Arcobacteraceae: An Exploration of Antibiotic Resistance Featuring the Latest Research Updates.

The Arcobacteraceae bacterial family includes species isolated from animals and related food products. Moreover, these species have been found in other ecological niches, including water. Some species, particularly Arcobacter butzleri and Arcobacter cryaerophilus, have been isolated from human clinical cases and linked to gastrointestinal symptoms. The presence of antibiotic-resistant strains is a concern for public health, considering the possible zoonoses and foodborne infections caused by contaminated food containing bacteria resistant to antibiotic treatments. This review aims to highlight the importance of antibiotic resistance in Arcobacter spp. isolates from several sources, including information about antibiotic classes to which this bacterium has shown resistance. Arcobacter spp. demonstrated a wide spectrum of antibiotic resistance, including several antibiotic resistance genes. Antibiotic resistance genomic traits include efflux pumps and mutations in antibiotic target proteins. The literature shows a high proportion of Arcobacter spp. that are multidrug-resistant. However, studies in the literature have primarily focused on the evaluation of antibiotic resistance in A. butzleri and A. cryaerophilus, as these species are frequently isolated from various sources. These aspects underline the necessity of studies focused on several Arcobacter species that could potentially be isolated from several sources.

Phenotypic antibiotic susceptibility profile of clinical Enterobacteriaceae isolates from Kaduna State, northwest Nigeria.

Background. The increasing resistance of clinical Enterobacteriaceae isolates to commonly prescribed antibiotics has been reported around the world. Data are generally lacking on the prevalence and antibiotic susceptibility profile of clinical Enterobacteriaceae isolates from Kaduna, northwest Nigeria. This study thus aimed to determine the diversity and antibiotic resistance profile of clinical Enterobacteriaceae isolates recovered from clinical specimens from patients admitted to two selected healthcare institutions in Kaduna. Methods. This was a prospective cross-sectional study conducted between September and December 2021. Non-duplicate clinical bacterial isolates recovered from various specimens were collected and identified using rapid biochemical identification kits. The susceptibility of identified Enterobacteriaceae to various antibiotics and phenotypic detection of carbapenemase enzymes were thereafter determined. The data were analysed and visualized using R software version 4.3.1. Results. Of the 500 bacterial isolates recovered from specimens collected for the purpose of clinical bacteriology diagnostics, 108 (21.6 %) were identified as Enterobacteriaceae, with Pantoea agglomerans (52, 48.1 %) and Klebsiella oxytoca (19, 17.6 %) being the most prevalent. The isolates exhibited high resistance to azithromycin (69 %) and ceftazidime (42 %), while exhibiting low resistance to amikacin (7 %) and imipenem (10 %). Among the carbapenem-resistant Enterobacteriaceae (CRE) isolates, a significant proportion (12/17, 70.6 %) tested positive for carbapenemase activity. Conclusion. This study reports a high prevalence of multidrug-resistant Enterobacteriaceae in Kaduna, northwest Nigeria. The emergence of pathogenic P. agglomerans and an alarmingly high prevalence of carbapenemase-producing CRE were also observed. The presence of carbapenemase producers in an area with low carbapenem usage and resistance rates raises significant concerns. Continuous surveillance and robust antibiotic stewardship policies are imperative to preserve the efficacy of carbapenems in this region.

A novel pathogenic species of genus Stenotrophomonas: Stenotrophomonas pigmentata sp. nov.

Introduction: Stenotrophomonas is a prominent genus owing to its dual nature. Species of this genus have many applications in industry and agriculture as plant growth-promoting rhizobacteria and microbial biological control agents, whereas species such as Stenotrophomonas maltophilia are considered one of the leading gram-negative multi-drug-resistant bacterial pathogens because of their high contribution to the increase in crude mortality and significant clinical challenge. Pathogenic Stenotrophomonas species and most clinical isolates belong to the Stenotrophomonas maltophilia complex (SMc). However, a strain highly homologous to S. terrae was isolated from a patient with pulmonary tuberculosis (TB), which aroused our interest, as S. terrae belongs to a relatively distant clade from SMc and there have been no human association reports. Methods: The pathogenicity, immunological and biochemical characteristics of 610A2T were systematically evaluated. Results: 610A2T is a new species of genus Stenotrophomonas, which is named as Stenotrophomonas pigmentata sp. nov. for its obvious brown water-soluble pigment. 610A2T is pathogenic and caused significant weight loss, pulmonary congestion, and blood transmission in mice because it has multiple virulence factors, haemolysis, and strong biofilm formation abilities. In addition, the cytokine response induced by this strain was similar to that observed in patients with TB, and the strain was resistant to half of the anti-TB drugs. Conclusions: The pathogenicity of 610A2T may not be weaker than that of S. maltophilia. Its isolation extended the opportunistic pathogenic species to all 3 major clades of the genus Stenotrophomonas, indicating that the clinical importance of species of Stenotrophomonas other than S. maltophilia and potential risks to biological safety associated with the use of Stenotrophomonas require more attention.

Purulent lymphadenitis caused by ST59 community-associated Methicillin-resistant Staphylococcus aureus in an infant.

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (CA-MRSA), which has the potential to produce serious infections, was a common cause of skin and soft tissue infections, acute purulent lymphadenitis was rare. CASE REPORT: The patient was a female infant with lumps, tenderness, and fever on the right side of the neck and groin. Laboratory tests suggested a bacterial infection. The diagnosis of acute purulent lymphadenitis was made based on the clinical signs and the results of a supporting exam. After three days, MRSA developed in the secretions of suppurative lymph nodes. Her mother's nasopharyngeal swab sample results revealed MRSA. The genotypes of two bacterial strains that underwent molecular analysis were identical. RESULTS: 17 days after admission, the patient showed signs of clinical recovery. CONCLUSIONS: The incident brought to light the possible spread of CA-MRSA in the Chinese population. Even without a definite path of infection, CA-MRSA should be taken into consideration when the standard treatment for children with acute purulent lymphadenitis is ineffective. Early infancy MRSA acquisition may be mostly caused by maternal-infant horizontal transmission.

The impact of sink removal and other water-free interventions in intensive care units on water-borne healthcare-associated infections: a systematic review.

With increasing awareness of water sinks as potential sources of outbreaks and transmission of multi-drug resistant (MDR) bacteria in intensive care units (ICUs), there is growing interest in water-free patient care systems. This systematic review reviewed and synthesized available evidence on the effectiveness of sink removal with or without water-free activities in the ICU environment to reduce water-borne healthcare-associated infections. We searched five databases (PubMed, MEDLINE, Scopus, Web of Science and Embase) for studies published from 1st January 1980 to 2nd April 2024 that examined water-less or water-free activities in the ICU to reduce healthcare-associated infections and patient colonization. Of 2075 articles, seven quasi-experimental studies (total: 332 patient beds) met the study selection criteria. Six of these seven studies (85.7%) were based in adult ICUs; one (14%) was in a neonatal ICU. Five of seven sites (71.4%) implemented water-less interventions after an outbreak. Water-free alternatives used included water-less bath products (six of seven; 85.7%), bottled water for consumption (three of seven; 42.9%), oral care (three of seven; 42.9%) and dissolving of oral medication (four of seven; 57.1%), designated 'contaminated' sink outside of patient and medication preparation areas for disposal of wastewater (four of seven; 57.1%). Implicated pathogens studied included MDR Gram-negative bacteria (four of seven; 57.1%), MDR Pseudomonas aeruginosa only (two of seven; 28.6%), and pulmonary non-tuberculous mycobacterium (NTB) (one of seven; 14.3%). Five of seven (71.4%) studies reported outbreak cessation. Preliminary evidence, from a limited number of studies of which the majority were conducted in an outbreak setting, suggest that sink removal and other water-free interventions in the ICU helped terminate outbreaks involving taps and decrease hospital-onset respiratory isolation of pulmonary NTB.

A case-control study of the clinical and economic impact of infections caused by Carbapenemase-producing Enterobacterales (CPE).

PURPOSE: The aim was to analyse the clinical and economic impact of carbapenemase-producing Enterobacterales (CPE) infections. METHODS: Case-control study. Adult patients with CPE infections were considered cases, while those with non-CPE infections were controls. Matching criteria were age (± 5 years), sex, source of infection and microorganism (ratio 1:2). Primary outcome was 30-day mortality. Secondary outcomes were 90-day mortality, clinical failure, hospitalisation costs and resource consumption. RESULTS: 246 patients (82 cases and 164 controls) were included. Klebsiella pneumoniae OXA-48 was the most common microorganism causing CPE infections. CPE cases had more prior comorbidities (p = 0.007), septic shock (p = 0.003), and were more likely to receive inappropriate empirical and definitive antibiotic treatment (both p < 0.001). Multivariate analysis identified septic shock and inappropriate empirical treatment as independent predictors for 7-day and end-of-treatment clinical failure, whereas Charlson Index and septic shock were associated with 30- and 90-day mortality. CPE infection was independently associated with early clinical failure (OR 2.18, 95% CI, 1.03-4.59), but not with end-of-treatment clinical failure or 30- or 90-day mortality. In terms of resource consumption, hospitalisation costs for CPE were double those of the non-CPE group. CPE cases had longer hospital stay (p < 0.001), required more long-term care facilities (p < 0.001) and outpatient parenteral antibiotic therapy (p = 0.007). CONCLUSIONS: The CPE group was associated with worse clinical outcomes, but this was mainly due to a higher comorbidity burden, more severe illness, and more frequent inappropriate antibiotic treatment rather than resistance patterns as such. However, the CPE group consumed more healthcare resources and incurred higher costs.

De novo Designing of the Antimicrobial Peptide as a Curative Agent for Methicillin-Resistant Staphylococcus aureus through a Computational Approach.

BACKGROUND: The emergence of resistance to multiple drugs has posed a multitude of difficulties that demand immediate attention and solutions. Multiple drug resistance arises from the accumulation of numerous genes within a single cell, each conferring resistance to a specific drug, and from the heightened expression of genes responsible for multidrug efflux pumps. These pumps effectively expel a diverse array of drugs from the cell. OBJECTIVE: The multi-drug-resistant organisms, including methicillin-resistant Staphylococcus aureus, are the hub of numerous diseases, from minute ailments to fatal diseases, like catheter infections. Nowadays, a combination of many antibiotics is given together as a multimodality therapy to cure MRSA infections. However, researchers are exploring novel approaches to find better solutions. METHODS: De novo designing of the peptide sequences has been done through an in silico tool. The peptides were further screened using different computational methods. Following this, the selection was conducted utilizing physicochemical properties as criteria. Molecular docking of the selected peptide sequence was carried out. Based on the highest docking score, the model complex was chosen for validation purposes by conducting studies through molecular dynamics simulations. RESULTS: A total of fifty-two novel antimicrobial peptides were designed and evaluated based on various parameters, targeting MRSA-specific proteins PBP2a and PVL toxin. Among these designed peptides, the peptide sequence VILRMFYHWAVKTNGP emerged as the optimal candidate, satisfying all the necessary parameters to be an effective antimicrobial peptide. CONCLUSION: Molecular docking and MD simulation results showed that the designed peptide sequence could be the possible solution for MRSA treatment.

Antimicrobial susceptibility and resistome of Actinobacillus pleuropneumoniae in Taiwan: a next-generation sequencing analysis.

Actinobacillus pleuropneumoniae infection causes a high mortality rate in porcine animals. Antimicrobial resistance poses global threats to public health. The current study aimed to determine the antimicrobial susceptibilities and probe the resistome of A. pleuropneumoniae in Taiwan. Herein, 133 isolates were retrospectively collected; upon initial screening, 38 samples were subjected to next-generation sequencing (NGS). Over the period 2017-2022, the lowest frequencies of resistant isolates were found for ceftiofur, cephalexin, cephalothin, and enrofloxacin, while the highest frequencies of resistant isolates were found for oxytetracycline, streptomycin, doxycycline, ampicillin, amoxicillin, kanamycin, and florfenicol. Furthermore, most isolates (71.4%) showed multiple drug resistance. NGS-based resistome analysis revealed aminoglycoside- and tetracycline-related genes at the highest prevalence, followed by genes related to beta-lactam, sulfamethoxazole, florphenicol, and macrolide. A plasmid replicon (repUS47) and insertion sequences (IS10R and ISVAp11) were identified in resistant isolates. Notably, the multiple resistance roles of the insertion sequence IS10R were widely proposed in human medicine; however, this is the first time IS10R has been reported in veterinary medicine. Concordance analysis revealed a high consistency of phenotypic and genotypic susceptibility to florphenicol, tilmicosin, doxycycline, and oxytetracycline. The current study reports the antimicrobial characterization of A. pleuropneumoniae for the first time in Taiwan using NGS.

A novel variant in Salmonella genomic island 1 of multidrug-resistant Salmonella enterica serovar Kentucky ST198.

Salmonella enterica serovar Kentucky ST198 is a major health threat due to its resistance to ciprofloxacin and several other drugs, including third-generation cephalosporins. Many drug-resistant genes have been identified in the Salmonella genomic island 1 variant K (SGI1-K). In this study, we investigated the antimicrobial resistance (AMR) profile and genotypic relatedness of two isolates of ciprofloxacin-resistant (CIPR) S. Kentucky ST198 from poultry in Northeastern Thailand. We successfully assembled the complete genomes of both isolates, namely SSSE-01 and SSSE-03, using hybrid de novo assembly of both short- and long-read sequence data. The complete genomes revealed their highly similar genomic structures and a novel variant of SGI1-K underlying multidrug-resistant (MDR) patterns, including the presence of blaTEM-1b, which confers resistance to beta-lactams, including cephalosporins and lnu(F) which confers resistance to lincomycin and other lincosamides. In addition, the chromosomal mutations in the quinolone resistance-determining region (QRDR) were found at positions 83 (Ser83Phe) and 87 (Asp87Asn) of GyrA and at positions 57 (Thr57Ser) and 80 (Ser80Ile) of ParC suggesting high resistance to ciprofloxacin. We also compared SSSE-01 and SSSE-03 with publicly available complete genome data and revealed significant variations in SGI1-K genetic structures and variable relationships to antibiotic resistance. In comparison to the other isolates, SGI1-K of SSSE-01 and SSSE-03 had a relatively large deletion in the backbone, spanning from S011 (traG∆) to S027 (resG), and the inversion of the IS26-S044∆-yidY segment. Their MDR region was characterized by the inversion of a large segment, including the mer operon and the relocation of IntI1 and several resistance genes downstream of the IS26-S044∆-yidY segment. These structural changes were likely mediated by the recombination of IS26. The findings broaden our understanding of the possible evolution pathway of SGI1-K in fostering drug resistance, which may provide opportunities to control these MDR strains.IMPORTANCEThe emergence of ciprofloxacin-resistant (CIPR) Salmonella Kentucky ST198 globally has raised significant concerns. This study focuses on two poultry isolates from Thailand, revealing a distinct Salmonella genomic island 1 variant K (SGI1-K) genetic structure. Remarkably, multiple antibiotic resistance genes (ARGs) were identified within the SGI1-K as well as other locations in the chromosome, but not in plasmids. Comparing the SGI1-K genetic structures among global and even within-country isolates unveiled substantial variations. Intriguingly, certain isolates lacked ARGs within the SGI1-K, while others had ARGs relocated outside. The presence of chromosomal extended-spectrum ß-lactamase (ESBL) genes and lincosamide resistance, lnu(F), gene, could potentially inform the choices of the treatment of CIPRS. Kentucky ST198 infections in humans. This study highlights the importance of understanding the diverse genetic structures of SGI1-K and emphasizes the role of animals and humans in the emergence of antimicrobial resistance.

Integron distribution and relationship to antimicrobial resistance in E. coli isolated from blood culture.

PURPOSE: The aim of this study was to evaluate the distribution of integrons in strains of E. coli isolated from blood culture and the relationship between integrons and antimicrobial resistance. METHODS: The study included 100 E. coli strains sent to the Medical Microbiology Laboratory from different clinics between September 2022 and June 2023. Antibiotic susceptibility was evaluated according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST). The presence of integrons was determined by the inhouse polymerase chain reaction (PCR). RESULTS: Integron positivity was detected in 45 (45%) of isolates, and class 1 integrons were found in 41 (41%), class 2 integrons in 2 (2%), and both class 1 integrons and class 2 integrons in 2 (2%). Class 3 integron positivity was not detected. In total, 63 cases of community origin and 37 cases of hospital origin were identified. When antibiotic resistance was evaluated, the highest sensitivity was noted for amikacin (1%), meropenem (5%), imipenem (6%), and the highest resistant antibiotics were ampicillin (82%), cepfuroxime sodium (65%), and amoxicillin/clavulanate (62%), respectively. Of the 16 antimicrobial substances evaluated, 10 had an antibiotic resistance rate of over 45%. In class 1 integron-positive samples, ampicillin resistance and trimethoprim/sulfamethoxazole resistance were higher than in negative samples (p = 0.02, p = 0.0001, respectively). Fifty-one (51%) samples were found to have multiple drug resistance (MDR). In total, 59.5% of hospital-acquired isolates and 46% of community-acquired isolates were considered to be MDR. The class 1 integron positivity in MDR samples was high (p = 0.038). CONCLUSION: The high MDR rates in both hospital-acquired and community-acquired isolates are alarming. In particular, class 1 integron monitoring is very important to prevent the spread of MDR isolates.

Bacteriological and molecular study of fosfomycin resistance in uropathogenic Escherichia coli.

The identification of genes associated with resistance has the potential to facilitate the development of novel diagnostic tests and treatment methods. The objective of this study was to examine the antibiotic resistance and Fosfomycin resistance genes in uropathogenic Escherichia coli (UPEC) in patients in Baghdad, Iraq. After analyzing 250 urine samples using various identification methods, including the examination of morphological characteristics, biochemical tests, and genetic detection, it was determined that E. coli was the most common bacteria present, accounting for 63.6% of the samples. Antibiotic susceptibility testing showed a significant prevalence of resistance to various antibiotics, with 99.3% of E. coli isolates exhibiting multiple drug resistance (MDR). Fosfomycin showed antibacterial properties against UPEC. The minimum inhibitory concentration (MIC) ranged from 512 to 1024 µg/mL, while the minimum bactericidal concentration (MBC) was 2048 µg/mL. In the time-kill assay, fosfomycin was effective against fosfomycin-resistant isolates within 8-12 h. The genetic determinants associated with fosfomycin resistance were examined through the utilization of polymerase chain reaction (PCR). The findings indicated that the genes murA, glpT, and cyaA were detected in all the isolates when genomic DNA was used as a template. However, all the tests yielded negative results when plasmid was used as a template. The genes fosA3 and fosA4 were detected in 8.6% and 5% of the isolates when genomic DNA was used as a template. When plasmid was used as a template, the genes fosA3 and fosA4 were found in 5.7% and 2.9% of the isolates, respectively. In conclusion, there is an increasing problem with antibiotic resistance in UPEC, with elevated rates of resistance to several antibiotics. The study also offers novel insights into the genetic foundation of fosfomycin resistance in UPEC.

Antimicrobial resistance survey and whole-genome analysis of nosocomial P. Aeruginosa isolated from eastern Province of China in 2016-2021.

BACKGROUND: Pseudomonas aeruginosa is a major Gram-negative pathogen that can exacerbate lung infections in the patients with cystic fibrosis, which can ultimately lead to death. METHODS: From 2016 to 2021, 103 strains of P. aeruginosa were isolated from hospitals and 20 antibiotics were used for antimicrobial susceptibility determination. Using next-generation genome sequencing technology, these strains were sequenced and analyzed in terms of serotypes, ST types, and resistance genes for epidemiological investigation. RESULTS: The age distribution of patients ranged from 10 days to 94 years with a median age of 69 years old. The strains were mainly isolated from sputum (72 strains, 69.9%) and blood (14 strains, 13.6%). The size of these genomes ranged from 6.2 Mb to 7.4 Mb, with a mean value of 6.5 Mb. In addition to eight antibiotics that show inherent resistance to P. aeruginosa, the sensitivity rates for colistin, amikacin, gentamicin, ceftazidime, piperacillin, piperacillin-tazobactam, ciprofloxacin, meropenem, aztreonam, imipenem, cefepime and levofloxacin were 100%, 95.15%, 86.41%, 72.82%, 71.84%, 69.90%, 55.34%, 52.43%, 50.49%, 50.49%, 49.51% and 47.57% respectively, and the carriage rate of MDR strains was 30.69% (31/101). Whole-genome analysis showed that a total of 50 ST types were identified, with ST244 (5/103) and ST1076 (4/103) having a more pronounced distribution advantage. Serotype predictions showed that O6 accounted for 29.13% (30/103), O11 for 23.30% (24/103), O2 for 18.45% (19/103), and O1 for 11.65% (12/103) of the highest proportions. Notably, we found a significantly higher proportion of ExoU in P. aeruginosa strains of serotype O11 than in other cytotoxic exoenzyme positive strains. In addition to this, a total of 47 crpP genes that mediate resistance to fluoroquinolones antibiotics were found distributed on 43 P. aeruginosa strains, and 10 new variants of CrpP were identified, named 1.33, 1.34, 1.35, 1.36, 1.37, 1.38, 1.39, 1.40, 1.41 and 7.1. CONCLUSIONS: We investigated the antibiotic susceptibility of clinical isolates of P. aeruginosa and genomically enriched the diversity of P. aeruginosa for its prophylactic and therapeutic value.

Computational Study of Antimicrobial Peptides for Promising Therapeutic Applications Against Methicillin-resistant Staphylococcus Aureus.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a causative agent for multiple drug-resistant diseases and is a prime health concern. Currently, antibiotics like vancomycin, daptomycin, fluoroquinolones, linezolid, fifth-generation cephalosporin and others are available in the market for the treatment of MRSA infection. METHODS: With the increasing prevalence of drug-resistant cases, researchers are actively investigating alternative strategies to combat MRSA, including the exploration of peptide therapeutics. This study employed computational methods to prospect for potential Antimicrobial Peptides (AMPs). RESULTS: A total of One hundred and fifty antimicrobial peptides were explored based on physicochemical properties. The results showed that Clavanin B was the most appropriate candidate. Molecular Docking and Molecular Dynamics Simulation results showed the protein-peptide interaction of the MRSA target proteins, Penicillin Binding Protein 2a and Panton-Valentine Leukocidin Toxin, with the Antimicrobial Peptide Clavanin B. CONCLUSION: Currently, the antimicrobial peptide database highlights Clavanin B's role as an anti-HIV peptide. Moreover, this investigation proposes Clavanin B as a viable repurposed drug for treating MRSA, underscoring its potential deployment in the management of MRSA infections.

An Overview of the Global Alarming Increase of Multiple Drug Resistant: A Major Challenge in Clinical Diagnosis.

The increased spreading of antibiotic resistance among different infectious agents has been a fast-growing public health challenge worldwide; this is because of the discovery of new resistance mechanisms and the reduction in quality and effective treatments of general pathogenic infections. This has caused unsuccessful microbial responses to standard therapy, which could lead to a higher risk of mortality, prolonged illness, and more expenditures for health care. Most parasites, bacteria, fungi, and viruses can produce a higher degree of multidrug resistance (MDR) with increased mortality and morbidity. Moreover, the establishment of MDR can be a natural phenomenon, improper utilization of antimicrobial drugs, lack of proper sanitary conditions, poor method of food handling, and absence of infection prevention and control (IPC), which could be responsible for the further spreading of MDR. Moreover, MDR helminth's mechanism of action can occur via genetic alterations in the drug transport, metabolisms and target sites. MDR bacterial mode of action such as cell wall synthesis inhibitors, DNA synthesis inhibitors and so on. However, there have been different approaches to managing and preventing multi-drug resistance. Hence, this review's aim is to educate the public about the global increase of multiple drug resistance and the danger ahead if appropriate measures are not put in place to combat microbial infections.

Acori Tatarinowii Rhizoma prevents the fluoxetine-induced multiple-drug resistance of Escherichia coli against antibiotics.

BACKGROUND: In treating depression, the residual anti-depressant in gut interacts with the microbiome, leading to the appearance of multiple drug resistant (MDR) mutants, which poses a challenge for the treatment of infectious complications. Strategy is needed to combat this issue. Acori Tatarinowii Rhizoma (ATR, rhizome of Acorus tatarinowii Schott, Araceae), a traditional Chinese medicine, has been widely used for treatment of neurological disorders and gastrointestinal digestive disease in China. Here, ATR was demonstrated an excellent MDR-preventing effect in fluoxetine-induced Escherichia coli (E. coli). AIM OF THE STUDY: This study aimed to reveal the effective role of ATR and its signaling cascades involved in preventing fluoxetine-induced MDR. MATERIALS AND METHODS: The water extract of ATR was co-applied with sub-minimum inhibitory concentration (100 mg/l) of fluoxetine in E. coli to evaluate its anti-MDR potential. Formation of reactive oxygen species (ROS) and expression of MDR-related genes in bacteria were measured by dichloro-dihydro-fluorescein diacetate assay and real-time PCR, respectively. Two fluorescent dyes, 1-N-phenylnapthylamine and 3,3'-dipropylthiadicarbocyanine were used to analyze the outer membrane permeability and inner membrane depolarization of E. coli. The accumulation of fluoxetine in the treated E. coli was determined via HPLC. The active fraction of ATR was identified. RESULTS: The water extract of ATR significantly decreased the number of MDR mutants induced by fluoxetine and had half effective concentrations (EC50) of 55.5 µg/ml and 16.8 µg/ml for chloramphenicol and tetracycline, respectively. ATR robustly reversed the fluoxetine-induced superoxide response and membrane damage in E. coli. In addition, the inclusion of ATR significantly reduced the accumulation of fluoxetine in E. coli. After further fractionation, the polysaccharide of ATR was demonstrated as the fraction with the most significant anti-MDR activity. CONCLUSIONS: This is the first report to investigate the MDR-preventing effect of ATR. The results of this study proposed ATR as an excellent herbal product to prevent MDR issues, as induced by fluoxetine, with the potential to reduce the side effects during the drug therapy of depression.

Screening for multidrug-resistant organisms in high-risk hospitalized patients with hematologic diseases.

OBJECTIVES: Patients treated for hematologic malignancies are at higher risk for blood stream infections (BSI) and multidrug-resistant organisms (MDRO) are increasingly involved. Studies showed a significant association between rectal colonization status and a higher risk of subsequent MDRO BSI. The objective of our study was to probe the practice of surveillance cultures in Belgian hematology centers. METHODS: A questionnaire was sent to the 13 hematology centers participating in the acute leukemia board of the Belgian Hematology Society. 21 questions probed for the method of surveillance cultures, MDRO screened, antimicrobial prophylaxis, and empirical therapy and their relationship with colonization status. RESULTS: All centers completed the questionnaire in full. Routine gastrointestinal surveillance cultures in hematologic patients are taken in 10 hospitals. Organisms tested for included mostly ESBL (n = 9) and carbapenem-resistant (n = 8) Enterobacterales. All centers with a screening strategy adapt empiric antibiotic therapy based on MDRO colonization. Prophylaxis strategies are variable, only two centers adapt prophylaxis upon documentation of fluoroquinolone resistance. CONCLUSIONS: The majority of the Belgian centers perform routine surveillance cultures and adapt empiric therapy for neutropenic fever accordingly. Other reasons for testing include to gain insight into local epidemiology and to prevent in-hospital transmission. In general, there was significant variability in surveillance dimensions.

Prevalence and antimicrobial resistance profile of pathogens isolated from patients with urine tract infections admitted to a university hospital in a medium-sized Brazilian city

ABSTRACT This study aimed to determine the antibiotic profile of microorganisms isolated from urine samples of patients with community urine tract infections (UTI) admitted to the University Hospital of the Federal University of Sao Carlos to support an appropriate local empirical treatment. A retrospective cross-sectional study was conducted from October 2018 to October 2020. Data from 1,528 positive urine cultures for bacterial pathogens and antibiograms were tabulated. Bacterial species prevalence and their resistance profile were analyzed and compared by sex and age. For Gram-negative fermenting bacteria, resistance rates were compared between patients with previous hospitalization and the total of infections caused by this group. For comparisons, the Chi-square test was performed, using Fisher's exact test when necessary (BioEstat program, adopting p ≤ 0.05). A multivariate analysis was applied to assess the effect of the studied variables in predicting multidrug resistance. Infections were more prevalent in women and older adults. Gram-negative bacteria represented 90.44% of total cultures. In both sexes, E. coli prevalence was significantly higher in adults compared with older adults (p < 0.0001). For several antibiotics, resistance rates were higher in the older adults compared with other ages and in patients with Gram-negative fermenting infections and previous hospitalization compared with the total of infections by this group of bacteria. The closer to the hospitalization, the higher the number of antibiotics with superior resistance rates. Resistance rates for aminoglycosides, carbapenems, ceftazidime, nitrofurantoin, piperacillin+tazobactam, and fosfomycin were less than 20%, considered adequate for empirical treatment. Only hospitalization in the previous 90 days was statistically significant in predicting infections by multidrug-resistant bacteria.

The secrets of environmental Pseudomonas aeruginosa in slaughterhouses: Antibiogram profile, virulence, and antibiotic resistance genes.

Environmental pollution is a serious problem that can cause sicknesses, fatality, and biological contaminants such as bacteria, which can trigger allergic reactions and infectious illnesses. There is also evidence that environmental pollutants can have an impact on the gut microbiome and contribute to the development of various mental health and metabolic disorders. This study aimed to study the antibiotic resistance and virulence potential of environmental Pseudomonas aeruginosa (P. aeruginosa) isolates in slaughterhouses. A total of 100 samples were collected from different slaughterhouse tools. The samples were identified by cultural and biochemical tests and confirmed by the VITEK 2 system. P. aeruginosa isolates were further confirmed by CHROMagar™ Pseudomonas and genetically by rpsL gene analysis. Molecular screening of virulence genes (fimH, papC, lasB, rhlI, lasI, csgA, toxA, and hly) and antibiotic resistance genes (blaCTX-M, blaAmpC, blaSHV, blaNDM, IMP-1, aac(6')-Ib-, ant(4')IIb, mexY, TEM, tetA, and qnrB) by PCR and testing the antibiotic sensitivity, biofilm formation, and production of pigments, and hemolysin were carried out in all isolated strains. A total of 62 isolates were identified as P. aeruginosa. All P. aeruginosa isolates were multidrug-resistant and most of them have multiple resistant genes. blaCTX-M gene was detected in all strains; 23 (37.1%) strains have the ability for biofilm formation, 33 strains had virulence genes, and 26 isolates from them have more than one virulence genes. There should be probably 60 (96.8%) P. aeruginosa strains that produce pyocyanin pigment. Slaughterhouse tools are sources for multidrug-resistant and virulent pathogenic microorganisms which are a serious health problem. Low-hygienic slaughterhouses could be a reservoir for resistance and virulence genes which could then be transferred to other pathogens.

Dynamics of antimicrobial resistance and virulence of staphylococcal species isolated from foods traded in the Cape Coast metropolitan and Elmina municipality of Ghana.

The impact of staphylococci on food poisoning and infections could be higher than previously reported. In this study, we characterised the occurrence and coexistence of antimicrobial resistance and virulence genes of staphylococci isolates in foods. Staphylococci were isolated from 236 samples of selected street-vended foods and identified. The pattern of antimicrobial resistance and virulence genes in the staphylococci were assessed using disc diffusion, PCR and analysis of next-generation sequencing data. The food samples (70.76 %) showed a high prevalence of staphylococci and differed among the food categories. Forty-five Staphylococcus species were identified and comprised coagulase-negative and positive species. Staphylococcus sciuri (now Mammaliicoccus sciuri), S. aureus, S. kloosii, S. xylosus, S. saprophyticus, S. haemolyticus and S. succinus were the most abundant species. The staphylococcal isolates exhibited resistance to tetracycline, levofloxacin, ciprofloxacin, norfloxacin, gentamicin and amikacin and susceptibility to nitrofurantoin. Antimicrobial susceptibilities were also reported for cefoperazone, ceftriaxone, cefotaxime, nalidixic acid and piperacillin-tazobactam. The antimicrobial resistance and virulence genes commonly detected consisted of tet, arl, macB, van, gyr, nor, optrA, bcrA, blaZ, taeA and S. aureus lmrS. The isolates frequently exhibited multiple resistance (30.42 %) of up to eight antimicrobial drug classes. The isolates predominantly harboured genes that express efflux pump proteins (50.53 %) for antibiotic resistance compared with inactivation (10.05 %), target alteration (26.72 %), protection (7.67 %) and replacement (3.17 %). The virulence determinants comprised genes of pyrogenic toxin superantigens (eta, etb, tst), adhesions (clf, fnbA, fnbB, cna, map, ebp, spA, vWbp, coa) and genes that express exoproteins (nuclease, metalloprotease, γ-hemolysin, hyaluronate lyase). There was a statistically significant difference in the prevalence of staphylococci isolates and their antimicrobial resistance and virulence profile as revealed by the phenotypic, PCR and next-generation sequencing techniques. The findings suggest a higher health risk for consumers. We recommend a critical need for awareness and antimicrobial susceptibility and anti-virulence strategies to ensure food safety and counteract the spread of this clinically relevant genus.

Beta-lactam, aminoglycoside, and quinolone resistance in Escherichia coli strains isolated from shrimps and mussels in the Marmara Sea.

The purpose of the study was to examine the prevalence of Escherichia coli in shrimps and mussels, and to determine the distribution of ß-lactam, aminoglycoside, quinolone, and multi-drug resistance phenotypically and genotypically in E. coli isolates obtained from mussels and shrimps in Istanbul. Faecal samples were collected from mussels (n = 96) and shrimps (n = 96) from the Marmara Sea coastline and fish markets in Istanbul. For the detection of antibiotic susceptibilities, seven antibiotic groups were used. ß-lactamase, aminoglycoside, and quinolone genes were also determined. A total of 34 (17.7%, 15 shrimps, and 19 mussels) E. coli were isolated, and 17 (50%) were found to be resistant to one or more antimicrobials. The highest resistance was seen against aminoglycosides with 11 isolates (32.35%), followed by quinolones with 10 isolates (29.41%) and extended-spectrum ß-lactamase (ESBL) with 4 isolates (11.76%). Multi-drug resistance was detected in 5 isolates (14.7%) from 3 shrimp and 2 mussel samples. The prevalence of ESBL genes was demonstrated at 3.84% in mussels and shrimp samples. There were no AmpC and carbapenemase-producing genes. These samples harbored blaCTX-M-1 (n = 3) and blaTEM (n = 4). Ten isolates were resistant to aminoglycosides genotypically. Resistance genes detected were strB in 2 isolates, aadA in 5, strB and aadA together in 3, ANT('')-Ia, aphA1 and aphA2 simultaneously in 3, aphA1 in 1, aac(3)-IIa in 1 isolate. aac(6')-Ib-cr gene was detected in only one of 10 phenotypically resistant isolates to quinolones.