (LMICs), they are often implemented separately, reducing effectiveness. Evidence on integrating AMS and IPC in routine hospital practice remains limited. Objective To evaluate the feasibility of an integrated AMS-IPC improvement approach and describe changes in implementation in Vietnamese hospitals. Methods We conducted a multisite quality improvement initiative in four hospitals within the national AMR surveillance network in Viet Nam (March-September 2025). We used US-CDC tools to guide the implementation, including the Global Antibiotic Stewardship Evaluation Tool (G-ASET) and the Infection Control Assessment and Response (ICAR) tool. Baseline assessments were followed by feedback, multidisciplinary action planning, and targeted capacity building. Follow-up occurred 2-5 months later. Changes were analysed descriptively using quantitative scores and qualitative synthesis, and reported following the SQUIRE 2.0 guidelines. Results All hospitals had established IPC programmes at baseline, while AMS maturity varied. G-ASET scores improved across all sites, with greater gains in hospitals starting from lower baselines. Key improvements included leadership and governance, education and training, stewardship actions, and monitoring and reporting. IPC practices aligned with AMS priorities also improved, particularly transmission-based precautions, environmental cleaning, and cross-team coordination. Infrastructure-dependent areas, such as water safety, showed limited short-term progress. Conclusions An integrated AMS-IPC approach using repeated assessment and feedback is feasible and associated with meaningful improvements. This model offers a scalable strategy for strengthening hospital responses to AMR in LMICs and informs national programmes.
TANKPINOU ZOUMENOU, H.; Faucher, J.-F.
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BackgroundMetronidazole (MTZ) is a first-line antibiotic for several enteric infections. Its use is common in low-income countries, where most primary-care consultations are conducted by nurses. However, increasing resistance among some enteric pathogens is a growing concern. Using WHO guidelines, we conducted a register-based cross-sectional study to assess MTZ prescribing practices and their determinants in public and private primary healthcare facilities in South Benin. MethodsWe performed a register-based cross-sectional study covering the year 2020 in 11 primary healthcare facilities (5 public and 6 private) in Abomey-Calavi, South Benin, following WHO recommendations. In total, 200 visits per facility were selected using systematic random sampling. The primary outcome was the prevalence of MTZ prescription. Determinants of MTZ prescription were identified using multivariable logistic regression analysis. ResultsIn total, 2,200 medical visits were analyzed. The median age of patients was 19 years, and 57% were female. Antimalarials were prescribed in 52% of visits. Antibacterial agents were prescribed in the majority of visits, with MTZ being the second most frequently prescribed antibiotic (18%), after aminopenicillins (27%). In multivariable analysis, digestive symptoms (adjusted odds ratio [aOR], 8.65; 95% confidence interval [CI], 6.49-11.6), genitourinary symptoms (aOR, 6.84; 95% CI, 3.18-15.0), and skin lesions (aOR, 2.39; 95% CI, 1.58-3.60) were independently associated with increased odds of MTZ prescription. In contrast, fever (aOR, 0.66; 95% CI, 0.49-0.87), respiratory symptoms (aOR, 0.44; 95% CI, 0.26-0.71), and malaria (aOR, 0.21; 95% CI, 0.15-0.28) were associated with decreased odds. Visits in the private sector were also associated with higher odds of MTZ prescription compared with the public sector (aOR, 2.31; 95% CI, 1.78-3.02). ConclusionMTZ is the second most commonly prescribed antibiotic in primary care in the study area, with its use largely driven by digestive symptoms. Further studies are needed to assess the appropriateness of this prescription. Additionally, research is warranted to understand better the determinants of higher antimicrobial prescribing in the private healthcare sector. Highlights- MTZ is the second most prescribed antibiotic in the study area. - MTZ prescription is primarily driven by digestive symptoms. - The private healthcare sector is independently associated with higher MTZ prescription rates. - Antimicrobial prescribing is generally higher in private healthcare facilities than in public facilities.
BHADRA, S.; Gaikwad, U.; Vikram, K.; Chandrakar, S.; Prasad, A.
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BackgroundMoxifloxacin is a key component of current MDR-TB therapy regimens. The choice to include it in therapy at standard or higher doses is based on the lack or presence of resistance mutations conferring low-level or high-level resistance to moxifloxacin, as detected by the Line probe assay (LPA). Due to inherent phenotypic and genotypic discordance, such resistance must be reconfirmed phenotypically using liquid culture and drug susceptibility testing (LC-DST) at critical concentration and clinical breakpoint of the drug. This takes several weeks, delaying the therapeutic decision. The current study intends to shorten this time by performing phenotypic DST directly on sputum samples. MethodsA cross-sectional study was conducted for 18 months from October 2023 to April 2025, in which smear positive sputum samples that were resistant to Rifampicin or Isoniazid or both were subjected to Direct Moxifloxacin DST, irrespective of patient characteristics. Results obtained by Direct DST were compared against Indirect LC-DST as the gold standard as well as with LPA to evaluate the diagnostic accuracy and time savings with direct DST. ResultsDirect DST exhibited high accuracy of 98.18%, high sensitivity (90.91%), high specificity (98.99%), excellent concordance (98.18%) and almost perfect agreement (kappa value - 0.901) when compared to Indirect DST. It saved an average of 10 {+/-} 3.20 days over Indirect DST to obtain the valid results. Similar performance was also observed in comparison to LPA with good sensitivity (90.91%), specificity (98.99%) and accuracy (98.18%). Significant discordance was however noted in classification of resistance by both direct and indirect DST compared to LPA. Few error rates and minimal cost advantages were some of the disadvantages of Direct-DST. ConclusionDirect DST demonstrated excellent performance characteristics, making it a reliable and rapid alternative to the gold standard, saving significant time in guiding therapeutic decisions for effective patient management.
Van Benten, K. R.; Cooper, L.; Kirby, K.; Kruer, S.; Byron, K.
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BACKGROUNDAutomated antimicrobial susceptibility testing (AST) systems are crucial for accurate, timely detection of drug-resistant microbial isolates. This meta-analysis assessed the performance of the BD Phoenix ("Phoenix", BD Diagnostic Solutions), Vitek(R) 2 ("Vitek 2", bioMerieux), and DxM MicroScan WalkAway ("MicroScan", Beckman Coulter, Inc.) AST systems relative to common reference methodology. METHODSA systematic literature search in Ovid (MEDLINE and Embase) yielded 275 unique (not duplicated) records, with 44 additional records retrieved from handsearching; 39 studies met inclusion criteria. Categorical agreement (CA), essential agreement (EA), very major errors (VMEs), and major errors (MEs) for the three instruments were compared to a common reference method. Ratios of proportions were analyzed using random-effect meta-regression. RESULTSThe instruments did not differ significantly in CA, EA, or ME. Vitek 2 showed a higher overall VME rate than Phoenix ([~]44% higher; Vitek 2-to-Phoenix ratio = 1.44; p=0.062 [approaching significance]) and MicroScan (74% higher; ratio = 1.74; p=0.045). No appreciable difference was observed for VME between Phoenix and MicroScan. Subgroup analyses should be interpreted cautiously due to limited overall significance indicating varying performance across systems. Vitek 2 generally had higher relative VMEs for gram-negative organisms and lower relative VMEs for gram-positive organisms, whereas Phoenix showed the opposite pattern. MicroScan had relatively low VMEs when stratified by Clinical and Laboratory Standards Institute (CLSI) criteria; no differences in VMEs were observed using European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria. CONCLUSIONAlthough some VME differences were noted, overall performance of the three systems was comparable. Organism- and drug-specific VME patterns--and updates to CLSI criteria over time--highlight the importance of continued monitoring of current breakpoints for all three instruments.
Huse, H. K.; Manuel, C.; McLemore, T.; Humphries, R. M.; Milesi Galdino, A. C.; Celedonio, D.; LiPuma, J. J.; Green, D. A.; Zlosnik, J. E. A.; Traczewski, M. M.; Schuetz, A. N.; Turnidge, J. D.; Wootton, M.; Carpenter, D.; Huband, M. D.; Pillar, C. M.; Monogue, M. L.; Jorth, P.
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The Burkholderia cepacia complex (BCC) is comprised of 24 species of Gram-negative bacteria that cause opportunistic infections. While antimicrobial susceptibility testing (AST) has historically been used to guide treatment for BCC infections, recent work highlighting problems with AST for these organisms led the Clinical and Laboratory Sciences Institute (CLSI) to remove disk diffusion (DD) and minimal inhibitory concentration (MIC) breakpoints for BCC from its M100 standards document. Epidemiological cut-off values (ECVs) may be helpful to clinicians in the absence of breakpoints, as they may be used to determine whether an isolate has a wild-type or non-wild-type phenotype. Here we present an analysis of BCC ECVs for ceftazidime (CAZ), levofloxacin (LVX), meropenem (MEM), minocycline (MIN), and trimethoprim-sulfamethoxazole (TMP-SMX). ECVs were calculated using MIC data from 3 previous studies and 3 independent laboratories for 1,896 BCC isolates. ECVs were 16 g/ml for CAZ, 8 g/ml for LVX, 16 g/ml for MEM, and 8 g/ml for MIN. The ECV for TMP-SMX varied depending on the analysis from 2 g/ml, 8 g/ml, and 16 g/ml and therefore could not be reliably established. Challenges with establishing ECVs for BCC include limitations with the pooled MIC dataset, broad MIC distributions, and high ECVs that are above the obsolete susceptible MIC breakpoints. These challenges limit the clinical utility of ECVs for these organisms and supported removal of ECVs from the CLSI M100 standards document. IMPORTANCEThe Burkholderia cepacia complex is a group of bacterial species that cause difficult-to-treat opportunistic infections. Recently, clinical breakpoints, which are used to determine whether organisms are susceptible to certain antimicrobials, were removed from Clinical and Laboratory Standards Institute (CLSI) standards for these organisms due to problems with antimicrobial susceptibility testing performance. Clinicians are now faced with the challenge of how to treat these complex infections without clinical breakpoints. Here we determine epidemiological cut-off values (ECVs) for relevant antimicrobials for the B. cepacia complex. While we established ECVs for four antimicrobials, we encountered significant challenges in our analyses, including limitations with data for these organisms and high ECVs that are not clinically useful. These challenges limit the practical use of these ECVs in helping guide clinicians on treatment and supported the eventual removal of ECVs from the CLSI M100 standards document.
MWABU, A. K.; Mutai, W. C.; Jaoko, W.; Mwaniki, J. N.; kiiru, J. N.
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Introduction: Antibiotic misuse is a major driver of antimicrobial resistance (AMR), contributing to an estimated 1.27 million deaths globally. In Kenya, inappropriate antibiotic use is shaped by health-seeking behaviors and sociodemographic factors. However, little is known about how adults with productive coughs seek and use antibiotics, or how sociodemographic factors underpin these practices. This study explored antibiotic-seeking pathways, usage patterns, and the sociodemographic factors influencing these practices among adults with productive coughs attending selected chest and tuberculosis clinics in Nairobi County, Kenya. Methodology: A facility-based cross-sectional study was conducted among 400 adults ([≥]18 years) with productive coughs. Data were collected using a structured questionnaire on sociodemographic characteristics, antibiotic-seeking pathways, and use patterns. Results: Most participants were male (65.0%) and employed (67.0%), with 68.3% earning below Ksh 10,000 (approximately USD 80) monthly and 35.8% having basic education. A history of smoking (37.3%), tuberculosis (32.0%), or other comorbidities (29.8%) was common. Among 347 (86.7%) antibiotic users, 46.4% obtained antibiotics through general practitioners (GP) only, 31.4% via both GP and over-the-counter (OTC) sources, 15.3% from OTC only, and 6.9% through self-medication. Females were more likely to self-medicate (13.3% vs. 3.2%) and had higher odds of antibiotic use (cOR: 2.00; 95% CI: 1.04-4.10). Tuberculosis history was linked to greater GP reliance (61.7% vs. 37.4%). Low-income participants mainly used GP-only sources, while higher-income earners favored GP plus OTC routes (RRR: 2.67; 95% CI: 1.41-5.05). Empirical use was common (71.1%), dominated by Amoxicillin (90.8%), with multiple antibiotic use reported by 67.2% of the participants. Conclusion: Antibiotic use among adults with productive coughs in Nairobi was widespread and largely empirical, dominated by Amoxicillin and Amoxicillin/Clavulanic acid. Self-medication, unregulated antibiotic access, and inappropriate use highlight the urgent need for stricter prescription enforcement and strengthened stewardship programs to promote rational antibiotic use and curb AMR.
Nyang'wa, B.-T. B.; Motta, I.; Moodliar, R.; Solodovnikova, V.; Rajaram, S.; Rasool, M.; Berry, C.; Moore, D. A. J.; Davies, G.; Kloprogge, F.
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WHO recommends bedaquiline-pretomanid-linezolid- (BPaL) and BPaL-moxifloxacin (BPaLM) for treatment of rifampicin-resistant tuberculosis, informed by the TB-PRACTECAL results. However, clinical explanatory data of these drugs exposure and Mycobacterium tuberculosis clearance rates and toxicity relationships remain understudied. We therefore investigated the relationship between the patients exposure to anti-TB drugs in TB-PRACTECAL trial investigational regimens and their treatment outcomes. PRACTECAL-PKPD was a prospective pharmacokinetics and pharmacodynamics study nested in TB-PRACTECAL. Patients with rifampicin-resistant pulmonary tuberculosis were enrolled from Belarus and South Africa. The first objective was to develop drug exposure metrics for bedaquiline, pretomanid, linezolid, moxifloxacin and clofazimine. The efficacy objectives were to establish an exposure-response model for each drug and regimen to both bactericidal activity and long-term treatment outcomes. The safety objective was to investigate the exposure-toxicity relationship of each drug. Antimicrobial exposure did not correlate with the speed of sputum bacterial clearance, however there was a 20% increased bacillary killing rate with BPaLM compared to the standard of care arm whilst BPaL and BPaL-clofazimine (BPaLC) displayed a 15% decreased bacillary killing rate compared to the standard of care arm. Linezolid plasma exposure was higher amongst patients with anaemia or neutropenia compared to those without. No other exposure-toxicity relationships were identified for all other drugs. Absence of correlation between drug exposure and bacillary clearance suggest that the dosages used achieve saturation of bacillary killing, while remaining safe.
Tesfaye Guteta, E.; Diriba, A.; Tesfaye, K.; Kedir, E.; Wakgari, M.; Jabessa, D.; Chali, M.; Biyena, K.; Sileshi, G.; Jobir, G.
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From 2021 to 2025, MRSA emerged as a major multidrug-resistant pathogen in the study area. Among 545 S. aureus isolates, 67.2% were MRSA, disproportionately affecting children under five (26.5%) and males (55.5%). Case incidence more than doubled by 2025, suggesting rising transmission or resistance. Most isolates were hospital-associated (85.2%), predominantly from outpatients (88.5%), with middle ear discharge as the main source (67%). Gentamicin showed the highest susceptibility (72.1%), while penicillin G resistance was nearly universal (96.7%). The majority (93.4%) were multidrug-resistant, with high MARI values indicating widespread and likely inappropriate antibiotic use. These findings reflect a complex interplay between pathogen behavior, antimicrobial use, and healthcare practices. Increasing MRSA burden may stem from inadequate infection control, poor stewardship, or enhanced community transmission. Incorporating molecular typing could deepen understanding of strain diversity and resistance mechanisms to guide targeted interventions ImportanceTo address scarce antimicrobial resistance data undermining patient care, this first multicenter study maps MRSA susceptibility in Western Ethiopia. Findings guide empiric therapy, establish a stewardship baseline, and contribute to global surveillance. Widespread multidrug resistance and high resistance indices reflect strong antimicrobial pressure and misuse, underscoring the urgent need for antimicrobial stewardship, surveillance, and infection control.
Gallardo Mejia, A.; Almeida, J.
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Urinary tract infections (UTIs) are among the most common infectious diseases worldwide, with Escherichia coli being the predominant uropathogen. The increasing prevalence of extended-spectrum beta-lactamase (ESBL)-producing strains and their association with fluoroquinolone resistance pose a significant challenge to empirical therapy, particularly in community settings. The aim of this study was to determine the epidemiology and predictive factors associated with ESBL-producing E. coli and its concomitant fluoroquinolone resistance in community-acquired clinical isolates. A retrospective cross-sectional study was conducted analyzing 244 clinical E. coli isolates. Demographic and microbiological data were collected, including age, sex, sample type, and antibiotic susceptibility. Associations between variables and ESBL production were assessed using Pearsons chi-squared test, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Of the isolates, 165 (68%) were ESBL-producing. A significant association was observed between age group and ESBL production (p < 0.001), with the highest frequency in the 20-39 age group. Most ESBL-positive isolates were obtained from women (73%), although odds ratio (OR) analysis suggested a non-significant trend toward a higher probability in men (OR = 1.29; 95% CI: 0.72-2.31). High rates of fluoroquinolone resistance were identified among the ESBL-producing isolates, with 30% resistance to levofloxacin and 35% to ciprofloxacin (p < 0.001). Urine samples showed the highest concentration of ESBL-positive isolates, with a significant association between sample type and resistance (p < 0.001). The high prevalence of ESBL-producing E. coli and its concomitant resistance to fluoroquinolones highlight a critical challenge for the empirical treatment of urinary tract infections in Mexico, underscoring the need to strengthen antimicrobial use management and local surveillance strategies.
Walaskar, S.; Jathar, P.; Mohapatra, P.; Chandrasingh, S.; George, C. E.; Rachannavar, Y.; Mishra, R.; MALIK, M. R.
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BackgroundRapid identification of pathogens and antimicrobial resistance (AMR) in bloodstream infections (BSIs) is critical for timely clinical management. Although blood culture is the reference standard, it is limited by turnaround time and incomplete resolution of resistance mechanisms. We evaluated metagenomic next-generation sequencing (mNGS) applied to flagged positive blood culture bottles to enhance diagnostic resolution and inform targeted molecular approaches. MethodsFifty-five flagged positive blood culture bottles from a tertiary care hospital in Bengaluru, India, were analyzed. Shotgun mNGS was performed directly on blood culture broth and compared with routine phenotypic identification and antimicrobial susceptibility testing (AST) from corresponding isolates. Antimicrobial resistance genes (ARGs) and plasmid replicons were profiled. ResultsmNGS showed high concordance with routine culture for pathogen identification (54/55; 98.2%) and improved species-level resolution across bacterial and fungal pathogens. Genotypic resistance profiles were consistent with phenotypic AST, identifying {beta}-lactamases, efflux-associated determinants, and target modification mechanisms. Diverse ARGs and plasmid replicons (Inc-, Col-, and rep-family) were detected, providing genomic context for resistance. Sequencing predominantly reflected the cultured organism, supporting high specificity in flagged blood culture material. ConclusionsmNGS applied to flagged blood culture bottles enables high-resolution characterization of pathogens and resistance determinants at a clinically actionable stage. The genomic insights generated provide a framework for developing targeted multiplex PCR assays that can reduce turnaround time and improve affordability compared with sequencing-based approaches. This strategy supports the use of mNGS as an adjunct to conventional diagnostics and as a bridge toward scalable, rapid, and cost-effective solutions for BSI diagnosis and AMR surveillance.
Chhabra, S.; Nair, S.; Bramley, A.; Chee, J. Y.; Vignesvaran, K.; See, D. R. E.; Sun, L. J.; Ching, A. H.; Li,, A. Y.; Kayastha, G.; Chetchotisakd, P.; Cooper, B. S.; Charani, E.; Mo, Y.
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Background Antibiotic use is prevalent in hospitals, driving the emergence of drug-resistant pathogens. We investigated the contextual influences on antibiotic prescribing behaviour across hospitals in high, middle, and low-income countries in Asia with an aim to provide actionable insights to improve prescribing behaviour. Methods We conducted a large qualitative study across ten institutions in Singapore, Nepal, and Thailand. Semi-structured interviews and ethnographic observations involving physicians, nurses, pharmacists, and management staff were conducted. Data were analysed thematically using QSR NVivo 14. Findings A total of 194 interviews were conducted amongst physicians (54{middle dot}1%), nurses (19{middle dot}6%), pharmacists (12{middle dot}4%), and management staff (13{middle dot}9%). Structural factors such as limited microbiology laboratory capabilities, concerns about antibiotic quality, weak infection prevention and control policies, and the lack of relevant, updated guidelines were prominent drivers for prolonged and broad-spectrum antibiotics prescriptions. Where these system supports were in place, prescribing decisions were less defensive and more targeted, although prescriber responsibility and concerns about immediate patient deterioration continued to influence practice. Across settings, clinicians tended to prioritise short-term perceived benefits of antibiotic treatment over the longer-term risks of antimicrobial resistance.
Freeouf, S.; Palethorpe, S.; Fairhead, C.; Kewcharoenwong, C.; Khemla, S.; Wiboonsuntie, N.; Juhongf, S.; Wren, B.; Edwards, T.; Lertmemongkolchai, G.; Brown, J.
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Objectives: To better define the clinical features of Acinetobacter spp. infection in Northern Thailand, including a comparison of hospital- and community-acquired infections (HAIs and CAIs). Methods: A prospective clinical study of Acinetobacter spp. infections at two Northern Thailand hospitals from 2019 to 2022, collecting data on sample sources, patient demographics, comorbidities, antimicrobial resistance profiles, and outcomes. Results: Of 129 enrolled patients, 81.4% had Acinetobacter spp. isolated from a respiratory sample. A significant minority (25.6%) of infections were CAIs, 33.3% of which were admitted to ITU within 24 hours of admission. Compared to HAIs, CAIs were significantly more likely to be caused by blood (15.2%, p=0.0258), wound (21.2%, p=0.0120), or urine infections (12.1%, p=0.0370). Acinetobacter spp. HAIs mainly occurred after admission to ITU (87.7%, p<0.0001) and were more likely to be multidrug-resistant than CAIs (76.3% vs. 34.4%, p<0.0001). Overall, the median length of hospital stay was 27 days and there was a 27.1% in-hospital mortality, which was increased in patients with CVA/brain (p=0.005), and multidrug-resistant (p=0.010) or carbapenem-resistant infections (p=0.003). Conclusions: These data define the clinical profile of Acinetobacter spp. infections in Northern Thailand, confirming their high mortality and demonstrating CAIs are a significant proportion of all cases.
DIXIT, S.
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IntroductionAcinetobacter is a highly diverse genus which includes a range of common pathogenic species such as A. baumannii, A. lwoffii etc. Acinetobacter species causes bacteremia, pneumonia, wound infections, Urinary tract infections in community as well as hospital settings. A. baumannii is one of the ESKAPE pathogen which makes it even more lethal as antibiotics cannot action on this. AimTo isolate Acinetobacter species from various clinical samples and to check their antimicrobial susceptibility pattern by VITEK {square} Compact in SGT Hospital, Gururam, Haryana. ResultsOut of total 6673 samples 595 were the positive isolates from which 35 were Acinetobacter isolates which were received from various wards of the hospital. Occurrence of Acinetobacter was seen more in males(57.14%) as compare to females (46.8%). A total of 31 strains were A. baumannii, 3 were A. lwoffi and 1 strain was of A. haemolyticus. Prominent presence of Acinetobacter was seen in Blood (48.57%) specimen along with pus(22.85%), endotracheal (22.85%), tracheal (2.85%) and eye swabs (2.85%). All the isolates were resistant to piperacillin/tazobactam (100%), ceftriazone (100%), amikacin (100%), gentamicin (100%) ciprofloxacin (91.42%), ceftazidime (91.42%), cefepime (88.57%), levofloxacin (88.57%) and trimethoprim/sulfamethoxazole (80%). Colistin susceptibility was observed in 88.57% of the isolates. ConclusionAcinetobacter is a common pathogen in hospital acquired as well as in community acquired infections as it is a opportunistic pathogen hence to identify the Acinetobacter species and to understand their antimicrobial resistance pattern this study was conducted.