Sepsis was identified using Sepsis-3 criteria based on the Sequential Organ Failure Assessment score and quick SOFA criteria. The clinical analysis was descriptive rather than interventional, so the reported associations do not establish that any antibiotic regimen, patient characteristic, or dosing strategy caused an improvement or deterioration in outcomes.

Among the 196 positive cultures, the average hospital stay was 22 days. For patients who required intubation and transfer to the intensive care unit, the average stay rose to 41 days. Mortality was higher among patients aged 65 or older in both sexes. It was 8 of 37 men younger than 65, compared with 24 of 69 men aged 65 or older; among women, it was 4 of 44 younger patients and 8 of 46 aged 65 or older. Men had higher observed mortality in each age group, although the analysis did not demonstrate that age or sex caused the differences.

Cardiovascular disease was the most frequently recorded concomitant condition, reported in 38% of the study population, and diabetes mellitus was second at 24%. These findings describe the clinical profile of the analyzed group. As a single-center retrospective series based on blood cultures, the study did not include an untreated or non-sepsis comparison group and could not determine whether the observed lengths of stay, mortality, or resistance patterns were representative of other hospitals or populations.

The isolates included a broad range of bacteria, with Staphylococcus species predominating. The investigators also identified enterobacteria such as Klebsiella and Escherichia coli producing extended-spectrum beta-lactamases, along with Acinetobacter baumannii, Providencia stuartii, Citrobacter freundii, and Klebsiella oxytoca. The presence of ESBL-producing enterobacteria and A. baumannii complicated treatment choices in the study population, while the rare isolates demonstrated the etiological diversity among the sampled patients.

Resistance patterns differed among the organisms examined. Among the Gram-positive isolates, Staphylococcus haemolyticus showed 37% resistance to erythromycin and approximately 28% resistance to levofloxacin, while Enterococcus faecalis showed high resistance to ciprofloxacin and erythromycin. The authors associated the macrolide and fluoroquinolone resistance with the widespread use of these drug classes over preceding years. S. aureus had very low measured resistance in this sample, and no Gram-positive isolate was resistant to vancomycin, teicoplanin, or linezolid.

Among the Gram-negative organisms, ESBL-producing K. pneumoniae had the highest resistance to most tested penicillins and cephalosporins, and the pattern for A. baumannii was not substantially different. By comparison, K. oxytoca and Proteus mirabilis were susceptible to most antibiotics tested. These results identify resistance in the sampled blood-culture isolates; they do not determine which drugs were administered, whether prescribed therapy was appropriate for each isolate, or whether resistance was associated with an individual patient’s outcome.

The review also describes how sepsis-related physiological changes can alter antibiotic exposure. Capillary leak and fluid movement into interstitial spaces expand the distribution volume of hydrophilic drugs such as aminoglycosides, beta-lactams, glycopeptides, and lipopeptides, which can increase loading-dose requirements. Augmented renal clearance, commonly operationalized as creatinine clearance of at least 130 mL/min/1.73 m², may further accelerate elimination and has been associated with antibiotic underdosing. Hypoalbuminemia may increase the free fraction and clearance of highly protein-bound drugs such as ceftriaxone, potentially reducing drug exposure near the end of a dosing interval.

Within those pharmacological constraints, the authors discuss pharmacokinetic and pharmacodynamic dosing strategies. Prolonged or continuous beta-lactam infusions are intended to maintain concentrations above the pathogen’s minimum inhibitory concentration, while high loading doses and subsequent adjustments are described for vancomycin. High-dose, extended-interval regimens are presented for concentration-dependent drugs such as aminoglycosides and fluoroquinolones, with therapeutic drug monitoring particularly important for aminoglycosides. The study concludes that collaboration between physicians and clinical pharmacists is important for individualized antibiotic dosing, but the retrospective blood-culture data do not directly test these strategies or establish their clinical effectiveness in the included patients.

Subject of Research: Antibiotic resistance, pathogen distribution, and pharmacokinetic challenges in patients with sepsis

Article Title: Antibiotic treatment in sepsis–etiological structure, antibiotic resistance, and pharmacological challenges: A retrospective analysis

Article References: Kobakova, Y. A., Kirkova-Bogdanova, A. G., Vakrilova Becheva, M. S., Semerdzhieva, N. E., Ivanova, S. A., Chaneva, M. S., Atanasova, V. P., Bashov, I. E., Yonchev, Y. T., Todorov, R. F., Bashev, N. Z., Teneva, D. N., Danov, K. V., Moneva-Sakelarieva, M. G., Atliev, K. T., Kyosev, V. S., Pavlova, S. M., & Atanasov, P. Y. (2026). Antibiotic treatment in sepsis–etiological structure, antibiotic resistance, and pharmacological challenges: A retrospective analysis. Pharmacia, 73, Article e212551. https://doi.org/10.3897/pharmacia.73.e212551

Image Credits: AI Generated

DOI: 10.3897/pharmacia.73.e212551

Keywords: sepsis, blood cultures, antibiotic resistance, pathogen distribution, pharmacokinetics, pharmacodynamics, therapeutic drug monitoring, antimicrobial stewardship, retrospective study, Antibiotic, treatment, etiological

Resistance to other commonly used antibiotics was lower: 26.5% for co-trimoxazole, 25.3% for tetracycline, 17.3% for erythromycin, 13.6% for cefoxitin and 7.4% for chloramphenicol. Ciprofloxacin and gentamicin each showed resistance in 3.1% of isolates. The abstract also reports that resistance patterns differed between the study sites and that 38.5% of multidrug-resistant isolates came from neonates.

The researchers analysed data from population-based surveillance at the Basse and Fulladu West Health and Demographic Surveillance Sites in the Upper River and Central River Regions. All children under 5 who resided in the two catchment areas were under surveillance, and cases of invasive bacterial disease were identified at all 11 health facilities serving those sites. When indicated under standardised criteria for suspected sepsis, pneumonia or meningitis, investigators collected blood, cerebrospinal fluid, lung aspirates and/or pleural aspirates.

Culture-positive samples underwent standard microbiological identification. Antibiotic susceptibility was assessed using the Kirby-Bauer disk diffusion method, with results interpreted according to Clinical and Laboratory Standards Institute guidelines. The study was retrospective and population-based, covered two surveillance sites and a September 2019–December 2023 collection period, and the reported results concern the 162 S. aureus isolates tested.

The abstract identifies high penicillin resistance and measurable multidrug resistance and MRSA prevalence among isolates from children younger than 5 in the study setting. The reported data cover the two Gambian surveillance regions and 11 facilities, so the findings describe the study population and period rather than establishing resistance trends beyond that setting. The authors state in the abstract that the results reinforce the importance of ongoing antimicrobial-resistance surveillance, prudent antibiotic use and targeted interventions.

Subject of Research: Antibiotic resistance among Staphylococcus aureus isolates from children under 5 in two regions of The Gambia

Article Title: Antibiotic resistance profile of Staphylococcus aureus in pediatric cases from rural Gambia

Article References: Jallow, M. J. S., Osei, I., Wutor, B. M., Barjo, O., Omotosho, M., Wally, M., Minteh, M., Kuyateh, A., Drammeh, M. M., Mendy, S., Badji, H., Jallow, S. J., Sarwar, G., Salaudeen, R., & Mackenzie, G. A. (2026). Antibiotic resistance profile of Staphylococcus aureus in pediatric cases from rural Gambia. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14487-w

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14487-w

Keywords: Staphylococcus aureus, antimicrobial resistance, MRSA, multidrug resistance, penicillin resistance, pediatric infections, Gambia, population surveillance, bacterial sepsis, Kirby-Bauer testing, Antibiotic, resistance

The patient arrived at the emergency department with severe, immobilizing lumbar pain, the kind of presentation that immediately raises concern for a spinal infection in anyone with diabetes. Magnetic resonance imaging confirmed the clinical suspicion of spondylodiscitis, an infection of the intervertebral disc and adjacent vertebrae that can destroy spinal structures if left untreated. But the real diagnostic drama unfolded in the microbiology laboratory, where Helcococcus kunzii was isolated from four separate blood culture sets, a finding that established bacteremia and pointed to the organism as the likely cause of the spinal infection rather than an incidental contaminant.

Helcococcus kunzii is a fastidious, facultatively anaerobic gram-positive coccus that was first described in the 1990s and has since been reported in a surprisingly wide range of clinical conditions. Previous studies have documented the organism in infective endocarditis, umbilical abscesses, bacteremia, diabetic foot infections, and prosthetic joint infections. Diabetes mellitus has repeatedly been identified as a predisposing condition for infections caused by this pathogen, likely because chronically elevated blood glucose and impaired immune responses compromise the skin barrier and create opportunities for organisms that normally live on the skin surface to invade deeper tissues. The Stuttgart team notes that patients with diabetes and associated comorbidities that may compromise skin barrier integrity should be considered at particular risk.

During surgical intervention, the clinicians collected two swabs and two tissue samples from the infected spinal region. All four specimens yielded Helcococcus kunzii, and the organism was identified in every case using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, or MALDI-TOF MS, with log scores ranging from 2.30 to 2.52. These log scores, which measure how confidently the mass spectrometry system matches the spectral fingerprint of the unknown organism to a reference database, fall within the range typically accepted for reliable species-level identification. The consistency of the identification across blood cultures, swabs, and tissue samples left little doubt that this unusual organism was the true etiological agent of the spinal infection.

The technical significance of MALDI-TOF MS in this case cannot be overstated. Helcococcus kunzii is a fastidious organism that grows slowly and can be misidentified by conventional biochemical methods, which rely on patterns of metabolic reactions that overlap with those of other gram-positive cocci. Before the widespread adoption of mass spectrometry, organisms like Helcococcus were frequently misclassified or reported only at the genus level, obscuring their true clinical relevance. The authors argue that MALDI-TOF MS is essential for accurate identification of this organism and should be considered in cases of atypical spondylodiscitis, where routine cultures may yield organisms that conventional algorithms fail to resolve.

Treatment began with intravenous β-lactam antibiotics for ten days, followed by 13 weeks of oral β-lactam antibiotics, a strategy the authors describe as partial management with oral therapy. The transition from intravenous to oral antibiotics after such a short parenteral course is a topic of growing interest in infectious disease practice, particularly for bone and joint infections where prolonged therapy is standard. Oral β-lactams with high bioavailability can achieve serum concentrations sufficient to reach infected bone, and the Stuttgart case adds to the evidence that carefully selected patients can be managed safely outside the hospital for the majority of their treatment duration, reducing costs and the risks associated with long-term intravenous access.

Follow-up MRI performed before discharge showed no further evidence of spondylodiscitis, and at the 3-month follow-up visit the patient demonstrated clinical improvement. The combination of surgical intervention, targeted antibiotic therapy guided by mass spectrometry identification, and a predominantly oral antibiotic regimen appears to have produced a favorable outcome in a patient whose diabetes might otherwise have complicated recovery. The authors emphasize that the clinical diagnosis was established by MRI and the microbiological diagnosis by repeated isolation of the organism from blood and tissue specimens, a dual confirmation that strengthens the case for Helcococcus kunzii as a genuine pathogen rather than a bystander.

The broader lesson from this case is that the spectrum of organisms capable of causing pyogenic spondylodiscitis is wider than traditional teaching suggests. Spondylodiscitis is most commonly attributed to Staphylococcus aureus, followed by coagulase-negative staphylococci, streptococci, and enteric gram-negative bacilli. Unusual gram-positive organisms such as Helcococcus are rarely considered, and their identification depends on laboratories having both the technical capability and the willingness to pursue mass spectrometry identification of atypical isolates. The authors argue that Helcococcus kunzii should be considered a potential etiological agent of pyogenic spondylodiscitis, particularly in patients with diabetes mellitus and associated comorbidities that may compromise skin barrier integrity.

For clinicians, the case underscores the importance of considering unusual organisms in atypical presentations of spinal infection, especially in patients whose underlying conditions create opportunities for skin-dwelling bacteria to invade. For microbiologists, it highlights the indispensable role of MALDI-TOF MS in resolving fastidious gram-positive cocci that biochemical identification panels cannot reliably distinguish. And for patients with diabetes, it serves as a reminder that organisms normally confined to the skin surface can, when the barrier is compromised, travel through the bloodstream to distant sites including the spine, where they can cause serious and destructive infections that require prompt surgical and antibiotic intervention.

The report, published as an open access case study with a permanent DOI, adds a new entry to the growing list of clinical conditions associated with Helcococcus kunzii and demonstrates that even organisms long regarded as minor players in human infection can, under the right circumstances, produce serious disease. As mass spectrometry becomes standard equipment in clinical laboratories worldwide, more such cases are likely to emerge, revealing the true frequency of infections caused by organisms that were previously invisible to conventional diagnostic methods.

Subject of Research: Health & Medicine

Article Title: Helcococcus kunzii as a rare etiological agent of spondylodiscitis partially managed with oral antibiotic therapy in a patient with diabetes mellitus: a case report

Article References: Velázquez-Leonel, K., Bepperling, C., Regnath, T., Vazifehdan, F., & Santos, E. (2026). Helcococcus kunzii as a rare etiological agent of spondylodiscitis partially managed with oral antibiotic therapy in a patient with diabetes mellitus: a case report. BMC Infectious Diseases, 26(1), Article 1682. https://doi.org/10.1186/s12879-026-14341-z

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14341-z

Keywords: Helcococcus, kunzii, rare, etiological, agent, spondylodiscitis, partially, managed, oral, antibiotic, therapy, patient

The research team, led by M. Nazmul Hoque and M. Shaminur Rahman of Gazipur Agricultural University, collected milk samples from 20 lactating crossbred dairy cows on a commercial farm in the Dhaka district. Ten cows tested positive for subclinical mastitis using the California Mastitis Test, a diagnostic tool that detects elevated somatic cell counts without requiring visible signs of infection. These same 10 animals were then treated with a seven-day course of intramuscular ampicillin, a beta-lactam antibiotic, and azithromycin, a macrolide, the two most frequently administered antibiotics in dairy animals in Bangladesh. Milk samples were collected 24 hours after the final antibiotic injection, while milk from 10 healthy, untreated cows served as controls. The study design allowed the researchers to compare three distinct conditions: subclinical mastitis milk, antibiotic-treated milk, and healthy milk, each represented by 10 samples.

The sequencing effort was substantial. The team generated 327 million raw reads across all 30 samples, averaging 10.9 million reads per sample, using an Illumina NovaSeq 6000 platform. After rigorous quality control, adapter trimming, and removal of host-derived sequences using the Bos taurus reference genome, the researchers retained 94 to 99 percent of reads for microbial analysis. Taxonomic profiling was performed using Kraken2 with a custom database, while functional profiling of resistance determinants and metabolic pathways was conducted using the AMR++ pipeline aligned against the MEGARes v2.0 database and HUMAnN3 for KEGG pathway reconstruction. The bioinformatics workflow included negative extraction controls to monitor for reagent contamination, and any putative microbial or resistance gene signals detected in these controls were rigorously subtracted from the sample data sets.

The results revealed a striking pattern of microbial dysbiosis. Healthy milk samples exhibited the highest microbial richness, with a median of 129.5 observed taxa and a Shannon diversity index of 1.59. In contrast, subclinical mastitis milk showed reduced richness at 68.5 taxa and a Shannon diversity of 1.14, while antibiotic-treated milk had the lowest richness at 51.5 taxa, though its Shannon diversity of 1.41 was slightly higher than that of mastitis milk. Pairwise comparisons confirmed that healthy milk was significantly more diverse than both mastitis milk and antibiotic-treated milk. Interestingly, breed type also influenced diversity, with Local Zebu cows showing the highest richness at 142 taxa, followed by Holstein Friesian Cross at 101 and Sahiwal Cross at 81. Age-related trends showed that middle-aged cows between 5 and 8 years exhibited peak diversity, significantly higher than both younger and older animals.

At the phylum level, the bacteriome was dominated by three major groups: Pseudomonadota, Actinomycetota, and Bacillota, which collectively accounted for 90 to 99 percent of total bacterial abundance. Pseudomonadota was more abundant in antibiotic-treated milk at 51.75 percent and healthy milk at 40.57 percent compared to mastitis milk at 37.80 percent. Actinomycetota was enriched in mastitis milk at 40.67 percent and healthy milk at 32.80 percent, while Bacillota was highest in healthy milk at 16.19 percent. The persistence of Pseudomonadota in antibiotic-treated samples is clinically concerning because this phylum encompasses opportunistic pathogens including Escherichia coli, Klebsiella pneumoniae, and Acinetobacter johnsonii, all recognized mastitis agents. The researchers suggest that conventional antibiotic therapy may not effectively suppress these taxa, potentially due to biofilm formation, acquired resistance mechanisms, or the presence of persister cells that survive antimicrobial exposure.

At the species level, the study identified 665 bacterial species across all samples, with 471 detected in healthy milk, 272 in antibiotic-treated milk, and only 202 in mastitis milk. Just 26 species, or 3.91 percent, were shared across all three groups. Actinoalloteichus sp. and Vibrio furnissii emerged as the two most abundant species in the antibiotic-treated group, together accounting for over 70 percent of the total community. Staphylococcus aureus, a key mastitis-associated pathogen, was markedly enriched in mastitis milk at 1.74 percent relative abundance but nearly absent in healthy and antibiotic-treated samples. Conversely, A. johnsonii peaked in antibiotic-treated milk at 10.52 percent but was almost absent in mastitis milk, suggesting that the active mastitic microenvironment is unfavorable to its survival until antibiotic pressure suppresses competing taxa. Beneficial commensals such as Pseudomonas lundensis and Bacteroides thetaiotaomicron were heavily depleted or entirely absent in both mastitis and antibiotic-treated samples, confirming that disease-associated dysbiosis involves the severe displacement of organisms vital for maintaining udder homeostasis.

The resistome analysis revealed an even more alarming picture. The researchers identified 194 distinct antimicrobial resistance genes across all samples, with the majority detected in mastitis-associated microbiomes at 161 genes, followed by antibiotic-treated milk at 51 genes and healthy milk at just 24 genes. Mastitis milk possessed the largest fraction of unique resistance genes at 68.04 percent, cementing the unmanaged mastitic udder as a massive natural reservoir for diverse resistance determinants. In antibiotic-treated samples, macrolide resistance genes dominated, particularly the 23S rRNA mutation, reflecting strong selection pressure from clinical macrolide use. Aminoglycoside resistance mechanisms, including 16S ribosomal mutations and protective ribosomal proteins, were similarly enriched in antibiotic-treated milk, confirming treatment-associated resistance development. The strong positive correlation between macrolide and aminoglycoside resistance in antibiotic-treated milk indicates co-selection of resistance mechanisms under therapeutic pressure, where exposing the microbiome to one drug simultaneously selects for linked resistance mechanisms.

Correlation analysis identified key bacterial taxa that serve as major reservoirs for specific resistance genes. E. coli emerged as a prominent multi-resistance hub, displaying strong positive associations with tetracycline resistance genes, aminoglycoside resistance determinants, and multidrug efflux pump systems. A. johnsonii was strongly coupled with aminoglycoside resistance and beta-lactamase genes, which explains its competitive dominance in antibiotic-treated milk following therapeutic exposure. K. pneumoniae similarly acted as a resistance hub for efflux systems and tetracycline resistance. The community-dominating taxa Actinoalloteichus sp. and V. furnissii maintained broad baseline positive correlations across nearly all major resistance gene classes, including beta-lactams, macrolides, and tetracyclines, likely underpinning their ability to remain completely unsuppressed during active antibiotic treatment. Even healthy milk samples contained background reservoirs of resistance factors carried by commensals, including tetracycline and elfamycin resistance genes, emphasizing that the baseline milk microbiome naturally harbors low-level resistance determinants even in the absence of disease or therapeutic intervention.

Functional profiling using KEGG pathway reconstruction further clarified the adaptive mechanisms employed by the bacteriome during dysbiosis. Acinetobacter and Pseudomonas species displayed consistent positive correlations with core metabolic pathways, specifically membrane transport, amino acid metabolism, lipid metabolism, and xenobiotic biodegradation. This metabolic versatility is highly indicative of enhanced stress tolerance, as upregulating membrane transport and lipid catabolism allows these Gram-negative taxa to actively detoxify their microenvironment and drive cellular efflux, facilitating survival in antibiotic-exposed settings. In sharp contrast, S. aureus exhibited negative correlations with these core metabolic pathways while correlating positively with host-interactive processes, suggesting that this pathogen relies on specialized virulence factors rather than broad metabolic adaptability. The tightly coupled gut-associated commensal consortium demonstrated uniform positive links with carbohydrate metabolism, replication and repair, and biosynthesis of secondary metabolites, reflecting a stable homeostatic lifestyle focused on energy harvesting rather than stress-induced detoxification.

The study’s findings carry significant implications for antimicrobial stewardship in the dairy sector. The researchers emphasize that routine monitoring of antimicrobial resistance and judicious antibiotic use are urgently needed to curb resistance within dairy systems in Bangladesh and comparable settings. They also note that breed and age serve as additional modulatory factors, with Local Zebu cows and middle-aged animals maintaining the healthiest microbial profiles. However, the authors acknowledge several limitations, including the single-farm design, small group sizes, the combined ampicillin-azithromycin regimen that prevents assessment of each drug’s independent effects, and the collection of antibiotic-treated samples only 24 hours after the final dose, which may reflect acute drug exposure rather than persistent ecological changes. Future longitudinal, multi-farm studies integrating somatic cell counts, culture-based confirmation, metatranscriptomics, and metabolomics will be needed to validate these findings and clarify the mechanisms linking microbiome, resistome, and metabolic dynamics in bovine mastitis.

Subject of Research: Milk microbiome and antibiotic resistance genes in dairy cows with subclinical mastitis

Article Title: Subclinical Mastitis and Antibiotic Exposure Reshape the Milk Bacteriome, Resistome, and Metabolic Functional Profiles in Dairy Cows

Article References: Hoque, M. N., Rahman, M. S., Hossain, M. G., Rahman, M. T., Islam, T., & Hossain, M. A. (2026). Subclinical Mastitis and Antibiotic Exposure Reshape the Milk Bacteriome, Resistome, and Metabolic Functional Profiles in Dairy Cows. MicrobiologyOpen, 15(5), Article e70440. https://doi.org/10.1002/mbo3.70440

Image Credits: AI Generated

DOI: 10.1002/mbo3.70440

Keywords: dairy cows, mastitis, milk microbiome, antimicrobial resistance, metagenomics, antibiotics, Subclinical, Antibiotic, Exposure, Reshape, Milk, Bacteriome

The research team, led by Mouhamadou Moustapha Sow of Gaston Berger University in Saint-Louis, Senegal, conducted face-to-face interviews between March and April 2023 using an adapted CGIAR AMUSE Livestock questionnaire translated into Wolof and Pular. Participants were selected using Schwartz’ formula to determine the minimum sample size, and data were analysed descriptively with R Studio. The survey area was deliberately chosen: Kaffrine is one of the largest pastoral zones supplying meat and milk to major Senegalese cities, and during the dry season between February and June, when fodder becomes scarce, it serves as a place of refuge and transit for large-scale herders and their animals.

The respondents were predominantly men, at 86.8 percent, reflecting gender roles in rural Senegal, and 81 percent had never attended the formal government school system, having instead received education through Koranic schools. More than 60 percent of the herders had over 20 years of experience in pastoral livestock farming. Together, the surveyed households owned a herd of 13,856 animals, dominated by sheep at 37 percent and goats at 35 percent, followed by cattle at 20 percent, equines at 5 percent, and local poultry at just 3 percent. Small ruminants predominate because they adapt well to the mobility requirements of pastoral systems and serve as readily accessible economic capital that households can mobilize when needed.

Animal health pressures in the region are substantial. The most frequently reported disease was Plague of small ruminants, cited by 52.7 percent of respondents, followed by Lumpy skin disease at 39 percent, Pasteurellosis at 28.1 percent, Botulism at 24 percent, and Foot-and-mouth disease at 3.1 percent. This profile reflects the epidemiological conditions typical of Sahelian pastoral systems, where high animal densities and frequent herd movements facilitate the spread of highly transmissible viral diseases. The researchers note a troubling technical wrinkle: antibiotics are ineffective against viral infections, yet the occurrence of these viral diseases may indirectly drive increased antibiotic use for the prevention or treatment of secondary bacterial infections and disease-related complications.

Antibiotic use was generalized, with all surveyed livestock farmers reporting antibiotic use in their herds. The class profile was heavily skewed: 88.6 percent of farmers used tetracyclines, 10.4 percent used penicillins, and less than 1 percent used macrolides. The purposes were equally revealing. The vast majority, 94 percent, used antibiotics to treat sick animals, 42.7 percent used them prophylactically to prevent disease, and 33 percent used them as growth promoters. When disease broke out in a herd, 15.4 percent of owners administered antibiotics to prevent other symptoms from appearing and other animals from falling ill.

Who actually administers the drugs is a central concern for the study’s authors. In most cases, 50.9 percent, antibiotics were given by veterinary assistants with an intermediate level of training in animal health. In contrast, 45.9 percent of treatments were administered by animal health auxiliaries with no formal academic training, and only 26.8 percent of farmers consulted a veterinary surgeon. Self-medication remains widespread: antibiotics were administered directly by livestock owners in 40.5 percent of cases and by a family member in 4.5 percent of cases. The researchers attribute this to limited availability of animal health professionals and the unregulated circulation of antibiotics, which are commonly sold in the two largest weekly markets of Birkilane and Missira.

The survey also probed the practices that expose the food system most directly. Antibiotics were administered to lactating females whose milk is intended for human consumption by 65.5 percent of the farmers surveyed. Only 55 percent observed withdrawal periods before slaughter, with an estimated average duration of just 4 days, and the average treatment period for animals was estimated at 3 days. Non-compliance, inadequate dosages, and treatment interruptions were frequent. When no improvement was observed, 61 percent of farmers systematically stopped administering antibiotics, while 31 percent increased the dose and 30 percent continued treatment with the same antibiotic. Farmers’ reasons for stopping treatment were the ineffectiveness of antibiotics at 38 percent, the recovery of sick animals at 35 percent, and the high cost of antibiotics at 27 percent.

Knowledge about antibiotic resistance, strikingly, is not the problem. Overall, 63.6 percent of respondents could identify antibiotics available in the study area by their generic names, likely stemming from training courses and animal health initiatives carried out as part of livestock farming projects in the region. Moreover, 65.5 percent of livestock farmers recognised antibiotic resistance as an issue that could affect public health and the economy through loss of productivity, mortality due to bacterial diseases, and food safety. Yet only 28.2 percent remained sceptical about the harmful effects of resistant bacteria, and this awareness did not translate into more judicious use: only 5.5 percent of farmers reported implementing strategies to reduce antibiotic use, mainly improving vaccination coverage through annual campaigns organised by government veterinary services. Nineteen percent reported using traditional remedies, though they often lacked knowledge of appropriate dosages. Notably, none of the surveyed farmers implemented biosecurity improvement measures, and improved hygiene practices were generally not used as a means of preventing disease.

The study situates these findings within a broader One Health context. Antibiotic resistance was responsible for an estimated 1 million deaths worldwide in 2021 and sits on the World Health Organisation’s list of ten global health threats. Resistant bacteria exist in humans, animals, food and the environment, with limited barriers to the transmission of resistance genes across bacterial species and compartments. In Senegal, more than 80 percent of meat and milk production and sale is informal, and nearly 80 percent of the urban population eats at informal food markets that are affordable and easily accessible. Previous studies in Senegal have found products containing antibiotic residues being sold in Dakar, including milk, meat, and poultry products, and research elsewhere in Africa shows that communication and awareness-raising initiatives alone are not sufficient to reduce inappropriate antibiotic use.

The authors argue that expanding access to veterinary services, strengthening vaccination programmes, and enhancing antibiotic stewardship through an increased number of veterinary drug inspectors and adequate financial resources for effective monitoring and regulatory oversight are critical to mitigating antibiotic resistance and safeguarding sustainable food systems. Senegal’s 2018–2022 national action plan on antimicrobial resistance, implemented with support from partners such as the Food and Agriculture Organization of the United Nations, has improved knowledge of the issue among the general population and livestock farmers, and the survey results align with that observation. But the gap between knowing and doing remains the study’s most sobering message. Until herders in Kaffrine and beyond have real alternatives — accessible professionals, reliable vaccines, and enforced withdrawal periods — the tetracyclines will keep flowing, and the resistance genes they select will keep travelling along the farm-to-fork chain toward the dinner tables of Dakar.

Subject of Research: Antibiotic use practices in food systems in Senegal: a cross-sectional survey of pastoral livestock farming in Kaffrine

Article Title: Antibiotic use practices in food systems in Senegal: a cross-sectional survey of pastoral livestock farming in Kaffrine

Article References: Sow, M. M., Barry, K., Diamanka, A., Seck, R. M. N., Sow, A. I., Ly, C., Fall, A. G., Diouf, N. D., Dia, N. M., & Ciss, M. (2026). Antibiotic use practices in food systems in Senegal: a cross-sectional survey of pastoral livestock farming in Kaffrine. Pastoralism: Research, Policy and Practice, 16, Article 16798. https://doi.org/10.3389/past.2026.16798

Image Credits: AI Generated

DOI: 10.3389/past.2026.16798

Keywords: antibiotic resistance, One Health, pastoralism, Senegal, food safety, veterinary medicine, public health, Antibiotic, practices, food, systems, cross-sectional

The trial, led by Danish researchers including Henning Bundgaard, tested a radical idea: rather than committing to a fixed duration of antibiotic therapy, clinicians would stop treatment once patients met predefined criteria for clinical stability. The results showed that this response-tailored strategy successfully shortened the overall treatment duration without increasing the risk of death or the need for cardiac surgery. However, the approach came with a notable trade-off: rates of relapse of endocarditis or bacteraemia were tripled compared with standard-duration therapy.

Infective endocarditis remains a formidable clinical challenge. The infection destroys valve tissue, can seed emboli throughout the body, and carries substantial mortality even with modern care. Standard guidelines, including the 2023 European Society of Cardiology recommendations, have long endorsed prolonged antibiotic courses — typically four weeks for many cases and six weeks for more complex infections — on the assumption that complete eradication of bacteria from vegetations requires sustained drug exposure.

The original POET trial, published in 2019, had already challenged one pillar of conventional treatment by showing that switching stable patients from intravenous to oral antibiotics partway through their course was non-inferior to continued intravenous therapy. That finding, later reinforced by the Danish POETry implementation study, reshaped practice in many centers and reduced the burden of prolonged central venous catheter use. POET II now pushes the logic one step further by questioning the total duration itself.

In the response-tailored arm of POET II, antibiotics were discontinued once patients achieved clinical stability — defined by criteria such as absence of fever, hemodynamic stability, and lack of ongoing bacteremia — rather than after a predetermined number of weeks. The trial’s rationale, outlined in its design publication, was that a subset of patients may clear their infection adequately with shorter exposure, and that continuing antibiotics in these individuals offers little added benefit while exposing them to catheter complications, adverse drug effects, and antimicrobial resistance pressures.

The tripling of relapse rates is the trial’s central caution. Relapse in endocarditis — distinguished from reinfection by the recurrence of the same microorganism, typically within weeks to months of treatment completion — signals that bacteria persisted within the vegetation despite therapy. In a commentary accompanying the trial, Mary Philip and Gilbert Habib of La Timone Hospital in Marseille emphasize that the safety of the response-guided strategy will depend fundamentally on rigorous patient selection and close multidisciplinary follow-up.

The distinction between relapse and reinfection carries practical weight. Relapse typically involves the same organism and suggests inadequate eradication, whereas reinfection involves a new episode with a different microorganism. The tripling observed in POET II suggests that, for some patients, stopping antibiotics at the point of clinical stability leaves residual bacteria capable of re-emerging. Identifying which patients harbor such residual infection — and which have truly cleared it — is the core challenge for tailored therapy.

Philip and Habib frame POET II as a genuine conceptual advance beyond the oral-switch paradigm of the original POET trial. Where POET changed the route of delivery without altering total exposure, POET II directly tests whether total exposure can be reduced. The commentary authors suggest that the era of one-size-fits-all duration may be giving way to individualized approaches, in which the intensity and length of therapy are calibrated to each patient’s clinical trajectory, microbiological profile, and response to initial treatment.

The implications for clinical practice are likely to be gradual rather than immediate. Guidelines will need to weigh the benefit of shorter treatment — fewer catheter days, lower drug toxicity, reduced selection pressure for resistance, and shorter hospital stays — against the increased relapse risk. Patient selection will be paramount: individuals with virulent organisms, large vegetations, prosthetic material, or complicated courses may remain poor candidates for early cessation, while stable patients with uncomplicated disease and sensitive organisms may benefit most.

Close follow-up will be equally critical. Patients treated with a response-tailored strategy will require vigilant monitoring for early signs of relapse, including recurrent fever, new bacteremia, or hemodynamic deterioration, with ready access to repeat imaging and blood cultures. Multidisciplinary teams — cardiologists, infectious disease specialists, cardiac surgeons, and microbiologists — will need coordinated protocols to detect and manage relapse promptly. As Philip and Habib conclude, POET II marks a genuine shift in thinking, but its safe adoption will depend on the discipline of its implementation: the right patients, the right criteria, and the right follow-up.

Subject of Research: Infective Endocarditis

Article Title: Duration of antibiotic treatment for infective endocarditis: should we move towards tailored therapy?

Article References: Philip, M., & Habib, G. (2026). Duration of antibiotic treatment for infective endocarditis: should we move towards tailored therapy?. Nature Reviews Cardiology. https://doi.org/10.1038/s41569-026-01360-1

Image Credits: AI Generated

DOI: 10.1038/s41569-026-01360-1

Keywords: infective endocarditis, antibiotics, POET II trial, tailored therapy, cardiology, infectious diseases, Duration, antibiotic, treatment, infective, endocarditis, should

Fecal microbiota transplantation has consolidated itself as one of the most effective interventions in modern medicine for recurrent Clostridioides difficile infection, with success rates exceeding 90 percent in landmark trials. Increasingly, FMT is being explored for a wide spectrum of disorders linked to intestinal dysbiosis, including inflammatory, metabolic, and immune-mediated diseases. Yet unlike conventional pharmaceuticals composed of defined molecular entities, FMT involves the transfer of a complex and dynamic biological ecosystem whose composition remains only partially characterized. This intrinsic complexity complicates standardization, traceability, and quality control — fundamental requirements for the development of safe and scalable therapeutic products. Stool banks have emerged as essential infrastructures to centralize donor recruitment, ensure standardized screening, and support traceability, but their implementation remains heterogeneous across countries, reflecting differences in regulatory environments, technological capacity, and clinical practice.

The stringency of donor selection is the study’s first striking finding. The team, led by Lucas de Figueiredo Soveral and Carlos Rodrigo Zárate-Bladés at the Federal University of Santa Catarina, recruited 100 candidates through public calls between July and September 2023. Each volunteer completed a structured clinical screening questionnaire developed from a comparative analysis of major international guidelines, including the European consensus conference, the International Consensus Conference on stool banking, the Australian consensus statements, the Netherlands Working Group protocols, and a Brazilian FMT center at the Federal University of Minas Gerais. Exclusion criteria covered recent antibiotic use, chronic gastrointestinal diseases, metabolic or autoimmune disorders, recent infections, high-risk behaviors, and abnormal bowel habits, alongside questions about illicit drug use, chronic medication, and occupational exposure to hazardous substances. Only six candidates passed the clinical stage. After comprehensive laboratory screening — complete blood counts, serum electrolytes, renal and hepatic function markers, nutritional parameters, and serological tests for HIV, hepatitis A, B, and C, HTLV, cytomegalovirus, and Epstein-Barr virus — two more candidates were eliminated. One was excluded after multiplex PCR detected toxigenic C. difficile in the stool; another did not complete the process. Just four donors made it into the biobank, a four percent approval rate that mirrors the restrictive approval rates reported by international biobanking initiatives and underscores how demanding safe donor selection truly is.

Eligible donors received standardized collection kits with sterile containers and single-use stool collection devices, and samples were transported in insulated coolers so that no more than six hours elapsed between stool passage and laboratory processing. Under a laminar flow cabinet, fecal material was homogenized in sterile phosphate-buffered saline, filtered to remove particulate debris, aliquoted into 10 milliliter fractions, and stored at minus 80 degrees Celsius with continuous monitoring and full documentation for traceability. This operational framework, the authors argue, is particularly relevant for low- and middle-income countries, where microbiota-based therapies often face infrastructural and regulatory barriers and where workflows must be feasible within existing public healthcare systems.

Then came the genomic deep dive. The team extracted high-molecular-weight DNA from each donor’s fecal sample and performed shotgun metagenomic sequencing on Oxford Nanopore’s MinION platform, generating 7.09 gigabases of data across 5.44 million reads with an N50 of 2.55 kilobases. Resistance determinants were identified directly from sequencing reads using the Resistance Gene Identifier against the Comprehensive Antibiotic Resistance Database, retaining only Perfect and Strict hits to minimize false-positive assignments. The analysis revealed 180 different resistance-related gene entries across the four donors, with detection frequencies ranging from 87 genes in one sample to 137 in another. Only 58 entries were consistently detected in all samples, while 122 showed partial occurrence — a shared core resistome alongside marked interindividual variability. Among the consensus genes, just eleven were canonical antibiotic resistance genes, including APH(3′)-IIIa, CfxA2, CfxA3, ErmF, mefA, AlaS, and five tetracycline resistance determinants: tet(32), tet(40), tet(O), tet(Q), and tet(W).

The taxonomic associations of these dominant genes tell a coherent story about which gut bacteria serve as resistance reservoirs. tet(Q) was predominantly associated with Bacteroides fragilis, while tet(W) was mainly linked to Bifidobacterium longum. tet(O) was primarily attributed to Campylobacter jejuni, ErmF was also largely assigned to Bacteroides fragilis, and CfxA2 was associated with Prevotella intermedia. The proportional abundance of these genes varied dramatically between donors: in one sample, tet(Q) alone accounted for 34.3 percent of resistance gene abundance, while in another its dominance fell to 4.6 percent with increased contributions from tet(W) and the aminoglycoside-modifying gene ANT(6)-Ib. Across all donors, the resistome was dominated by aminoglycoside resistance (32.9 percent) and tetracycline resistance (28.9 percent), with multidrug resistance determinants adding another 19.3 percent. Functionally, resistance was mediated overwhelmingly through target alteration (58.2 percent) and target protection (26.8 percent), with enzymatic inactivation contributing 8.4 percent and efflux systems just 2.9 percent — indicating that resistance in these healthy guts is primarily about modifying or shielding antibiotic targets rather than degrading drugs or pumping them out.

The most technically consequential finding concerns genomic context. Because the presence of a resistance gene alone does not indicate its potential for transmission, the team assembled sequencing reads into contigs and screened them for plasmid associations and mobility-related features. Four ARG-containing contigs showed features compatible with potential mobility. In one donor, a tet(Q) gene sat on a circular contig classified as a plasmid with a score of 0.9949, containing a plasmid replication gene repA and an IS66 family transposase located roughly 1.1 kilobases downstream of the coding region. In another donor, an APH(3′)-IIIa gene occupied a circular plasmid contig carrying recombination proteins and a MOBV relaxase, while a separate tet(Q) gene lay about 5.4 kilobases upstream of a region containing multiple conjugative transfer genes — traO, traN, traM, traJ, traG, and traD — plus a relaxase. In a third donor, tet(Q) and ermF occurred together on a chromosomal contig with an IS30 family transposase immediately upstream of ermF, sharing architectural features with the CTnDOT family of Bacteroides conjugative transposons, which carries both determinants and contains mobilization regions. The authors emphasize that active horizontal gene transfer was beyond the scope of the study, but the genomic environments they documented are strikingly compatible with dissemination.

These findings carry real clinical weight. The concern is not hypothetical: in a seminal 2019 case, an extended-spectrum beta-lactamase-producing Escherichia coli was traced from donor material to an FMT recipient who developed bacteremia and died. Conversely, FMT has also been shown to promote sustained decolonization of multidrug-resistant organisms, replacing baseline ESBL-producing bacteria with susceptible strains. These contrasting outcomes suggest that the clinical implications of resistance genes in FMT depend on the broader donor-recipient context — the bacterial host, the genomic context, and especially the recipient’s clinical condition and anticipated antimicrobial exposure. The Brazilian team’s position is nuanced: metagenomic profiling should serve as a complementary layer of donor characterization and risk assessment rather than as a standalone exclusion criterion. When clinically relevant determinants are identified, decision makers could pursue phenotypic antimicrobial susceptibility testing or deeper genomic characterization, potentially drawing on existing World Health Organization guidance for surveillance of carbapenem-resistant Gram-negative bacteria in healthcare settings.

The study also acknowledges its limitations honestly. Each sequenced donor represented a single biological sample, so differences in gene occurrence should be interpreted as descriptive and exploratory; no inferential statistics were performed. ARG detection was based on sequence matching without phenotypic susceptibility testing or functional characterization, and the Nanopore platform’s read accuracy — between 79.6 and 84.7 percent — may influence sequence alignment and gene assignment. The screening workflow also lacked laboratory-based toxicological analyses for environmental contaminants, pharmaceutical residues, pesticides, and heavy metals, although exposure risks were assessed through the clinical questionnaire. Future studies with larger donor cohorts, complementary sequencing approaches, and longitudinal donor-recipient analyses integrating microbiome profiles with clinical outcomes will be needed to define the clinical relevance of resistome profiling.

Beyond donor screening, alternative FMT formulations may offer complementary biosafety strategies. Sterile fecal filtrates and defined microbial consortia — such as the oral microbiome therapeutic SER-109 — do not rely on transferring viable bacterial communities and may reduce some risks of introducing donor-derived organisms, with early clinical evidence suggesting retained therapeutic efficacy pending validation in larger settings. For now, the Florianópolis biobank stands as a proof of concept that rigorous conventional screening and metagenomic resistome analysis can coexist within a single operational framework, even in resource-constrained environments. As FMT expands toward increasingly vulnerable patient populations, the invisible resistance genes carried by every healthy donor — and the mobile elements that might shuttle them between gut bacteria — are becoming a central frontier in the safety of microbiota-based medicine.

Subject of Research: Identification of antibiotic resistance genes in fecal microbiota selected donors during the establishment of a biobank in the south of Brazil

Article Title: Identification of antibiotic resistance genes in fecal microbiota selected donors during the establishment of a biobank in the south of Brazil

Article References: Soveral, L. D. F., Holanda, L. R. D. L., Assunção, I. B. F., Gomes, L. G., de Souza, I. B., Rodrigues, G. D. S., Vanny, P. A., Bruna-Romero, O., Palmeiro, J. K., Scheffer, M. C., Sincero, T. C. M., & Zárate-Bladés, C. R. (2026). Identification of antibiotic resistance genes in fecal microbiota selected donors during the establishment of a biobank in the south of Brazil. Frontiers in Antibiotics, 5, Article 1905540. https://doi.org/10.3389/frabi.2026.1905540

Image Credits: AI Generated

DOI: 10.3389/frabi.2026.1905540

Keywords: Identification, antibiotic, resistance, genes, fecal, microbiota, selected, donors, during, establishment, biobank, south

The dominance of China, with 85 publications, and Italy, with 25, reflects complementary strengths rather than simple redundancy. Chinese groups have historically driven much of the fundamental materials chemistry of layered hydroxides, including refinements in co-precipitation, hydrothermal, and reconstruction methods that control layer charge density, interlayer spacing, and particle size, all of which govern how much antibiotic can be hosted and how quickly it escapes. Italian contributions, by contrast, have been closely associated with the biomedical translation of anionic clays, particularly in antitumoral and anti-inflammatory delivery, and that translational orientation naturally extends to antimicrobial applications where controlled release can reduce dosing frequency and limit the emergence of resistance at infection sites. The concentration of output in journals such as Applied Clay Science, the International Journal of Nanomedicine, and the International Journal of Biological Macromolecules illustrates the interdisciplinary position of the field: it sits at the intersection of clay mineralogy, nanomedicine, and macromolecular therapeutics, and authors must choose venues according to whether the novelty lies in the material synthesis or in the biological outcome.

The keyword co-occurrence findings, in which LDH, sustained release, and drug delivery emerge as central nodes, confirm that the community defines itself around the release kinetics problem rather than around any single antibiotic class. This is consistent with the underlying chemistry. The general formula of these materials, in which divalent and trivalent metal cations form positively charged hydroxide sheets balanced by interlayer anions and water, allows antibiotics bearing carboxylate, phosphate, or other anionic groups to be intercalated electrostatically. Once intercalated, release is governed by a combination of anion exchange with physiological counter-ions, partial dissolution of the layers, and diffusion through the particle periphery. Because the layers dissolve more readily in acidic media, the resulting carriers exhibit pronounced pH sensitivity, a property that is valuable at infected sites and in intracellular compartments such as phagolysosomes, where pH falls below that of blood and can be used to trigger preferential drug liberation. This same alkaline degradation behavior in gastric media, noted in the source literature, is a double-edged characteristic: it complicates oral delivery of acid-labile payloads yet can be exploited for gastric-responsive formulations.

The comparative framing against other carrier families provides useful context for interpreting why LDHs attract sustained attention despite their younger bibliography. Polyvinyl alcohol hydrogels are appreciated for biocompatibility and water processing but suffer from mechanical weakness and excessive hydrophilicity that accelerate burst release. Metal-organic frameworks offer exceptional internal surface area and tunable pore chemistry, yet concerns over long-term structural stability in aqueous biological environments, biodegradation products, and scalable cost remain active research questions. Mesoporous silica materials are the most clinically mature of the three comparators, but their typical pore dimensions constrain the size of molecules that can be loaded efficiently, and pore architecture influences release in ways that are difficult to tune independently. LDHs occupy a distinctive niche among these alternatives because their loading capacity is not limited by rigid pore windows; instead, the interlayer gallery can expand to accommodate bulky anionic species, and the layer charge can be adjusted through the divalent to trivalent cation ratio, giving formulators a direct handle on loading density and exchange kinetics. Their documented high anion exchange capacity, colloidal stability, and low toxicity in the reviewed literature further support this positioning.

The bibliometric emphasis on citation trends and thematic evolution also illuminates how the field has responded to the clinical backdrop of antimicrobial resistance. The 2022 GLASS report cited in the source article documents high resistance rates among common bacterial pathogens, and the parallel slowdown in the discovery of genuinely new antibiotic scaffolds has shifted attention toward maximizing the performance of existing drugs. Sustained-release delivery is one of the few strategies that improves the pharmacodynamic profile of an established antibiotic without requiring new chemistry at the molecular level. By flattening the sharp plasma spikes and troughs characteristic of immediate-release formulations, steady delivery maintains concentrations within the therapeutic window for longer periods, reduces the frequency of subinhibitory exposure that selects for resistant subpopulations, and improves patient adherence through fewer doses. In this sense, the bibliometric growth of LDH antibiotic delivery research can be read as a materials-science response to a pharmacological and epidemiological problem.

The methodological apparatus of the review itself deserves comment, because bibliometric analysis is increasingly used to map emerging biomedical materials fields and its limitations should be understood when interpreting the results. Restricting the corpus to English-language publications indexed in SCI-Expanded and ESCI introduces a selection bias toward established journals and anglophone or internationally publishing groups, which may undercount contributions from regions with strong domestic journals. The exclusion terms applied to remove degradation and adsorption studies, while scientifically justified, may also have removed hybrid papers that examined both adsorption and release. Nevertheless, the use of two complementary tools, VOSviewer for network visualization and the Bibliometrix package in R for descriptive and thematic statistics, strengthens the reliability of the mapping, since agreement between independent platforms on core findings such as country productivity and keyword clusters reduces the likelihood of software-specific artifacts. The reporting of total link strength as a measure of interaction intensity between nodes follows standard practice in science-mapping studies and allows readers to gauge not just the presence of a collaboration or co-occurrence but its relative weight within the network.

The identification of prominent authors, highly cited works, and funding sources within the 217-document corpus serves a practical function for newcomers to the field. Highly cited papers typically cluster around foundational demonstrations of antibiotic intercalation and release profiling, and tracing the citation flow from these works toward more recent publications reveals a thematic migration: early studies emphasized proof of concept for loading and release, while later work increasingly incorporates biological evaluation, including minimum inhibitory concentration assays, biofilm models, and cytocompatibility testing. The three-field plot analysis, which links countries, institutions, and keywords, exposes where interdisciplinary gaps persist, and the review’s framing of these gaps as opportunities for collaboration is consistent with the observation that no single discipline currently owns the problem. Materials chemists can optimize synthesis and interlayer architecture, microbiologists can define clinically relevant resistance and biofilm challenges, pharmacologists can model release and dosing, and toxicologists can establish biocompatibility thresholds, yet the bibliometric evidence suggests these communities have not fully converged.

The connection drawn between LDH drug delivery research and the Sustainable Development Goals reflects a broader trend in which bibliometric studies situate technical fields within global health priorities. Antimicrobial resistance is explicitly recognized in international frameworks as a threat to sustainable development, and delivery technologies that extend the useful life of existing antibiotics contribute to that agenda without demanding new molecular discovery. The emphasis on relevance to Sustainable Development Goals in the keyword and funding analysis indicates that funding agencies and journals increasingly reward work framed in these terms, which may in turn shape the direction of future publications toward applications with clear health-system relevance, such as wound dressings, implant coatings, and oral formulations for persistent infections.

Looking forward, the bibliometric evidence points toward several strategic directions that follow logically from the identified themes. First, the prominence of sustained release as a keyword suggests that quantitative release modeling, rather than qualitative demonstration, will be the differentiating contribution in coming years, since regulatory translation requires reproducible kinetics under physiologically relevant conditions. Second, the presence of gene therapy, biosensing, and ocular applications in the broader LDH literature signals that antimicrobial researchers may borrow formulation strategies from these adjacent domains, for example exploiting the positive surface charge that prolongs corneal residence to design mucoadhesive antimicrobial films. Third, the geographic concentration of output in two countries implies substantial untapped collaborative capacity, particularly in regions with high antimicrobial resistance burden but lower publication visibility in the indexed corpus, and international partnerships could align material development with the clinical epidemiology of resistance. Finally, the absence of prior bibliometric treatment of this field, which the review establishes as its central novelty, means that the 2025 dataset will serve as a baseline against which future updates can measure whether the field grows in volume, diversifies in geography, or shifts thematically from synthesis-oriented to clinically validated studies, and such longitudinal comparison is precisely the kind of insight that systematic bibliometric monitoring is designed to provide.

Subject of Research: Layered double hydroxides in sustained antibiotic delivery: a bibliometric review

Article Title: Layered double hydroxides in sustained antibiotic delivery: a bibliometric review

Article References: Verma, S. S., Varadavenkatesan, T., Selvaraj, R., & Vinayagam, R. (2026). Layered double hydroxides in sustained antibiotic delivery: a bibliometric review. Journal of Saudi Chemical Society, 30(5), Article 65. https://doi.org/10.1007/s44442-026-00120-7

Image Credits: AI Generated

DOI: 10.1007/s44442-026-00120-7

Keywords: Layered, double, hydroxides, sustained, antibiotic, delivery, bibliometric, review, scientific research

E. coli normally lives harmlessly in the intestinal tract, yet it is also the leading cause of many urinary tract infections. When the bacterium enters the urinary system, it can multiply in the bladder and, in some cases, travel to the kidneys or enter the bloodstream. Treatment traditionally relies on antibiotics selected according to local resistance patterns. However, repeated exposure to antibiotics creates evolutionary pressure: susceptible bacteria are eliminated, while variants carrying resistance mechanisms survive and reproduce. The Chennai study provides a detailed snapshot of how far that process has progressed in a population of urinary E. coli isolates examined in a diagnostic laboratory setting.

The investigators used the VITEK2 automated identification and antimicrobial susceptibility testing system, a platform widely used in clinical microbiology laboratories. The system determines whether bacterial growth is inhibited by specific antimicrobial agents and helps classify an isolate as susceptible, intermediate, or resistant according to laboratory standards. In this study, the antibiotic susceptibility card used was the GN-specific AST N-235 panel. The researchers then examined the results statistically and applied computational methods to reveal patterns that may be difficult to see when antibiotics are considered one at a time. This combination of routine laboratory testing, statistical analysis, and network science allowed the team to map resistance as an interconnected biological phenomenon.

The central result was striking: 70.5 percent of the isolates met the study’s definition of multidrug resistance. MDR generally refers to resistance to multiple antimicrobial categories, meaning that the bacterium is no longer vulnerable to several standard treatment options. The most prominent resistance was reported against nalidixic acid, ampicillin, and ticarcillin. Nalidixic acid is an older quinolone, while ampicillin and ticarcillin belong to the β-lactam family, a broad group that includes many drugs used against urinary and other bacterial infections. Resistance to these agents can reflect both long-standing antibiotic selection and the spread of bacterial lineages carrying multiple resistance genes.

The study also detected extended-spectrum β-lactamase production in 35.3 percent of the isolates. ESBLs are enzymes that break down a wide range of β-lactam antibiotics, including many penicillin and cephalosporin drugs. Their presence is clinically important because ESBL-producing bacteria can remain resistant even when a physician selects an antibiotic that would ordinarily be effective against E. coli. The genes encoding these enzymes are often carried on plasmids, small DNA molecules that can move between bacteria. This mobility enables resistance traits to spread not only through bacterial reproduction but also through horizontal gene transfer, allowing unrelated organisms to acquire similar defences.

To explore these relationships, the researchers constructed a co-resistance network. In this model, each node represented an antibiotic, while the connections between nodes reflected the number of isolates simultaneously resistant to both drugs. A stronger connection indicated that resistance to two antibiotics frequently appeared in the same bacterial isolates. The resulting network was concentrated around nalidixic acid, ampicillin, and ticarcillin, suggesting that resistance to these drugs was not occurring independently. Instead, it may have been linked by shared genetic elements, common exposure to antibiotic classes, or the expansion of bacterial clones carrying several resistance determinants.

Network analysis offers a different perspective from a conventional resistance table. A table can show that a bacterium is resistant to one drug at a particular frequency, but it does not necessarily reveal which resistances travel together. When several antibiotic resistances are tightly connected, prescribing one drug may indirectly select for bacteria resistant to others if the same genetic package or bacterial lineage carries multiple traits. These patterns can help microbiologists and public-health teams identify priority combinations for surveillance. They may also support antibiotic stewardship by showing where unnecessary or poorly targeted prescribing could reinforce a broader resistance network.

The researchers further investigated whether age was associated with antimicrobial resistance using logistic regression, a statistical method that estimates how a potential factor changes the odds of an outcome. Their analysis indicated a positive relationship between patient age and resistance to fluoroquinolone antibiotics. Older patients may have greater cumulative exposure to antibiotics, more frequent healthcare contact, recurrent urinary infections, or medical conditions that increase the likelihood of colonisation by resistant organisms. The study also reported that females accounted for a higher proportion of cases, with 75.5 percent reported in the analysis. This is consistent with the well-established observation that women experience UTIs more often, partly because of anatomical factors that facilitate the movement of intestinal bacteria into the urinary tract.

The findings carry implications beyond a single laboratory or city. They reinforce the need for urine cultures and susceptibility testing when infections are recurrent, severe, or unlikely to respond to first-line treatment. They also underline the importance of antimicrobial stewardship programmes, which aim to ensure that antibiotics are prescribed only when necessary, at the correct dose, for the appropriate duration, and with the narrowest effective spectrum. Surveillance systems can track changing resistance patterns, while infection-control measures can reduce the spread of resistant strains in healthcare environments. The authors argue that addressing MDR urinary infections will require coordinated action involving clinicians, laboratories, public-health authorities, and international monitoring networks.

Because the investigation was conducted at one diagnostic laboratory and covered a six-month period, its results may not represent every patient or healthcare setting in India. Nevertheless, the large number of isolates and the integration of laboratory data with co-resistance network analysis provide a valuable warning. E. coli is adapting to the antibiotic environment created by modern medicine, and the appearance of resistance to several drugs within the same isolates narrows the margin for safe and effective treatment. The study’s message is clear: urinary infections cannot be managed sustainably through prescribing habits alone. Continued resistance surveillance, better diagnostic testing, responsible antibiotic use, and collaboration across regions will be essential to prevent common bacterial infections from becoming increasingly difficult to control.

Subject of Research: Multidrug-resistant Escherichia coli isolates causing urinary tract infections, antimicrobial resistance patterns, ESBL production, co-resistance networks, and age-associated resistance.

Article Title: Prevalence and co-resistance network analysis of multidrug-resistant Escherichia coli isolates from urinary tract infections, a cross-sectional study

Article References: Srijith, L., Sivakumar, V., Parameswaran, R. et al. “Prevalence and co-resistance network analysis of multidrug-resistant Escherichia coli isolates from urinary tract infections, a cross-sectional study.” BMC Infectious Diseases (2026).

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14213-6

Keywords: Multidrug-resistant Escherichia coli, urinary tract infections, antimicrobial resistance, extended-spectrum β-lactamase, ESBL, co-resistance network, fluoroquinolone resistance, antibiotic stewardship, logistic regression.