Journal of Global Antimicrobial Resistance

Biofilms pose a significant challenge to antimicrobial therapy. Bacteria in biofilms differ from planktonic counterpart in their altered metabolism, collective behavior, protective role of extracellular matrix and diversified microbial subpopulations. These attributions significantly influence bioavailability and activity of antibiotics. The presence of bacterial aggregates during acute infections expands the problem to many other conditions previously not discussed in the biofilm context. Klebsiella pneumoniae is a leading cause of life-threatening hospital-acquired infections and is included in the WHO Bacterial Priority Pathogens List due to increasing antimicrobial resistance. The combination of antimicrobial resistance and the ability to form biofilms severely limits the efficacy of antibiotic treatments. In this study, we investigated the in vitro susceptibility of mature biofilms to 13 antimicrobials of K. pneumoniae clinical isolates from a single hospital. The resistance profiles of the local clinical isolates were consistent with the global epidemiology of K. pneumoniae. Minimal biofilm eradication concentrations (MBEC) for mature biofilms were defined with two assays (biomass and metabolic activity measurements) and brought into relation with susceptibility breakpoints and plasma (Cmax). Colistin sulfate, tigecycline, cephalosporins and combination of imipenem with cilastatin were the most potent biomass eradicators, while suppression of metabolic activity was barely reachable. Moreover, we observed a notable increase in metabolic activity upon exposure to sub-MBEC concentrations of antibiotics. Finally, our data broach a subject of antibiotic prioritization with respect to biofilm tolerance. IMPORTANCEThis study addresses the critical gap between standard antibiotic susceptibility testing and the tolerance of biofilm and microbial aggregates during infections caused by K. pneumoniae. By systematically evaluating mature biofilms from a significant number of clinical isolates, we demonstrate that colistin and tigecycline show potent activity against both biofilm biomass and metabolic activity, whereas cephalosporins primarily reduce biomass without effectively suppressing bacterial metabolism, and other drugs have only weak effects on biofilms at clinically achievable concentrations. Furthermore, the alarming observation that sub-inhibitory biofilm eradication concentration (sub-MBEC) of antibiotic can paradoxically increase the metabolic activity of biofilms highlights a potential risk factor for therapy failure and resistance development. Our findings contribute to the necessary evidence base for prioritizing existing antibiotics in the limited armamentarium against biofilm-forming K. pneumoniae.

AimsPseudomonas aeruginosa biofilm-associated infections pose a significant clinical challenge due to their inherent antibiotic tolerance. This study aimed to evaluate the antibacterial and antibiofilm activity of Placentrex, a standardised aqueous placental extract, against P. aeruginosa and to elucidate its molecular mechanism of action using RNA sequencing (RNA-seq). Methods and ResultsPlacentrex exhibited potent bactericidal activity against P. aeruginosa at 50 mg/mL. Biofilm formation was significantly inhibited by [~]87% at 50mg/mL after 72 hours. Preformed biofilms were eradicated by [~]93% and [~]89% at 50 and 25 mg/mL, respectively. Interestingly, biofilm viability was reduced by [~]93% and [~]87% upon treatment with 50 mg/mL and 25 mg/mL of Placentrex, respectively. EPS characterisation revealed that the EPS contain a single large polysaccharide, and chromatography data suggested that it is made up of glucose as a monomer. RNA-seq identified coordinated downregulation of seven key genes, namely, flp major pilin (surface attachment), extracellular solute binding protein (ABC transporter-mediated nutrient sensing and biofilm maintenance), gntP permease (carbon metabolism), AraC family transcriptional regulator (quorum sensing and polysaccharide biosynthesis), ureE (urease nickel metallochaperone), aromatic amino acid permease (pyoverdine and PQS biosynthesis), and MFS transporter (efflux and autoinducer export). ConclusionsPlacentrex exerts comprehensive antibiofilm and antibacterial activity through simultaneous disruption of surface attachment, nutrient-sensing-driven biofilm maintenance, quorum sensing, carbon metabolism, urease virulence maturation, and efflux-mediated persistence. This polypharmacological mechanism supports Placentrex as a promising multi-target antibacterial agent against P. aeruginosa biofilm-associated infections. Impact statementPlacentrex is a potential anti-biofilm agent against Pseudomonas aeruginosa.

ABSTRACT Background: Self medication with analgesics and non steroidal anti inflammatory drugs (NSAIDs) is common in low- and middle income countries and may expose users to preventable adverse outcomes. Evidence from Guinea remains scarce. This study aimed to estimate the prevalence of self medication with analgesics and NSAIDs among pharmacy clients in urban Conakry, identify associated factors, and describe clinical risk situations. Methods: We conducted a pharmacy based analytical cross sectional study in 30 private pharmacies across Conakry, Guinea. A total of 1,032 participants seeking analgesics or NSAIDs were enrolled between November 3, 2012, and April 5, 2013. Self-medication was defined as acquisition or use without a valid medical prescription. Factors associated with self-medication were analysed using multivariable logistic regression. Results: Among 1,032 participants, 603 reported self medication (prevalence 58.4%). Previous unsupervised use was reported by 78.7%. The most frequently used medicines were paracetamol (56.9%, n=587), diclofenac (21.3%, n=220), ibuprofen (17.9%, n=185), and aspirin (3.9%, n=40). Overall, 68.0% (n=702) reported no knowledge of potential adverse effects. Clinical risk situations were frequent: gastrointestinal disorders (41.3%, n=426), hypertension (9.2%, n=95), and pregnancy exposure among reproductive age women (26.0%). In multivariable analysis, self medication was independently associated with previous analgesic/NSAID use (aOR = 2.8, 95% CI: 2.1 to 3.6), lack of knowledge of adverse effects (aOR = 1.9, 95% CI: 1.4 to 2.5), informal occupation (aOR = 1.6, 95% CI: 1.2 to 2.2), and age 18 to 59 years (aOR = 1.5, 95% CI: 1.1 to 2.1). Conclusions: In this pharmacy based study conducted in urban Conakry, self medication with analgesics and NSAIDs was common and frequently associated with limited awareness of potential adverse effects. These findings support the need for strengthened pharmaceutical regulation, pharmacist-led counselling, health literacy interventions, and improved access to primary care. Keywords: self medication; analgesics; NSAIDs; paracetamol; diclofenac; ibuprofen; pharmacy; Guinea; Conakry; drug safety; public health.

Pseudomonas aeruginosa, a Gram-negative opportunistic pathogen is well known for life-threatening acute infections among the human population. The bacterium can withstand most antibiotics by using their high levels of inherent and acquired resistance mechanisms such as Biofilm-EPS, Persistence, and Quorum sensing (QS). Owing to the importance of adaptive antibiotic multi-drug resistance of P. aeruginosa, the current investigation is aimed to explore the phytochemicals derived from mangrove plants as potential agents to control biofilm and drug resistance mechanisms through a multi-mechanistic computational approach. For identifying potential compounds and target, In-silico drug repurposing technique is implemented by docking/virtual screening of 49 phytochemical compounds against 18 proteins involved in the Persister Cell formation, QS, and EPS synthesis in P. aeruginosa which resulted the proteins RelA and SpoT (persistence), PqsA, and PqSR (QS), and PelA and PelB (EPS synthesis) and compounds Taraxerone and Taraxerol to be potential. The results of docking were well corroborated with MD simulations. These targets and compounds explored through in-silico approach, are found to target potential antimicrobial pathways involving EPS synthesis, persistence genes, and QS, aiming to enhance antibiotic efficacy. Further, this study could be reference for in-vivo and in-vitro investigations to evaluate the further effectiveness of the compounds and potentiality of the proteins for MDR therapeutics of P. aeruginosa.

BackgroundRising antimicrobial resistance rates, require new therapeutic approaches such as antimicrobial peptides (AMPs), which are part of the innate immune defense, as alternatives to antibiotics. In this study, we aim to unravel the antibacterial activity of human histone H1.2 peptide against Pseudomonas aeruginosa and its potential immune modulatory role. MethodsWe used a hemofiltrate peptide database for antimicrobial peptide prediction to identify novel human AMPs. Thirteen sequences of histone H1 were identified as putative AMPs, synthesized, and tested against bacterial ESKAPE pathogens in a radial diffusion assay. SYTOX green assay, electrophoretic mobility shift assay, and differential proteomics assays were conducted to determine the mode of action of H1.2 peptide fragment. A crystal violet assay was performed to evaluate the inhibition of biofilm formation. The cytotoxicity of the peptide was tested in LDH and Alamar assays. Finally, to visualize the contributions of H1.2 in NETs formation, scanning electron microscopy was performed. ResultsThe H1.2 peptide inhibited the growth of P. aeruginosa in a dose and pH-dependent manner without cytotoxicity towards mammalian THP-1 cells. It acts on intracellular targets to inhibit the growth of P. aeruginosa. STRING analysis from the differential proteomics assay showed that H1.2 targets the downregulation of proteins involved in the biogenesis of outer membrane proteins, including the folding and trafficking of outer membrane proteins across the cytoplasmic membrane. Scanning electron microscopy images showed that H1.2 forms NET-like structures capable of trapping and immobilizing P. aeruginosa. ConclusionThe characterized antimicrobial activity of H1.2 points to a role for human histone H1 fragments in innate immunity and may represent a promising approach for the development of novel antibacterial therapies. Graphical Summary O_FIG O_LINKSMALLFIG WIDTH=192 HEIGHT=200 SRC="FIGDIR/small/724237v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@1778ddborg.highwire.dtl.DTLVardef@26430org.highwire.dtl.DTLVardef@ffbfa2org.highwire.dtl.DTLVardef@7e38ae_HPS_FORMAT_FIGEXP M_FIG C_FIG Sec transport and BAM complex system including chaperone proteins and quality control proteases are inhibited by H1.2 in Pseudomonas aeruginosa.Outer membrane proteins (OMPs) are synthesized in the cytoplasm and transported across the inner membrane via the Sec translocase, assisted by SecA/SecB or ribosomes. In the periplasm, they are escorted by chaperones such as SurA to the BAM complex for insertion into the outer membrane. Here, we show that H1.2, an antimicrobial peptide, targets membrane biogenesis in P. aeruginosa through downregulating Sec translocase (SecA/SecB and SecYEG), SurA, and BAM complex. Therefore, leading to improper transfer, folding and insertion of OMPs into the outer membrane. Normally, misfolded proteins are degraded by the protease MucD to prevent toxic aggregation in the bacteria. However, with H1.2 inhibiting MucD the proteotoxic stress is exacerbated, ultimately compromising bacterial homeostasis and viability. Figure created using BioRender.com.

Pseudomonas aeruginosa is a clinically significant bacterial pathogen that poses a serious threat to aquaculture. However, there are limited information on Massilia isolates against pathogenic P. aeruginosa in aquaculture. In the present study, a facultative predator, M. varians isolate P2-4, was isolated from aquaculture sediment using Chinese mitten crab Eriocheir sinensis-pathogenic P. aeruginosa as the prey bacterium, and its genomic feature, bacteriolysis-related genes, safety, bacteriolytic spectrum, and in vitro and in vivo antibacterial effects against pathogenic P. aeruginosa in E. sinensis were further characterized. Isolate P2-4 consisted of one chromosome and one plasmid (with a total of 75 tRNAs, 7 5S rRNAs, 7 16S rRNAs, 7 23S rRNAs, 34 sRNAs, 5,238 coding genes, 20 genomic islands, 1 prophage, 23 insertion sequences, and 102 repeat sequences), and harbored 19 bacteriolysis-related genes (pilA, pilB, pilC, pilD, pilF, pilG, pilH, pilM, pilO, pilP, pilQ, pilS, pilR, pilT, mltA, mltB, mltC, mltD, and dacB) associated with cellular motility and cell wall lysis. In addition, the isolate carried no virulence genes, was unable to produce haemolysin, hydrogen sulfide, nitrite and ammonia, and avirulent in E. sinensis with a 7-day acute intraperitoneal LD50 value of above 5.0 x 108 CFU/mL. Furthermore, the isolate possessed a wide bacteriolytic spectrum against pathogenic Shewanella algae, Aeromonas caviae, A. hydrophila, and Photobacterium damselae besides P. aeruginosa, exhibited bacteriolysis rates of 99.35% to 99.99% towards the pathogenic P. aeruginosa at 1.0x103 to 1.0x10{square} CFU/mL, and displayed relative percentage survivals of 42.31% to 73.08% against P. aeruginosa infection in E. sinensis at doses of 6.0 x 103 to 6.0 x 105 CFU/g diet. To our knowledge, this study for the first time demonstrates a M. varians strain as a potential biocontrol agent against pathogenic P. aeruginosa in aquaculture.

ObjectiveTo quantify waiting time in days for scheduled outpatient specialist consultations and to compare waiting time between standardized and non-standardized access pathways in Ecuadorian public hospitals. MethodsWe analyzed hospital-based survey data from Ecuadorian public hospitals, restricted to adults attending a scheduled outpatient specialist consultation (n = 4,436). Emergency care, unscheduled urgent visits, procedures, and follow-up visits were excluded by design. Access pathway was classified from participants self-report as standardized (institutional or system-based) or non-standardized (informal or non-system-based). Waiting time, defined as the number of days between obtaining the appointment and attending the consultation, was compared using the Mann-Whitney U test. Sociodemographic correlates of non-standardized access were examined using adjusted logistic regression, and adjusted median differences were estimated using quantile regression ({tau} = 0.50). Analyses were stratified into direct-access specialties and referral-required specialties. ResultsNon-standardized access was associated with shorter waiting times than standardized access. In adjusted median regression, non-standardized access was associated with a 3.2-day shorter median waiting time (95% CI -4.6 to -1.8). The difference was larger in direct-access specialties (-15.0 days, 95% CI -15.0 to -6.0) than in referral-required specialties (-5.0 days, 95% CI -5.0 to 0.0). ConclusionAmong patients who attended a scheduled outpatient specialist consultation in Ecuadorian public hospitals, non-standardized access was associated with shorter waiting times, particularly in direct-access specialties. These findings suggest that, within routine outpatient care, parallel access pathways may shape timeliness and warrant greater transparency in appointment allocation and referral coordination.

Introduction -- Emergency Medical Dispatch Systems (EMDS) can reduce delays in accessing emergency care by providing structured communication, triage, and coordination. However, such systems remain absent or underdeveloped in most low- or middle-income countries (LMICs). This study aimed to establish international consensus on essential EMDS components to inform global guidance. Methods -- We convened a multidisciplinary expert group to draft a preliminary list of essential components for three EMDS levels reflecting resource availability and system maturity. We then conducted a three-round Delphi with international experts to reach consensus on core EMDS components. Components which had [≥]75% agreement were included, those with [≥]75% disagreement were excluded. Components not achieving consensus by Round 3 were removed. Results were analysed overall and stratified by respondents' country income level. A subsequent online expert meeting resolved inconsistencies and finalised the component list. Results -- The expert group generated 111 components for each of three EMDS levels (Foundational, Emerging, and Established) spanning 11 operational domains. Of the 68 experts invited to the Delphi, 43 participated in Round 1 and 30 in Round 3. Across all Delphi rounds, 289 components reached consensus for inclusion. The consensus resulted in a final list of 227 components (63 Foundational, 84 Emerging, and 80 Established). Consensus agreement clustered around core EMDS domains including communication, structured call-taking and prioritisation, advice-giving, resource dispatch and tracking, and foundational governance and data functions, whereas items showing either non-consensus or consensus disagreement were typically technology-dependent or context-specific. Conclusions -- This international consensus offers guidance for EMDS development across diverse resource settings and provides a scalable roadmap to strengthen emergency care systems.

Background Antimicrobial stewardship (AMS) and infection prevention and control (IPC) are complementary strategies to improve patient safety and address antimicrobial resistance (AMR). In low- and middle-income countries (LMICs), they are often implemented separately, reducing effectiveness. Evidence on integrating AMS and IPC in routine hospital practice remains limited. Objective To evaluate the feasibility of an integrated AMS-IPC improvement approach and describe changes in implementation in Vietnamese hospitals. Methods We conducted a multisite quality improvement initiative in four hospitals within the national AMR surveillance network in Viet Nam (March-September 2025). We used US-CDC tools to guide the implementation, including the Global Antibiotic Stewardship Evaluation Tool (G-ASET) and the Infection Control Assessment and Response (ICAR) tool. Baseline assessments were followed by feedback, multidisciplinary action planning, and targeted capacity building. Follow-up occurred 2-5 months later. Changes were analysed descriptively using quantitative scores and qualitative synthesis, and reported following the SQUIRE 2.0 guidelines. Results All hospitals had established IPC programmes at baseline, while AMS maturity varied. G-ASET scores improved across all sites, with greater gains in hospitals starting from lower baselines. Key improvements included leadership and governance, education and training, stewardship actions, and monitoring and reporting. IPC practices aligned with AMS priorities also improved, particularly transmission-based precautions, environmental cleaning, and cross-team coordination. Infrastructure-dependent areas, such as water safety, showed limited short-term progress. Conclusions An integrated AMS-IPC approach using repeated assessment and feedback is feasible and associated with meaningful improvements. This model offers a scalable strategy for strengthening hospital responses to AMR in LMICs and informs national programmes.

BackgroundThe global rise of multidrug-resistant (MDR) bacteria represents a critical public health threat, and Romania ranks amongst the most affected countries in Europe. As conventional therapy increasingly fails, bacteriophage therapy has re-emerged as a promising alternative to antibiotics. Urban rivers, contaminated with resistant bacterial strains, represent an underexplored and accessible reservoir for the isolation of lytic phages with therapeutic potential. MethodsTwo bacteriophages, 17M_Ec17_D and 22C_Ec22_D, were isolated from the Dambovita River, Bucharest, Romania, using MDR E. coli as host bacteria. Phage characterization included plaque morphology, transmission electron microscopy, and host range assessment by spot assay against 30 MDR E. coli isolates. Whole genome sequencing was performed on Illumina MiSeq and Oxford Nanopore Technologies MinION platforms, followed by bioinformatic analysis including taxonomic classification, lifestyle prediction, and functional annotation. ResultsBoth phages formed clear plaques and were classified as Kayfunavirus (17M_Ec17_D, Podoviridae-like) and Kagunavirus (22C_Ec22_D, Siphoviridae-like) with nucleotide similarities of 89.2% and 71.4% to their closest relatives, respectively, suggesting both are candidates for novel species. Host range analysis revealed lytic activity against 13% and 10% of tested MDR isolates, with complementary infection profiles. Genomic analysis confirmed a strictly lytic lifestyle for both phages, supported by the presence of holin and spanin genes and the absence of lysogenic modules, antibiotic resistance genes, and virulence factors. ConclusionsTo the best of our knowledge, this is the first study conducted in Romania to isolate and genomically characterize lytic bacteriophages targeting MDR E. coli. The characterized phages represent safe therapeutic candidates whose complementary host ranges suggest potential application as part of phage cocktail to broaden antimicrobial coverage against MDR infections.

The facultative methylotroph model organism Methylorubrum extorquens AM1 is a known lanthanide user, which has shed light on the role of rare-earth metals in biochemistry. The characterization of a methanol dehydrogenase (MDH) protein which requires lanthanides as an enzymatic cofactor outlined the question of how these metals are acquired from the environment. It has been proposed that mesophilic organisms as M. extorquens AM1 can produce siderophore-like molecules, which chelate, transport and traffic rare-earth elements into the microbial cell. Therefore, we performed the bioinformatic and chemical investigation of M. extorquens AM1 by using genome mining, the CAS and arsenazo assay, molecular networking and chemical analytical techniques. Our results showed that indeed Methylorubrum extorquens AM1 harbored a gene cluster to produce metal chelators. The chemical analysis confirmed the production of the known hybrid hydroxamate-citrate siderophores schizokinen A and N-deoxyschizokinen A, which are very likely the side products of the transformation of schizokinen and N-deoxyschizokinen. The determination of the lanthanide chelation activity of the schizokinen siderophores series against three different lanthanides (La, Eu and Lu) showed no coordination activity, thus ruling out the involvement of schizokinen siderophores in rare-earth metal transport.

The gut microbiome plays a central role in host metabolism, immune function, and overall health, with disruptions in microbial composition (dysbiosis) being associated with a range of metabolic, inflammatory, and infectious conditions [1,2]. Consequently, strategies aiming to modulate the microbiome require selective activity that preserves beneficial commensals while limiting pathogenic organisms [3]. In this context, ThymoQuin(R)--a cold-pressed, standardized black cumin (Nigella sativa) seed oil developed by TriNutra Ltd. and defined by [≥]3% thymoquinone (TQ), controlled p-cymene levels, and low free fatty acids ([≤]1.25%)--was evaluated for its microbiome-relevant activity. In vitro minimum bactericidal concentration (MBC) assays across three independent batches demonstrated a biphasic, dose-dependent response. At intermediate concentrations (0.25-0.5%), Streptococcus thermophilus was strongly stimulated (up to 53-fold) and Lactiplantibacillus plantarum fully preserved, while Klebsiella pneumoniae was effectively reduced (>94%). Akkermansia muciniphila exhibited stable viability at concentrations below 1%, with reductions only observed at 1%. This is notable given its role as a mucin-degrading commensal that has been linked to metabolic health, but whose abundance may vary across physiological and disease contexts [4,5]. At concentrations [≥]1%, selective effects diminished, resulting in broader antimicrobial activity and reduced specificity. These findings indicate a defined concentration range in which selective microbiome modulation is maintained, whereas higher thymoquinone levels may increase the risk of non-selective detrimental effect on microbes.

Antimicrobial resistance is an impactful One Health issue. One of its drivers is the extensive use of antibiotics in both human and animal production systems, and despite regulatory restrictions on antibiotic use in poultry farming, antimicrobial resistance remains a major challenge. Consequently, animals are at higher risk of harder-to-treat diseases and play a role as resistance reservoirs, highlighting the need for alternative antimicrobial strategies. Towards this end, antimicrobial peptides (AMPs) have emerged as promising candidates due to their broad-spectrum activity and lower propensity to induce resistance. However, the effectiveness of AMPs against poultry pathogens, and in particular multi drug-resistant strains, is largely unclear. To tackle this question, we evaluated the synthetic AMP SET-M33 against four species of clinically relevant pathogens in poultry, namely Escherichia coli, Salmonella enterica, Enterococcus faecalis and Enterococcus cecorum. Using a panel of 141 field isolates, we found that SET-M33 broadly inhibited bacterial growth at low micromolar concentrations (median MICs of 2.5 M and 5 M for Gram-negative and Gram-positive strains, respectively), including in multi drug-resistant isolates. To examine the potential impact of SET-M33 on the host, we established a new in vitro co-cultivation system using chicken intestinal organoids. We found that SET-M33 retains its antimicrobial activity in organoid-microbe co-cultures at concentrations that preserved host viability. These findings demonstrate the potential of SET-M33 as a new antimicrobial agent against pathogens in poultry.

Fecal microbiota transplantation (FMT) is an effective therapy for recurrent Clostridioides difficile infection and is increasingly explored for other dysbiosis-related disorders. However, its implementation as a regulated therapeutic strategy still requires robust donor screening, biosafety frameworks, and standardized processing workflows. Here, we describe the establishment of the first fecal microbiota biobank in the south of Brazil and evaluate the incorporation of metagenomic sequencing as a complementary layer of donor safety assessment. A structured donor selection pipeline based on international guidelines was implemented, integrating clinical screening, biochemical and serological testing, and microbiological analyses. Of 100 screened candidates, only four donors met all eligibility criteria and were included in the biobank, highlighting the stringency of the selection process. Shotgun metagenomic sequencing revealed a diverse resistome across all donors, including a shared core set of resistance-related genes alongside marked interindividual variability. Dominant antibiotic resistance genes included tetracycline-associated determinants, as well as ermF, CfxA-type {beta}-lactamases, and aminoglycoside-modifying enzymes, each linked to specific gut taxa. Notably, the relatively high abundance of tetW and ermF in Bacteroides fragilis suggests that this dominant commensal species may act as a reservoir for tetracycline and multidrug resistance determinants within the intestinal microbiota. Rather than serving as exclusion criteria, such determinants highlight the importance of integrating functional genomic profiling into donor characterization. Overall, this study provides a framework for microbiota biobank implementation and supports the use of metagenomics as a complementary strategy to improve biosafety and functional assessment in FMT.

BackgroundCystic fibrosis (CF) is an autosomal recessive genetic disorder that leads to chronic infection and mucus retention in the lungs, with lung function gradually deteriorating through recurrent pulmonary exacerbations (PEx). Virulence factors (VFs) of Pseudomonas aeruginosa and Staphylococcus aureus are thought to contribute to pulmonary exacerbations. Our study objective was to identify VF genes related to PEx, high Pseudomonas abundance, and high Staphylococcus abundance in persons with CF (pwCF). MethodsThis was an ancillary study of pwCF treated with IV antibiotics for PEx between 2016-2020 at Childrens National Hospital. Using shotgun metagenomics and ShortBRED, we identified bacterial VF genes and used DESeq2 to determine differential expression of VF genes across comparators. ResultsTwenty-two PwCF experienced 43 PEx. The study cohort had a mean age of 14.6 years, 41% female, 59% white, 36% Hispanic, and 45% had an F508del homozygous CFTR mutation. Minimal differences in VF gene abundance were identified across clinical state. The most differentially increased VF genes found in Pseudomonas high samples were associated with an aminotransferase (log2FC 25.9), flagellar biosynthesis (log2FC 8.3), and type VI secretion systems (log2FC 8.2). The most differentially increased VF genes found in Staphylococcus high samples were an exotoxin (log2FC 26.7), macrolide phosphotransferase (log2FC 25.8), pathogenicity island proteins (log2FC 25.2 and 24.7), and VOC family proteins (log2FC 24.8). ConclusionsThese findings demonstrate that specific VFs associated with immune modulation, motility secretion systems, bacterial motility, and antibiotic resistance are related to P. aeruginosa and S. aureus abundance, providing potential targets for more personalized antimicrobial interventions.

BackgroundTransfer of Streptococcus agalactiae, or Group B Streptococcus (GBS) from parent to newborn during delivery can produce life-threatening infections in neonates. Probiotics could potentially prevent GBS colonization in pregnant individuals. We conducted a systematic review and meta-analysis to evaluate the effectiveness of probiotic administration in treating Group B Streptococcus colonization. MethodsMEDLINE, ClinicalTrials.gov, PROSPERO, and the Cochrane, Wild Card, Central Register of Controlled Trials were searched from the July 2015 of each database until July 2025 that completed a randomized controlled trial which compared Probiotic versus control. We utilized the Cochrane Risk of Bias 2.0 (RoB 2) tool to assess bias in the systematic review. Results14 randomized controlled clinical trials met our inclusion criteria. The trials used oral probiotic administration compared to either a placebo or a control group. A meta-analysis showed that probiotic administration produced a statistically significant decrease in the rate of GBS colonization in pregnant individuals. The individual studies ranged from four showing great effectiveness, while the other 10 studies showed a range of effectiveness, from partially effective to no effectiveness in preventing GBS colonization. ConclusionOverall, probiotics were effective in lowering infection rates of GBS, but individual studies showed great variability. Probiotics show promise in decreasing GBS colonization in pregnant people, but more studies need to be performed in order to use them effectively and decrease antibiotic usage.

Background: Tuberculosis (TB) remains the leading infectious cause of death worldwide, with India accounting for nearly one-fourth of global TB cases. Ni-kshay, the countrys digital case-based TB notification platform is rich in data pertaining to the continuum of care of TB patients. This study aims to develop a standardized analytical approach to programmatic data to identify predictors of unfavourable treatment outcomes and mortality among adult drug-sensitive TB patients at the state level for Maharashtra during 2021 and 2022. Methods: Two separate analyses were undertaken comparing treatment success with: (1) unfavourable outcomes (death, treatment failure, loss to follow-up, regimen change, or not evaluated); and (2) mortality. Multivariate logistic regression was used to compute adjusted odds ratios (aOR) for key risk factors, adjusting for age, gender, and weight. Results: The final cohort included 323,124 cases for unfavourable outcome analysis and 315,579 cases for mortality analysis. Increasing age, male gender, lower body weight, known HIV and diabetes comorbidities, tobacco and alcohol consumption, and "unknown" status for behavioural risks and comorbidity status were significantly associated with increased odds of both unfavourable outcomes and mortality. Conclusions: This study highlights the utility of programmatic data in identifying high-risk TB patients and offers a reproducible analytic framework.

Urinary tract infections (UTIs) are the most prevalent bacterial infections globally, and their management increasingly challenged by antimicrobial resistance (AMR). Probiotics offer a promising approach to mitigate AMR by competitively excluding uropathogens and enhancing host immunity by producing immune modulators. Despite being potential, key gaps persist between the discovery of uroprotective probiotic strains and optimization of formulations for urinary tract delivery. Here, we analyzed the urinary microbiome of UTI patients and healthy individuals to identify potential probiotic candidates for the prevention and management of UTIs. Publicly available 16S rRNA amplicon sequencing data of the urinary tract were processed using a standardized pipeline for sequence quality assessment, taxonomic assignment, and microbial function prediction. Comparative analysis showed a significant shift in microbial composition between UTI patients and healthy controls. The dominated phyla identified included Acidobacteriota, Actinobacteriota, Bacteroidota, Campylobacterota, Cyanobacteria, Firmicutes, Fusobacteriota, Patescibacteria, Proteobacteria, and Synergistota. Overall differential abundance analysis revealed Escherichia coli as the predominant UTI-associated species, while Lactobacillus crispatus was enriched in healthy samples. Additionally, predictive functional analysis indicated that metabolic pathways associated with beneficial microbes were enriched in the healthy group. Overall, the study highlights the association of distinct urinary microbiome signatures with infection status, which supports L. crispatus as the most promising probiotic for UTI prevention and control.

Resistance to a particular antibiotic can make bacteria sensitive to others, a phenomenon known as collateral sensitivity (CS). This study explored potential CS in clinical and experimentally evolved drug-resistant Pseudomonas aeruginosa (PA) and investigated underlying mechanisms. Whole-genome sequencing and RNA-seq were analyzed to identify genetic and transcriptional correlations. In vitro efficacies were assessed with co-and sequential-exposure regimens. Multiple CF isolates and experimentally evolved gentamycin (GEN) resistant strains consistently exhibited strong CS to novobiocin (NOV). Comparative genomics revealed pmrB gain-of-function mutations, which was further supported by transcriptomic signatures of pmrAB activation. Transcriptomic data suggests potential outer-membrane remodeling characterized by polyamine accumulation and compromised porin channel expression. Additionally, the reduction in proton motive force (PMF) further explains the possible mechanism underlying GEN resistance. As NOV efflux is PMF-dependent, this energetic deficit created a PMF-efflux mismatch, leading to hypersensitivity to NOV. Notably, sequential GEN[->]NOV treatment effectively restricted the emergence of GEN resistant subpopulations. Overall, our data suggest GEN resistance in PA may arises through envelope remodeling and reduced PMF, which impairs efflux pumps and creates hypersensitivity to NOV. Exploiting this PMF-efflux mismatch with sequential treatment effectively restricted the emergence of GEN resistance.

Phage therapy offers promise to combat antimicrobial resistance, including drug-resistant tuberculosis (TB). Understanding phage activity against Mycobacterium tuberculosis (Mtb) adapted to physiologic microenvironments, such as hypoxia and acidity in granulomas, is essential since these conditions induce non-replicating states. We evaluated a phage combination against Mtb under hypoxic, acidic (pH 5.5), and stationary-phase conditions in vitro. In planktonic Mtb growth conditions, phage concentrations increased around day seven followed by a significant reduction in Mtb H37Rv load, which was maintained over 31 days. Phage addition prevented regrowth was observed with rifampicin and isoniazid alone. Individual phage stability was differentially affected by acidic media conditions, resulting in variability of antimycobacterial activity. In hypoxic conditions and stationary growth experiments, phage titers remained stable over time with no change in mycobacterial load compared to controls. Model-based predictions were able to adequately capture phage-mycobacterial interactions with and without rifampicin. The lack of antimycobacterial activity in assays with non-replicating mycobacteria suggest that phages need actively replicating mycobacteria to exert lytic activity. Stable phage concentrations in assays with non-replicating mycobacteria suggests low grade phage replication in these conditions. Established models can support future study design through simulations of different experimental scenarios.