Search Results (491)

Klebsiella pneumoniae (K. pneumoniae) is a major nosocomial pathogen with increasing antibiotic resistance. Treatment failures and high mortality rates in sepsis caused by K. pneumoniae are associated with difficulties in choosing an adequate antibacterial therapy in the presence of resistance to all available antibiotics, based on the results of susceptibility tests. This study aimed to identify “weak points” in the metabolism of K. pneumoniae, to be able to use these features in the future. Ten nosocomial K. pneumoniae strains were incubated with fourteen broad-spectrum antibiotics representing major drug classes. Aromatic metabolites were analyzed using gas chromatography–mass spectrometry after 24 h exposure. Phenyllactic acid (PhLA), comprising 86% of detected phenylcarboxylic acids, served as the metabolic activity marker. Antibiotics demonstrated multidirectional effects on aromatic compound metabolism. Doxycycline, nitrofurantoin, rifampicin, and tigecycline significantly suppressed metabolic activity, confirmed by decreased PhLA levels. Conversely, meropenem, cephalosporins (ceftriaxone, cefepime, cefotaxime, and ceftazidime), ciprofloxacin, and amikacin stimulated PhLA production, suggesting that bacterial metabolic activity was maintained despite the presence of antibiotics. PhLA is a promising biomarker for quantifying K. pneumoniae’s metabolic response to antibiotics. This potentially introduces a novel approach for future investigations into resistance mechanisms and has the potential to increase the effectiveness of therapies for multidrug-resistant K. pneumoniae infections by providing an additional analytical tool to traditional susceptibility testing methodologies. Full article

Background/Objectives: Multidrug-resistant (MDR) Escherichia coli is a critical One Health challenge, with rising resistance in both humans and animals. The present study aimed to compare antimicrobial resistance (AMR) profiles of E. coli isolates from hospitalized patients and food-producing animals in Satu Mare, a county located in northwestern Romania. Methods: Between 2022–2023, 701 samples were collected, leading to 571 non-duplicate E. coli isolates (420 human, 151 animal). Human strains were recovered from 21 hospital departments and originated from feces, urine, blood, sputum, ear secretions, cerebrospinal fluid, purulent wound secretions, and puncture fluids. Animal isolates were obtained from ceca collected at local slaughterhouses serving farms in north-west Romania, including samples from turkeys, broilers, and pigs. Antimicrobial susceptibility testing was performed against eight antimicrobials (amikacin, ampicillin, cefotaxime, ceftazidime, cefepime, ciprofloxacin, gentamicin, sulfamethoxazole/trimethoprim) using standardized methods. Resistance classification followed international definitions of MDR. Statistical associations between host species and resistance were assessed with chi-square tests. Results: Resistance levels were consistently higher in E. coli strains isolated from animals compared with those from humans (p < 0.05). Among human isolates, resistance to ampicillin (41.9%), ciprofloxacin (41.4%), and sulfamethoxazole/trimethoprim (45.7%) approached, but did not exceed 50%. In contrast, E. coli strains recovered from animals showed markedly higher resistance, exceeding 50% for ampicillin (78.8%), ciprofloxacin (65.6%), and cefotaxime (55.0%). Amikacin retained full activity against all animal isolates, whereas 2.8% of human strains were resistant. Overall, multidrug resistance (MDR) was observed in 70.0% of E. coli isolates from humans and 79.7% from animals, with the highest resistance burden in pig-derived isolates. Conclusions: The study underscores the veterinary sector as a key contributor to the maintenance and spread of MDR E. coli. Even in clinically healthy animals, resistance levels exceeded those observed in human isolates. These findings emphasize the need for coordinated One Health monitoring and stricter antimicrobial use policies in livestock to reduce transmission risks across human and animal populations. Full article

Background and Objectives: Acute acalculous cholecystitis (AAC) is rare, mostly in older males, with cardiovascular diseases, diabetes, critical illness, or systemic infection. Antibiotherapy before or after cholecystectomy is important for preventing septic shock and postoperative infections. Increasing antibiotic resistance was recently noted and can complicate antibiotherapy. Materials and Methods: A retrospective study of all patients who underwent cholecystectomy between 2018 and 2024 in the Clinical Emergency Hospital of Craiova was performed. The etiology of AAC, complications, hospitalization duration, mortality, positive bile cultures, and in vitro antibiotic resistance were analyzed. Results: A total of 802 calculous and 54 AAC were recorded. Patients with AAC were predominantly males (OR = 1.767, p = 0.043) with diabetes (OR = 2.049, p = 0.014) and were older (66.6 ± 13.2 vs. 61.4 ± 15.6, p = 0.014). Mortality was significantly higher in AAC (18.5 vs. 3.6%, OR = 6.058, p < 0.001), with longer hospitalization (mean 9.7 vs. 8.4 days) and more perforation. Positive bile cultures were recorded in 60.5–66.2% of cases, with a similar etiology in both forms of acute cholecystitis (mostly Gram-negative species, Enterococcus, and Staphylococcus); 10 ESBL Escherichia coli and Klebsiella strains, 11 Staphylococcus aureus MRSA, and 1 Enterococcus VRE strain were recorded. Antibiotic susceptibility in vitro was similar in both AAC and calculous cholecystitis. Significant resistance to cephalosporins and quinolones was recorded; the lowest resistance was noted for amikacin, carbapenems, chloramphenicol, colistin (Gram-negative bacteria), and vancomycin. Conclusions: AAC was encountered in older males with diabetes, with a higher rate of complications and in-hospital mortality. Bile cultures were positive in 60.5–66.2%, predominantly with Gram-negative, Enterococcus, and Staphylococcus species. Significant in vitro resistance to cephalosporins and quinolones was found. Full article

Background: Antibiotic resistance is a significant health problem in healthcare settings, especially intensive care units (ICUs), where patients are critically ill. This study aims to identify the bacterial profile and antibiotic resistance patterns of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter, and Escherichia coli (ESKAPEE) in blood specimens collected from adult patients admitted to the ICUs of public hospitals in Abu Dhabi, United Arab Emirates. The World Health Organization lists these pathogens as priority pathogens that greatly threaten humans. Methods: This cross-sectional study used routinely collected data through the AMR surveillance system between 2018 and 2022. Results: A total of 838 culture-positive blood specimens were reported during the study period, and 965 ESKAPEE pathogens were isolated. The most frequently isolated bacteria were Klebsiella pneumoniae (31%), Escherichia coli (22%), and Staphylococcus aureus (20%). Acinetobacter baumannii exhibited high resistance to Amikacin (81%), Meropenem (72%), and Imipenem (87%). Escherichia coli demonstrated resistance to Imipenem (42%) and Cefotaxime (54%). Klebsiella pneumoniae showed resistance to Imipenem (37%) and Cefotaxime (39%). Staphylococcus aureus showed resistance to Penicillin G (80%), Oxacillin (4%), and Ciprofloxacin (54%). Conclusions: The study showed a high prevalence of resistance in the most frequently isolated ESKAPEE pathogens in adult ICU patients. This brings into focus the need for appropriate infection control measures and strong antibiotic stewardship programs. The findings of the study support the ongoing efforts to deploy a better diagnostic tool for rapid pathogen identification, which is key in the targeted management of patients with bloodstream infection, especially in ICUs. Full article

This study aimed to investigate the epidemiological characteristics and antimicrobial resistance patterns of Bacillus cereus (B. cereus) in bovine mastitis within Inner Mongolian dairy herds, with a focus on virulence gene distribution and their clinical implications. A cross-sectional epidemiological investigation was conducted across three large-scale dairy farms. A total of 340 bacterial strains were isolated from milk samples collected from 108 cows with clinical mastitis, all of which underwent comprehensive PCR testing. Antimicrobial susceptibility testing was performed using the Kirby–Bauer disk diffusion method against eight antibiotics. Virulence gene profiling was conducted for all B. cereus isolates, and murine challenge experiments were performed to assess virulence-factor-dependent pathogenicity. Bacteriological analysis identified B. cereus as the predominant pathogen (104 strains, 30.58%), followed by Staphylococcus spp. (74 strains, 21.76%). Antimicrobial susceptibility testing revealed high resistance to tetracycline (38.46%), cotrimoxazole (15.38%), and ciprofloxacin (7.69%), while complete sensitivity (100%) was observed for gentamicin, amikacin, and roxithromycin. Virulence gene profiling demonstrated universal presence of nheA, nheB, and entFM genes in all isolates, with bh1D detected in only 21.15% (22/104) of strains. Murine challenge experiments confirmed virulence-factor-dependent pathogenicity, with strains harboring nine virulence factors inducing significant upregulation of hepatic inflammatory markers (p < 0.05) and histopathological alterations in hepatic and renal tissues compared to strains with three virulence factors. Our findings highlight B. cereus as an emerging virulent pathogen in Inner Mongolian dairy herds, necessitating enhanced surveillance of virulence factors and antimicrobial stewardship in mastitis management. This study provides critical epidemiological data to inform clinical veterinary practices and targeted intervention strategies. Full article

Drug-resistant tuberculosis (DR-TB) threatens global TB control. We investigated the prevalence and molecular characteristics of second-line drug resistance among rifampicin (RIF)- and/or isoniazid (INH)-resistant Mycobacterium tuberculosis complex (MTBC) isolates in São Paulo, Brazil, using the MTBDRsl v. 2.0 line-probe assay. MTBC isolates RIF- and/or INH-resistant by GenoType MTBDRplus or phenotypic testing (2019–2021) were subsequently tested by MTBDRsl for fluoroquinolone (FQ) and injectable drugs (capreomycin, amikacin, kanamycin) resistance. Isolates with inferred mutations underwent Sanger sequencing. Of 13,557 isolates, 728 (5.4%) were RIF- and/or INH-resistant (297 INH-R, 235 RIF-R, 196 MDR). Among them, 623 (85.6%) were tested by MTBDRsl; 582 (93.4%) showed no additional resistance, while 41 (6.6%) carried mutations. FQ resistance was detected in 38 isolates (92.7%), mostly in gyrA (n = 35). Three isolates with gyrB mutations were wild-type by sequencing. Two MDR isolates harbored the rrs a1401g mutation, and one also harbored gyrA D94G. Sequencing confirmed resistance in 38 of 41 isolates. Most MDR strains with second-line mutations (n = 32/33; 97%) were pre-XDR. Affected patients were predominantly male (68.4%), with pulmonary TB (92.1%), and unfavorable outcomes (39.5%). Second-line resistance prevalence was low overall, but FQ resistance was high among MDR isolates. Findings support integrating molecular and sequencing-based tools for accurate detection and management of DR-TB. Full article

Ophthalmic lens coatings are increasingly designed to combine optical, mechanical, and biological functions. This systematic review, registered in PROSPERO and conducted according to PRISMA 2020 guidelines, synthesized 54 experimental, preclinical, and clinical studies on coatings for spectacle lenses, contact lenses, and intraocular lenses. Spectacle lens studies consistently showed that anti-reflective and blue-light filtering coatings reduce glare perception, improve contrast sensitivity, and provide UV protection, while laboratory tests demonstrated significant reductions in impact resistance, with fracture energy of CR-39 lenses decreasing by up to 63% when coated. Contact lens research revealed that plasma and polymeric coatings reduce water contact angles from >100° to <20°, enhancing wettability, while antimicrobial strategies such as melamine binding or nanoparticle-based films achieved >80% reductions in bacterial adhesion. Drug-eluting approaches sustained antibiotic or antioxidant release for periods ranging from 24 h to 6 days, with improved ocular bioavailability compared with drops. Intraocular lens studies demonstrated that heparin surface modifications reduced postoperative flare and anterior chamber cells, and phosphorylcholine or alkylphosphocholine coatings suppressed lens epithelial cell proliferation. Drug-loaded coatings with methotrexate, gefitinib, or amikacin significantly inhibited posterior capsule opacification and infection in ex vivo and animal models. Collectively, coatings improve visual comfort, photoprotection, wettability, and biocompatibility, but clinical translation requires solutions to mechanical trade-offs, long-term stability, and regulatory challenges. Full article

Klebsiella pneumoniae is one of the top pathogens causing bloodstream infections (BSIs) worldwide. The rise of carbapenem-resistant K. pneumoniae (CRKP) and multidrug-resistant (MDR) strains is of particular concern as therapeutic options are limited. Analyzing local resistance profiles is essential for the success of antibiotic stewardship strategies. This study aims to explore the resistance profiles of K. pneumoniae strains identified in BSI in a tertiary care hospital over 7 years. Automated systems were used to test antibiotic susceptibility. Results were interpreted according to EUCAST clinical breakpoints. The rate of multidrug resistance (MDR) was 57.6%. The percentage of ESBL producers was 54.5%, and the percentage of carbapenemase producers was 43.2%. Overall resistance rates to other antibiotics were 47.1% to ciprofloxacin, 31.4% to gentamicin, 25.7% to amikacin, 20.9% to colistin, 19.6% to Fosfomycin, and 44.5% to trimethoprim/sulfamethoxazole. The highest resistance to colistin was recorded in 2023 (28%). More than half of the strains in the study were MDR and ESBL producers. K. pneumoniae resistance to colistin has increased during the last 7 years. The rates of carbapenemase-producing bacteria (CPB) are on the rise. The most frequently co-harboring carbapenemases were NDM and OXA-48. Local antibiotic resistance rates are crucial in implementing an effective antibiotic stewardship strategy. Full article

Background: Salmonellosis is a foodborne illness typically associated with gastroenteritis following the ingestion of products contaminated with Salmonella enterica. Although the aquatic environment is not a natural reservoir for Salmonella spp., its occurrence has been reported in various aquacultured species worldwide, including species from the Amazon Basin in South America. The World Health Organization has classified the emergence of multidrug-resistant (MDR) Salmonella strains as a global priority, underscoring the importance of monitoring antimicrobial resistance to mitigate public health risks. This study aimed to detect Salmonella spp. serotypes of clinical relevance to humans (S. Typhi, S. Paratyphi, S. Typhimurium, and S. Enteritidis) in farmed tambaqui hybrids and to assess the antimicrobial susceptibility of the isolates. Methods: A total of 55 Salmonella spp. strains, previously isolated from tambaqui hybrids (Colossoma macropomum) produced in fish farms in Mato Grosso, Brazil, were evaluated. Identification and susceptibility profiling were performed using the VITEK^®2 Compact automated system (BioMérieux, Marcy l’Étoile, France), testing 14 commonly used antimicrobials, including amoxicillin–clavulanic acid, piperacillin–tazobactam, cephalexin, cefuroxime axetil, ceftriaxone, cefepime, meropenem, ertapenem, amikacin, gentamicin, ciprofloxacin, and sulfamethoxazole–trimethoprim. Results: All isolates were confirmed as Salmonella spp., with no detection of clinically important serotypes. Moreover, all 55 strains were susceptible to the 14 antimicrobials tested. Conclusions: These findings indicate a low risk of pathogenic or resistant Salmonella from farmed tambaqui hybrids under the evaluated conditions. Nevertheless, ongoing microbiological monitoring remains essential, particularly in light of regulatory standards that prohibit the presence of Salmonella spp. in fish products and the potential emergence of MDR strains. Full article

Slaughterhouses serve as critical surveillance hubs for identifying subclinical and economically important diseases in food-producing animals. Trueperella (Arcanobacterium) pyogenes, an opportunistic pathogen commonly found on the mucous membranes of livestock, is associated with mastitis, abortion, and suppurative infections such as abscesses. In this study, we investigated 30 pig carcasses fully condemned due to vertebral osteomyelitis (VO) at two slaughterhouses in Gwangju, Republic of Korea, between November 2023 and May 2024. From abscess lesions, 11 T. pyogenes strains were isolated and characterized morphologically, biochemically, and genetically. The hemolytic exotoxin pyolysin (plo gene), a major virulence factor, was detected in five isolates (45.46%). Phylogenetic analysis of partial 16S rDNA sequences confirmed close clustering with known T. pyogenes reference strains. All 11 isolates exhibited multidrug resistance, showing resistance to 8–14 antimicrobial agents per strain. Complete resistance (11/11, 100%) was observed against amikacin (AMI), nalidixic acid (NAL), chloramphenicol (CHL), florfenicol (FFN), and trimethoprim/sulfamethoxazole (SXT). High resistance rates were also detected for erythromycin (ERY) and clindamycin (CLI) (10/11, 90.9%), ceftazidime (TAZ), ceftriaxone (AXO), ciprofloxacin (CIP) (7/11, 63.6%), and tetracycline (TET) and streptomycin (STR) (5/11, 45.5%), while gentamicin (GEN) resistance was found in three isolates (27.3%). In contrast, none of the isolates showed resistance to ampicillin, cefoxitin, or cefotaxime. These findings underscore the epidemiological value of abattoir-based monitoring in detecting emerging pathogens and tracking antimicrobial resistance. The results provide important baseline data to inform disease control strategies, guide antimicrobial stewardship, and support One Health approaches, including the development of preventive measures such as vaccines. Full article

Background: The benefit of adjunctive aminoglycosides in the treatment of patients with febrile neutropenia (FN) is controversial. We investigated the incidence of acute kidney injury (AKI) in patients with FN or suspected infection according to empirical amikacin treatment. Methods: This two-centre, retrospective cohort study was conducted at the University Hospitals of Basel (amikacin group) and Bern (non-amikacin group), Switzerland, between 2016 and 2022. Adult patients requiring antibiotic treatment after autologous hematopoietic stem cell transplantation (HSCT) were included. All patients received empiric beta-lactam treatment combined with amikacin in the amikacin group (only University Hospital Basel). The primary endpoint was the incidence of AKI within seven days after the initiation of antibiotic treatment. Results: Overall, 250 patients were included. The majority was male (n = 163, 65.2%) and had a median age of 61 years (interquartile range (IQR) 55 to 67). The median baseline eGFR was similar in both groups (>90 mL/min/1.7 m²). There was no statistically significant difference in the incidence of AKI (4/125 vs. 5/125, p = 1.0). The maximum decline in eGFR from baseline within 7 days was significantly higher in the amikacin group (−4 mL/min/1.7 m² (IQR 8 to −12) vs. −2 mL/min/1.7 m² (IQR −7 to −1), p = 0.001). Two patients suffered from an infection with an extended spectrum beta-lactamase producing (ESBL) pathogen. Conclusions: Amikacin treatment did not significantly impact the incidence of AKI in patients undergoing autologous HSCT. The short-term administration of amikacin in patients with normal to high baseline eGFR is safe regarding renal function. However, in a low-resistance setting, the omission of empirical amikacin treatment should be considered. Full article

The emergence of multidrug-resistant uropathogens requires the development of novel therapeutic strategies. This pilot study assessed the in vitro synergy between nitrofurantoin and aminoglycosides (amikacin, gentamicin, and tobramycin) against three major uropathogens: Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecalis. Ninety clinical isolates were tested using the disk diffusion and double-disk synergy methods. Statistical analysis included Kruskal–Wallis and Mann–Whitney U tests, as well as logistic regression models to assess associations between inhibition zone diameters and synergy occurrence. While synergy was observed in all bacterial species, it was neither universally present nor species-specific. Significant associations were identified between nitrofurantoin inhibition zone size and synergy with amikacin and tobramycin in E. coli, and with amikacin in K. pneumoniae. In E. faecalis, synergy was more likely with larger aminoglycoside inhibition zones, particularly tobramycin. These findings underscore the potential of nitrofurantoin–aminoglycoside combinations in treatment of multidrug-resistant urinary tract infections, while emphasizing the need for further studies incorporating quantitative synergy assays and clinical validation. Full article

Background: The aims of this paper are to examine the impact of the COVID-19 pandemic on the non-rational use of antibiotics and potential alterations in the antibiotic resistance profiles of multi-drug resistant (MDR) isolates of Klebsiella pneumoniae (KPN), Pseudomonas aeruginosa (PAE), and Acinetobacter baumannii (ABA). Material and Methods: This study was conducted at the tertiary University Hospital “Dr Dragisa Misovic-Dedinje” (Belgrade, Serbia) and was divided into three periods: pre-pandemic (1.4.2019–31.3.2020, period I), COVID-19 pandemic (1.4.2020–31.3.2021, period II), and COVID-19 pandemic-second phase (1.4.2021–31.3.2022, period III). Cultures were taken from each patient with clinically suspected infection (symptoms, biochemical markers of infection). All departments of the hospital were included in this study. Based on the source, all microbiological specimens were divided into 1° blood, 2° respiratory tract (tracheal aspirate, bronchoalveolar lavage fluid, throat, sputum), 3° central-line catheter, 4° urine, 5° urinary catheter, 6° skin and soft tissue, and 6° other (peritoneal fluid, drainage sample, bioptate, bile, incisions, fistulas, and abscesses). After the isolation of bacterial strains from the samples, an antibiotic sensitivity test was performed for each individual isolate with the automated Vitek^® 2 COMPACT. Antibiotic consumption testing was performed by the WHO guideline equations (ATC/DDD). Results: A total of 2196 strains of KPN, PAE, and ABA from 41,144 hospitalized patients were isolated (23.6% of the number of total isolates). The number of ABA isolates statistically increased (p = 0.021), while the number of PAE isolates statistically decreased (p = 0.003) during the pandemic. An increase in the percentage of MDR strains was observed for KPN (p = 0.028) and PAE (p = 0.027). There has been an increase in the antibiotic resistance of KPN for piperacillin–tazobactam, the third and fourth generations of cephalosporins (ceftriaxone, ceftazidime, and cefepime), all carbapanems (imipenem, meropenem, and ertapenem), and levofloxacin; of PAE for imipenem; and of ABA for amikacin. Total antibiotic consumption increased (from 755 DBD to 1300 DBD, +72%), especially in the watch and reserve group of antibiotics. The highest increases were noted for vancomycin, levofloxacin, azithromycin, and meropenem. MV positively correlated with the increased occurrence of MDR KPN (r = 0.35, p = 0.009) and MDR PAE (r = 0.43, p = 0.009) but not for MDR ABA (r = 0.09, p = 0.614). There has been a statistically significant increase in the Candida sp. isolates, but the prevalence of Clostridium difficile infection remained unchanged. Conclusions: The COVID-19 pandemic has influenced the increase in total and MDR strains of KPN, ABA, and PAE and worsened their antibiotic resistance profiles. An increase in the consumption of both total and specific antibiotics was observed, mostly of fluoroquinolones and carbapenems. A positive correlation between the number of patients on MV and an increase in MDR KPN and MDR PAE strains was noted. It is necessary to adopt and demand the implementation of appropriate antimicrobial stewardship interventions to decrease the resistance of intrahospital pathogens to antibiotics. Full article

Background: This study aimed to compare mortality rates and treatment efficacy between ceftazidime–avibactam (CAZ/AVI) and meropenem-based combination regimens in critically ill patients with carbapenem-resistant Gram-negative bacteria (CRGNB) infections. Methods: This retrospective study included 135 intensive care unit (ICU) patients diagnosed with CRGNB infections between 2020 and 2024. Patients were categorized on the basis of treatment: CAZ/AVI or alternative combinations that included meropenem with either amikacin or polymyxin. The primary outcomes were 14-day, 30-day, and 90-day all-cause mortality rates. The secondary outcomes included the clinical response on day 14 and the total duration of ICU hospitalization. Results: Among the patients, 74 received CAZ/AVI, whereas 61 were treated with meropenem-based regimens. No significant differences were observed in the baseline characteristics between the groups. There were no statistically significant differences in 14-day (27.0% vs. 31.1%), 30-day (41.9% vs. 47.5%), or 90-day mortality rates (62.2% vs. 65.6%) between the two groups (p = 0.738, 0.511, and 0.818, respectively), including within the pneumonia and bloodstream infection subgroups. Clinical success was observed in 64.9% of the CAZ/AVI group and 65.6% of the other group (p = 0.931), with comparable ICU lengths of stay (44.0 ± 29.1 vs. 41.5 ± 26.4 days, p = 0.974). Multivariate analysis revealed that advanced age, higher Sequential Organ Failure Assessment (SOFA) scores, elevated procalcitonin levels, and prolonged time from culture collection to the initiation of appropriate antibiotic therapy were independent predictors of increased 30-day mortality. Conclusions: CAZ/AVI demonstrated efficacy and mortality outcomes comparable to those of meropenem-based regimens in ICU patients with CRGNB infections. Prompt initiation of appropriate antimicrobial therapy remains critical. Full article

Background: Urinary tract infections (UTIs) are among the most common bacterial infections in children, with Escherichia coli as the leading pathogen. The rise in antimicrobial resistance, particularly extended-spectrum β-lactamase (ESBL) production, complicates empirical therapy, especially in countries with limited surveillance like Romania. Methods: We conducted a retrospective study on 248 pediatric patients aged 0–17 years diagnosed with E. coli UTI and admitted to a children hospital from Bucharest, Romania, between 2022 and 2024. Data collected included clinical presentation, laboratory values, and antimicrobial susceptibility testing. Patients were divided into ESBL and non-ESBL groups, and statistical comparisons were performed using SPSS v25. Results: Infants accounted for 68.1% of cases, with male sex predominating in this group (85.3%). ESBL-producing strains were identified in 19% of patients, more frequently in males (25% vs. 13.6%, p = 0.024). While inflammatory markers (CRP, leukocytes, neutrophils) were higher in complicated infections, they were paradoxically lower in ESBL cases. Non-ESBL isolates were highly susceptible to fosfomycin, third-generation cephalosporins, nitrofurantoin, and gentamicin. ESBL isolates showed resistance to most β-lactams but retained high susceptibility to fosfomycin (100%), carbapenems (>89%), cefoxitin (89.4%), and amikacin (85.1%). Conclusions: Our findings support the use of fosfomycin, nitrofurantoin, and selected aminoglycosides as viable empirical options in pediatric UTIs. Given the substantial ESBL prevalence and resistance to commonly used oral agents, local antibiogram data should guide empirical treatment strategies to preserve antibiotic efficacy and combat resistance. Full article