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Nasopharyngeal Carriage Rate, Risk Factors, and Co-Resistance Patterns of Methicillin-Resistant Staphylococcus aureus in Ethiopia: Systematic Review and Meta-Analysis.

Methicillin-resistant Staphylococcus aureus (MRSA) nasopharyngeal carriage is a major global health concern linked to severe infections and transmission. However, comprehensive evidence on the burden of MRSA carriage, antimicrobial resistance, and associated risk factors in Ethiopia remains limited. This study aimed to estimate pooled prevalence, resistance pattern, and determinants of nasopharyngeal MRSA carriage. PubMed, ScienceDirect, Scopus, Web of Science, Google Scholar, and gray literature were searched for cross-sectional studies published between January 2015 and December 2025. Two groups of reviewers screened studies based on predefined criteria. The risk of bias was assessed using the Joanna Briggs Institute tool. Pooled prevalence and resistance proportions were estimated using a random-effects model, and pooled odds ratios (ORs) were calculated using the Mantel-Haenszel method. Heterogeneity and publication bias were assessed, and a sensitivity analysis was conducted. A total of 1040 records were identified, and 20 studies (6869 participants) were included. The pooled carriage prevalence was 7.3% (95% CI, 5.0-10.8), with substantial heterogeneity (I2 = 95.5%). Resistance was highest to tetracycline (55.75%) and lowest to clindamycin (12.66%). Increased odds of carriage were associated with prior hospitalization (OR, 3.49) and antibiotic use (OR, 2.35). Inconsistent variable coding across included studies limited the inclusion of other potential risk factors. Evidence of publication bias was detected, suggesting that the pooled prevalence should be interpreted with appropriate caution. The findings indicate a considerable burden of MRSA and highlight the need for strengthened antimicrobial stewardship, improved surveillance, and targeted prevention efforts in higher-risk populations. This review was registered in PROSPERO (CRD420251047192).

Ethiopia

Fracture-related infection following open forefoot fractures caused by dropped objects.

INTRODUCTION: This study evaluated the rate of fracture-related infection (FRI) of open forefoot fractures caused by dropped objects, and examined associations of treatment characteristics, including intravenous and oral antibiotics and operative debridement, with FRI. METHODS: Patients aged 18-80 years who sustained an open metatarsal or phalanx fracture caused by a dropped object between January 2021 and June 2024 were retrospectively identified from two Level 1 trauma centers. The primary outcome was FRI, determined based on the FRI consensus criteria. FRI rates were compared between those who underwent irrigation and debridement (I&D) at bedside versus in the operating room, and between those who received oral versus intravenous (IV) antibiotics. Patient characteristics were also analyzed to determine host factors associated with FRI. RESULTS: A total of 86 patients (median age 41 years [IQR: 29-56], 58% male) were included. Eighty-five patients (99%) received antibiotics, 31 (36%) of whom received intravenous antibiotics. Sixty-six patients (77%) received an I&D at presentation, 57 (66%) at bedside and 9 (10%) in the operating room. Thirteen patients (15%, 95% CI: 8.3%-24%) developed FRI. No significant difference in FRI rate was found between patients who underwent I&D at bedside versus in the operating room (12% versus 11%, p > 0.99). Among patients who did not undergo I&D in the operating room, no significant difference in FRI rate was found between patients who received oral versus IV antibiotics (17% versus 13%, p = 0.74). Insulin-dependent diabetes was associated with an increased risk of FRI (60% versus 12%, p = 0.02). CONCLUSIONS: In this cohort, one in seven patients developed FRI. No statistically significant differences in FRI rates were observed by I&D setting (bedside versus operative) or antibiotic route (oral versus IV), including in a subgroup analysis excluding patients treated with operating room I&D. These findings are limited by sample size and potential treatment selection bias and should not be interpreted as evidence of equivalence. Management should be individualized based on clinical judgement, resource availability, and patient factors. These findings can help guide the management protocols for "dropped objects" open forefoot fractures presenting to urgent care and the emergency department. LEVEL OF EVIDENCE: Therapeutic Level III.

Humans

Characteristics of children with ureteroceles presenting for urological evaluation in the modern medical era.

INTRODUCTION: Historically, children with ureteroceles presented symptomatically and were managed surgically. It is unclear if this changed in the modern medical era of prenatal imaging and shared decision making. We aimed to describe the presentation and management of ureteroceles during initial urological evaluation of children in the era of widespread prenatal ultrasonography. PATIENTS AND METHODS: We retrospectively reviewed records of children (<18 years old [yo]) initially evaluated at our center with a ureterocele (2011-2020). We analyzed demographics, renal anatomy, initial presentation for evaluation, and initial management with non-parametric statistics. Febrile urinary tract infections (fUTIs, &#x2265; 38 &#xb0;C) were classified as 1) urosepsis (positive urine culture admitted to pediatric intensive care), 2) documented (positive urine culture) or 3) family-reported. RESULTS: We identified 188 children (65% female). Median age at presentation was 1.2 months old (mo) (IQR 18 days-4.4 mo). Antenatally-detected congenital anomalies of the kidney and urinary tract (aCAKUT) were noted in 143 (76%) children with a confirmed postnatal diagnosis of ureterocele. Overall, 129/188 (69%) children presented without symptoms and 59 (31%) presented with symptoms. fUTI was the most common symptomatic presentation (46/188, 24%): urosepsis (6 children), documented (30), and family-reported (10). Children with aCAKUT presented earlier than those without aCAKUT (27 days vs. 1.6 yo, p < 0.0001). They were also less likely to present with symptoms (11% vs. 96%, p < 0.0001), including fUTIs (7% vs. 78%, p < 0.0001). In total, 108 children (57%) were initially managed with transurethral incision, 73 (39%) were observed, and 7 (4%) had reconstructive surgery. Asymptomatic children with aCAKUT (42%) and symptomatic children without aCAKUT (37%) were more likely to be observed than symptomatic children with aCAKUT (7%, p = 0.02). Among 143 children with aCAKUT, those on antibiotic prophylaxis were less likely to present with a history of a fUTI compared to those not on prophylaxis (4/106 vs. 6/37, 4% vs. 16%, p = 0.02). COMMENT: We present a large observational study describing clinical and anatomical characteristics of children presenting with ureteroceles in a medical era of ubiquitous prenatal ultrasonography. Our retrospective study was limited by incomplete documentation of all antenatal ultrasonography and adherence with antibiotic prophylaxis. Long-term clinical outcomes will be the focus of future work. CONCLUSION: In contrast to historical cohorts, most children presented to urologists with asymptomatic ureteroceles diagnosed with aCAKUT. Most children without aCAKUT presented with a fUTI. Overall, 39% of children were initially observed, indicating an increased use of observation in the modern medical era.

Humans

Genetic mutations driving ciprofloxacin resistance in laboratory-evolved Salmonella Typhimurium.

Ciprofloxacin resistance in Salmonella Typhimurium is a significant public health concern, and the mechanisms by which the resistance evolves are poorly defined. Here, by serial passaging under antibiotic selection, we isolated ciprofloxacin-resistant S. Typhimurium mutants and subjected them to whole-genome sequencing to reveal the major mutations associated with resistance. The Low CipR mutant acquired four chromosomal mutations in ramR, icdA, lipB, and gyrA, and the High CipR mutant gained additional mutations in gyrB, yaiC, and corA. Functional characterization determined that mutations in ramR resulted in efflux pump upregulation, while disruptions in the TCA cycle caused by mutations in icdA and lipB led to metabolic alterations. These changes indirectly enhanced resistance by increasing the expression of the global regulator MarA and reducing OmpF-dependent membrane permeability. Despite the observation of the G105A substitution in GyrA, enzymatic assays confirmed the failure to support resistance to ciprofloxacin, possibly because the structural alteration remained minimal. GyrB488-489dup was associated with maintained supercoiling under ciprofloxacin and enhanced fluoroquinolone resistance, suggesting a major role in resistance evolution. Other mutations in yaiC impaired biofilm and, in corA, intracellular accumulation of magnesium, possibly stabilizing the bacterial cell envelope under antibiotic pressure. The findings provide novel explanations for the multifaceted mechanisms leading to ciprofloxacin resistance in Salmonella and suggest targets to combat antimicrobial resistance.IMPORTANCEAntibiotic resistance in Salmonella Typhimurium is an increasing public health concern, yet the genetic changes that allow bacteria to become resistant are not fully understood. In this study, we evolved ciprofloxacin-resistant Salmonella in the laboratory and identified the mutations that arise during resistance development. We found that resistance does not result from a single change but from multiple adaptations affecting drug efflux, metabolism, and the antibiotic target. Some mutations increased the activity of pumps that remove antibiotics from the cell, while others altered bacterial metabolism and reduced membrane permeability, making it harder for the drug to enter. A duplication in the DNA gyrase subunit GyrB played a particularly important role in maintaining DNA function under antibiotic stress. Together, these results reveal how diverse genetic changes cooperate to generate ciprofloxacin resistance and provide insights that may help guide strategies to combat drug-resistant Salmonella infections.

DNA gyrase

Clinical Outcomes and Genomic Epidemiology of Multidrug-Resistant Methicillin-Resistant Staphylococcus aureus Keratitis.

PURPOSE: To characterize the clinical features, management, antimicrobial resistance patterns, and genomic epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) keratitis at two North American centers. DESIGN: Retrospective interventional case series combined with laboratory investigation PARTICIPANTS: Seventy eyes of 67 patients presenting laboratory-confirmed MRSA keratitis were included METHODS: We performed a multicenter retrospective case series of patients with culture-proven MRSA keratitis treated between 2005 and 2022. Demographic and clinical data were collected. Antimicrobial susceptibility testing was conducted, and multidrug resistance (MDR) was defined as resistance to &#x2265;3 antibiotic classes. A subset of isolates underwent whole-genome sequencing with core genome multilocus sequence typing. Vancomycin susceptibility, heteroresistance screening, and tolerance testing were performed on available isolates. MAIN OUTCOME MEASURES: Antimicrobial susceptibility and multidrug resistance rates, vancomycin phenotypic profiles, MRSA genotypic distribution, and final best-corrected visual acuity RESULTS: Median age was 63.5 years, and 61.4% were female. Ocular surface disease (67.7%) and prior ocular surgery (65.2%) were common. Only 25.4% had significant healthcare exposure in the preceding year. Most isolates (85.7%) were MDR. Fluoroquinolone susceptibility was low (moxifloxacin 19.7%). All isolates were susceptible to vancomycin (MIC&#x2089;&#x2080; 2 &#xb5;g/mL), and no vancomycin-intermediate, heteroresistant, or tolerant phenotypes were identified. Whole genome sequencing (n = 41) demonstrated predominance of clonal complexes 5 (68.3%) and 8 (29.2%). Visual outcomes were poor, with most patients (85.2%) having a final visual acuity worse than 20/60 among those with follow-up. CONCLUSIONS: MRSA keratitis is associated with high rates of multidrug resistance and poor visual outcomes despite guideline-based therapy. Infections were predominantly caused by CC5 MDR strains despite limited recent healthcare exposure. These findings highlight the persistence of highly resistant MRSA lineages in community-associated corneal infection and underscore the need for ongoing antimicrobial surveillance and optimized treatment strategies.

Humans

Dynamics and virulence of Enterobacteriaceae reservoirs harboring blaCTX-M group 1 in community wastewater.

UNLABELLED: Extended-spectrum beta-lactamase (ESBL)-producing bacteria are ubiquitous and can cause serious infections. Here, we examined untreated community wastewater influent as a reservoir for blaCTX-M group 1 organisms and their virulence potential. Raw influent samples (n = 268) were collected from four wastewater treatment plants (WWTPs) representing dense urban populations. We observed that blaCTX-M group 1 levels were high at all WWTPs and only ~1-2 log10 lower and not correlated to common human-specific microbiome fecal markers, Lachno3 and HF183, indicating a lack of connection to human fecal inputs. Concentrations of blaCTX-M group 1 genes and markers for presumptive host organisms Escherichia coli and Klebsiella pneumoniae were influenced by travel time and season. Amplicon sequencing revealed high diversity of blaCTX-M group 1-9 genes, with 63% belonging to group 1. Selective culture and 16S rRNA gene sequencing showed blaCTX-M group 1 isolates were 26% E. coli, 26% K. pneumoniae, 40% other Enterobacteriaceae, and 8% Aeromonas. Overall, E. coli averaged 3.6E7 cells/L, with 3% of all E. coli found to contain blaCTX-M group 1. Whole-genome sequencing of blaCTX-M group 1 E. coli from wastewater revealed resistance and virulence gene profiles similar to clinical isolates and distinct from other wastewater ESBL-resistant and non-resistant E. coli. Interpretation of wastewater data needs to consider both the existence of environmental reservoirs that contain potentially pathogenic organisms and the strong influence the dynamics of the conveyance system can have on final concentrations measured at the WWTP. IMPORTANCE: The CTX-M enzyme family is highly abundant in nosocomial, community, and environmental settings and is leading to treatment of infections with carbapenem antibiotics, a last-line therapeutic option. The progressive increase of the clinically relevant blaCTX-M group 1 resistance genes in the human population warrants investigation, particularly to understand the establishment and dynamics of environmental reservoirs. This study utilized molecular and culture methods to gain insight into the possible origin, abundance, and dynamics of blaCTX-M group 1 genes in untreated wastewater influent samples. We found extremely high levels of these genes, with Escherichia coli as a major host organism that closely resembled clinical strains, suggesting they are seeded and propagate in sewer pipe systems. The significance of our research is in developing approaches to monitor antimicrobial resistance reservoirs in community wastewater, which could shed light on global burdens and potential transmission cycles and indicate increasing inputs of clinically relevant strains originating from human populations.

E. coli

Emphysematous pyelonephritis in children: Lessons from a case report and systematic review.

BACKGROUND: Emphysematous pyelonephritis (EPN) is a rare, life-threatening gas-producing renal infection. Literature on pediatric EPN remains scarce. OBJECTIVE: To describe a case of pediatric EPN and systematically review the data on clinical presentations, diagnostic modalities, management strategies, and prognosis in pediatric emphysematous pyelonephritis. METHODS: A comprehensive search in PubMed, Embase and Web of Science using defined search terms was done, along with the Joanna Briggs Institute (JBI) critical appraisal checklist for quality assessment. RESULTS: Of 100 records, 20 studies (n = 21) were included in the review. The median (IQR) age of presentation was 48 (8-138) months. The major risk factor was reflux/obstructive nephropathy (52.3 %), and E. coli was the common organism. Management included antibiotics (47.6 %), minimally invasive procedures (33.3 %), or nephrectomy (19 %). We additionally report an adolescent girl with Type 1 diabetes mellitus and class 3A right-sided EPN. She improved with antibiotics and percutaneous nephrostomy (PCN) insertion. CONCLUSION: Obstructive or reflux nephropathy is a major risk factor for pediatric EPN. Antibiotics are the mainstay for treatment with supportive management. Refractory cases may require percutaneous drainage or partial/total nephrectomy.

Humans

Intravesical mitomycin-C administered immediately before transurethral resection of bladder tumor in non-muscle-invasive bladder cancer: Clinical outcomes and molecular predictors from over 3 years of extended follow-up in a phase II trial.

PURPOSE: To evaluate the long-term outcomes and molecular correlates of response after immediate preoperative intravesical chemotherapy (IPeIC) with mitomycin-C (MMC) in patients with non-muscle-invasive bladder cancer (NMIBC). MATERIALS AND METHODS: In this single-center, open-label, randomized phase II trial, 33 patients received two split doses of IPeIC/MMC (40 mg/20 mL), whereas 38 patients underwent transurethral resection of bladder tumor (TURBT) alone. The primary endpoint was 3-year recurrence-free survival (RFS), and secondary endpoints included progression-free survival (PFS). Exploratory RNA sequencing was performed on IPeIC-treated patients (three with recurrence, 25 without) using a Monte Carlo-based resampling strategy. RESULTS: The median follow-up durations were comparable between the intervention (60.0 months) and control arms (60.4 months). IPeIC/MMC reduced recurrence risk by 76.8% versus TURBT alone (p=0.024), yielding a 3-year RFS rate of 90.7% versus 78.6%. On multivariable analysis, IPeIC/MMC independently improved RFS (hazard ratio [HR] 0.266, p=0.044). IPeIC was associated with superior PFS, with 3-year and 5-year rates of 100% versus 92.1% and 85.8%, respectively, in the controls (HR 0.078, p=0.014). Exploratory transcriptomics identified low Glutathione S-transferase Mu 1 (GSTM1) expression as the factor most strongly associated with recurrence. CONCLUSIONS: IPeIC/MMC is associated with improved long-term oncological outcomes compared with TURBT alone and represents a safe prophylactic option for patients with NMIBC who are unable to receive standard immediate postoperative intravesical chemotherapy because of safety concerns or practical constraints. The GSTM1 findings are hypothesis-generating and support future biomarker-driven validation studies.

Aged

Fourteen-Day Amoxicillin- or Tetracycline-Containing Bismuth Quadruple Therapy versus 14-Day Metronidazole-Based Triple Therapy as the Treatment for Clarithromycin-Resistant Helicobacter pylori Infection: A Multicenter Randomized Controlled Trial.

BACKGROUND/AIMS: Combination therapy comprising a proton pump inhibitor (PPI), amoxicillin, and metronidazole (PAM) is used to treat clarithromycin-resistant Helicobacter pylori in the Republic of Korea, but eradication rates are decreasing due to an increasing incidence of clarithromycin resistance. We compared PAM, bismuth compounds plus PAM (PAM-B), and the combination of PPI, bismuth compounds, metronidazole, and tetracycline (PBMT) to determine whether PAM-B can achieve an eradication rate higher than that of PAM and comparable to that of PBMT. METHODS: This prospective multicenter study enrolled patients with clarithromycin-resistant H. pylori infections in the Busan and Gyeongsangnam-do of the Republic of Korea between December 2022 and February 2024. RESULTS: In the intention-to-treat (ITT) analysis, the eradication rate was significantly lower in the PAM group (68.2%) than in the PAM-B group (84.8%, p=0.024), whereas the difference from the PBMT group (81.8%) was not significant (p=0.070). The rate remained lowest in the PAM group (75.4%) in the per-protocol (PP) analysis (PAM-B, 96.5%, p=0.001; PBMT, 94.6%, p=0.004). Eradication rates were comparable between the PAM-B and PBMT groups in both the ITT (p=0.640) and PP analyses (p=0.633). Nausea and vomiting were significantly less frequent in the PAM-B group than in the PBMT group (6.8% vs 25.0%; p=0.007). Severe adverse events were rare, and all symptoms resolved after treatment discontinuation. CONCLUSIONS: PAM-B yielded eradication rates higher than those of PAM and comparable to those of PBMT, with no significant increase in the incidence of adverse events, suggesting the potential of PAM-B as a first-line treatment for clarithromycin-resistant H. pylori infection. Further large-scale studies are needed to validate these results. Registered retrospectively with the Clinical Research Information Service (CRIS; KCT0012265).

Humans

Empirical Meropenem Versus Piperacillin/Tazobactam for Critically Ill Adults With Sepsis: Feasibility of a Randomised Trial.

BACKGROUND: Meropenem and piperacillin/tazobactam are commonly used empirical antibiotics in critically ill adults with sepsis, but whether one is superior to the other is uncertain. METHODS: The Empirical Meropenem versus Piperacillin/Tazobactam for Adult Patients with Sepsis (EMPRESS) trial is an ongoing investigator-initiated, randomised, open-label, adaptive clinical trial with an integrated feasibility phase comparing empirical treatment with meropenem versus piperacillin/tazobactam in critically ill adults with sepsis. The integrated feasibility phase enrolled 200 participants across 10 intensive care units (ICUs) in Denmark between 28 June and 12 December 2025. Five pre-specified feasibility criteria were evaluated; if all feasibility criteria were met, the trial would proceed unaltered, whereas failure to meet one or more criteria would require intervention and re-evaluation. RESULTS: We randomised 200 of 284 screened patients (70.4%). The median age was 70&#x2009;years (interquartile range (IQR): 60-77), 65.5% were males. At randomisation, 80.0% received vasopressors or inotropes, and 43.5% were on invasive mechanical ventilation. Four of five pre-specified feasibility criteria were met: time to completion of the feasibility phase (5.5&#x2009;months vs. threshold <&#x2009;12.0&#x2009;months), recruitment proportion (70.4% vs. threshold &#x2265;&#x2009;50.0%), proportion of participants without consent to the continued collection of data (2.5% vs. threshold <&#x2009;5.0%) and protocol adherence (81.0% vs. threshold &#x2265;&#x2009;75.0%). The proportion of participants with timely primary outcome data availability (30-day mortality) within 45&#x2009;days was 85.5% and below the pre-specified threshold of &#x2265;&#x2009;95.0%. The proportions were low in the first 3&#x2009;months (33.3%, 22.2% and 30.8%, respectively), increasing to 95.8% in the last month of the feasibility phase. All-cause mortality at 30&#x2009;days was 30.5%, and specific serious adverse reactions occurred in 4.0% of participants. CONCLUSIONS: In this integrated feasibility evaluation of the EMPRESS trial comparing empirical meropenem versus piperacillin/tazobactam in critically ill adults with sepsis, four of five pre-specified feasibility criteria were met. The unmet criterion, timely primary outcome data availability, improved substantially during the feasibility phase. We consider the trial feasible and will proceed without modifications. EDITORIAL COMMENT: This feasibility study assessed recruitment, randomised allocation and data collection for the multicentre EMPRESS trial. For adaptive trials on trial platforms, careful interim checking of trial design functions is an important and necessary process. TRIAL REGISTRATION: Clinical Trials Information System EUCT number: 2023-509703-33-00; ClinicalTrials.gov identifier: NCT06184659; Universal Trial Number: U1111-1301-6379.

Humans

The spatial and temporal distribution of Staphylococcus aureus along a tropical Hawaiian watershed.

Staphylococcus aureus is a leading cause of community-acquired skin and soft-tissue infections worldwide. One major route of exposure is recreating in marine waters, but knowledge is limited regarding the drivers of S. aureus in surface waters that discharge into marine environments. This study explores spatial and temporal distributions of S. aureus, including antimicrobial-resistant and virulence genes, using both culture-dependent and molecular techniques across a tropical Hawaiian watershed with a gradient of human influence. Negative binomial generalized linear mixed models revealed that the interaction between spatial and temporal factors was the strongest predictor of S. aureus and associated genes. Cultured S. aureus was highest at mid-watershed sites in summer, which included a popular swimming hole, suggesting human shedding as a significant source. Molecular detection of S. aureus (femA gene) yielded concentrations two orders of magnitude higher than cultured concentrations and peaked at estuarine sites with the greatest nutrients and water residence times. In the winter at upstream sites with no public access, staphylococci antibiotic-resistant (mecA) and S. aureus virulence gene (etb) were elevated, indicating highly pathogenic S. aureus strains in surface waters may originate from zoonotic sources. Our findings indicate that human and zoonotic sources contribute antibiotic-resistant and virulent S. aureus to watersheds, with streams facilitating environmental transmission to marine waters. This watershed-scale assessment enables the prediction of spatial and temporal conditions associated with elevated S. aureus concentrations, thereby reducing exposure and infections.

Staphylococcus aureus

Strategy for enhanced production of A40926B0 in Nonomuraea gerenzanensis using an efficient CRISPR/AsCas12f1 system.

The global emergence of vancomycin-resistant Gram-positive pathogens underscores the urgent need for efficient production of novel lipoglycopeptide antibiotics. Dalbavancin, a last-resort therapeutic agent, relies on its key biosynthetic precursor A40926B0, whose industrial manufacture is severely limited by the low yield of wild-type Nonomuraea gerenzanensis and inefficient genetic tools for this rare actinomycete. Here, we developed a high-efficiency CRISPR/AsCas12f1 genome editing system and applied systematic metabolic engineering to boost A40926B0 biosynthesis. First, conjugation conditions were optimized to elevate the transfer efficiency in N. gerenzanensis D11. The hypercompact AsCas12f1 nuclease showed markedly lower cytotoxicity than SpCas9 and enabled 100% gene deletion efficiency with preferred PAMs (TTTG, CTTG, GTTG). Second, we strengthened the shikimate pathway via multiple genetic strategies: overexpressing feedback-resistant DAHP synthase (aroG fbr ) and chorismate mutase/prephenate dehydrogenase (tyrA fbr ), as well as knocking out pheA. This manipulation blocks the phenylalanine synthetic branch and redirects metabolic flux toward the l-tyrosine branch. Third, we engineered the branched-chain fatty acid (BCFA) pathway via promoter replacement of bkdA2B2C2, LipAB, fabF and deletion of acdH to enhance isododecanoyl side-chain supply. The combinatorial engineering yielded strain B-13, which produced 1740&#x202f;mg/L A40926B0 in shake flasks. Finally, 50-L fed-batch fermentation with continuous maltodextrin feeding further increased the titer to 1817&#x202f;mg/L, the highest reported titer to date. This work establishes a robust CRISPR editing tool for N. gerenzanensis and provides valuable engineering references for precursor-oriented strain improvement targeting lipoglycopeptide antibiotics, offering insights for the industrial scale production of A40926B0.

A40926B0

Cefoxitin versus cefotaxime as empirical treatment of spontaneous bacterial peritonitis in liver cirrhotic patients: randomized controlled clinical trial.

BACKGROUND: Spontaneous bacterial peritonitis (SBP) is a severe complication of cirrhosis requiring immediate empirical antibiotic therapy. Third-generation cephalosporins are the traditional agents of choice; however, increasing clinical failure rates necessitate the evaluation of alternative antibiotics to ensure optimal therapeutic outcomes. The aim was to investigate the efficacy of cefoxitin versus cefotaxime for SBP treatment. METHODS: A randomized clinical trial was conducted on 140 cirrhotic patients with community-acquired SBP at Al-Rajhy Liver University Hospital, Assiut, Egypt. Patients were randomized to receive either cefotaxime (n&#x200a;=&#x200a;70) or cefoxitin (n&#x200a;=&#x200a;70), 2&#x2005;g every 8&#x2005;h for 5&#x2005;days. Polymorphonuclear neutrophil (PMN) counts were measured upon admission, on Day 2 and on Day 5. Clinical response rates at Days 2 and 5, development of hepatorenal syndrome, length of stay and mortality were assessed. RESULTS: According to intention-to-treat analysis, clinical response rates at Day 2 were 74.2% in the cefotaxime group and 80% in the cefoxitin group, while at Day 5, they were 71.4% and 74.3%, respectively (P&#x200a;=&#x200a;0.704). The PMN counts at Days 0, 2 and 5 showed no significant differences between the cefotaxime and cefoxitin groups (P&#x200a;=&#x200a;0.889, 0.909 and 0.360, respectively). The incidence of hepatorenal syndrome was 7.1% in the cefotaxime group compared with 8.6% in the cefoxitin group (P&#x200a;=&#x200a;0.753), and mortality was 15.7% and 12.9%, respectively (P&#x200a;=&#x200a;0.629). CONCLUSIONS: Cefoxitin showed comparable effectiveness to cefotaxime but may be utilized in selected clinically stable SBP patients.

Humans

Timing of carbetocin administration in vaginal deliveries: a double-blind, randomized controlled trial.

OBJECTIVES: This study aimed to compare the efficacy of administering carbetocin before vs. after placental delivery in preventing postpartum hemorrhage (PPH) in low-risk vaginal deliveries. METHODS: The randomized controlled trial was conducted at Kartal City Hospital, Istanbul, Turkey. A total of 160 primiparous women with uncomplicated pregnancies who underwent vaginal delivery were enrolled. Participants were randomly assigned to receive 100&#x202f;&#x3bc;g of carbetocin either before or after placental delivery. The primary outcome was the incidence of PPH. Secondary outcomes included the need for additional uterotonics, manual removal of the placenta with consequent antibiotic administration, blood transfusions, maternal adverse events, and changes in hemoglobin levels at baseline and 24&#x202f;h postpartum. RESULTS: The incidence of PPH was significantly lower in the carbetocin-before group than in the carbetocin-after group (p=0.015). The carbetocin-before group had a significantly lower mean hemoglobin drop compared to the carbetocin-after group (p<0.001). The need for additional uterotonics was significantly higher in the carbetocin-after group (p<0.001). Manual placenta removal and the need for antibiotics were more frequent in the carbetocin-before group (p=0.017). No significant differences in adverse maternal events were observed between the groups. CONCLUSIONS: Administering carbetocin before placental delivery significantly reduces the incidence of PPH, blood loss, and the need for additional uterotonics. However, the increased rate of manual placenta removal necessitates individualized risk-benefit assessment; pre-placental administration may be most advantageous in women at elevated risk for PPH, in whom the hemorrhagic benefit outweighs the risks associated with manual extraction.

Humans

Integrated proteomic and acetylomic analyses reveal the metabolic reprogramming associated with increased tylosin-equivalent concentration in Streptomyces xinghaiensis sf106-B1.

Deciphering the metabolic basis of high-yield antibiotic production in Streptomyces is crucial for strain optimization. Atmospheric and room-temperature plasma (ARTP) mutagenesis of Streptomyces xinghaiensis sf106 generated a mutant with a 30% increase in tylosin-equivalent concentration (&#x3bc;g/mL). 4D-FastDIA quantitative proteomics identified 279 differentially abundant proteins enriched in the Type I polyketide synthase (PKS) pathway, with increased abundance of key macrolide-biosynthesis-related proteins. Lysine-acetylome profiling identified 1152 differentially abundant acetylation sites and revealed altered acetylation of enzymes involved in fatty acid metabolism and the tricarboxylic acid (TCA) cycle, suggesting adjustments in central metabolism associated with acyl-CoA precursor availability and energy generation. Integration of proteomic and acetylomic data suggests coordinated changes in protein abundance and lysine acetylation associated with the increased tylosin-equivalent concentration. These results highlight candidate nodes for rational metabolic engineering of S. xinghaiensis.

Streptomyces

Symptoms and treatment response to florensocatib and inhaled tobramycin in bronchiectasis: Post hoc analysis of two randomized trials.

Inhaled antibiotics and DPP-1 inhibitors improve clinical outcomes in bronchiectasis, but whether baseline symptom burden predicts differential treatment responses remains unclear. In this post hoc analysis of two multicenter randomized trials (SAVE-BE, n = 224; TORNASOL, n = 357), we evaluate the association between baseline Quality of Life-Bronchiectasis Respiratory Symptom Scale (QoL-B-RSS) and treatment effects of florensocatib and inhaled tobramycin. In SAVE-BE, florensocatib reduces exacerbation rates versus placebo (relative risk [RR], 0.47; 95% confidence interval [CI], 0.33-0.67; p < 0.0001), with RRs of 0.53 and 0.40 observed in patients with high and low symptom burdens, respectively, but no significant symptomatic improvement. In TORNASOL, tobramycin produces clinically meaningful QoL-B-RSS improvements (exceeding the 8-point cutoff in high-symptom patients) and ameliorates bronchitic symptoms, with greater benefits in those with higher baseline symptom burden. These hypothesis-generating findings suggest that baseline symptom burden may identify differential responses to anti-inflammatory versus anti-infective therapies in bronchiectasis and support its potential as a simple, practical stratification tool to guide personalized treatment.

Humans

Complicated urinary tract infections: evolving definitions, clinical burden, and treatment landscape amid antimicrobial resistance.

INTRODUCTION: Complicated urinary tract infection (cUTI) is a common and heterogeneous infection associated with substantial morbidity, high healthcare utilization, and increasing antimicrobial resistance. Evolving definitions, increasing device use, and changing patient populations have altered its epidemiology and management. Marked variability in diagnostic criteria, clinical trial endpoints within and outside registrational settings, and treatment strategies complicates clinical decision-making and interpretation of therapeutic advances. AREAS COVERED: This review examines contemporary cUTI epidemiology, classification frameworks, and drivers of disease burden. It evaluates resistance trends and their therapeutic implications, alongside stewardship-based management strategies, including empiric antibiotic selection, intravenous-to-oral transition, treatment duration, and source control. Challenges in catheter-associated infection, recurrence, and regulatory endpoint design are discussed, together with the emerging role of novel agents targeting resistant Gram-negative pathogens. EXPERT OPINION: Rising multidrug resistance and limited oral options are reshaping cUTI management, necessitating individualized, stewardship-aligned therapy guided by illness severity and local epidemiology. Current regulatory endpoints inadequately reflect patient-centered outcomes, particularly in the context of asymptomatic bacteriuria. Expanding availability of effective oral agents may enable earlier discharge and outpatient care. Integration of rapid diagnostics and risk stratification will be essential to optimize therapy, limit resistance, and improve outcomes.

Humans

Systematic modular engineering of genome-integrated Escherichia coli MG1655 for high-level 2'-fucosyllactose production.

2'-Fucosyllactose (2'-FL), the most abundant human milk oligosaccharide (HMO), has attracted considerable interest for its prebiotic and immunomodulatory functions, with broad applications in infant nutrition. In this study, we report the development of a high-yield, genome-integrated 2'-FL-producing strain based on Escherichia coli MG1655 through systematic modular optimization. Starting from a single-copy BKHT strain (MGC06), we first optimized the copy number of the &#x3b1;-1,2-fucosyltransferase (&#x3b1;-1,2-FT) gene BKHT. Subsequently, the GDP-L-fucose supply was enhanced through coordinated genomic integration of the gene clusters cpsG-cpsB and gmd-fcl, while the multidrug efflux transporter gene mdfA was integrated to improve product export and strain robustness. BKHT copy number was then re-evaluated in the optimized background, with four copies yielding the highest production. The final engineered strain, harboring all genetic modifications stably integrated into the chromosome, produced 17.18 g/L 2'-FL in shake-flask culture. In fed-batch fermentation using a 5-L bioreactor, this strain achieved a titer of 154.12 g/L after 60&#x202f;h, with a productivity of 2.57 g/L/h. Notably, throughout the entire fermentation process, no antibiotics or inducers were supplemented, underscoring the genetic stability and regulatory compliance of this plasmid-free system. To our knowledge, this represents the highest 2'-FL titer reported to date, positioning our engineered strain as a promising candidate for commercial 2'-FL production.

Escherichia coli