Search Results (179)

Antimicrobial resistance (AMR) is a growing global health threat, with wild birds increasingly recognized as potential reservoirs of resistant pathogens and as sentinels of environmental AMR. This study investigated the occurrence and AMR profiles of Gram-negative bacteria isolated from wild birds that died at the Wildlife Rescue Center in Vanzago, Lombardy, in 2024. Cloacal swabs were collected from 112 birds representing various ecological categories. A total of 157 Gram-negative bacteria were isolated and identified, including clinically relevant genera and species, such as Escherichia coli, Klebsiella pneumoniae, Enterobacter spp., Salmonella spp., Pseudomonas aeruginosa, and Acinetobacter baumannii. Antimicrobial susceptibility testing revealed resistance to first-line and critically important antimicrobials, including those exclusively authorized for human use. Notably, a phenotype compatible with Extended-Spectrum Beta-Lactamase (ESBL) production was detected in four out of ten (40%) K. pneumoniae isolates. In addition, 20 out of the 157 (12.7%) isolated bacteria phenotypically exhibited a resistance profile indicative of AmpC beta-lactamase (AmpC) production, including Enterobacter spp. and P. aeruginosa. Resistance patterns were particularly interesting in birds with carnivorous, scavenging, or migratory-associated behaviors. These findings highlight the role of wild birds in the ecology and dissemination of antimicrobial-resistant bacteria (ARB) and highlight the need for wildlife-based AMR monitoring programs as part of a One Health approach. Full article

Klebsiella pneumoniae carbapenemases (KPCs) are a group of class A β-lactamases of Gram-negative bacteria leading to difficult-to-treat infections. We evaluated the global epidemiology of KPC-producing Gram-negative clinical isolates. A systematic search of six databases (Cochrane Library, Embase, Google Scholar, PubMed, Scopus, and Web of Science) was conducted. Extracted data were tabulated and evaluated. After screening 1993 articles, 119 were included in the study. The included studies originated from Asia (n = 49), Europe (n = 29), North America (n = 14), South America (n = 11), and Africa (n = 3); 13 studies were multicontinental. The most commonly reported KPC-producing species were Klebsiella pneumoniae (96 studies) and Escherichia coli (52 studies), followed by Enterobacter cloacae (31), Citrobacter spp. (24), Klebsiella oxytoca (23), Serratia spp. (15), Enterobacter spp. (15), Acinetobacter baumannii complex (13), Providencia spp. (11), Morganella spp. (11), Klebsiella aerogenes (9), Pseudomonas aeruginosa (8), Raoultella spp. (8), Proteus spp. (8), and Enterobacter aerogenes (6). Among the studies with specific bla_KPC gene detection, 52/57 (91%) reported the isolation of bla_KPC-2 and 26/57 (46%) reported bla_KPC-3. The antimicrobial resistance of the studied KPC-producing isolates was the lowest for ceftazidime–avibactam (0–4%). Resistance to polymyxins, tigecycline, and trimethoprim–sulfamethoxazole in the evaluated studies was 4–80%, 0–73%, and 5.6–100%, respectively. Conclusions: The findings presented in this work indicate that KPC-producing Gram-negative bacteria have spread globally across all continents. Implementing proper infection control measures, antimicrobial stewardship programs, and enhanced surveillance is crucial. Full article

Colistin has re-emerged as a last-resort antibiotic for treating infections caused by multidrug-resistant (MDR) Gram-negative bacilli (GNB). However, increasing resistance threatens its efficacy. This study aimed to evaluate colistin resistance trends among clinical isolates of Gram-negative bacilli isolated over a five-year period at a large Emergency Hospital in North-Eastern Romania. A total of 23,143 GNB strains were isolated during the study period, including 14,531 Enterobacterales and 8294 non-fermenting Gram-negative bacilli. The percentage of colistin-resistant strains among those analyzed was 3.98%. Species-specific analysis focused on Klebsiella spp., Escherichia coli, Enterobacter spp., Citrobacter spp., Pseudomonas spp., and Acinetobacter spp. Klebsiella spp. exhibited the highest prevalence of colistin resistance, accounting for over 80% of all colistin-resistant strains, with annual resistance rates fluctuating between 12.97% and 21.64%. Colistin resistance among E. coli was low (0.18–1.25%). Citrobacter spp. showed no resistance in the last three years of the study, and Enterobacter spp. maintained relatively stable resistance (3–5%). Resistance in Pseudomonas spp. remained below 1%, while Acinetobacter spp. showed a resistance rate of 5.43%. Several distinct resistance phenotypes were identified among Klebsiella spp., Pseudomonas spp., and Acinetobacter spp. strains, reflecting both endemic and sporadic circulation patterns. The study highlights a persistent presence of colistin resistance, especially in Klebsiella spp., underlining the importance of ongoing surveillance. Despite low resistance in other species, the emergence of resistant strains underscores the need for robust antimicrobial stewardship and infection control policies. Full article

Background: Reusable tourniquets are commonly used to aid venipuncture and blood collection. However, inadequate disinfection may lead to bacterial contamination and increase the risk of healthcare-associated infections (HAIs). Tourniquets can function as fomites, facilitating the spread of pathogenic bacteria. This study assessed microbial contamination of reusable tourniquets in the emergency department and operating theatre, focusing on clinically relevant HAI-associated pathogens. Methods: Tourniquets from four hospital departments (emergency: adult observation and resuscitation; surgical theatres: pediatric and adult general surgery) were sampled at three time points (n = 12). DNA was extracted and analyzed via 16S rRNA sequencing using NGS technology to identify microbial contamination and taxonomic composition. Results: Sequencing revealed 131 bacterial species across the 12 tourniquets, including clinically important pathogens. Among the top ten HAI-associated groups, Klebsiella spp. were detected in 5/12 samples, Enterococcus spp. in 9/12, Staphylococcus aureus in 1/12, Pseudomonas aeruginosa in 9/12, and Acinetobacter spp. in 10/12. No Escherichia coli, Clostridium difficile, coagulase-negative staphylococci, Proteus spp., or Enterobacter spp. were found. Emergency department tourniquets showed higher bacterial loads; operating theatres had greater species diversity. Conclusions: Reusable tourniquets harbor significant bacterial contamination. Considering disinfection challenges and the lack of guidelines, single-use tourniquets should be considered to reduce HAI risk. Full article

Background: The qacE gene and its variant, qacE∆1, have been associated with resistance to antimicrobials and biocides. This poses a threat to infection prevention, control and treatment. Several studies investigated this relationship with conflicting results. The aim of this research was to determine the prevalence of qacE and qacE∆1 in clinical extended spectrum β-lactamase- (ESBL) and carbapenemase-producing Klebsiella spp. and Enterobacter spp. and elucidate the association of these genes with resistance to sodium hypochlorite. Methods: This study included 216 isolates of ESBL- and carbapenemase-producing multidrug-resistant (MDR) Klebsiella spp. and Enterobacter spp. These isolates were identified by VITEK-2 analyser. The MIC and MBC of sodium hypochlorite were determined using the microbroth serial-dilution method. PCR was used to detect gene variants. A regression analysis investigated any association between qacE genotypes, MIC and MBC, as well as antimicrobial drug resistance profiles. Results: Overall, there was a high prevalence of qacE and qacE∆1 variants (84.7%; 95% CI, 79.2–89.2). There was a high prevalence of qacE∆1 (80.6%; 95% CI, 74.6–85.6) as compared to qacE (15.3%, 95% CI, 10.8–20.8). The MIC₅₀ and MIC₉₀ of the isolates ranged between 7031 mg/L and 9375 mg/L and 14,060 mg/L and 18,750 mg/L, respectively, while the MBC ranged from 48,750 mg/L to 18,750 mg/L. There was no association between qacE genotypes and high MIC and MBC as well as antimicrobial drug resistance. Conclusions: The MIC and MBC of sodium hypochlorite are higher than what is currently used for disinfection in Botswana. There is a high prevalence of qacE and qacE∆1; however, these genes do not seem to be associated with resistance to sodium hypochlorite. Full article

Background/Objectives: The overuse of antibiotics has led to the emergence of antibiotic-resistant bacteria, posing a global public health challenge. Among these, extended-spectrum β-lactamase and carbapenemase-producing Enterobacteriaceae (ESBL-E and CPE) are of particular concern due to their potential to spread resistance in various environments. Understanding the prevalence and spread of these bacteria in the influent and effluent of wastewater treatment plants is essential. Methods: This study examined ESBL-E and CPE in wastewater from three WWTPs in Ouagadougou, Burkina Faso, and was conducted between February and August 2024. Phenotypic detection of ESBL-E was performed on the isolates using the double-disk synergy test and the combination disk test, whereas the CPE detection employed the combination disk test and the modified Hodge test. Results: A total of 250 Enterobacteriaceae isolates were found, with Escherichia coli, Klebsiella spp., Enterobacter spp., and Buttiauxella spp. the most predominant taxa. Phenotypic analysis revealed a high prevalence of ESBL-E, particularly in influent samples, with rates ranging from 55 to 98% across the WWTPs. CPE detection showed varying prevalence, with higher proportions identified in effluent samples, ranging from 37 to 68%, depending on the plant. These findings highlight the critical role of WWTPs in the persistence and potential spread of antibiotic-resistant bacteria. Conclusions: This study underscores the urgent need for improved wastewater treatment technologies and comprehensive monitoring systems to reduce the dissemination of ESBL-E and CPE in the environment. Addressing these challenges is crucial for mitigating the public health risks associated with antimicrobial resistance. Full article

This study examines temporal patterns in pathogens isolated from prosthetic joint infection (PJI) cases and antimicrobial resistance patterns at a Romanian orthopedic center. We have conducted a retrospective cohort study that included 674 patients undergoing hip or knee replacement revision surgery between January 2016 and December 2023. From these, 102 confirmed PJI cases requiring surgical intervention were selected for analysis. We isolated 27 microorganisms from acute PJI cultures and 82 from chronic PJIs. Staphylococcus epidermidis (33 cases, 30.3%; 95% CI 22.0–40.3) was the predominant pathogen, with coagulase-negative Staphylococci (22 cases, 20.18%; 95% CI 0.9–41.3) and Enterobacteriaceae (13 cases, 11.9%; 95% CI 6.4–18.3) also prevalent. Methicillin resistance was identified in 43.6% of coagulase-negative staphylococci and 45.5% of Staphylococcus aureus isolates. All Gram-positive isolates remained susceptible to vancomycin, linezolid, and tigecycline. Among Gram-negative bacilli, Klebsiella oxytoca and Proteus mirabilis showed resistance to third-generation cephalosporins, with phenotypic profiles suggestive of extended-spectrum β-lactamase (ESBL) production. All Escherichia coli, Enterobacter spp., and Citrobacter freundii strains were fully susceptible to tested agents, while Pseudomonas aeruginosa exhibited reduced susceptibility to ciprofloxacin, aztreonam, and imipenem. Among the isolated strains, 47 were multidrug-resistant (MDR), with Staphylococcus aureus accounting for the highest MDR count, including methicillin resistance. The distribution of microorganism types and MDR strains remained consistent throughout the study period, with no significant association between infection type and MDR strain presence or between infection site and microorganism presence except for a strong association between MDR strains and the type of microorganism (p < 0.05). The microbial profile and resistance patterns in PJIs have remained stable over eight years. Our observations do not suggest that MDR PJIs are more commonly acute cases, contrary to what has been highlighted in previous reports. The ongoing prevalence of MDR strains underscores the importance of targeted antimicrobial treatments based on local susceptibility profiles. Full article

Background: Infections of the biliary tract are found frequently in pathologically or surgically altered bile ducts. Mostly these infections result from the ascent of bacteria or fungi from the small bowel, although hematogeneous infections of the biliary system may also occur. The biliary sphincter and the continuous flow of bile are thought to prevent or limit ascending infections. Obstructive alterations in the biliary system are the most frequent indication of endoscopic retrograde cholangiography (ERC). The aim of this study was to analyze the spectrum and frequency of microbes within the bile, and discover the influence of earlier sphincterotomy. Methods: In our department, we routinely aspirate bile for microbiologic culture during ERC. For this study, all ERC performed in 2014–2018 were retrospectively analyzed, including all microbiological reports. Indications for the endoscopic examination were also recorded. In addition, the findings were correlated with whether or not a sphincterotomy had been previously performed, and whether or not there had been antibiotic treatment prior to the examination. Results: A total of 2253 successful standard ERC procedures were performed between 2014 and 2016. In 486 cases, bile was aspirated and sent for microbiologic culture. In total, 1220 bile samples were analyzed, and bacteria or fungi were found in 1029 (86.0%). Enterococci and Enterobacter were found most commonly, but E. coli, streptococci, klebsiella, and staphylococci were also found. In 11.2% of positive cultures, multiresistant pathogens were identified. In up to 29% Candida spp., most commonly, Candida albicans (68%) were also found, either alone or in conjunction with bacteria. Neither prior sphincterotomy nor the use of peri-interventional antibiotics had a major influence on the frequency with which positive bile cultures were detected. Conclusions: Aspiration of bile during ERC is of high clinical relevance, because microbiological analysis reveals the frequent presence of bacteria and fungi, knowledge of which may be useful for deciding on anti-infective treatment. Full article

Background and Clinical Significance: Acute pediatric rhinosinusitis is most commonly caused by Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. The involvement of Enterobacter species is rare and typically linked to chronic or nosocomial infections. Typical cases of acute rhinosinusitis in children present with abundant nasal discharge, headache, and fever and are generally managed with systemic antibiotics, nonsteroidal anti-inflammatory drugs (NSAIDs), mucolytics, and topical intranasal treatment. Atypical presentations prompt heightened clinical attention, and depending on the symptoms and patient status, surgical interventions might be considered. Case Presentation: We report the case of a previously healthy 5-year-old boy presenting with painful unilateral palpebral edema, minimal ipsilateral nasal discharge, and persistent headache despite standard rhinosinusitis therapy. Imaging tests revealed complete right maxillary sinus opacification. As the clinical response to ceftriaxone and dexamethasone was minimal, we opted for endoscopic sinus surgery. A nasal swab culture identified Enterobacter spp. in the nasal discharge. Conclusions: Unusual pathogens like Enterobacter spp. can cause acute sinusitis in children without prior risk factors. Early surgical intervention and culture-adjusted antimicrobial therapy remain critical for favorable outcomes. Full article

Edible flowers have been used since ancient times directly as food, flavoring agents, and garnish in food products, and are now reappearing in modern cuisine. Edible flowers have gained popularity due to changing consumer habits focused on healthier food options. In addition to contributing to the esthetics and flavor of various dishes, edible flowers are now recognized for their nutritional value, as they contain bioactive components with different health benefits. However, a significant concern regarding edible flowers is the potential contamination by undesirable microorganisms. Since edible flowers are often consumed fresh or minimally processed, they can pose a microbiological risk. Edible flowers may be susceptible to contamination by various pathogenic microorganisms, particularly Bacillus spp., Enterobacter spp., Salmonella spp., and Staphylococcus aureus. In addition, mycotoxin-producing fungi, such as Aspergillus, Penicillium, Alternaria, or Fusarium, can be found in various flowers. Good agricultural practices, hygienic handling, and appropriate storage are essential to reduce contamination and guarantee the safe consumption of edible flowers. Since current investigations on the microbiological safety aspects of edible flowers are scarce, this review aims to provide an overview of the consumption of edible flowers and a discussion of their uses, health benefits, and risks, focusing on microbiological aspects. Full article

Currently, multidrug-resistant (MDR) bacteria are a global problem, which requires modern approaches and effective pharmaceutical agents. Substances isolated from nature sources have a strong potential in combating highly virulent and antibiotic-resistant microorganisms, including within the ESKAPE group (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.). One of these substances is mangiferin, the bioactive compound obtained from parts of Mangiferin indica L. Mangiferin has a low aqueous solubility, which causes low activity and requires additional modification or delivery system to increase its concentration in the cell. Many studies show that it has multiple biological effects and can be used as an antioxidant or an anticancer agent, and it can exhibit antibacterial properties. Extracts obtained from plant parts show high efficacy in low doses against the ESKAPE group and other strains. This makes mangiferin a possible candidate as a strong agent against bacterial infections. The mechanisms underlying the action of mangiferin on bacterial cells are poorly understood. This review summarizes studies confirming the antibacterial properties of mangiferin both in its native form and using delivery systems. Full article

Undisturbed soils are essential ecosystems with high microbial diversity. Microorganisms present in the soil can regulate biogeochemical cycles, making available and transforming different minerals in the soil, such as nitrogen, phosphorus and sulfur. In this study, the microbiota of undisturbed soils was characterized using an integrated approach of 16S rRNA ribosomal gene amplicon analysis and classical microbiology techniques. Phylum-level analyses revealed a high abundance of Proteobacteria, Acidobacteria, Verrucomicrobia and Actinobacteria, key groups in nutrient recycling, organic matter decomposition and plant-microorganism interaction. In the genus analysis, Nitrospira spp., Candidatus Koribacter spp., Burkholderia spp., Bacillus spp., Flavobacterium spp. and Pedomicrobium spp. were identified, with important functions in nitrification, plant growth promotion, organic matter degradation, and recovery of degraded soils. On the other hand, by using selective and differential media, it was possible to demonstrate the presence of microorganisms such as Enterobacter spp. and Hafnia spp., with the ability to solubilize phosphorus and potassium and produce siderophores, which are likely contributing to the biogeochemical cycles and plant growth within the soil studied. Full article

Skin microbiota plays a crucial role in host defense. Disruptions in this balance can lead to systemic infections. Colonization by pathogenic microorganisms significantly increases the risk of symptomatic infections, prolongs hospital stays and increases healthcare costs. In Romania, the widespread misuse of antibiotics in the community further complicates the management of bacterial resistance, emphasizing the need for proactive measures. Our institution implemented a comprehensive multi-body-site colonization screening protocol starting from January 2024 until June 2024. The screening targeted high-risk patients, including those in ICUs, Oncology, and Hematology Clinics, and individuals with prior hospitalizations, antibiotic use, or medical devices. This study aimed to investigate the prevalence of colonization by multidrug-resistant organisms upon hospital admission and assess the changes in colonization rates during hospitalization. Samples from nasal, axillary, inguinal, and rectal swabs were processed on specialized chromogenic media to detect multidrug-resistant organisms such as methicillin-resistant S. aureus (MRSA), ESBL-producing Enterobacterales, and carbapenemase-producing bacteria. During the first two trimesters of the year 2024, 1522 patients aged 14 to 99 years underwent multi-body-site colonization screening at the County Clinical Emergency Hospital Sibiu, Romania. A total of 18,993 samples were analyzed, yielding a diverse range of bacterial isolates. The most common results were Escherichia coli-ESBL-negative (3584 cases, 18.9%) and the KESC bacteria group (Klebsiella spp., Enterobacter spp., Serratia spp., and Citrobacter spp.)-MDR-negative (3435 cases, 18.1%). Conversely, positive results were less frequent, with Acinetobacter baumannii-MDR-positive results in 62 cases (0.3%), E. coli-ESBL-positive results in 342 cases (1.8%), and KESC group-MDR-positive results in 491 cases (2.6%). Other notable findings included Enterococcus faecium-VRE-positive (157 cases, 0.8%) and MRSA-positive nasal swabs (141 cases, 0.7%). Rare isolates included Enterococcus faecalis-VRE-positive (4 cases, 0.0%) and Proteeae group-MDR-positive (33 cases, 0.2%). Negative screening for MRSA was prevalent across nasal (1850 cases, 9.7%), inguinal (742 cases, 3.9%), and axillary swabs (1124 cases, 5.9%), with substantially lower positive rates. The diversity of swab types and their distribution across various clinics and departments underscores the broad diagnostic approaches and patient-care strategies adopted during the study. These findings highlight the need for tailored infection prevention strategies and continuous surveillance to mitigate the spread of multidrug-resistant organisms and enhance patient safety across diverse clinical environments. Full article

Introduction: The increase in the rates of multidrug-resistant bacteria in healthcare environments has been recognized as a global public health problem. In view of the scarcity of data on the neonatal population, this study aimed to provide information on the genotypic and epidemiological characteristics of Gram-negative microorganisms isolated from colonization and infection sites in neonates admitted to a tertiary university center of high complexity. Methods: Enterobacterales and non-fermenting Gram-negative bacilli previously collected in a prospective cohort study were submitted to genotypic identification, detection of extended-spectrum β-lactamases (ESBL), carbapenemases and biofilm production, detection of specific virulence markers in Pseudomonas aeruginosa, and typing by pulsed-field gel electrophoresis. Results: The data found here revealed higher rates of infection by Klebsiella spp. and Serratia marcescens that caused bloodstream infection and pneumonia, respectively. In this study, high biofilm production was observed, with 95.0% of Enterobacterales and 100% of non-fermenting Gram-negative bacilli being producers. Most of the P. aeruginosa isolates carried pathogenicity factors such as alginate, hemolytic phospholipase C, exotoxin A, and rhamnolipids. The phenotypic analysis of ESBL revealed that 16 (5.3%) isolates produced these enzymes. Four of these isolates (66.7%) carried the CTX-M-9 gene, three (50%) carried the TEM gene, and one (16.7%) was positive for the SHV and CMY-2 genes. Univariate and multivariate Cox regression analyses were used to identify risk factors for colonization and infection by Gram-negative microorganisms. The results of multivariate analysis revealed that biofilm production by these microorganisms was associated with the persistence of colonization by the same pathogen in the newborn and increased by 75% the daily probability of the newborn developing infection. The production of ESBL also increased the daily probability of infection by 46.8 times. Conclusions: Enterobacterales showed average biofilm production, while the majority of non-fermenting Gram-negative bacilli were strong producers. The present data increase our knowledge of the molecular epidemiology of important Enterobacterales species, with emphasis on ESBL-producing Enterobacter cloacae and Klebsiella pneumoniae with emerging epidemiological potential in the neonatal intensive care unit of a tertiary university hospital. Furthermore, the results highlight the need for the monitoring and implementation of control measures and for restricting the use of broad-spectrum antibiotics. Full article

Poultry meat is the most consumed meat worldwide due to its low fat content, sensory qualities, and affordability. However, its rapid spoilage, especially when minced for products like hamburgers, is a challenge. Strategies such as sulfite addition or modified-atmosphere packaging (MAP) can help control spoilage and microbial growth. This study evaluated both approaches by analyzing bacterial development in poultry hamburgers through total viable counts and MALDI-TOF identification, combining food-pathogens detection. The addition of 5 mg/kg sulfites had a limited effect, whereas increasing CO₂ levels in the packaging significantly extended the shelf life by reducing the bacterial growth rates and prolonging the lag phases. The most affected bacteria were aerobic mesophilic and psychrotrophic bacteria, as well as Brochothrix thermosphacta. Carnobacterium spp. dominated the aerobic mesophilic group, while Enterobacter spp. was prevalent in Enterobacteriaceae and aerobic mesophilic isolates, highlighting its role in spoilage. Hafnia alvei was also relevant in the final spoilage stages. These results suggest the importance of these bacteria in poultry hamburger decay and demonstrate that MAP is an effective method to delay spoilage. Full article