Multiresistant Bacteria Research Articles

Rosmarinus officinalis essential oils’ eradication of beta-lactamase and multidrug resistant clinical bacterial pathogens from hospital settings

Antibiotics have become increasingly ineffective in the face of bacterial resistance, particularly in hospitals. Interestingly, there is high demand for bioprospecting of secondary metabolites, particularly for treating multidrug-resistant clinical diseases. In fact, Rosemary has been used for its antiseptic properties dating back to antiquity. The aim of this research is to evaluate the effectiveness of Rosmarinus officinalis essential oil against multidrug-resistant clinical bacterial pathogens. Results showed promising antibacterial activity against seven bacteria: Escherichia coli, Enterobacter cloacae, Staphylococcus aureus, Serratia odorifera, Klebsiella pneumoniae, Klebsiella oxytoca, Aeromonas hydrophila with MIC values of 35.7, 17.85, 71.4, 8.9, 17.8, 285.7, 35.7 µg/ml respectively and MBC values of 142.8, 71.4, 285.7, 35.7, 71.4, 571.5,71.4 µg/ml respectively. This study suggests that Rosmarinus essential oil can be used as a therapeutic agent in the fight against a wide range of multi-resistant bacteria.

Shewanella subflava sp. nov., a novel multi-resistant bacterium, isolated from the estuary of the Fenhe River into the Yellow River.

A aerobic, gram-negative, rod-shaped and polar-flagellum bacterial strain, designated as FYR11-62T, was isolated from the estuary of the Fenhe River into the Yellow River in Shanxi Province, China. The isolate was able to grow at 4-37°C (optimum, 25°C), pH 5.5-9.5 (optimum, pH 7.5) and in the presence of 0-7.0% (w/v) NaCl (optimum, 1.0% NaCl). Phylogenetic analyses based on 16S rRNA genes and 1597 single-copy orthologous clusters indicated that strain FYR11-62T affiliated with the genus Shewanella and shared the highest 16S rRNA gene sequence similarity to Shewanella aestuarii SC18T (98.3%) and Shewanella gaetbuli TF-27T (97.3%), respectively. The major fatty acids were summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), C16:0 and iso-C15:0. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. The main quinones were Q-7 and Q-8. The genomic DNA G + C content was 41.6%. Gene annotation showed that strain FYR11-62T possessed 30 antibiotic resistance genes, implying its multiple antidrug resistance. The average nucleotide identity and digital DNA-DNA hybridization values between strain FYR11-62T and its closely related species were all below the thresholds for species delineation. The phylogenetic position together with the results of the analysis of morphological, physiological and genomic features support the classification of strain FYR11-62T (= MCCC 1K07242T = KCTC 92244T) as a novel species of the genus Shewanella, for which the name Shewanella subflava sp. nov. is proposed.

MP08-04 USE OF ANTIBIOTICS IN PATIENTS UNDERGOING FOLLOW-UP FOR NON-MUSCLE INVASIVE BLADDER CANCER WITH EITHER FLEXIBLE CYSTOSCOPY OR THE URINARY BIOMARKER TEST XPERT® BLADDER CANCER MONITOR: A SECONDARY OUTCOME FROM A RANDOMISED CLINICAL TRIAL

You have accessJournal of UrologyCME1 Apr 2023MP08-04 USE OF ANTIBIOTICS IN PATIENTS UNDERGOING FOLLOW-UP FOR NON-MUSCLE INVASIVE BLADDER CANCER WITH EITHER FLEXIBLE CYSTOSCOPY OR THE URINARY BIOMARKER TEST XPERT® BLADDER CANCER MONITOR: A SECONDARY OUTCOME FROM A RANDOMISED CLINICAL TRIAL Thomas Dreyer, Simone Brandt, Knud Fabrin, Nessn Azawi, Juan Luis Vásquez, Andreas Ernst, Lars Dyrskjøt, and Jørgen Bjerggaard Jensen Thomas DreyerThomas Dreyer More articles by this author , Simone BrandtSimone Brandt More articles by this author , Knud FabrinKnud Fabrin More articles by this author , Nessn AzawiNessn Azawi More articles by this author , Juan Luis VásquezJuan Luis Vásquez More articles by this author , Andreas ErnstAndreas Ernst More articles by this author , Lars DyrskjøtLars Dyrskjøt More articles by this author , and Jørgen Bjerggaard JensenJørgen Bjerggaard Jensen More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003223.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Patients with non-muscle-invasive bladder cancer (NMIBC) have a high recurrence rate, which leads to frequent flexible cystoscopies (FC). Aside from the burden of undergoing FC, there is a risk of urinary tract infection (UTI) following FC. Follow-up of NMIBC with non-invasive urinary biomarker tests could reduce the number of FCs, and thus potentially the need for antibiotics due to UTI. Furthermore, because UTIs are among the most common infections, any reduction in incidence could reduce development of multiresistant uropathogenic bacteria.In this study, a secondary outcome from the DaBlaCa-15 trial is reported. The objective was to compare the number of patients with collected prescriptions for antibiotics for UTI in patients followed with FC versus patients followed primarily with the urinary biomarker test Xpert® Bladder Cancer Monitor (XBCM) (CE-IVD. In Vitro Diagnostic Medical Device. May not be available in all countries. Not available in the United States.). METHODS: A two-arm randomised non-inferiority trial enrolling 392 patients with previous high-grade NMIBC was conducted. In the intervention arm, patients were followed with XBCM every four months with only one yearly pre-scheduled FC. Patients in the control arm underwent FC every four months for two years. The number of patients who collected prescriptions for UTI during the study period was compared both peri- and post-FC and for visits where a FC was not pre-scheduled. RESULTS: During follow-up, 23.7% of patients in the intervention arm collected a prescription compared to 31.0% in the control arm (RR 0.76; 95% CI 0.55-1.06; p=0.11). When analysing visits without a pre-scheduled FC, 6.3% of patients in the intervention arm collected a prescription in the 14 days after a visit versus 13.4% in the control arm (RR 0.47; 95% CI 0.25-0.90; p=0.02). Similarly, the peri-FC use of antibiotics was 7.9% in the intervention arm, compared to 15.0% in the control arm (RR 0.53; 95% CI 0.29-0.94; p=0.03). A reduction in the number of FCs performed in the intervention arm was observed (39.1% versus 98.3%; p<0.0001). CONCLUSIONS: The findings of the present study support the hypothesis that replacing cystoscopy with XBCM can reduce the use of antibiotics for UTI during follow-up of NMIBC. Thus, the morbidity of follow-up of NMIBC with FC can be reduced, resulting perhaps in less development of multiresistant uropathogenic bacteria and increased quality of life. Source of Funding: Supported by Cepheid Inc. © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e94 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Thomas Dreyer More articles by this author Simone Brandt More articles by this author Knud Fabrin More articles by this author Nessn Azawi More articles by this author Juan Luis Vásquez More articles by this author Andreas Ernst More articles by this author Lars Dyrskjøt More articles by this author Jørgen Bjerggaard Jensen More articles by this author Expand All Advertisement PDF downloadLoading ...

Evaluating the Synergistic Potency of Essential Oils and Antibiotics Against Klebsiella pneumoniae BLSE Strains.

Klebsiella pneumoniae producing extended-spectrum β-lactamases (ESBL) continues to pose huge therapeutic challenges in the treatment of infections, primarily urinary infections, due to its multidrug resistance to antibiotics. Therefore, there is a need for research on this topic to investigate ways to reduce the spread of antibiotic resistance, identify novel therapeutic approaches to treat these infections and gain a better understanding of the mechanisms of resistance. In this context, this study aimed to analyze the chemical composition of essential oils (EOs) of Thymus algeriensis, Syzygium aromaticum, and Eucalyptus globulus and assess their activity against K. pneumoniae ESBL strains, as well as the interaction type between these EOs and antibiotics used for the treatment of K. pneumoniae ESBL infections. The composition of the EOs was determined by gas chromatography-mass spectrometry (GC-MS). The activity of EOs was tested using the disc diffusion and liquid microdilution methods. The type of interaction between EOs and antibiotics was studied using the agar disk diffusion and chessboard methods. The analysis of the EO of T. algeriensis showed that the main compounds were thymol (23.14%), linalool (18.44%), and p-cymene (16.17%). The main constituents of EO of E. globulus were eucalyptol (54.29%), α-pinene (17.32%), aromadendrene (7.02%), and pinocarveol (6.32%). As for the EO of S. aromaticum, the major constituents were eugenol (80.46%) and eugenol acetate (16.23%). Results of the activity tests showed that all three EOs were active against the tested strains, with inhibition diameters ranging from 7.39±0.44mm to 32.4±1.05mm and minimum inhibitory concentrations (MICs) varying from 2 to 441.5±5.66 mg/ml. A synergistic interaction was obtained between amoxicillin-clavulanic acid and T. algeriensis EO against two strains of K. pneumoniae ESBL. These results demonstrate the potential of our EOs to inhibit multi-resistant pathogenic ESBL strains, as well as their synergistic interaction with antibiotics used in therapy, which could be an alternative to the use of antibiotics alone in treatment to fight against these multi-resistant pathogenic bacteria.

Description of Antimicrobial Resistance Patterns at the National Institute of Hygiene in Lome, Togo.

The monitoring of antimicrobial resistance has become a priority, mainly in developing countries, to control the emergence of multidrug-resistant bacterial strains. This study evaluated the antibiotic resistance profiles of bacteria isolated at the National Institute of Hygiene in Togo. The laboratory records from January 2013 to December 2015 were examined, which showed that a total of 33,147 samples had been analyzed. Among them, vaginal swabs and urine samples were predominant, amounting to 38.17% and 33.24%, respectively. In total, 3,497 Gram-positive and 1,970 Gram-negative bacterial strains were cultured. Enterobacteriaceae (57.6%), Staphylococcus spp. (21.1%), and Streptococcus spp. (10.5%) were primarily isolated. The records showed that over 3 years, Escherichia coli was resistant to piperacillin (79.66%, 75.1%, and 83%), trimethoprim/sulfamethoxazole (79.3%, 82%, and 82.8%), ticarcillin (89%, 89.7%, and 93%), and amoxicillin (94.1%, 94%, and 96.09%), whereas Staphylococcus aureus was resistant to penicillin G. Streptococcaceae isolates were resistant to trimethoprim/sulfamethoxazole (78.11-87.1%), tetracycline (82.2-91.16%), and norfloxacin (86.16-94.3%). Escherichia coli and S. aureus isolated from urine were more resistant to antibiotics than those isolated from vaginal swabs. There is a need to develop new strategies to fight the emergence of multi-resistant bacteria in Togo.

Multiresistant Bacteria in Neonatal Intensive Care and the Contribution of Molecular Biology

Epigenetics is a very active field of research today. This is a mechanism by which environmental factors can influence gene expression. Indeed, epigenetics has been defined as a new science aimed at studying the mechanisms by which the genotype generates the phenotype, without there being any modifications in the DNA sequence. In this context, we conducted a prospective study on the records of 523 patients hospitalized in the neonatal intensive care unit of the CHU Mohamed VI in Marrakech, over a period of 6 months, from July 01, 2019 to December 31, 2019. Main results obtained were as follows: A high MRB carriage rate affecting 45.5% of hospitalized patients during the study period. Late MRB infections are an important part of this. The analysis of the risk factors of these infections had demonstrated the major role of invasive procedures, in particular mechanical ventilation and KTVO, as well as the high duration of hospitalization which was on average 17.47 days in our study. The bacteriological profile was dominated by enterobacteriaceae, particularly K. pneumoniae and E. cloacae. Of all the MRBs sent to the Kremlin Bicêtre hospital, 55 strains were analyzed by MLST; including 36 strains of K. pneumonia and 19 strains of E. cloacae. The Enterobacteriaceae strains analyzed in our study were mainly carbapenemase producers, of the NDM and OXA-48 type, and ESBL type CTX-15M. Of all the bacterial clones identified, a high rate of resistance to antibiotics, in particular carbapenems, was noted in the following clones: ST 1805, ST 1158 and ST 307. The ST 1805 clone was exclusively found in our series.

Structural basis of the inhibition of cystathionine γ-lyase from Toxoplasma gondii by propargylglycine and cysteine.

Cystathionine γ-lyase (CGL) is a PLP-dependent enzyme that catalyzes the last step of the reverse transsulfuration route for endogenous cysteine biosynthesis. The canonical CGL-catalyzed process consists of an α,γ-elimination reaction that breaks down cystathionine into cysteine, α-ketobutyrate, and ammonia. In some species, the enzyme can alternatively use cysteine as a substrate, resulting in the production of hydrogen sulfide (H2 S). Importantly, inhibition of the enzyme and consequently of its H2 S production activity, makes multiresistant bacteria considerably more susceptible to antibiotics. Other organisms, such as Toxoplasma gondii, the causative agent of toxoplasmosis, encode a CGL enzyme (TgCGL) that almost exclusively catalyzes the canonical process, with only minor reactivity to cysteine. Interestingly, the substitution of N360 by a serine (the equivalent amino acid residue in the human enzyme) at the active site changes the specificity of TgCGL for the catalysis of cystathionine, resulting in an enzyme that can cleave both the CγS and the CβS bond of cystathionine. Based on these findings and to deepen the molecular basis underlying the enzyme-substrate specificity, we have elucidated the crystal structures of native TgCGL and the variant TgCGL-N360S from crystals grown in the presence of cystathionine, cysteine, and the inhibitor D,L-propargylglycine (PPG). Our structures reveal the binding mode of each molecule within the catalytic cavity and help explain the inhibitory behavior of cysteine and PPG. A specific inhibitory mechanism of TgCGL by PPG is proposed. This article is protected by copyright. All rights reserved.

Predominance of Multidrug-Resistant Gram-Negative Bacteria on Contaminated Surfaces at a Tertiary Hospital in Tanzania: A Call to Strengthening Environmental Infection Prevention and Control Measures.

The spreading of multidrug resistance (MDR) strains in the hospital settings via contaminated surfaces have been increasingly reported where Gram-negative bacteria have been implicated in causing most nosocomial infections. This study aimed to determine the rate of contamination with multi-resistant gram-negative bacteria in the hospital environment. A cross-sectional study was conducted at Muhimbili National Hospital paediatric department, between July and August 2020. Non-repetitive surface swab samples were collected from predefined surfaces and medical device surfaces, and cultured on MacConkey agar with and without antibiotics. Isolates were identified using biochemical test and tested for antibiotic susceptibility using the Kirby-Bauer disk diffusion method. The rate of hospital contamination with Gram-negative bacteria across the Pediatrics units was 30%, with a high rate observed in oncology units (34.8%) and the malnutrition/diarrhoea ward (32.1%). Sink/washing basin had the highest frequency of bacterial contamination (74.2%). We observed a high rate of ESBL (32.5%), with Acinetobacter baumannii, Klebsiella pneumoniae, and E. coli being the predominant ESBL-producing Gram-negative bacteria, while carbapenemase-producing Gram-negative bacteria was detected at 22.8%. Highest resistance rates (63-100%) were observed against ceftriaxone and trimethoprim-sulfamethoxazole. Up to 51% of the Gram-negative bacteria showed resistant to meropenem. MDR strains were detected in 61.4% of Gram-negative bacteria isolated. In conclusion, we observed a high rate of MDR bacteria contaminating hospital surfaces. The higher rate of MDR calls for a need to strengthen infectious prevention control measures, including cleaning practices in the hospital environment, to reduce the risk of transmission of resistant strains to patients and healthcare workers.

Staphylococcus aureus binding to Seraph® 100 Microbind® Affinity Filter: Effects of surface protein expression and treatment duration.

Extracorporeal blood purification systems represent a promising alternative for treatment of blood stream infections with multiresistant bacteria. The aim of this study was to analyse the binding activity of S. aureus to Seraph affinity filters based on heparin coated beads and to identify effectors influencing this binding activity. To test the binding activity, we used gfp-expressing S. aureus Newman strains inoculated either in 0.9% NaCl or in blood plasma and determined the number of unbound bacteria by FACS analyses after passing through Seraph affinity filters. The binding activity of S. aureus was clearly impaired in human plasma: while a percent removal of 42% was observed in 0.9% NaCl (p-value 0.0472) using Seraph mini columns, a percent removal of only 10% was achieved in human plasma (p-value 0.0934). The different composition of surface proteins in S. aureus caused by the loss of SarA, SigB, Lgt, and SaeS had no significant influence on its binding activity. In a clinically relevant approach using the Seraph® 100 Microbind® Affinity Filter and 1000 ml of human blood plasma from four different donors, the duration of treatment was shown to have a critical effect on the rate of bacterial reduction. Within the first four hours, the number of bacteria decreased continuously and the reduction in bacteria reached statistical significance after two hours of treatment (percentage reduction 64%, p-value 0.01165). The final reduction after four hours of treatment was close to 90% and is dependent on donor. The capacity of Seraph® 100 for S. aureus in human plasma was approximately 5 x 108 cells. The Seraph affinity filter, based on heparin-coated beads, is a highly efficient method for reducing S. aureus in human blood plasma, with efficiency dependent on blood plasma composition and treatment duration.

Risk of bloodstream infections in allogeneic hematopoietic cell transplant recipients according to gut mucosal colonization and fluoroquinolone implementation during neutropenia

Background . Higher rate of gram-negative bloodstream infections (BSI) have been recently documented from transplantation centers providing fluoroquinolone (FQ) prophylaxis. Aim . To define the incidence of BSI during neutropenia according to gut mucosal colonization with resistant gramnegative bacteria and FQ administration. Materials and methods . Of 284 allogeneic hematopoietic cell transplant recipients included in the study, 154 (54.2 %) were identified as colonized with resistant gram-negative bacteria, and 130 (45.8 %) patients as non-colonized. Resistant gram-negative bacteria included Enterobacterales with extended spectrum beta-lactamase production, carbapenem-resistant Enterobacterales, Stenotrophomonas maltophilia , and carbapenem-resistant strains of Pseudomonas aeruginosa . Colonized patients did not receive FQ prophylaxis (n = 147) except 7 patients who received FQ as sequential therapy due to residual inflammatory lung lesions. Among non-colonized patients 98 received FQ prophylaxis, whereas 32 did not. Results . Probability of gram-negative BSI (71.4 %; p &lt;0.0001), and extended spectrum beta-lactamase-producing Enterobacterales BSI (57.1 %; p &lt;0.0001) was significantly higher in colonized patients receiving FQ. No significant difference was found in probability of gram-positive BSI (p = 0.452). In multivariate analysis colonized patients with (hazard ratio (HR) 35.32; 95 % confidence interval (CI) 9.15–136.44; p &lt;0.0001) or without FQ (HR 3.44; 95 % CI 1.15–10.31; p = 0.007), omission of FQ in non-colonized patients (HR 4.03; 95 % CI 1.08–15.00; p = 0.038), and active disease before allogeneic hematopoietic cell transplantation (HR 2.17; 95 % CI 1.03–4.63; p = 0.042) were associated with higher risk of gram-negative BSI, whereas mismatched unrelated donor transplantations were associated with higher gram-positive BSI risk (HR 3.84; 95 % CI 1.63–9.08; p = 0,009). Conclusion . Colonization with multiresistant gram-negative bacteria is a predictor of gram-negative BSI, including multiresistant pathogens, especially when FQ are prescribed during neutropenia, while in non-colonized patients FQ prophylaxis is an effective approach significantly reducing gram-negative BSI.

Antibiotic consumption and antimicrobial resistance in the SARS-CoV-2 pandemic: A single-center experience.

Introduction: Antimicrobial resistance and the rapid spread of multiresistant bacteria represent one of the main public health problem in limited resources countries. This issue is significantly worsening since the COVID-19 pandemic due to the unreasonably increased antibiotics prescription to patients with confirmed SARS-CoV-2 infection. The aim of this study was to examine whether COVID-19 pandemic (2020, 2021) was associated with increased antibiotic consumption in inpatient and outpatient settings in the middle size urban region (Republic of Srpska/Bosnia and Herzegovina) in comparison to period before the pandemic (2019). Additionally, we aimed to determine antimicrobial resistance and the presence of multiresistant bacteria in the regional hospital ("Saint Apostol Luka" Hospital Doboj) in 2021. Methodology: The consumption of antibiotics in inpatient was calculated as Defined Daily Dose per one hundred of patient-days. The consumption of antibiotics in outpatient was calculated as Defined Daily Dose per thousand inhabitants per day. Resistance of bacteria to antibiotics is expressed as a rates and density for each observed antibiotic. The rate of resistance was calculated as a percentage in relation to the total number of isolates of individual bacteria. The density of resistance of isolated bacteria against a specific antibiotic was expressed as the number of resistant pathogens/1000 patient days. Results: Antibiotic consumption in hospital setting registered during 2019, 2020 and 2021 was as follows: carbapenems (meropenem: 0.28; 1.91; 2.33 DDD/100 patient-days, respectively), glycopeptides (vancomycin: 0.14; 1.09, 1.54 DDD/100 patient-days, respectively), cephalosporins (ceftriaxone: 6.69; 14.7; 14.0 DDD/100 patient-days, respectively) and polymyxins (colistin: 0.04; 0.25; 0.35 DDD/100 bed-days, respectively). Consumption of azithromycin increased drastically in 2020, and dropped significantly in 2021 (0.48; 5.61; 0.93 DDD/100 patient-days). In outpatient setting, an increase in the consumption of oral forms of azithromycin, levofloxacin and cefixime, as well as parenteral forms of amoxicillin-clavulanic acid, ciprofloxacin and ceftriaxone, was recorded. In 2021, antimicrobial resistance to reserve antibiotics in hospital setting was as follows: Acinetobacter baumanii to meropenem 66.0%, Klebsiella spp to cefotaxime 67.14%, Pseudomonas to meropenem 25.7%. Conclusion: Recent COVID-19 pandemic was associated with increased antibiotic consumption in inpatient and outpatient settings, with characteristic change of pattern of azithromycin consumption. Also, high levels of antimicrobial resistance to reserve antibiotics were registered in hospital setting with low prevalence of identified pathogen-directed antimicrobial prescription. Strategies toward combat antimicrobial resistance in the Doboj region are urgently needed.

Evaluation of a rapid combination disc test (RCDT) for direct phenotypic detection of extended-spectrum β-lactamase production in E. coli from positive blood culture bottles.

The spread of multi-resistant bacteria endangers the effectiveness of empirical antimicrobial treatment, particularly in Gram-negative bloodstream infections. Thus, rapid and reliable susceptibility testing has become a key challenge of modern microbiology. Here, we evaluated a combination disc test for rapid detection of ESBL production in Escherichia coli (rapid combination disc test, RCDT) directly from blood cultures. RCDT with discs containing cefotaxime and ceftazidime alone or in combination with clavulanic acid was validated using a cryo-collection of 96 third-generation cephalosporin-resistant (3GCR), whole-genome sequenced E. coli isolates spiked into blood culture bottles. All isolates were subjected to RCDT and rapid antibiotic susceptibility testing (RAST). Zone diameters were assessed after 4, 6 and 8 h of incubation. All isolates also underwent conventional combination disc testing. The real-life performance of RCDT was assessed by analysis of 306 blood cultures growing E. coli. Eighty of 90 (88.9%) ESBL-positive E. coli validation isolates were correctly identified by RCDT after 4 h of incubation. The detection rate increased to 100% after 6 and 8 h. RCDT was negative in six 3GCR E. coli isolates expressing class B or C β-lactamases. RCDT from routine blood cultures correctly classified all 56 ESBL producers and 245/250 ESBL-negative isolates after 4 h, resulting in 100% sensitivity and 98.8% specificity. RCDT is a reliable method for rapid ESBL detection in E. coli directly from positive blood cultures. RCDT might complement RAST to support antibiotic stewardship interventions and treatment decisions.

Recent Developments in the Inhibition of Bacterial Adhesion as Promising Anti-Virulence Strategy.

Infectious diseases caused by antimicrobial-resistant strains have become a serious threat to global health, with a high social and economic impact. Multi-resistant bacteria exhibit various mechanisms at both the cellular and microbial community levels. Among the different strategies proposed to fight antibiotic resistance, we reckon that the inhibition of bacterial adhesion to host surfaces represents one of the most valid approaches, since it hampers bacterial virulence without affecting cell viability. Many different structures and biomolecules involved in the adhesion of Gram-positive and Gram-negative pathogens can be considered valuable targets for the development of promising tools to enrich our arsenal against pathogens.

The impact of the COVID pandemic on the uropathogenic bacterial resistance profile: Experience of the bacteriology lab of the military hospital Avicenne in Marrakech

The aim of this study is to define the uropathogenic bacterial resistance and to clarify how the COVID 19 pandemic has affected the development of bacterial resistance. Patients and methods: We conducted a retrospective analysis of the bacterial profile and antibiotic resistance status of the main isolates of uropathogens at the laboratory of microbiology at the military hospital Avicenne in Marrakech over the course of two time periods: the first was prior to COVID 19 (January 2019 to February 2020), and the second was one year later (January 2021 to February 2022). Results: In the first phase of the study, out of 4000 ECBU intended for the bacteriology lab, 581 met the criteria for a urinary tract infection. In the second phase of the study, out of 4692 ECBU requested, 590 samples were found to be positive, with a rate of incidence of 15%. For the two times, the Enterobacteries made up 80% of all the isolated bacteria. The total number of multiresistant bacteria (BMR) discovered on the ECBU's isolats during the course of the two study periods is 153, or 6.5% of the total isolats. Conclusion: This study made Escherichia coli the bacteria most implicated in the epidemiology of urogenital infections during the two periods. In the majority of cases, rates of resistance to various antibiotics increased during the COVID pandemic compared to the same time period two years earlier.

Antimicrobial Pharmacokinetics and Pharmacodynamics in Critical Care: Adjusting the Dose in Extracorporeal Circulation and to Prevent the Genesis of Multiresistant Bacteria

Critically ill patients suffering from severe infections are prone to pathophysiological pharmacokinetic changes that are frequently associated with inadequate antibiotic serum concentrations. Minimum inhibitory concentrations (MICs) of the causative pathogens tend to be higher in intensive care units. Both pharmacokinetic changes and high antibiotic resistance likely jeopardize the efficacy of treatment. The use of extracorporeal circulation devices to support hemodynamic, respiratory, or renal failure enables pharmacokinetic changes and makes it even more difficult to achieve an adequate antibiotic dose. Besides a clinical response, antibiotic pharmacokinetic optimization is important to reduce the selection of strains resistant to common antibiotics. In this review, we summarize the present knowledge regarding pharmacokinetic changes in critically ill patients and we discuss the effects of extra-corporeal devices on antibiotic treatment together with potential solutions.

Pilot Study on the Action of Thymus vulgaris Essential Oil in Treating the Most Common Bacterial Contaminants and Salmonella enterica subsp. enterica Serovar Derby in Poultry Litter.

The indiscriminate use of antimicrobials in poultry farms is linked to the increase in multi-resistant bacteria. Accordingly, based on the antimicrobial properties of Thyme Essential Oil (TEO), the present study evaluated the effects of TEO on the reduction of common microbial contaminants and Salmonella on poultry litter. A litter bulk sample was collected in a broiler farm and qualitative/quantitative investigations identified Escherichia coli and Mammaliicoccus lentus. The experimental contamination with Salmonella Derby wild strain was also performed. All pathogens showed phenotypic and genotypic resistance to different classes of antibiotics. The litter, split in different units, was treated with aqueous solutions of TEO at different concentrations (5% to 1.25%), demonstrating its effectiveness in reducing the total number of bacteria. The strongest antibacterial action was observed at the lowest concentration against Enterobacteriaceae, with a growth reduction compared to the positive control of 73.3% and 77.8% against E. coli and Salmonella Derby, respectively, while towards M. lentus the reduction was 50%. Our data confirm the antimicrobial activity of TEO and suggest its possible application for the treatment of poultry litter as an effective and natural approach for the prevention of diseases caused by the most common bacteria that colonize poultry farms, counteracting the onset of antibiotic resistance.

Occurrence of Antibiotic Resistance Genes, Antibiotics-Resistant and Multi-Resistant Bacteria and Their Correlations in One River in Central-Western Brazil

(1) Background: The uncontrolled increase in pollutants in the aquatic environment results in antibiotic-resistant bacteria and antibiotic resistance genes (ARBs and ARGs). The overuse and misuse of antibiotics is also a crucial factor for public health. (2) Methods: In this study, the presence of ARBs and the presence of 24 resistance genes from eight different classes of antibiotics were evaluated in addition to performing statistical correlations and intercorrelations. Samples of water and sediment were collected from a river in central-western Brazil, responsible for supplying water to more than 3 million people. Physicochemical analyses were performed on the water samples, as well as methodological approaches based on culture and molecular biology, such as real-time polymerase chain reaction (qPCR). (3) Results: The results of the analysis of apparent color, turbidity, thermotolerant coliforms and E. coli were not in accordance with Brazilian legislation. A total of 203 bacterial strains were isolated, of which 30.54% were from the Entero-bacteriaceae family and 29.06% from the Staphylococcaceae family. For the ARBs found, a higher prevalence of resistance to lyconsamides and β-lactams was detected. Among all isolated strains, a multi-drug resistance profile of 59.37% was found. The presence of ARGs was detected in all water and sediment samples; of the 24 genes searched, the presence of 22 was found, and the sul2 and ermC genes were detected in all samples. According to the statistical analysis, the Meia Ponte River is suffering a great anthropogenic impact, and the current Brazilian legislation is not sufficient to prevent it. This water environment is serving as a reservoir of resistance genes, and measures such as monitoring, depollution, management and preservation must be taken, so that the population does not suffer great damage. (4) Conclusions: This is the first study in the State of Goiás, Brazil, to indicate the existence of ARGs in samples of raw water and river sediments, supporting the worldwide investigation of ARBs and ARGs in a water environment. In addition, few studies address the correlations between the ARBs and ARGs groups, which is an important factor in the field of antimicrobial resistance.

Identification of Risk Factors for Nasal Colonization of Methicillin-resistant Staphylococcus aureus and Vancomycin-resistant Staphylococcus aureus in Health Workers at a Tertiary Hospital, Indonesia

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) and Vancomycin-resistant S. aureus (VRSA) frequently cause nosocomial infections yearly. During the COVID-19 pandemic, the potential for excessive use of antibiotics is a global threat to the increasing incidence of multiresistant bacteria. AIM: This study aimed to determine MRSA and VRSA colonization and identify factors associated with the risk of MRSA and VRSA nasal colonization in health workers at Dr. Soemarno Sosroatmodjo General Hospital, Kuala Kapuas, as one of the type C hospitals in Indonesia. METHODS: This cross-sectional analytic study at Dr. Soemarno Sosroatmodjo General Hospital, a tertiary hospital in Indonesia. A 128 health workers’ subjects had undergone nasal swab screening for MRSA and VRSA colonization examinations. Then, they were asked to complete a questionnaire concerning the risk factors of MRSA and VRSA infections. RESULTS: Nasal swab results obtained as many as 30 (23.5%) MRSA positive subjects and 6 (4.7%) subjects with positive VRSA. The most common risk factors that led to MRSA colonization included a history of positive MRSA in the previous hospital (60%), a history of ear, nose, and throat infection (41.7%), and did not do hand rub/handwash (36.7%). In comparison, the most risk factors for VRSA colonization were having pigs farm at home (33.3%), a history of positive MRSA in the previous hospital (20%), and a history of hospitalization in the past 6–12 months (16.7%). The results of multivariate analysis showed the most powerful and statistically significant risk factors in influencing nasal MRSA colonization were a history of positive MRSA in the previous hospital (OR 13.69, 95% confidence intervals [CI]: 1.34–140.25, p = 0.028) and did not do hand rub/handwash (OR 2.95, 95% CI: 1.167–7.49, p = 0.023). Meanwhile, marital status (OR 0.160, 95% CI: 0.02–1.06), p = 0.058) and home care service (OR 6.10, 95% CI: 0.79–46.96, p = 0.082) were the strongest risk factors for nasal colonization of VRSA but not statistically significant. CONCLUSION: As many as, 23.5% and 4.7% of healthcare workers’ subjects were found with nasal colonization of MRSA and VRSA, respectively. Accordingly, strict policies are needed to minimize the transmission of these organisms from the hospital setting to the community.

Nosocomial pneumonia with multi-resistant bacteria in the intensive care units

A nosocomial pneumonia is a pulmonary infection occurring in a patient after 48 hours of care in a health care facility, it is an infection that is serious because it is often due to multi-resistant germs called multi-resistant bacteria. The objective of our study is to analyze the bacterial ecology of nosocomial pneumopathies in intensive care units and their evolution between January 1st 2021 and December 31st 2021. We conducted a monocentric retrospective study in the microbiology laboratory of the CHU HASSAN II of Fez. We analyzed all the respiratory microbiological diagnostic samples taken during this period (identified germ, sensitivity profile), and collected the demographic characteristics of the associated population. Out of 192 respiratory samples received, 106 were multidrug resistant bacteria (52.6%). The proportions of the different bacterial classes (BGN / CG+) have remained stable over the last 4 years with a predominance of Acinetobacter baumanii with 93%, followed by Klebsiella pneumoniae (4.7%) and Escherichia coli (2.83%)..Bacteria of clinical interest showed increasingly worrying levels of resistance to beta-lactam antibiotics, with the exception of methicillin-resistant Staphylococcus aureus, which remained stable between 2018 and 2021.This work is part of a process of improving antibiotic prescribing practices and analyzing the impact of changes in antibiotic therapy protocols on the ecology of the service.

Half sandwich-type osmium, ruthenium, iridium and rhodium complexes with bidentate glycosyl heterocyclic ligands induce cytostasis in platinum-resistant ovarian cancer cells and bacteriostasis in Gram-positive multiresistant bacteria.

The toxicity of and resistance to platinum complexes as cisplatin, oxaliplatin or carboplatin calls for the replacement of these therapeutic agents in clinical settings. We have previously identified a set of half sandwich-type osmium, ruthenium and iridium complexes with bidentate glycosyl heterocyclic ligands exerting specific cytostatic activity on cancer cells but not on non-transformed primary cells. The apolar nature of the complexes, conferred by large, apolar benzoyl protective groups on the hydroxyl groups of the carbohydrate moiety, was the main molecular feature to induce cytostasis. We exchanged the benzoyl protective groups to straight chain alkanoyl groups with varying length (3 to 7 carbon units) that increased the IC50 value as compared to the benzoyl-protected complexes and rendered the complexes toxic. These results suggest a need for aromatic groups in the molecule. The pyridine moiety of the bidentate ligand was exchanged for a quinoline group to enlarge the apolar surface of the molecule. This modification decreased the IC50 value of the complexes. The complexes containing [(η6-p-cymene)Ru(II)], [(η6-p-cymene)Os(II)] or [(η5-Cp*)Ir(III)] were biologically active unlike the complex containing [(η5-Cp*)Rh(III)]. The complexes with cytostatic activity were active on ovarian cancer (A2780, ID8), pancreatic adenocarcinoma (Capan2), sarcoma (Saos) and lymphoma cell lines (L428), but not on primary dermal fibroblasts and their activity was dependent on reactive oxygen species production. Importantly, these complexes were cytostatic on cisplatin-resistant A2780 ovarian cancer cells with similar IC50 values as on cisplatin-sensitive A2780 cells. In addition, the quinoline-containing Ru and Os complexes and the short chain alkanoyl-modified complexes (C3 and C4) proved to be bacteriostatic in multiresistant Gram-positive Enterococcus and Staphylococcus aureus isolates. Hereby, we identified a set of complexes with submicromolar to low micromolar inhibitory constants against a wide range of cancer cells, including platinum resistant cells and against multiresistant Gram-positive bacteria.