While surgical antibiotic prophylaxis (SAP) is a cornerstone of preventing surgical site infections, adherence to clinical guidelines determines its effectiveness. In Spain, nationwide data on SAP appropriateness are scarce. This study evaluated prescribing practices across Spanish hospitals to assess alignment with national standards and identify factors associated with inappropriate antibiotic use.

Bovine mastitis (BM) is a leading cause of economic loss in the dairy industry, driven by decreased milk yields, involuntary culling, and substantial veterinary costs. A single Gram-negative isolate recovered from BM was characterized in this study. For this, antimicrobial susceptibility testing (AST) was performed using the Neg-Urine-Combo 98 panel. Whole-genome sequencing (WGS) was employed to identify antimicrobial resistance genes (ARG), virulence factors (VF) genes, plasmid replicons and prophage sequences. Comparative genomic analysis was performed through phylogenetic analysis. The BM isolate was phenotypically identified as Citrobacter rodentium, however, WGS analysis reclassified the isolate as Enterobacter oligotrophicus. Phenotypic AST revealed a resistance profile of 12%, with the isolate exhibiting resistance to β-lactams antimicrobials, specifically amoxicillin-clavulanate, ampicillin and the cephalosporin-cefoxitin. Conversely, susceptibility was demonstrated for the remaining tested antimicrobials. Genomic profiling identified 31 ARG, 10 VF genes and 6 prophage sequences within the E. oligotrophicus genome. This study provides the first evidence of E. oligotrophicus as a causative agent of BM, expanding the known spectrum of pathogens affecting the dairy industry by delivering the second complete genome of E. oligotrophicus available globally. The identification of 31 ARG, 10 VF, and 6 prophage sequences underscore the potential pathogenic risk and environmental resilience of this isolate. These findings highlight the critical role of WGS-based surveillance in identifying non-conventional mastitis pathogens and underscore the need for targeted mitigation strategies in veterinary medicine.

This study examined the prevalence, molecular characterization, and antimicrobial resistance of Escherichia coli associated with the bovine clinical mastitis in the northern part of Bangladesh. A total of 120 milk samples from infected cows in Dinajpur, Thakurgaon, and Nilphamari were collected. General bacteriological and biochemical tests were conducted to isolate and identify the bacteria. In addition, PCR assays were performed to molecularly detect and identify virulence and antibiotic resistance genes. Bacteriological, biochemical, and molecular methods confirmed the presence of E. coli, which constituted a total prevalence of 35.0%. Phylogenetic typing revealed two types, A1 (81.0%), and B2 (19.0%) (p < 0.001), suggesting that commensal strains predominating the total E. coli population. Virulence gene (eae, stx1, and stx2) screening was negative, indicating a lack of classical enteropathogenic/enterohemorrhagic characteristics. Antibiotic susceptibility testing showed that the level of antibiotic resistance was high, especially to ampicillin (100.0%), amoxicillin (92.86%), tetracycline (73.81%), erythromycin (61.91%), streptomycin (59.53%), and gentamicin (52.38%). The isolates were mostly sensitive to ceftriaxone (85.71%) and moderately sensitive to chloramphenicol and ciprofloxacin. The most abundant resistance gene was tetA (85.71%), followed by sul2 (59.52%), blaTEM (57.14%), aadA1 (50.0%), qnr (23.80%), and blaCTX-M (19.04%) (p < 0.001), which are strongly connected to the phenotypic resistance pattern. In general, the results indicate that highly resistant E. coli are prevalent in the case of bovine mastitis, which highlights the necessity to use antibiotics reasonably, conduct more frequent monitoring, and use biosecurity to limit the spread of resistant pathogens in the dairy industry, as well as the environment.

To determine the proportion of children labelled as allergic to amoxicillin who are truly allergic and to assess whether a direct oral amoxicillin challenge, without prior skin testing, is a safe and effective way to remove incorrect allergy labels in low-risk pediatric patients in Northwestern Ontario. We conducted a retrospective review of pediatric patients (6 months-15 years) referred for suspected amoxicillin allergy at two Northwestern Ontario hospitals between 2015 and 2025. Eligible patients underwent oral amoxicillin challenge. Clinical data were summarized descriptively. Of 96 patients, 93 (96.9%) tolerated the oral amoxicillin challenge, while 3 (3.1%) developed mild, delayed rashes. All three had previously reported delayed reactions (5-10 days) after their initial amoxicillin exposure. Two patients developed delayed rashes that were consistent with their previously documented maculopapular reactions, based on EMR documentation and caregiver-reported descriptions.Conclusion: The prevalence of true amoxicillin allergy among low-risk pediatric patients carrying a reported "penicillin allergy" label in our cohort of 96 patients evaluated at our pediatric allergy clinics in Northwestern Ontario was 3.1%. Oral amoxicillin challenge without prior skin testing proved to be a safe and effective approach for delabelling low-risk children. Broader implementation of this strategy could enhance antibiotic stewardship, reduce healthcare-related costs, and improve patient care.

BackgroundStevens-Johnson Syndrome (SJS) is a rare and severe drug-induced cutaneous reaction. However, clinical and economic data regarding its management remain poorly documented in Gabon. Therefore, this study aimed to describe the clinical characteristics, drug causality assessment, therapeutic management, and direct medical costs of four confirmed cases of SJS managed at the Libreville University Hospital Center (CHUL).Case reportFour confirmed cases of SJS related respectively to lidocaine, allopurinol, amoxicillin/clavulanic acid, and flucloxacillin were identified. Drug causality assessment, performed using the French causality assessment method, the World Health Organization (WHO) scale, and the ALDEN algorithm, indicated a probable causal relationship in all cases. SCORTEN scores ranged from 0 to 1, corresponding to an estimated mortality rate of 3.2%. Therapeutic management was based on symptomatic and supportive treatment, including Polaramine, Solumedrol, Dacryoserum, eosin solution, Fucithalmic, sodium bicarbonate, Fungizone, Dexeryl, ciprofloxacin, and Exomuc, with favorable clinical outcomes observed in all patients. The mean direct medical cost of management was estimated at 225,089 CFA francs (343.14 €), with a total cost of 860,355 CFA francs (1311.60 €) for the four cases.ConclusionSJS remains a severe dermatological emergency associated with substantial management costs despite favorable clinical outcomes. These findings highlight the importance of strengthening pharmacovigilance activities and the prevention of serious adverse drug reactions.

The intensification of worldwide urbanization and industrial growth has led to a rise in the release of toxic substances into the environment. Antibiotics are widely used as human medicine and animal husbandry, for example annual global consumption (106 kg) of amoxicillin is 11.8, sulfamethoxazole is 2.0, tetracycline is 0.5 and spiramycin is 0.3 etc., therefore, they are often found in surface water and wastewater, thus possess a threat both to human and eco health. Photocatalytic technology can efficiently eliminate highly hazardous, low-concentration, and hard-to-treat contaminant, and tungsten trioxide (WO3) serves as a highly promising alternative photocatalyst. Evaluating the effectiveness of WO3 in photocatalytic decomposition through traditional techniques is resource intensive and complex. Consequently, in this study experimental results are applied for modeling and optimizing the operational parameters on photocatalytic decomposition of spiramycin, an emerging antibiotic contaminant using WO3 as photocatalyst. Three experimental parameters (photoreactor solution pH, WO3 concentration and spiramycin (SPR) initial concentration) were chosen to gather preliminary information. The influencing interaction effects and optimal parameters values were determined by using a machine learning technique of XGBoost employing a data set of 45 dataset points obtained under 3 parametric effects. The model achieved an R2 value of 0.983 and 0.992 on test and training data, respectively. SHAP (SHapley Additive exPlanations) analysis was utilized to elucidate the prediction outcomes, uncovering the importance and influence patterns of the input parameters. The degradation rate of SPR approached ~87.6% under optimal conditions of pH value of 5.0, WO3 concentration of 0.125g/l and pollutant concentration of 0.15 g/l, respectively. In addition, the applied ML method revealed that the most influencing parameter is the reactor solution pH value followed by pollutant concentration on the decomposition of SPR antibiotic. Moreover, we conducted experiments to investigate the role of oxidizing species. Our findings indicate that primarily hydroxyl radicals (OH•) followed by photoinduced holes (h+s) and hydrogen peroxide (H2O2), play significant roles in the breakdown of model contaminant. We also studied the reaction kinetics and proposed the photocatalytic mechanism based on the obtained results. As a study outcome, the XGBoost model exhibits great accuracy and strength, suggesting that machine learning holds considerable practical promise and worth in forecasting the degradation emerging pollutants via photocatalysts.

The rise of multidrug-resistant microorganisms highlights the need for rapid antimicrobial susceptibility testing (AST) to guide early and effective therapy. This study evaluated a novel MALDI-TOF MS-based assay (MBT FAST, Bruker, Germany), which employs the direct-on-target microdroplet growth assay (DOT-MGA) for phenotypic AST. A total of 243 Enterobacteriaceae isolates representing diverse species and resistance patterns were tested against a broad panel of antibiotics. Each isolate was incubated in 6-µL microdroplets of cation-adjusted Mueller-Hinton broth, with and without antibiotics at two-fold serial dilutions, at 35°C for 6 h inside a humidity-controlled chamber (MBT FAST Shuttle, Bruker). Broth was removed using a prototype device (MBT FAST Stamp, Bruker), and MALDI-TOF MS measurements were performed with the MALDI Biotyper Sirius system (Bruker). Results were compared with broth microdilution as the standard for determining minimum inhibitory concentrations (MIC). Valid growth control was achieved for 100% of isolates. Essential agreement (EA), defined as MICs within ±1 two-fold dilution step of the standard method, was as follows: amoxicillin/clavulanic acid 96.3%, amikacin 97.5%, aztreonam 95.5%, ceftazidime/avibactam 95.5%, ceftazidime 94.6%, cefepime 92.2%, ciprofloxacin 91.8%, colistin 92.2%, ceftriaxone 95.5%, cefotaxime 94.2%, gentamicin 95.5%, imipenem 91.8%, levofloxacin 97.9%, meropenem 87.2%, meropenem/vaborbactam 94.2%, piperacillin/tazobactam 90.9%, trimethoprim/sulfamethoxazole 90.9%, temocillin 93.3%, and tobramycin 97.5%. The overall EA across all antimicrobials tested reached 96.0%. The research-use-only MBT FAST assay provides reliable AST within 6 h, substantially reducing turnaround time. Building on technology widely implemented in diagnostic laboratories, this approach holds promise for integration into microbiology practice.

β-Lactams are the most widely prescribed antibiotic class globally, comprising penicillins, cephalosporins, carbapenems, and monobactams. Their continual release to the environment raises concerns about both direct ecotoxicity and potential indirect effects on ecosystem function. This review highlights three key findings; 1) environmental concentrations can exceed predicted no-effect concentrations for resistance selection; for example ceftriaxone had been reported 6160 µg/L in wastewater influent and 4150 µg/L in effluent in India, indicating that many β-lactams have removal efficiency below 33%, 2) ecotoxicity data show that cyanobacteria (e.g. Microcystis aeruginosa, EC50 0.0037 mg/L for amoxicillin) are ≥ 1,000-fold more sensitive than macrofauna, and that chronic exposure at ng-µg/L levels may promote selection of antimicrobial resistance and facilitate horizontal gene transfer of these genes and 3). β-lactam resistance genes (blaCTX-M, blaNDM, blaOXA) are ubiquitous in wastewater and manure-amended soils and can persist even after the degradation of the parent compounds. Collectively, these finding indicates that β-lactam antibiotics pose significant risks to aquatic and soil ecosystems by contributing to the proliferation and maintenance of antimicrobial resistance in environmental reservoirs. The widespread environmental occurrence and persistence of β-lactams, along with associated resistance determinants, represent emerging One Health concerns. This narrative review synthesizes current literature on the ecotoxicological effects of β-lactam antibiotics, focusing on their major environmental sources, distribution across environmental matrices, impacts on non-target organisms, and emerging strategies to mitigate their environmental burdens. We further emphasize cross-disciplinary solutions spanning engineering, microbial ecology, policy, identify critical research gaps, and propose pragmatic pathways to reduce environmental selection pressure from β-lactams.