Development Of Antimicrobial Resistance Research Articles

Bioselective and Radiopaque Zinc-Biopolymeric Complex-Based Porous Biomaterials Promote Mammalian Tissue Ingrowth In Vivo While Inhibiting Microbial Biofilm Gene Expression and Biofilm Formation.

Metal-organic complexes have shown astounding bioactive properties; however, they are rarely explored as biomaterials. Recent studies showed that carboxymethyl-chitosan (CMC) genipin-conjugated zinc biomimetic scaffolds have unique bioselective properties. The biomaterial was reported to be mammalian cell-friendly; at the same time, it was found to discourage microbial biofilm formation on its surface, which seemed to be a promising solution to addressing the problem of trauma-associated biofilm formation and development of antimicrobial resistance. However, the mechanically frail characteristics and zinc overload raise concerns and limit the potential of the said biomaterials. Hence, the present work is focused on improving the strength of the earlier scaffold formulations, testing its in vivo efficacy and reaffirming its action against biofilm-forming microbe Staphylococcus aureus. Scaling up of CMC proportion increased rigidity, and 8% CMC was found to be the ideal concentration for robust scaffold fabrication. Freeze-dried CMC scaffolds with or without genipin (GP) cross-linking were conjugated with zinc using 2 M zinc acetate solution. Characterization results indicated that the CMC-Zn scaffolds, without genipin, showed mechanical properties close to bone fillers, resist in vitro enzymatic degradation until 4 weeks, are porous in nature, and have radiopacity close to mandibular bones. Upon implantation in a subcutaneous pocket of Wistar rats, the scaffolds showed tissue in-growth with simultaneous degradation without any signs of toxicity past 28 days. Neither were there any signs of toxicity in any of the vital organs. Considering many superior properties among the other formulations, the CMC-Zn scaffolds were furthered for biofilm studies. CMC-Zn showed negligible S. aureus biofilm formation on its surface as revealed by an alamar blue-based study. RT-PCR analysis revealed that CMC-Zn downregulated the expression of pro-biofilm effector genes such as icaC and clfB. A protein docking study predicted the inhibitory mechanism of CMC-Zn. Although it binds strongly when alone, at high density, it may cause inactivation of the transmembrane upstream activators of the said genes, thereby preventing their dimerization and subsequent inactivation of the effector genes. In conclusion, zinc-conjugated carboxymethyl-chitosan scaffolds are mechanically robust, porous, yet biodegradable, harmless to the host in the long term, they are radiopaque and prevent biofilm gene expression in notorious microbes; hence, they could be a suitable candidate for bone filler applications.

Inferring diet, disease and antibiotic resistance from ancient human oral microbiomes.

The interaction between a host and its microbiome is an area of intense study. For the human host, it is known that the various body-site-associated microbiomes impact heavily on health and disease states. For instance, the oral microbiome is a source of various pathogens and potential antibiotic resistance gene pools. The effect of historical changes to the human host and environment to the associated microbiome, however, has been less well explored. In this review, we characterize several historical and prehistoric events which are considered to have impacted the oral environment and therefore the bacterial communities residing within it. The link between evolutionary changes to the oral microbiota and the significant societal and behavioural changes occurring during the pre-Neolithic, Agricultural Revolution, Industrial Revolution and Antibiotic Era is outlined. While previous studies suggest the functional profile of these communities may have shifted over the centuries, there is currently a gap in knowledge that needs to be filled. Biomolecular archaeological evidence of innate antimicrobial resistance within the oral microbiome shows an increase in the abundance of antimicrobial resistance genes since the advent and widespread use of antibiotics in the modern era. Nevertheless, a lack of research into the prevalence and evolution of antimicrobial resistance within the oral microbiome throughout history hinders our ability to combat antimicrobial resistance in the modern era.

Left knee septic monoarthritis in a pediatric patient due to shewanella putrefaciens: case report and literature review

BackgroundShewanella putrefaciens is a gram-negative, nonfermenting, oxidase-positive, hydrogen sulfide-producing bacillus and a halophilic bacterium, known for causing unusual infections in humans and often regarded as an opportunistic pathogen. Its diverse symptoms have a significant impact on human health, with 260 documented disorders reported in the literature over the last 40 years, highlighting its potential danger.Case presentationWe present the case of a previously healthy 15-year-old male patient who sustained a self-inflicted sharp-object injury while working in the field, resulting in secondary septic monoarthritis due to Shewanella putrefaciens.ConclusionsThis case highlights the bacteriological and clinical characteristics, as well as the antibiogram, of Shewanella spp. Given the recent increase in notifications of Shewanella infections, predominantly by S. algae and S. putrefaciens, it is essential to consider these pathogens in patients with a history of contact with bodies of water. Special attention must be paid to their resistance patterns in patient management to prevent the development of intrinsic antimicrobial resistance.

Investigating the feasibility and potential of combining industry AMR monitoring systems: a comparison with WHO GLASS

Background Efforts to estimate the global burden of antimicrobial resistance (AMR) have highlighted gaps in existing surveillance systems. Data gathered from hospital networks globally by pharmaceutical industries to monitor antibiotic efficacy in different bacteria represent an additional source to track the temporal evolution of AMR. Here, we analysed available industry monitoring systems to assess to which extent combining them could help fill the gaps in our current understanding of AMR levels and trends. Methods We analysed six industry monitoring systems (ATLAS, GEARS, SIDERO-WT, KEYSTONE, DREAM, and SOAR) obtained from the Vivli platform and reviewed their respective isolates collection and analysis protocols. Using the R software, we designed a pipeline to harmonise and combine these into a single dataset. We assessed the reliability of resistance estimates from these sources by comparing the combined dataset to the publicly available subset of WHO GLASS for shared bacteria-antibiotic-country-year combinations. Results Combined, the industry monitoring systems cover 18 years (4 years for GLASS), 85 countries (71), 412 bacterial species (8), and 75 antibiotics (25). Although all industry systems followed a similar centralised testing approach, the criteria for isolate collection were unclear (patients selection, associated sampling periods…). For E.coli, K. pneumoniae and S. aureus, at least 65% of comparable resistance proportions were within 0.1 of the corresponding estimate in GLASS. We did not identify systemic bias towards resistance in industry systems compared to GLASS. Conclusions Combining industry monitoring systems can substantially strengthen our knowledge of global AMR burden across bacterial species and countries. High agreement values for available comparisons with GLASS suggest that data for other bacteria-antibiotic-country-year combinations only present in industry systems could complement GLASS, particularly for Priority Pathogens currently not covered. This valuable information on resistance levels could help clinicians and stakeholders prioritize testing and select appropriate antibiotics in settings with limited surveillance data.

Taurolidine and Heparin as Catheter Lock Solution for Central Venous Catheters in Hemodialysis.

Chronic kidney disease can lead to end-stage renal disease, and the prevalence is increasing. Many patients starting hemodialysis require central venous catheters (CVCs). Catheter-related bloodstream infections (CRBSIs) are a common complication and lead to significant morbidity and mortality. Interventions to prevent CRBSI include antimicrobial lock therapy but concern for the development of antimicrobial resistance and adverse effects. Nonantimicrobial antiseptics as catheter lock solutions have also been used. Taurolidine and heparin catheter lock solution is first approved by the Food and Drug Administration for the prevention of CRBSI in patients on hemodialysis. Taurolidine has a unique mechanism of action and favorable safety profile. Taurolidine and heparin catheter lock solution have both antimicrobial and anticoagulant properties. Taurolidine is derivative of the amino acid taurine, and heparin is derived from porcine intestinal mucosa. Taurolidine not only damages microbial cell walls but also prevents the adherence of microorganisms to biological surfaces, preventing biofilm formation. Taurolidine and heparin catheter lock solution is intended to be used intraluminally within the catheter and should be aspirated. Because it is used locally, limited pharmacokinetic and pharmacodynamic data are available. The LOCK-IT-100 trial is a randomized, double-blind, phase 3 study, which included 795 end-stage renal disease patients on hemodialysis with CVC. Taurolidine and heparin was compared with the control heparin alone. The results of the study showed a 71% risk reduction in CRBSI for taurolidine and heparin arm (95% confident interval, 38%-86%, P = 0.0006). Other studies have also shown that taurolidine lock solution leads to decreased CRBSI episodes. Several systematic reviews and meta-analysis consisted of taurolidine in adult, and pediatric populations also showed reduction in the incidence of CRBSIs. Taurolidine and heparin lock solution represents a novel preventive strategy for those undergoing hemodialysis through a CVC by reducing the risk of CRBSI. This is significant progress because there are no other similar options available for patients for whom catheters are the only options for their life-saving treatment.

Hungarian general practice paediatricians’ antibiotic prescribing behaviour for suspected respiratory tract infections: a qualitative study

ObjectivesInappropriate antibiotic prescribing is a major cause of antimicrobial resistance (AMR). The aim of this study was to explore paediatric general practitioners’ (GP Peds) antibiotic prescription practice in suspected respiratory...

Composting manure in the poultry farm harbours multidrug-resistance Salmonella

ABSTRACT Salmonella is one of the leading foodborne pathogens that cause gastroenteritis. It is imperative to monitor Salmonella contamination within poultry farms. This study focuses on the prevalence of Salmonella in composting manure at poultry farms a potential and persistent contamination sources. A batch of manure samples (n = 10) were collected from a local poultry farm, and half of the manure samples were detected to be Salmonella-positive. Serotyping results showed four serotypes among different isolated strains, including Typhimurium, Typhi, Newport, and Dublin. Isolates from manure generally demonstrated a high ciprofloxacin resistance and biofilm formation capacity. Multi-drug resistance was found in isolates from organic manure that had been fermented using high-temperature aerobic technology. Our study indicated that composting manure harboured Salmonella and might facilitate the transmission of Salmonella and the development of antimicrobial resistance. Proper composting strategies are needed to reduce the transmission of antimicrobial resistance and Salmonella.

When Antimicrobial Treatment and Surgical Prophylaxis Collide: A Stewardship Opportunity

Background: In 2002, the Centers for Medicare and Medicaid Services (CMS) in collaboration with the Centers for Disease Control and Prevention (CDC) established the Surgical Infection Prevention (SIP) project for the purposes of developing and standardizing quality improvement measures known to reduce the rates of post-operative surgical site infections (SSIs). Four years later the Surgical Care Improvement Project (SCIP), an expansion of SIP, was published in governmental Specifications Manual for National Inpatient Quality Measures and provided several additional initiatives applicable to the perioperative period. Central to both projects are the assurance of the timeliness, selection, and duration of peri-operative surgical prophylactic antibiotics. In support of this objective, various medical associations, such as the American Society of Health-System Pharmacists (ASHP) and the Infectious Diseases Society of America (IDSA), have developed the Clinical Practice Guidelines for Antimicrobial Prophylaxis in Surgery. To ensure compliance with quality measures, hospitals are required to report data to the Physicians Quality Reporting System, which is then reviewed by CMS for reimbursement purposes and to measure hospital performance. To maintain optimal standards of care and satisfy all core measures, it is expected that patients undergoing most categories of surgical procedures receive prophylactic antibiotics. We recognized that patients already being administered antimicrobial therapy as treatment for the condition requiring the surgery not uncommonly also were prescribed unwarranted and redundant pre-operative antibiotics. Our study was meant to quantify such antibiotic redundancy, which only risks the development of antimicrobial resistance and adverse events, to bolster our and other hospitals antimicrobial stewardship programs. Methods: A retrospective analysis of computerized hospital records over a one-month period of time (November 2022) was conducted focusing on hospital admissions that involved surgical operative procedures. Only those patients who had received a pre-operative surgical prophylactic antibiotic were included in the analysis. Results: Of the 92 surgeries that fulfilled the inclusion criteria, 38 (41.3%) were performed on patients who were already receiving therapeutic antibiotics for more than 24 hours targeted to treat the infection for which they were undergoing surgery. These included laparoscopic cholecystectomy (24), appendectomy (12), wound debridement (12), and soft tissue incision and drainage procedures (9), comprising nearly 50% of each type of these operations performed during the study time period. Conclusion: These findings demonstrate a clear opportunity to strengthen both our, and presumably other, hospitals antimicrobial stewardship programs. Together with physician education, granting the pharmacy the ability to cancel unnecessary and redundant surgical prophylactic antibiotics would conceivably be of great benefit.

Ultra-sensitive electrochemical detection of levofloxacin using a binder-free copper and graphene composite

Given the levels of pollution in the aquatic environment and the development of antimicrobial resistance, it is essential to develop sensors, with sensitivity, selectivity, stability, and cost-effectiveness, for the determination of antibiotics. The present article highlights the fabrication of an ultra-sensitive graphene and copper sensor, Gr/Cu, supported on glassy carbon (GCE/Gr/Cu) for the electroanalysis of levofloxacin through a cost-effective electrodeposition method. The sequential electrodeposition of graphene and Cu was optimised to give GCE/Gr/Cu, with the Cu particles well dispersed on the graphene sheets. The composite exhibited very good conducting properties as evidenced from electrochemical impedance studies. Using cyclic voltammetry, an impressive sensitivity of 19.7 μA μM−1 cm−2 was achieved with a detection limit of 11.86 nM, providing a promising electrocatalytic material for the determination of this antibiotic. Moreover, good selectivity was observed in the presence of various ions typically found in water and other drug molecules, while very good stability exceeding a 21-day period was achieved, and recovery values between 97.7 and 103.8 % were obtained in tap water.

Novel in-genome based analysis demonstrates the evolution of OmpK37, antimicrobial resistance gene from a potentially pathogenic pandrug resistant Klebsiella pneumoniae MS1 isolated from healthy broiler feces

Antimicrobial resistance transmission from farm animals to humans is a critical health concern and hence a detailed molecular surveillance is essential for tracking the spread and consequent evolution of antimicrobial resistance. In this study, a pan-drug resistant Klebsiella pneumoniae MS1 strain was isolated from a healthy broiler farm and studied. From the results of the study, MS1 was found to be is resistant to 18 tested antibiotics and has a high-risk to be pathogenic to humans with a probability of 0.80. The whole genome sequencing data of MS1 was used to predict the presence of antimicrobial resistance genes and pathogenicity. The genome analysis has revealed MS1 to have 34 AMR genes. Out of these, the AMR gene OmpK37 codes for an important protein involved in cell permeability and hence in antibiotic resistance. Further analysis was carried out by using an in-genome analysis method to understand the evolution of OmpK37 and the underlying reason for the emergence of resistance. From the detailed analysis, the current study could demonstrate for the first time the evolution of OmpK37 from OmpC. Though structurally OmpK37 was very similar to other porins present in MS1, it was found to have higher mutability as a distinguishing feature which makes it an important protein in monitoring the evolving resistances in microorganisms.

Heavy Metals as Catalysts in the Evolution of Antimicrobial Resistance and the Mechanisms Underpinning Co-selection.

The menace caused by antibiotic resistance in bacteria is acknowledged on a global scale. Concerns over the same are increasing because of the selection pressure exerted by a huge number of different antimicrobial agents, including heavy metals. Heavy metals are non-metabolizable and recalcitrant to degradation, therefore the bacteria can expel the pollutants out of the system and make it less harmful via different mechanisms. The selection of antibiotic-resistant bacteria may be influenced by heavy metals present in environmental reservoirs. Through co-resistance and cross-resistance processes, the presence of heavy metals in the environment can act as co-selecting agents, hence increasing resistance to both heavy metals and antibiotics. The horizontal gene transfer or mutation assists in the selection of mutant bacteria resistant to the polluted environment. Hence, bioremediation and biodegradation are sustainable methods for the natural clean-up of pollutants. This review sheds light on the occurrence of metal and antibiotic resistance in the environment via the co-resistance and cross-resistance mechanisms underpinning co-selection emphasizing the dearth of studies that specifically examine the method of co-selection in clinical settings. Furthermore, it is advised that future research incorporate both culture- and molecular-based methodologies to further our comprehension of the mechanisms underlying bacterial co- and cross-resistance to antibiotics and heavy metals.

Trends of Antimicrobial Susceptibility of Neisseria gonorrhoeae isolates between 2012 and 2023: results from an open Italian cohort.

Neisseria gonorrhoeae (Ng) is a public health priority due to the rapid evolution of antimicrobial resistance, the emergence of antibiotic resistance and the absence of a vaccine against Ng. The aim of this study was to investigate trends in the minimum inhibitory concentration (MIC) and resistance (R) or reduced susceptibility (DS) of Ng cases to ceftriaxone (CRO), azithromycin (AZM), tetracycline (TET), benzylpenicillin (PenG), ciprofloxacin (CIP) over a 10-year period. Retrospective analysis on an open cohort of Ng cases diagnosed on rectal, urethral and pharyngeal samples at San Raffaele Scientific Institute, between September 2012-February 2023. MICs of antibiotics were determined by gradient-test strips. Bivariate linear regression models, applied on logarithmic MICs values; Cochran-Armitage test was used to determine a linear trend in the proportions of resistant strains. 436 Ng isolates from 352 individuals were analyzed. MICs of CRO and PenG reduced over time (p < 0.001, p = 0.030), AZM increased (p = 0.001), CIP and TET did not change (p = 0.473, p = 0.272). The percentages of resistant strains were: PenG 89.9%, TET 90.8%, CIP 48.2%, AZM 4.4%; CRO-DS strains were 8.7%, only one CRO-R. The proportion of resistant strains increased over time for AZM (p = 0.007), TET (p = 0.001), CIP (p < 0.001), whereas decreased for PenG (p < 0.001) and CRO-DS/R strains (p < 0.001). Ng strains showed high susceptibility to CRO, although we identified cases of DS/R and observed high levels of susceptibility to AZM. Overall, the recommended primary regimen for Ng treatment confirmed to be effective.

Multiblock partial least squares and rank aggregation: Applications to detection of bacteriophages associated with antimicrobial resistance in the presence of potential confounding factors.

Urban environments, characterized by bustling mass transit systems and high population density, host a complex web of microorganisms that impact microbial interactions. These urban microbiomes, influenced by diverse demographics and constant human movement, are vital for understanding microbial dynamics. We explore urban metagenomics, utilizing an extensive dataset from the Metagenomics & Metadesign of Subways & Urban Biomes (MetaSUB) consortium, and investigate antimicrobial resistance (AMR) patterns. In this pioneering research, we delve into the role of bacteriophages, or "phages"-viruses that prey on bacteria and can facilitate the exchange of antibiotic resistance genes (ARGs) through mechanisms like horizontal gene transfer (HGT). Despite their potential significance, existing literature lacks a consensus on their significance in ARG dissemination. We argue that they are an important consideration. We uncover that environmental variables, such as those on climate, demographics, and landscape, can obscure phage-resistome relationships. We adjust for these potential confounders and clarify these relationships across specific and overall antibiotic classes with precision, identifying several key phages. Leveraging machine learning tools and validating findings through clinical literature, we uncover novel associations, adding valuable insights to our comprehension of AMR development.

Understanding Vietnamese chicken farmers' knowledge and practices related to antimicrobial resistance using an item response theory approach.

Antimicrobial resistance (AMR) poses a threat to animal and human health, as well as food security and nutrition. Development of AMR is accelerated by over- and misuse of antimicrobials as seen in many livestock systems, including poultry production. In Vietnam, high AMR levels have been reported previously within poultry production, a sector which is dominated by small-scale farming, even though it is intensifying. This study focuses on understanding small- and medium-scale chicken farmers' knowledge and practices related to AMR by applying an item response theory (IRT) approach, which has several advantages over simpler statistical methods. Farmers representing 305 farms in Thai Nguyen province were interviewed from November 2021 to January 2022, using a structured questionnaire. Results generated with IRT were used in regression models to find associations between farm characteristics, and knowledge and practice levels. Descriptive results showed that almost all farmers could buy veterinary drugs without prescription in the local community, that only one third of the farmers received veterinary professional advice or services, and that the majority of farmers gave antibiotics as a disease preventive measure. Regression analysis showed that multiple farm characteristics were significantly associated to farmers' knowledge and practice scores. The study highlights the complexity when tailoring interventions to move towards more medically rational antibiotic use at farms in a setting with high access to over-the-counter veterinary drugs and low access to veterinary services, since many on-farm factors relevant for the specific context need to be considered.

Specific and Nonspecific Effects of Influenza Vaccines.

With the introduction of the influenza vaccine in the official immunization schedule of most countries, several data regarding the efficacy, tolerability, and safety of influenza immunization were collected worldwide. Interestingly, together with the confirmation that influenza vaccines are effective in reducing the incidence of influenza virus infection and the incidence and severity of influenza disease, epidemiological data have indicated that influenza immunization could be useful for controlling antimicrobial resistance (AMR) development. Knowledge of the reliability of these findings seems essential for precise quantification of the clinical relevance of influenza immunization. If definitively confirmed, these findings can have a relevant impact on influenza vaccine development and use. Moreover, they can be used to convince even the most recalcitrant health authorities of the need to extend influenza immunization to the entire population. In this narrative review, present knowledge regarding these particular aspects of influenza immunization is discussed. Literature analysis showed that the specific effects of influenza immunization are great enough per se to recommend systematic annual immunization of younger children, old people, and all individuals with severe chronic underlying diseases. Moreover, influenza immunization can significantly contribute to limiting the emergence of antimicrobial resistance. The problem of the possible nonspecific effects of influenza vaccines remains unsolved. The definition of their role as inducers of trained immunity seems essential not only to evaluate how much they play a role in the prevention of infectious diseases but also to evaluate whether they can be used to prevent and treat clinical conditions in which chronic inflammation and autoimmunity play a fundamental pathogenetic role.

Prevalence of Extended-Spectrum β-Lactamases (ESBLs) Producing Aeromonas spp. Isolated from Lamellidens marginalis (Lamark, 1819) of Sewage-Fed Wetland: A Phenotypic and Genotypic Approach.

The global rise of zoonotic bacteria resistant to multiple antimicrobial classes and the growing occurrence of infections caused by Aeromonas spp. resistant to β-lactam antibiotics pose a severe threat to animal and human health. However, the contribution of natural environments, particularly aquatic ecosystems, as ideal settings for the development and spread of antimicrobial resistance (AMR) is a key concern. Investigating the phenotypic antibiotic resistance and detection of β-lactamase producing Aeromonas spp. in Lamellidens marginalis, which inhabit all freshwater ecosystems of the Indian subcontinent, is essential for implications in monitoring food safety and drug resistance. In the present investigation, 92 isolates of Aeromonas spp. were recovered from 105 bivalves and screened for their antimicrobial resistance patterns. In vitro antibiotic resistance profiling showed a higher Multiple Antibiotic Resistance (MAR) index of 0.8 with the highest resistance against ampicillin/sulbactam (82%), while 58, 44, 39 and 38% of the isolates were resistant to cephalothin, erythromycin, cefoxitin and imipenem, respectively. PCR results revealed that these isolates carried the blaTEM gene (94%), which was followed by the blaCTX-M gene (51%) and the blaSHV gene (45%). A combination of blaSHV, blaCTX-M, and blaTEM genes was found in 17% of the isolates, indicating the presence of all three resistance genes. This is the first investigation which highlights the importance of multidrug-resistant Aeromonas spp. in L. marginalis. The identification of extended-spectrum-β-lactamases (ESBLs) genes demand the necessity of continuous surveillance and systematic monitoring, considering its potential health risks for both animals and human beings.

IJCM_238A: Level of awareness regarding antimicrobial resistance among residents in a hilly area of Uttarakhand: A cross sectional study

Background: Antimicrobial resistance (AMR) poses a global threat to public health, it demands a comprehensive understanding and awareness among people. With overuse and misuse of antibiotics, there is increasing need to assess knowledge levels within community to formulate effective interventions. This study aims to detect this knowledge gap and contribute to the efforts in combating AMR. Objectives: 1. To assess the level of awareness among residents of study area regarding antibiotics, their appropriate use and concept of AMR. 2. To pinpoint specific areas of misunderstanding or misinformation regarding AMR. Methodology: A community based cross-sectional study was conducted among community members in hilly region of Uttarakhand in October and November 2023. Simple random sampling technique was used to select respondents. A predesigned semi-structured questionnaire was used to interview the respondents by home visits. Data was analyzed using SPSS version 20. Results: Mean age of respondents is 33.35 ±13.8 in years, 44.7% of the respondents believed that sometimes to save time, they can purchase antibiotics from pharmacist without asking a doctor. 37.8% respondents believe that they can share antibiotics with friends or relatives for similar symptoms. There is a clear pattern in terms of age, respondents between 18-34 years of age are more aware regarding AMR as compared to higher age groups. Conclusion: More than half of the respondents are unaware regarding antimicrobial resistance and the specific areas of misunderstanding among respondents are that length of antibiotic course and poor sanitation and hygiene determines development of AMR.

Perspective of Secondary Metabolites in Respect of Multidrug Resistance (MDR): A Review.

Aberrant and haphazard use of antibiotics has created the development of antimicrobial resistance which is a bizarre challenge for human civilization. This emerging crisis of antibiotic resistance for microbial pathogens is alarming all the nations posing a global threat to human health. It is difficult to treat bacterial infections as they develop resistance to all antimicrobial resistance. Currently used antibacterial agents inhibit a variety of essential metabolic pathways in bacteria, including macro-molecular synthesis (MMS) pathways (e.g. protein, DNA, RNA, cell wall) most often by targeting a specific enzyme or subcellular component e.g. DNA gyrase, RNA polymerase, ribosomes, transpeptidase. Despite the availability of diverse synthetic molecules, there are still many complications in managing progressive and severe antimicrobial resistance. Currently not even a single antimicrobial agent is available for which the microbes do not show resistance. Thus, the lack of efficient drug molecules for combating microbial resistance requires continuous research efforts to overcome the problem of multidrug-resistant bacteria. The phytochemicals from various plants have the potential to combat the microbial resistance produced by bacteria, fungi, protozoa and viruses without producing any side effects. This review is a concerted effort to identify some of the major active phytoconstituents from various medicinal plants which might have the potential to be used as an alternative and effective strategy to fight against microbial resistance and can promote research for the treatment of MDR.

Predicting Antibiotic Resistance and Assessing the Risk Burden from Antibiotics: A Holistic Modeling Framework in a Tropical Reservoir.

Predicting the hotspots of antimicrobial resistance (AMR) in aquatics is crucial for managing associated risks. We developed an integrated modeling framework toward predicting the spatiotemporal abundance of antibiotics, indicator bacteria, and their corresponding antibiotic-resistant bacteria (ARB), as well as assessing the potential AMR risks to the aquatic ecosystem in a tropical reservoir. Our focus was on two antibiotics, sulfamethoxazole (SMX) and trimethoprim (TMP), and on Escherichia coli (E. coli) and its variant resistant to sulfamethoxazole-trimethoprim (EC_SXT). We validated the predictive model using withheld data, with all Nash-Sutcliffe efficiency (NSE) values above 0.79, absolute relative difference (ARD) less than 25%, and coefficient of determination (R2) greater than 0.800 for the modeled targets. Predictions indicated concentrations of 1-15 ng/L for SMX, 0.5-5 ng/L for TMP, and 0 to 5 (log10 MPN/100 mL) for E. coli and -1.1 to 3.5 (log10 CFU/100 mL) for EC_SXT. Risk assessment suggested that the predicted TMP could pose a higher risk of AMR development than SMX, but SMX could possess a higher ecological risk. The study lays down a hybrid modeling framework for integrating a statistic model with a process-based model to predict AMR in a holistic manner, thus facilitating the development of a better risk management framework.

Retrospective Analysis of Antimicrobial Susceptibility Pattern of Pseudomonas aeruginosa from Clinical Samples of Dogs in Grenada, West Indies

Background: Clinical infections caused by multidrug-resistant pathogenic bacteria are associated with increased morbidity and mortality, imposing a severe economic burden. Pseudomonas aeruginosa, a gram-negative bacterium, had demonstrated a prominent level of acquired antimicrobial resistance to its selective antimicrobials. Currently, there is no updated information about the antimicrobial susceptibility pattern of Pseudomonas aeruginosa in Grenada. Hence, the present study aimed to determine the antimicrobial susceptibility pattern of P. aeruginosa from the clinical isolates of dogs in Grenada. Methods: This retrospective study used the diagnostic reports from January 2015 to December 2022. The diagnostic microbiology laboratory reports of canine patients at the Small Animal Clinic of St. George’s University in Grenada were analyzed to study the antimicrobial susceptibility pattern of P. aeruginosa. Result: Among the various bacterial clinical isolates, ninety-one clinical samples were positive for P. aeruginosa. The antimicrobial susceptibility test pattern of these isolates revealed susceptibility to gentamicin (95.6 %), ceftazidime (96.7%), imipenem (97.7%) and ciprofloxacin (97.8%). The result of the present retrospective study illustrates that P. aeruginosa isolates from canine patients in Grenada are susceptible to the recommended antimicrobial drugs. However, this study also revealed the recent development of progressive antimicrobial resistance. This mandates the judicious use of antibacterial drugs against bacterial infections in Grenada.