Oral amoxicillin and amoxicillin-clavulanic acid: properties, indications and usage

Integration of paper-based colorimetric microdevice and magnetic nanoparticles affinity for high-throughput capture of antimicrobial resistance-reversing agent from complex natural products

Efficient analysis of active ingredient in complex natural products is crucial for drug discovery, but developing a simple method for this is challenging. The discovery of drugs against bacterial resistance is urgent because drug-resistant bacteria produce β-lactamases, which inactivate antibiotics and increase infection risks, particularly the AmpC β-lactamase. Here, an integrated analytical model based on colorimetric sensing and magnetic nanoparticles (MNPs) affinity chromatography was developed for screening AmpC β-lactamase inhibitors. A paper-based colorimetric microdevice was designed for rapid identification of inhibitors in complex samples. Magnetic nanoparticles affinity was then utilized to capture, isolate and identify the active ingredient by immobilized enzyme technology. This comprehensive analytical model greatly improves the efficiency and accuracy of inhibitor screening compared to other screening methods. Finally, the method was applied to screen AmpC β-lactamase activity inhibitors from five natural medicines. As a result, epicatechin gallate, a potential active component of AmpC β-lactamase, was successfully identified from Rhodiola rosea L. After thorough integration with in vitro antibacterial assays, the activity of the screened compounds was further substantiated. Their binding was further explored by molecular docking and molecular dynamics simulations. Consequently, potential AmpC β-lactamase inhibitors are rapidly and precisely captured from complex natural products by this method, which will offer novel insights into the screening of enzyme inhibitors within natural products.

Chronic amoxicillin shortage led to alternative broad-spectrum antimicrobial use in pediatric clinics

This study aimed to clarify changes in antimicrobial prescribing trends in pediatric clinics before and after the chronic shortage of amoxicillin and amoxicillin-clavulanic acid from 2023 in Japan. Amoxicillin and amoxicillin-clavulanic acid have been in chronic short supply since May 24, 2023 due to increased demand. It is unclear whether this situation has changed the type of oral antimicrobials prescribed by clinics. A retrospective observational study was conducted to analyze antimicrobial prescriptions in pediatric clinics between January and December 2023. The data was collected using information available on a new platform, the Online Monitoring System for Antimicrobial Stewardship at Clinics (OASCIS). The period from March to May was defined as the pre-shortage period, and the period from June to August was defined as the post-shortage period. Antimicrobials were classified using the AWaRe classification proposed by the World Health Organization. The average prescription rate per AWaRe classification in the three months before and after the shortage was compared. A total of 28,888 oral antimicrobial prescriptions were collected. Due to the chronic shortage, the proportion of Access antimicrobials decreased from 53.9 % in the pre-shortage period to 46.8 % in the post-shortage period (p < 0.001). The proportion of Watch antimicrobials increased from 45.9 % to 52.8 % (p < 0.001). Among the Watch antimicrobials, prescriptions for third-generation cephalosporins increased from 18.8 % to 24.7 % (p < 0.001). The chronic shortage of amoxicillin and amoxicillin-clavulanic acid has led to the use of broad-spectrum antimicrobial agents for patients in pediatric clinics.

Oral amoxicillin treatment disrupts the gut microbiome and metabolome without interfering with luminal redox potential in the intestine of Wistar Han rats

Oral antibiotic treatment is well known to be one of the main factors affecting gut microbiota composition by altering bacterial diversity. It decreases the abundance of butyrate-producing bacteria such as Lachnospiraceae and Ruminococcaceae, while increasing abundance of Enterobacteriaceae. The recovery time of commensal bacteria post-antibiotic treatment varies among individuals, and often, complete recovery is not achieved. Recently, gut microbiota disruption has been associated with increased gut oxygen levels and higher redox potential in faecal samples. Given that redox balance is crucial for microbial metabolism and gut health, influencing fermentation processes and maintaining anaerobic conditions, we investigated the impact of oral amoxicillin treatment on the redox potential in the caecum. We used 24 Wistar Han male rats and measured caecal redox potential in situ with a probe, before and after 7 days of amoxicillin treatment, as well as after 7 days of recovery. Additionally, we analysed caecal weight, pH, antioxidant capacity, caecal microbiota, metabolome, and colonic tissue expression of relevant genes involved in the redox potential state. Our findings show that oral amoxicillin treatment significantly reduced archaeal load, and decreased the bacterial alpha diversity and affected bacterial composition of the caecal microbiome. The caecal metabolome was also significantly affected, exemplified by reduced amounts of short chain fatty acids during amoxicillin treatment. While the caecal metabolome fully recovered 7 days post amoxicillin treatment, the microbiome did not fully recover within this time frame. However, amoxicillin did not lead to an increase in luminal redox potential in the cecum during or post amoxicillin treatment. Limited differences were observed for colonic expression of genes involved in intestinal barrier function and generation of reactive oxygen species, except for the catalase gene, which was significantly upregulated post-amoxicillin treatment. Our results suggest that while oral amoxicillin disrupts the gut microbiome and metabolome, it does not directly interfere with gut luminal redox state.

Dose Evaluation and Optimization of Amoxicillin in Children Treated for Lyme Disease

Amoxicillin is commonly used to treat erythema migrans in the first stage of Lyme disease in children, with a recommended dose of 50 mg/kg/day, administered three times a day (q8h). This model-based simulation study aimed to determine whether splitting the same daily dose into two administrations (q12h) would provide comparable drug exposure. A pharmacokinetic model suitable for a pediatric population (age: 1 month to 18 years, weight: 4-80 kg) was selected through a literature review. Simulations were performed with 15,000 virtual patients receiving 16.67 mg/kg/dose q8h, 25 mg/kg/dose q12h, or other q12h dosing variations. The target therapeutic level was defined by the percentage of time that the unbound drug concentration remained above the minimum inhibitory concentration (% fT > MIC) specific to Borrelia burgdorferi, with MICs of 0.06, 0.25, 1, 2, and 4 mg/L, requiring at least 40% and 50% of time for effective treatment. Probability of target attainment (PTA) was considered acceptable if it exceeded 50%, allowing for comparison of dosing schedules. Results indicated that the 50 mg/kg/day divided q12h regimen provided similar drug exposure to the q8h regimen for MICs below 2 mg/L (PTAs >50%). For a MIC of 2 mg/L, PTA was achieved with a higher dose of 30 mg/kg/dose q12h. However, for a MIC of 4 mg/L, the PTA criterion was not met. These findings suggest that a twice-daily dosing of 25 mg/kg/dose provides comparable bactericidal activity to the thrice-daily regimen for MICs between 0.06 and 1 mg/L. This simplified regimen may improve adherence and treatment implementation in children.

BANNMDA: a computational model for predicting potential microbe-drug associations based on bilinear attention networks and nuclear norm minimization

Introduction

Predicting potential associations between microbes and drugs is crucial for advancing pharmaceutical research and development. In this manuscript, we introduced an innovative computational model named BANNMDA by integrating Bilinear Attention Networks(BAN) with the Nuclear Norm Minimization (NNM) to uncover hidden connections between microbes and drugs.

Methods

In BANNMDA, we initially constructed a heterogeneous microbe-drug network by combining multiple drug and microbe similarity metrics with known microbe-drug relationships. Subsequently, we applied both BAN and NNM to compute predicted scores of potential microbe-drug associations. Finally, we implemented 5-fold cross-validation frameworks to evaluate the prediction performance of BANNMDA.

Results and discussion

The experimental results indicated that BANNMDA outperformed state-of-the-art competitive methods. We conducted case studies on well-known drugs such as the Amoxicillin and Ceftazidime, as well as on pathogens such as Bacillus cereus and Influenza A virus, to further evaluate the efficacy of BANNMDA, and experimental outcomes showed that there were 9 out of the top 10 predicted drugs, along with 8 and 9 out of the top 10 predicted microbes having been corroborated by relevant literatures. These findings underscored the capability of BANNMDA to achieve commendable predictive accuracy.

Evaluation of the resistome and gut microbiome composition of hospitalized patients in a health unit of southern Brazil coming from a high animal husbandry production region

Introduction

Antimicrobial resistance (AMR) poses a significant threat to global public health. The One Health approach, which integrates human, animal, and environmental health, highlights the roles of agricultural and hospital settings in the propagation of AMR. This study aimed to analyze the resistome and gut microbiome composition of individuals from a high-intensity animal husbandry area in the western region of Santa Catarina, Southern Brazil, who were subsequently admitted to the University Hospital in the city of Florianopolis, located in the eastern part of the same state.

Methods

Rectal swab samples were collected upon admission and discharge. Metagenomic sequencing and resistome analysis were employed to identify antimicrobial resistance genes (ARGs) and their associated bacterial taxa. Additionally, the impact of the hospital environment on the resistome and microbiome profiles of these patients was assessed.

Results

A total of 247 genetic elements related to AMR were identified, with 66.4% of these elements present in both admission and discharge samples. Aminoglycoside resistance genes were the most prevalent, followed by resistance genes for tetracyclines and lincosamides. Notably, unique resistance genes, including dfrF and mutations in gyrB, were identified at discharge. ARGs were associated with 55 bacterial species, with Lactobacillus fermentum, harboring the ermB gene. (MLSB), detected in both admission and discharge samples. The most prevalent bacterial families included Mycobacteriaceae, Enterobacteriaceae, and Bacteroidaceae. Among these, Mycobacteriaceae was the most abundant, with ARGs primarily associated with mutations in the 16S rRNA gene, RNA polymerase subunits, and gyrases.

Discussion

The study revealed a high prevalence of genes related to aminoglycoside and tetracycline resistance, with a notable increase in certain resistance determinants at discharge, likely influenced by extended antimicrobial use. The presence of mcr genes, associated with colistin resistance, in both admission and discharge samples from a single patient highlights a concerning trend in AMR, particularly in relation to animal husbandry. These findings underscore the substantial impact of antimicrobial use on resistance development and the complex dynamics of the resistome in hospital settings. They also emphasize the influence of local factors, such as intensive animal production, on resistance patterns and advocate for ongoing surveillance and policy development to manage multidrug-resistant bacteria eVectively.

A Pooled Population Pharmacokinetic Study of Oral and Intravenous Administration of Clavulanic Acid in Neonates and Infants: Targeting Effective Beta-Lactamase Inhibition

Data published on the oral clavulanic acid pharmacokinetics in the pediatric population is lacking. This research aimed to describe clavulanic acid disposition following oral and intravenous administration and to provide insights into clavulanic acid exposure based on threshold concentrations for (pre-)term neonates and infants. This pooled population pharmacokinetic study combined four datasets for analysis in NONMEM v7.4.3. Clavulanic acid exposure was simulated using the percentage of time above the threshold concentrations (%fT > CT). Multiple dosage regimens and amoxicillin/clavulanic acid dosage ratios were evaluated. The cohort consisted of 89 (42 oral, 47 intravenous) subjects (403 samples) with a median (range) postnatal age 54.5 days (0-365), gestational age 37.4 weeks (23.0-41.7), and current bodyweight 3.9 kg (0.6-9.0). A one-compartment model with first-order absorption best described clavulanic acid pharmacokinetics with postnatal age as a covariate on the inter-individual variability of clearance. Oral bioavailability was 24.4% in neonates up to 10 days of age. An oral dosing regimen 90 mg/kg/day amoxicillin/clavulanic acid (4:1 ratio) resulted in 40.2% of simulated patients achieving 100% fT > CT,2mg/L. An amoxicillin/clavulanic acid ratio of 4:1 is preferred for neonatal oral regimens due to the higher exposure along the entire %fT > CT range (0-100%) as ratios higher than 4:1 might result in inadequate exposure. Our results highlight substantial exposure differences (%fT > CT) when using threshold concentrations of 1 mg/L vs. 2 mg/L. This first population pharmacokinetic model for clavulanic acid in neonates may serve as a foundational step for future research, once more precise clavulanic acid targets become available.

FDA-approved drugs featuring macrocycles or medium-sized rings

Macrocycles or medium-sized rings offer diverse functionality and stereochemical complexity in a well-organized ring structure, allowing them to fulfill various biochemical functions, resulting in high affinity and selectivity for protein targets, while preserving sufficient bioavailability to reach intracellular compartments. These features have made macrocycles attractive candidates in organic synthesis and drug discovery. Since the 20th century, more than three-score macrocyclic drugs, including radiopharmaceuticals, have been approved by the US Food and Drug Administration (FDA) for treating bacterial and viral infections, cancer, obesity, immunosuppression, inflammatory, and neurological disorders, managing cardiovascular diseases, diabetes, and more. This review presents 17 FDA-approved macrocyclic drugs during the past 5 years, highlighting their importance and critical role in modern therapeutics, and the innovative synthetic approaches for the construction of these macrocycles.

Development of a β-lactamase-based aggregation-induced emission lateral flow strip for the detection of clavulanic acid in Milk

Lack of biorecognition elements significantly hinders the development of rapid detection methods for clavulanic acid (CA). To address this, we expressed Class A β-lactamases PC1 in vitro and demonstrated its high affinity for CA. Then we investigated the recognition mechanisms of PC1 for CA and identified key contact amino acids: Ser70, Lys73, Ser130, Glu166, and Lys234. Furthermore, PC1 was utilized as a novel biorecognition element to establish a "pseudo-immuno" lateral flow strip (LFS) for CA detection. Aggregation-induced emission fluorescence microspheres (AIE@FM) and biotin-streptavidin (Bio-SA) were integrated to improve the detection performance of PC1-based LFS. Results showed that the sensitivity (cut-off value) of PC1-based AIE(Bio-SA)-LFS was enhanced 2-fold and 4-fold compared to basic AIE@FM-LFS and traditional Au-based LFS, respectively. Eventually, the proposed PC1-based AIE(Bio-SA)-LFS was successfully verified in milk samples with a cut-off value of 20 ng mL-1. This study provides a powerful tool for on-site CA monitoring for the first time.

Phytochemical Analysis and Antimicrobial Activity of Terminalia bellirica (Gaertn.) Roxb. and Terminalia chebula Retz. Fruit Extracts Against Gastrointestinal Pathogens: Enhancing Antibiotic Efficacy

Terminalia bellirica (Gaertn) Roxb. and Terminalia chebula Retz. are significant botanicals in ancient Ayurvedic medicine. They are renowned for their therapeutic properties, notably in addressing gastrointestinal (GI) diseases. These plants have undergone thorough examination related to their antibacterial, anti-inflammatory, and antioxidant properties, which make them highly efficient natural treatments for controlling gastrointestinal infections. The current research demonstrated the antibacterial efficacy of fruit extracts of Terminalia bellirica and Terminalia chebula against Bacillus cereus, Shigella sonnei, Shigella flexneri, and Salmonella typhimurium. We performed disc diffusion and liquid microdilution experiments to evaluate the antibacterial efficacy. All extracts of Terminalia bellirica and Terminalia chebula showed good antibacterial effects against B. cereus and S. flexneri. The minimum inhibitory concentration (MIC) values ranged from 94 µg/mL to 556 µg/mL. The methanolic extracts from both plants also showed noteworthy antibacterial activity against S. sonnei and S. typhimurium, with MIC values of 755 µg/mL for both. Fractional inhibitory concentration studies revealed additive interactions between some conventional antibiotics and the plant extracts when used concurrently. Liquid chromatography-mass spectrometry (LC-MS) analyses revealed that the T. bellirica and T. chebula extracts contained various tannins including methyl gallate, propyl gallate, gallic acid, and ellagic acid. Lethality assays conducted using Artemia franciscana Kellogg nauplii indicated that all the plant extracts are non-toxic. The antibacterial properties and absence of toxicity in T. bellirica and T. chebula fruit extracts indicate their potential for antibiotic development, warranting additional mechanistic and phytochemical studies.

Cytotoxicity and Antimicrobial Efficacy of Fe-, Co-, and Mn-Doped ZnO Nanoparticles

Zinc oxide nanoparticles (ZnO NPs) are one of the most widely used nanoparticulate materials due to their antimicrobial properties. However, the current use of ZnO NPs is hindered by their potential cytotoxicity concerns, which are likely attributed to the generation of reactive oxygen species (ROS) and the dissolution of particles to ionic zinc. To reduce the cytotoxicity of ZnO NPs, transitional metals are introduced into ZnO lattices to modulate the ROS production and NP dissolution. However, the influence of the doping element, doping concentration, and particle size on the cytotoxicity and antimicrobial properties remains unexplored. This study presents a comprehensive investigation of a library of doped ZnO NPs to elucidate the relationship between their physicochemical properties, antimicrobial activity against Escherichia coli (E. coli), and cytotoxicity to mammalian cells. The library comprises 30 variants, incorporating three different dopant metals-iron, manganese, and cobalt-at concentrations of 0.25%, 1%, and 2%, and calcined at three temperatures (350 °C, 500 °C, and 600 °C), resulting in varied particle sizes. These ZnO NPs were prepared by low temperature co-precipitation followed by high-temperature calcination. Our results reveal that the choice of dopant elements significantly influences both antimicrobial efficacy and cytotoxicity, while dopant concentration and particle size have comparatively minor effects. High-throughput UV-visible spectroscopic analysis identified Mn- and Co-doped ZnO NPs as highly effective against E. coli under standard conditions. Compared with undoped ZnO particles, Mn- and Co-doping significantly increased the oxidative stress, and the Zn ion release from NPs was increased by Mn doping and reduced by Fe doping. The combined effects of these factors increased the cytotoxicity of Mn-doped ZnO particles. As a result, Co-doped ZnO particles, especially those with 2 wt.% doping, exhibited the most favourable balance between enhanced antibacterial activity and minimized cytotoxicity, making them promising candidates for antimicrobial applications.

The role of older antibiotics in the treatment of skin and soft tissue infections: current perspectives

PURPOSE OF REVIEW

The aim is to discuss the evidence and recent literature on the role of older antibiotics in the treatment of skin and soft tissue infections (SSTIs).

RECENT FINDINGS

The choice of therapy for SSTIs is complicated in view of the rising antimicrobial resistance (AMR) and the availability of new antibiotics. SSTIs are predominantly caused by Staphylococcus aureus and beta-hemolytic streptococci, but other organisms can be involved in patients with comorbidities or post trauma. Treatment options are dictated by the accessibility and cost of newer antibiotics in resource-constrained settings. 'Old antibiotics' including β-lactams, doxycycline, trimethoprim-sulfamethoxazole (TMP/SMX), clindamycin, azithromycin, and ciprofloxacin remain good choices in treating SSTIs. They offer affordable options for outpatient settings. Only few randomized trials have addressed the role of the old agents in SSTIs treatment. Studies suggest that these agents remain effective for empirical and targeted therapy based on the epidemiological context. Ongoing surveillance and clinical trials are needed to assess the role of these agents and to integrate them into modern SSTIs management, supporting sustainable treatment models in both high-income and low-income settings.

SUMMARY

Older antibiotics can be effectively used in treating SSTIs, provided their use is guided by current epidemiological data or culture and susceptibility results.

Comparing Prescribing Behaviors and Clinician Experiences Between Multiplex PCR/Pooled Antibiotic Susceptibility Testing and Standard Urine Culture in Complicated UTI Cases

Background/Objectives: We aimed to compare the prescribing behavior and clinical experience of urology providers when using the combined multiplex polymerase chain reaction (M-PCR)/Pooled Antibiotic Susceptibility Testing (P-AST) diagnostic test versus the standard urine culture (SUC) in the same set of patients previously reported to have improved clinical outcomes with M-PCR/P-AST. Methods: We conducted a multi-centered, prospective, observational study (clinical trial registration: NCT05091931) with Western Institutional Review Board (IRB) approval (20214705). Adult subjects were split between the M-PCR/P-AST (n = 250) and SUC arms (n = 135). Treatment details were determined by clinician and subject surveys. Differences in prescribed antibiotics were compared using the Chi-square or Fisher's exact test. Results: There was no significant difference in the overall use of "access" antibiotics (p = 1.0) or first-line drugs (p = 0.4483) between M-PCR/P-AST and SUC. Nitrofurantoin (p = 0.0172) and metronidazole (p = 0.0309) were more frequently used with M-PCR/P-AST, while amoxicillin/clavulanate (p = 0.0008), cefuroxime (p = 0.0378), and ertapenem (p = 0.0378) were more frequently used with SUC. Conclusions: The use of M-PCR/P-AST to guide complicated UTI management was not associated with the increased use of non-first-line antibiotics, such as carbapenems, compared to SUC. Combined with the prior reported evidence of improved patient outcomes in this same set of patients, this test should be considered for utilization when managing complicated UTI cases.

Antibiotic Dispensing Practices Among Community Retail Pharmacies and Registered Drugstores: Results from a Simulated Client Study in Lilongwe, Malawi

Introduction

Antimicrobial resistance (AMR) is largely driven by the inappropriate use of antibiotics. This has been attributed to the non-prescription sale of antibiotics in retail drug outlets. Despite the rising number of retail drug outlets in Malawi, the practice of drug dispensing in private pharmacies has not been evaluated. This study therefore assessed the prevalence of non-prescription sales of antibiotics in retail drug outlets in Lilongwe, Malawi.

Methods

A community-based simulated client cross-sectional study was conducted in Lilongwe, Malawi from December 2023 to February 2024 using mystery shopping. Data were analyzed using IBM SPSS software version 29 using both descriptive and Analytical statistics. We computed simple proportions and conducted a hypotheses test using Chi-Square to test for Significance.

Results

Antibiotic dispensing practices were surveyed in 51 retail drug outlets comprising 36 retail pharmacies and 15 drugstores. 35.3% (n=18) of the drug outlets had drug dispensing done by pharmacists, 13.7% (n=7) by pharmacy technicians, 21.5% (n=11) by pharmacy assistants and 25.5% (n=15) by drug dispensers who had no pharmacy-related training. The rate of non-prescription sales of antibiotics ranged between 53% for acute diarrhoea and 92% for upper respiratory tract infections. Amoxicillin was the most dispensed antibiotic across all case scenarios. Over 50% of dispensed antibiotics were done upon recommendation of the drug dispensers in the absence of a doctor's prescription. Furthermore, for all the dispensed antibiotics across all case scenarios, no advice was given for finishing a full course of the antibiotics.

Conclusion

This study found high rates of over-the-counter dispensing of antibiotics, which call for urgent and comprehensive regulatory measures to control antibiotic consumption in an urban part of Malawi that risks increased AMR. These could range from enacting stringent antibiotic dispensing policies to deploying digital systems to monitor prescription practices and community education on rational antibiotic use.

Rapid Dynamic Surface-Enhanced Raman Spectroscopy Detection of Amoxicillin-Mediated Morphological Changes in a Pathogen for Diagnosis of Clinical Urine Samples

The swift and stable detection of pathogens in urine samples holds significant implications for the immediate clinical diagnosis and treatment of urinary tract infections (UTIs). In this study, we propose a detection strategy utilizing a hybrid substrate composed of graphene oxide (GO) and silver nanoparticles (Ag NPs) for the detection of pathogens subjected to amoxicillin-mediated (amo-mediated) treatment. This strategy employs dynamic surface-enhanced Raman spectroscopy (D-SERS) for stable and rapid detection, capturing signal variations induced by amo-mediated changes in pathogen morphology. During the 5 min D-SERS detection time window, stable SERS signals were detected for three types of pathogens and four types of pathogens were successfully distinguished using principal component analysis (PCA). In comparison to conventional nanosubstrates, the GO/Ag NP hybrid substrate exhibits outstanding stability and enhancement effects. This approach enables the dual detection of the pathogen cell structure and metabolites, facilitating specific identification of pathogens in the urinary tract, with a detection limit for Escherichia coli reaching 1 × 104 colony-forming units (CFU)/mL, meeting the clinical microbiology laboratory diagnostic standards for UTIs (105 CFU/mL). Testing of 188 clinically collected urine samples using this strategy yielded a sensitivity (SENS) of 86.4% and a specificity (SPC) of 89.7%. This introduces a novel method for diagnosing UTIs, offering broad applications in the field of clinical pathogen detection.

Comparative Pharmacokinetics and Egg Residues of Amoxicillin, Single and in Combination with Bromhexine, in Laying Hens

The need for antibiotics in commercial laying hens is increasing owing to intensive farming systems. Amoxicillin trihydrate (AMX), an aminopenicillin β-lactam antibiotic, exerts broad bactericidal activity. However, its short half-life necessitates frequent administration to ensure efficacy, thus limiting its use. Herein, we investigated the effect of concurrent administration of bromhexine hydrochloride (BRM), a mucolytic agent, on AMX pharmacokinetics, performing a comparative pharmacokinetic analysis of AMX administration alone and in combination with BRM. AMX (50 mg/kg) was administered by oral gavage once daily for three days alone or in combination with 10 mg/kg BRM. Plasma and egg samples were collected to evaluate pharmacokinetic profiles and egg residues. The area under the curve and maximum plasma concentration values were significantly higher in the AMX + BRM group than the AMX only group. However, there were no significant differences in AMX half-life in the elimination phase (T1/2), elimination rate constant (kel), or apparent clearance (CL/F) values. In the egg residue study, the withdrawal period for AMX was 5 days in both groups, with no significant difference when using the maximum residue limit (MRL) of 10 μg/kg. The concentration of BRM in the eggs remained at 100 μg/kg up to the fourth day following drug administration. Conclusion: These results confirmed that BRM co-administration increased systemic exposure to AMX, with a negligible residual impact of amoxicillin in eggs.

Antibiotics Knowledge and Prescription Patterns Among Dental Practitioners in Croatia, Bosnia and Herzegovina, and Serbia: A Comparative E-Survey with a Focus on Medically Healthy and Compromised Patients

BACKGROUND

The non-specific prescription of antibiotics, especially in dentistry, contributes to the global problem of antimicrobial resistance and highlights the need for education on the proper use and serious consequences of overprescribing these drugs. The main objective of this study is to assess and evaluate antibiotic knowledge and prescribing patterns in dental practice in Croatia, Bosnia and Herzegovina, and Serbia, focusing on understanding the rationale for prescribing, adherence to evidence-based guidelines, and dentists' awareness of antibiotic resistance.

METHODS

A total of 795 dentists participated in this electronic cross-sectional survey (Croatia N = 336, Bosnia and Herzegovina N = 176, and Serbia N = 283). The study utilized a self-structured questionnaire to collect data on various aspects of antibiotic use, including knowledge, prescribing practices, awareness of guidelines, and demographic and professional information about dentists. Data analysis included the Mann-Whitney test, the Kruskal-Wallis test with post hoc analysis, and chi-square tests, with statistical significance set at p < 0.05.

RESULTS

The overall score for the participants' knowledge of antibiotics was 6.40 ± 1.40 out of a maximum of eight points, which indicates a generally good level of knowledge among dentists. Factors such as gender, specialty, and practice location significantly influenced the level of knowledge (p < 0.05). However, actual prescribing practice was a cause for concern. Only 66.1% of Croatian dentists felt they had received adequate training during their studies, and even fewer in Serbia (48.4%) and Bosnia (46.6%). It is noteworthy that 9.7% of dentists in Bosnia and Herzegovina prescribe antibiotics at the request of patients, while 22.3% of Croatian and 25.4% of Serbian dentists do so. Many dentists prescribe no or only one antibiotic per week. In addition, 50.9% of Croatian dentists reported adverse effects related to the use of antibiotics, while only 31.3% of Bosnian and 33.6% of Serbian dentists reported similar experiences.

CONCLUSIONS

While the study results indicate that dentists in the region generally possess good knowledge of antibiotic use, there are significant discrepancies between this knowledge and actual prescribing practices. This highlights the need for enhanced educational programs and awareness initiatives focused on proper antibiotic guidelines to improve prescribing behaviors.

Mucoadhesive in situ nasal gel of amoxicillin trihydrate for improved local delivery: Ex vivo mucosal permeation and retention studies

Orally administered amoxicillin is recommended as the first-line treatment of acute bacterial rhinosinusitis (ABR) and given in a high-dose regimen. However, the risk of various systemic adverse reactions and low oral bioavailability are unbearable, increasing the threat of antibiotic resistance. Therefore, nasal delivery of amoxicillin can be a potential approach for effectively treating ABR locally, as well as overcoming those drawbacks. In a way to guarantee the effectiveness for local therapy in nasal cavity, the permeation and retention properties are of significant importance considerations. Accordingly, the present work aimed to investigate the characteristics with respect to the nasal applicability of the in situ gelling amoxicillin trihydrate (AMT) and further evaluate its permeability and retention properties through human nasal mucosa. The lyophilized formulations were characterized utilizing the Differential Scanning Calorimetry (DSC) and X-ray Powder Diffraction (XRPD), and also evaluated for its polarity, reconstitution time, droplet size distribution, mucoadhesive properties, and ex vivo permeability and retention studies. The results confirmed that the in situ gelling AMT formulations possess adequate mucoadhesive behavior, especially the formulation containing 0.3 % of gellan gum. Substantially, the in situ gelling AMT formulations were able to retain the drug on the surface of nasal mucosa instead of permeating across the membrane; thus, suitable for treating nasal infections locally. Altogether, the in situ gelling systems demonstrates promising abilities as a delivery platform to enhance local application of AMT within the nasal cavity.

Adsorption of amoxicillin by chitosan and alginate biopolymers composite beads

Due to its widespread use and incomplete breakdown in the human body, amoxicillin has been detected in receiving water bodies. This raises significant concerns, like the promotion of antibiotic resistance, toxicity towards aquatic life, disruption of the natural balance of microbial communities within these water bodies, and the struggle of effectively removal by the traditional wastewater treatment plants. Consequently, exploring new processes to complement the existing methods is crucial. Adsorption, a promising highly efficient, selective, and versatile technique, can effectively remove contaminants, making it useful in various industries such as water treatment, pharmaceuticals, and environmental remediation. Several adsorbents are documented in the literature for drug adsorption; however, their fabrication often involves more complex steps and substances compared to chitosan and alginate, which are natural polymers that are biocompatible, non-toxic, and biodegradable. Their tunable properties and ease of modification enhance their efficacy in environmental remediation. Therefore, the novelty of this article is to understand the interaction of amoxicillin with chitosan and alginate adsorbents easily synthetized using the dripping technique. This approach allows us to explore basic principles that can be applied to more complex systems in future studies. The optimal pH for both beads was found to be 4, with adsorption capacities of 74.2 ± 0.3 mg g-1 for alginate and 80.4 ± 0.2 mg g-1 for chitosan, using 1 g of adsorbent. Kinetics studies indicated that external diffusion governs adsorption for alginate, while internal diffusion governs adsorption for chitosan. This approach underscores the potential of chitosan and alginate beads as effective adsorbents for mitigating antibiotic contamination in water systems, offering a sustainable complement to traditional treatment methods.

SIL-IS LC-ESI-MS/MS method for simultaneous quick detection of amoxicillin and clavulanic acid in human plasma: Development, validation and its application to a pharmacokinetics study

A liquid chromatography electrospray ionization tandem mass spectrometry method with amoxicillin-d4 as the stable isotope-labeled internal standard for simultaneous quick detection of amoxicillin and clavulanic acid in human plasma was developed and validated. Chromatographic separations were performed on a Hedera ODS-2 column (2.1 × 150 mm, 5 μm). The mobile phases for gradient elution were aqueous solution containing 0.2% acetic acid (AA) (mobile phase A) together with organic phase solution (acetonitrile and methanol mixed solution, mobile phase B). Mass spectrometry was performed using negative electrospray ionization in multiple reaction monitoring mode. The target fragment ion pairs of amoxicillin, clavulanic acid and amoxicillin-d4 were m/z 364.1 → 223.1, 198.1 → 135.9 and 368.1 → 227.1, respectively. The linear ranges of this method were 40-5,000 ng/ml for amoxicillin and 30-2,500 ng/ml for clavulanic acid, with coefficient of determination > 0.9900. This method validation included selectivity, standard curve, lower limit of quantitation, accuracy, precision, recovery, matrix effect (hemolytic matrix and hyperlipidemic matrix), carryover, stability, dilution reliability and incurred sample reanalysis study. A successful application of this method was realized in a pharmacokinetic study after administration of amoxicillin-clavulanic acid potassium granules.

Combinations of Terminalia bellirica (Gaertn.) Roxb. and Terminalia chebula Retz. Extracts with Selected Antibiotics Against Antibiotic-Resistant Bacteria: Bioactivity and Phytochemistry

Antimicrobial resistance (AMR) has arisen due to antibiotic overuse and misuse. Antibiotic resistance renders standard treatments less effective, making it difficult to control some infections, thereby increasing morbidity and mortality. Medicinal plants are attracting increased interest as antibiotics lose efficacy. This study evaluates the antibacterial activity of solvent extracts prepared using Terminalia bellirica and Terminalia chebula fruit against six bacterial pathogens using disc diffusion and broth microdilution assays. The aqueous and methanol extracts of T. bellirica and T. chebula showed substantial zones of inhibition (ZOIs) against Staphylococcus aureus and methicillin-resistant S. aureus (MRSA). The activity against those bacteria was strong, with minimum inhibitory concentrations (MIC) ranging from 94 µg/mL to 392 µg/mL. Additionally, the T. bellirica methanolic extract showed noteworthy antibacterial activity against Escherichia coli and an extended spectrum β-lactamase (ESBL) E. coli strain (MIC values of 755 µg/mL for both). The aqueous T. bellirica and T. chebula extracts also inhibited Klebsiella pneumoniae growth (MIC values of 784 µg/mL and 556 µg/mL, respectively). The corresponding methanolic extracts also inhibited ESBL K. pneumoniae growth (MIC values of 755 µg/mL and 1509 µg/mL, respectively). Eighteen additive interactions were observed when extracts were combined with reference antibiotics. Strong antagonism occurred when any of the extracts were mixed with polymyxin B. Liquid chromatography-mass spectroscopy (LC-MS) analysis of the extracts revealed several interesting flavonoids and tannins, including 6-galloylglucose, 1,2,6-trigalloyl-β-D-glucopyranose, 6-O-[(2E)-3-phenyl-2-propenoyl]-1-O-(3,4,5-trihydroxybenzoyl)-β-D-glucopyranose, propyl gallate, methyl gallate, sanguiin H4, hamamelitannin, pyrogallol, gallic acid, ellagic acid, chebulic acid, and chebuloside II. All extracts were nontoxic in brine shrimp assays. This lack of toxicity, combined with their antibacterial activities, suggests that these plant species may be promising sources of antibacterial compound(s) that warrant further study.

Genomic Diversity of Streptomyces clavuligerus: Implications for Clavulanic Acid Biosynthesis and Industrial Hyperproduction

Streptomyces clavuligerus is a species used worldwide to industrially produce clavulanic acid (CA), a molecule that enhances antibiotic effectiveness against β-lactamase-producing bacterial strains. Despite its low inherent CA production, hyper-producing strains have been developed. However, genomic analyses specific to S. clavuligerus and CA biosynthesis are limited. Genomic variations that may influence CA yield were explored using S. clavuligerus strain genomes from diverse sources. Despite the slight differences obtained by similarity index calculation, pan-genome estimation revealed that only half of the genes identified were present in all strains. As expected, core genes were associated with primary metabolism, while the remaining genes were linked to secondary metabolism. Differences at the sequence level were more likely to be found in regions close to the tips of the linear chromosome. Wild-type strains preserved larger chromosomal and plasmid regions compared to industrial and/or hyper-producing strains; such a grouping pattern was also found through refined phylogenetic analyses. These results provide essential insights for the development of hyper-producing S. clavuligerus strains, attending to the critical demand for this antibiotic enhancer and contributing to future strategies for CA production optimization.

Antioxidant and Pro-Oxidant Properties of Selected Clinically Applied Antibiotics: Therapeutic Insights

BACKGROUND

The balance between antioxidants and pro-oxidants plays a significant role in the context of oxidative stress, influenced by both physiological and non-physiological factors.

OBJECTIVES

In this study, 18 prescribed antibiotics (including doxycycline hydrochloride, tigecycline, rifampicin, tebipenem, cefuroxime, cefixime, potassium clavulanate, colistin, ampicillin, amoxicillin, amikacin, nalidixic acid, azithromycin, pipemidic acid trihydrate, pivmecillinam, aztreonam, fosfomycin sodium, and ciprofloxacin) were subjected to simultaneous determination of antioxidant and pro-oxidant potential to assess if pro-oxidant activity is a dominant co-mechanism of antibacterial activity or if any antibiotic exhibits a balanced effect.

METHODS

This study presents a recently developed approach for the simultaneous assessment of antioxidant and pro-oxidant potential on a single microplate in situ, applied to prescribed antibiotics.

RESULTS

Ten antibiotics from eighteen showed lower antioxidant or pro-oxidant potential, while five exhibited only mild potential with DPPH50 values over 0.5 mM. The pro-oxidant antioxidant balance index (PABI) was also calculated to determine whether antioxidant or pro-oxidant activity was dominant for each antibiotic. Surprisingly, three antibiotics-doxycycline hydrochloride, tigecycline, and rifampicin-showed significant measures of both antioxidant and pro-oxidant activities. Especially notable was tebipenem, a broad-spectrum, orally administered carbapenem, showed a positive PABI index ratio, indicating a dominant antioxidant over pro-oxidant effect.

CONCLUSIONS

These findings could be significant for both therapy, where the antibacterial effect is enhanced by radical scavenging activity, and biotechnology, where substantial pro-oxidant activity might limit microbial viability in cultures and consequently affect yield.

Appropriateness of antibiotic prescribing in paediatrics: retrospective controlled study assessing a multifaceted intervention in Northern Italy in a 7-year period

BACKGROUND

Academic detailing, audit and feedback, and peer comparison have been advocated as effective ways to promote appropriateness of prescribing and antimicrobial stewardship (AMS). This study explored the effectiveness of a multifaceted intervention aimed at supporting the appropriateness of antibiotic prescribing in paediatrics.

METHODS

Over the course of 7 years, all 89 paediatricians of the Local Health Authority (LHA) of Reggio Emilia (530 000 residents) were provided with scientific literature focused on antimicrobial resistance and the appropriateness of use of specific antibiotics, together with local data on antimicrobial resistance and prescribing reports comparing each paediatrician with colleagues in the same district and with local averages. Prescribing rates of specific target antibiotics/classes of antibiotics were evaluated by comparing Reggio-Emilia with the other seven LHAs of the Emilia-Romagna Region (control area), adjusting for prescriptions during a 2-year baseline period.

RESULTS

A significant increase in the rate of amoxicillin prescriptions (91 more per 1000 children/year) was observed in the intervention area compared with the control area along with a significant reduction in the rate of amoxicillin+clavulanate prescriptions (70 fewer per 1000 children/year) and a significant increase in the ratio of their prescription rates. No differences were observed in cephalosporin and macrolide prescription rates and overall antibiotic prescriptions.

CONCLUSIONS

Improvements in prescribing appropriateness were observed. This study confirms the importance of an audit and feedback approach through small group meetings supported by scientific literature, local resistance data and prescribing reports. Such approach should always be considered as part of multifaceted interventions to promote AMS.

Antibiotic Prescribing Habits in Endodontics among Dentists in the Federation of Bosnia and Herzegovina-A Questionnaire-Based Study

BACKGROUNDS

Antibiotics are used in endodontic treatment to control acute odontogenic infection and for prophylactic purposes. This study aimed to investigate the knowledge of dentists from the Federation of Bosnia and Herzegovina about the choice and the routes of antibiotic administration in endodontics.

METHODS

This cross-sectional study involved dentists in Federation of Bosnia and Herzegovina health institutions. The Dental Chamber sent a twelve-question survey to members' email addresses. They were asked about the type, dosage, indications, and side effects of antibiotics used in endodontics. The obtained data were screened and analyzed.

RESULTS

A total of 180 questionnaires were filled out. The most commonly prescribed antibiotic was amoxicillin with clavulanic acid. Pulp necrosis with symptomatic apical periodontitis, swelling, and moderately severe symptoms were the main indications for the therapeutic use of antibiotics. Amoxicillin, administered orally at 2 g 1 h before endodontic surgery for patients with bacterial endocarditis, was mostly indicated for the prophylactic use of antibiotics.

CONCLUSIONS

Based on the results of this study, we can conclude that dentists from the Federation of Bosnia and Herzegovina have limited knowledge regarding antibiotic use in endodontics. Educational activities and campaigns are necessary to raise awareness about antibiotics in dental medicine in the Federation of Bosnia and Herzegovina.

Antibiotic-induced severe cutaneous adverse reactions: a single-center retrospective study over ten years

Objective

Severe cutaneous adverse reactions (SCARs) are rare but life-threatening, with antibiotics being the main cause. This retrospective study from a single center was designed to analyze the culprit drugs, clinical features and treatment outcomes of antibiotic-induced SCARs.

Methods

We analyzed cases of antibiotic-induced SCARs in a tertiary hospital in China between January 2013 and January 2024, including Steven-Johnson syndrome (SJS) or Stevens-Johnson syndrome-toxic epidermal necrolysis (SJS-TEN) overlap, toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS) and acute generalized exanthematous pustulosis (AGEP). Descriptive analysis of the demographic characteristics, clinical manifestations, treatment and prognosis were carried out.

Results

Among 354 cases of SCARs, 63 validated antibiotic-related cases were included. Cephalosporins (31.7%), penicillins (25.4%), and quinolones (19.0%) were the most common triggers for SCARs. Overall, liver (50.8%), lungs (31.7%), and kidneys (23.8%) were the most frequently affected organ in SCARs cases. Eight patients (28.6%) in the SJS/SJS-TEN overlap group and 8 patients (80.0%) in the TEN group received combination therapy of corticosteroids and IVIG. Patients with SCARs caused by penicillins or cephalosporins could receive alternative treatments such as lincomamides, quinolones, and tetracyclines. The mortality rate in the TEN group was the highest at 20.0%, followed by the SJS/SJS-TEN overlap group (7.1%), and no deaths were observed in the DRESS and AGEP groups.

Conclusion

The identification of the culprit antibiotics and the application of alternative antibiotic therapies are crucial for the management of antibiotic-induced SCARs. If complicated underlying conditions and complications like advanced age, cancer and pneumonia coexist with SCARs, patients might be more at risk for mortality.

Phyllanthus niruri Linn.: Antibacterial Activity, Phytochemistry, and Enhanced Antibiotic Combinatorial Strategies

Antimicrobial resistance (AMR) is a global public health threat caused by the misuse and overuse of antibiotics. It leads to infections becoming difficult to treat, causing serious illness, disability, and death. Current antibiotic development is slow, with only 25% of current antibiotics exhibiting novel mechanisms against critical pathogens. Traditional medicinal plants' secondary metabolites offer potential for developing novel antibacterial compounds. These compounds, often with strong antimicrobial activity, can be used to develop safe and effective antibacterial chemotherapies. This study investigated the antibacterial activity of Phyllanthus niruri Linn. extracts against a panel of bacterial pathogens using disc diffusion and microdilution assays and quantified by calculation of minimum inhibition concentration (MIC). Additionally, the effects of combinations of the extracts and selected conventional antibiotics were examined by sum of fractional inhibition concentration (ƩFIC) calculation and isobologram analysis. Liquid chromatography-mass spectrometry (LC-MS) phytochemistry analysis was used to identify noteworthy compounds in the active extracts and the Artemia nauplii bioassay was used to evaluate toxicity. The aqueous and methanolic extracts exhibited notable antibacterial activity in the broth microdilution assay against Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) (MIC = 669 µg/mL and 738 µg/mL, respectively). The methanolic extract also showed noteworthy antibacterial action in the broth assay against Klebsiella pneumoniae (MIC = 738 µg/mL). The aqueous extract had noteworthy growth inhibitory activity against Bacillus cereus (MIC = 669 µg/mL), whilst the methanolic extract demonstrated good antibacterial activity against that bacterium (MIC = 184 µg/mL). The aqueous and methanol extracts showed minimal antibacterial action against Shigella flexneri and Shigella sonnei. The extracts were subjected to LC-MS analysis, which revealed several interesting phytochemicals, including a variety of flavonoids and tannins. The antibacterial activity and lack of toxicity of the P. niruri extracts indicates that they may be worthwhile targets for antibiotic development and further mechanistic and phytochemistry studies are required.

Antibiotic prescribing patterns among dentists in Italy and Albania: A comparative questionnaire analysis

Objective

To investigate the therapeutic and prophylactic use of antibiotics in dentistry in two countries.

Methods

This study used questionnaires to examine the prescribing habits of dentists in Italy (9th country in Europe for systemic antibiotic administration) and Albania an Extra European Union Country. A total of 1300 questionnaires were sent to Italian and Albanian dentists.

Results

In total, 180 Italian and 180 Albanian dentists completed the questionnaire. Penicillin use was higher in Italy (96.6 %) than Albania (82.8 %). Only 26.1 % of Italian dentists and 32 % of Albanian dentists followed the national guidelines for antibiotic administration.

Conclusions

Dentists tend to overprescribe antibiotics for treating existing conditions or as prophylaxis. They also highlighted a lack of adherence to established guidelines for antibiotic use. In addition, factors such as age, nationality, and sex appeared to influence the choice of antibiotics.

Clinical significance

Recently, the growth of antibiotic-resistant bacteria has become a global concern. The authors of this article highlight how dentists often prescribe antibiotics without a real need. Limiting the use of antibiotics in this category may help mitigate antibiotic resistance.

Salmonella spp. in Domestic Ruminants, Evaluation of Antimicrobial Resistance Based on the One Health Approach-A Systematic Review and Meta-Analysis

Salmonella spp. pose a global threat as a leading cause of foodborne illnesses, particularly prevalent in the European Union (EU), where it remains the second cause of foodborne outbreaks. The emergence of antimicrobial resistance (AMR) in Salmonella spp. has become a critical concern, complicating treatment strategies and escalating the risk of severe infections. The study focuses on large and small ruminants, identifying a prevalence of Salmonella spp. in slaughterhouses and revealing varied AMR rates across antimicrobial families throughout a meta-analysis. Also, comparison with AMR in human medicine was carried out by a systematic review. The results of the present meta-analysis displayed a prevalence of Salmonella spp. in large and small ruminants at slaughterhouses of 8.01% (8.31%, cattle; 7.04%, goats; 6.12%, sheep). According to the AMR of Salmonella spp., 20, 14, and 13 out of 62 antimicrobials studied were classified as low (<5%), high (>5% but <10%), and very high (>10%), respectively. Salmonella spp. did not display AMR against aztreonam, mezlocillin, ertapenem, meropenem, cefoxitin, ceftazidime, levofloxacin, tilmicosin, linezolid, fosfomycin, furazolidone, quinupristin, trimethoprim and spectinomycin. In contrast, a prevalence of 100% of AMR has been described against ofloxacin, lincomycin, and cloxacillin. In the context of the main antibiotics used in the treatment of human salmonellosis, azithromycin was shown to have the highest resistance among Salmonella spp. isolates from humans. Regarding cephalosporins, which are also used for the treatment of salmonellosis in humans, the prevalence of Salmonella spp. resistance to this class of antibiotics was similar in both human and animal samples. Concerning quinolones, despite a heightened resistance profile in Salmonella spp. isolates from ruminant samples, there appears to be no discernible compromise to the efficacy of salmonellosis treatment in humans since lower prevalences of AMR in Salmonella spp. isolated from human specimens were observed. Although the resistance of Salmonella spp. indicates some degree of concern, most antibiotics are not used in veterinary medicine. Thus, the contribution of cattle, sheep and goats to the rise of antibiotic resistance of Salmonella spp. and its potential impact on public health appears to be relatively insignificant, due to their low prevalence in carcasses and organs. Nevertheless, the observed low prevalence of Salmonella spp. in ruminants at slaughterhouse and the correspondingly low AMR rates of Salmonella spp. to key antibiotics employed in human medicine do not indicate that ruminant livestock poses a substantial public health risk concerning the transmission of AMR. Thus, the results observed in both the meta-analysis and systematic review suggests that AMR is not solely attributed to veterinary antibiotic use but is also influenced by factors such as animal health management (i.e., biosecurity measures, prophylactic schemes) and human medicine.

Removal of organic contamination from wastewater using granular activated carbon modified-Polyethylene glycol: Characterization, kinetics and isotherm study

To effectively remove Diazinon (DZ), Amoxicillin (AMX), and Crystal Violet (CV) from aquatic environments, a novel granular activated carbon (GAC) modified with Polyethylene glycol 600 (PEG) was created and manufactured. The chemical properties were investigated using a variety of characteristic analyses, including FT-IR, XRD, FESEM, and N2 adsorption/desorption. The effectiveness of GAC-PEG's adsorption for the removal of DZ, AMX, and CV was assessed under a variety of conditions, including a pH of 4-9 for the solution, 0.003-0.05 g doses of adsorbent, 50-400 ppm starting concentration, and a reaction time of 5-25 min. For DZ, AMX, and CV adsorption, the maximum adsorption capacity (Qmax) was 1163.933, 1163.100, and 1150.300 mg g-1, respectively. The Langmuir isotherm described all of the data from these adsorption experiments, and the pseudo-second-order well explains all-adsorption kinetics. Most contacts between molecules, electrostatic interactions, π-π interactions, hydrogen bonding, and entrapment in the modified CAG network were used to carry out the DZ, AMX, and CV adsorption on the GAC-PEG. The retrievability of the prepared adsorbent was successfully investigated in studies up to two cycles without loss of adsorption efficiency, and it was shown that it can be efficiently separated.

Vonoprazan-Amoxicillin Dual Therapy With Different Amoxicillin Administration Regimens for Helicobacter pylori Treatment: A Randomized Controlled Trial

BACKGROUND

The effect of preprandial or postprandial administration of amoxicillin on the efficacy of vonoprazan-amoxicillin dual therapy (VA-dual therapy) for Helicobacter pylori treatment has not been studied. It is also unclear whether amoxicillin dosing four times daily is more effective than three times daily. We aimed to investigate the effect of different amoxicillin administration regimens on the efficacy of VA-dual therapy.

MATERIALS AND METHODS

H. pylori-infected subjects were randomly assigned to three groups in a 1:1:1 ratio to receive a 14-day dual therapy consisting of vonoprazan 20 mg twice daily + amoxicillin 1000 mg three times daily before meals (BM-TID) or 1000 mg three times daily after meals (AM-TID) or 750 mg four times daily after meals (AM-QID). H. pylori eradication rates, adverse events rates, compliance, and antibiotic resistance were compared.

RESULTS

Between May 2021 to April 2023, 327 subjects were enrolled. The eradication rates of BM-TID, AM-TID, and AM-QID dual therapy were 88.1%, 89.9%, and 93.6% in intention-to-treat (ITT) analysis, 90.6%, 94.2%, and 99.0% in modified ITT (MITT) analysis, and 90.4%, 94.1%, and 99.0% in per-protocol (PP) analysis. Although there was non-inferiority between BM-TID and AM-TID, as well as between AM-TID and AM-QID, AM-QID was significantly more effective than BM-TID. There were no significant differences in adverse event rates, compliance, and antibiotic resistance among the three groups.

CONCLUSIONS

Postprandial administration and the increased frequency of administration of amoxicillin may contribute to a better efficacy of VA-dual therapy, especially for rescue therapy. All VA-dual therapy in our study could achieve good efficacy for first-line treatment.

TRIAL REGISTRATION

clinicaltrials.gov: NCT05901051.

Exploring the Therapeutic Potential of High Dose Co-amoxiclav (1 gm) in Different Clinical Conditions: A Review

Amoxicillin/clavulanate (co-amoxiclav) is a widely used antibiotic in community healthcare settings, combining amoxicillin and clavulanate potassium to combat β-lactamase-producing bacteria. Despite its extensive use, limited pharmacokinetic/pharmacodynamic data support current dosing guidelines. This review explores the significance of high-dose co-amoxiclav (875 mg/125 mg) in treating various infections amidst rising antibiotic resistance. A comprehensive narrative literature review was conducted using MEDLINE, PubMed, and Google Scholar, focusing on co-amoxiclav 875 mg/125 mg from 1992 to 2024. Keywords included "Co-amoxiclav 875mg/125mg," "amoxicillin 875mg," "Co-amoxiclav dosing," "pharmacology," "PK," and "safety." Studies on non-safety aspects, those on cost-effectiveness, non-English articles, and those without full-text access were excluded. Clinical efficacy studies demonstrate the effectiveness of co-amoxiclav (875 mg/125 mg) in treating conditions such as cutaneous actinomycosis, actinomycetoma, lower respiratory tract infections, acute bacterial maxillary sinusitis, and community-acquired pneumonia. Comparative studies reveal similar or superior efficacy of co-amoxiclav (875 mg/125 mg) compared to other dosing regimens and antibiotics such as clindamycin, cefaclor, cefuroxime, and ciprofloxacin. Safety and tolerability assessments indicate that co-amoxiclav is generally well-tolerated, with common mild-to-moderate gastrointestinal side effects. In summary, co-amoxiclav 1 gm remains a crucial antibiotic with optimized dosing regimens enhancing clinical outcomes while addressing resistance challenges.

Synergistic bactericidal activity of a novel dual β-lactam combination against methicillin-resistant Staphylococcus aureus

OBJECTIVES

MRSA is a major cause of hospital-acquired and community-acquired infections. Treatment options for MRSA are limited because of the rapid development of β-lactam resistance. Combining antibiotics offers an affordable, time-saving, viable and efficient approach for developing novel antimicrobial therapies. Both amoxicillin and cefdinir are oral β-lactams with indications for a wide range of bacterial infections and mild side effects. This study aimed to investigate the in vitro and in vivo efficacy of combining these two β-lactams against MRSA strains.

METHODS

Fourteen representative prevalent MRSA strains with diverse sequence types (STs) were tested with a combination of amoxicillin and cefdinir, using chequerboard and time-kill assays. The Galleria mellonella larvae infection model was used to evaluate the in vivo efficacy of this dual combination against the community-acquired MRSA (CA-MRSA) strain USA300 and the hospital-acquired MRSA (HA-MRSA) strain COL.

RESULTS

The chequerboard assay revealed a synergistic activity of the dual amoxicillin/cefdinir combination against all tested MRSA strains, with fractional inhibitory concentration index (FICI) values below 0.5 and at least a 4-fold reduction in the MICs of both antibiotics. Time-kill assays demonstrated synergistic bactericidal activity of this dual combination against the MRSA strain USA300 and strain COL. Moreover, in vivo studies showed that the administration of amoxicillin/cefdinir combination to G. mellonella larvae infected with MRSA strains significantly improved the survival rate up to 82%, which was comparable to the efficacy of vancomycin.

CONCLUSIONS

In vitro and in vivo studies indicate that the dual combination of amoxicillin/cefdinir demonstrates a synergistic bactericidal efficacy against MRSA strains of various STs. Further research is needed to explore its potential as a treatment option for MRSA infections.

Idiosyncratic Drug-Induced Liver Injury and Amoxicillin-Clavulanate: Spotlight on Gut Microbiota, Fecal Metabolome and Bile Acid Profile in Patients

Several hepatic disorders are influenced by gut microbiota, but its role in idiosyncratic drug-induced liver injury (iDILI), whose main causative agent is amoxicillin-clavulanate, remains unknown. This pioneering study aims to unravel particular patterns of gut microbiota composition and associated metabolites in iDILI and iDILI patients by amoxicillin-clavulanate (iDILI-AC). Thus, serum and fecal samples from 46 patients were divided into three study groups: healthy controls (n = 10), non-iDILI acute hepatitis (n = 12) and iDILI patients (n = 24). To evaluate the amoxicillin-clavulanate effect, iDILI patients were separated into two subgroups: iDILI non-caused by amoxicillin-clavulanate (iDILI-nonAC) (n = 18) and iDILI-AC patients (n = 6). Gut microbiota composition and fecal metabolome plus serum and fecal bile acid (BA) analyses were performed, along with correlation analyses. iDILI patients presented a particular microbiome profile associated with reduced fecal secondary BAs and fecal metabolites linked to lower inflammation, such as dodecanedioic acid and pyridoxamine. Moreover, certain taxa like Barnesiella, Clostridia UCG-014 and Eubacterium spp. correlated with significant metabolites and BAs. Additionally, comparisons between iDILI-nonAC and iDILI-AC groups unraveled unique features associated with iDILI when caused by amoxicillin-clavulanate. In conclusion, specific gut microbiota profiles in iDILI and iDILI-AC patients were associated with particular metabolic and BA status, which could affect disease onset and progression.

Ingestion of amoxicillin-clavulanic acid at therapeutic concentration during blood meal impacts Aedes aegypti microbiota and dengue virus transmission

Dengue virus (DENV), mainly transmitted by Aedes aegypti mosquitoes, is the most prevalent arbovirus worldwide, representing a public health problem in tropical and subtropical countries. In these areas, antibiotic consumption rises which may impact both mosquito microbiota and dengue transmission. Here, we assessed how the ingestion by Ae. aegypti of therapeutic concentrations of amoxicillin-clavulanic Acid association (Amox/Clav), a broad-spectrum antibiotic used to treat febrile symptoms worldwide, impacted its microbiota. We also evaluated whether simultaneous ingestion of antibiotic and DENV impacted Ae. aegypti ability to transmit this virus. We found that Amox/Clav ingestion impacted microbiota composition in Ae. aegypti and we confirmed such impact in field-collected mosquitoes. Furthermore, we observed that Amox/Clav ingestion enhanced DENV dissemination and transmission by this mosquito at 21 days post-DENV exposure. These findings increase our understanding of factors linked to human hosts that may influence dengue transmission dynamics in regions with mass-drug administration programs.

Phytochemical Analysis and Anti-Biofilm Potential That Cause Dental Caries from Black Cumin Seeds (Nigella sativa Linn.)

The oral cavity is an excellent place for various microorganisms to grow. Spectrococcus mutans and Spectrococcus sanguinis are Gram-negative bacteria found in the oral cavity as pioneer biofilm formers on the tooth surface that cause caries. Caries treatment has been done with antibiotics and therapeutics, but the resistance level of S. mutans and S. sanguinis bacteria necessitates the exploration of new drug compounds. Black cumin (Nigella sativa Linn.) is known to contain secondary metabolites that have antioxidant, antibacterial, anti-biofilm, anti-inflammatory and antifungal activities. The purpose of this review article is to present data on the potential of Nigella sativa Linn seeds as anti-biofilm. This article will discuss biofilm-forming bacteria, the resistance mechanism of antibiotics, the bioactivity of N. sativa extracts and seed isolates together with the Structure Activity Relationship (SAR) review of N. sativa compound isolates. We collected data from reliable references that will illustrate the potential of N. sativa seeds as anti-biofilm drug.

A Comprehensive Study to Determine the Residual Elimination Pattern of Major Metabolites of Amoxicillin-Sulbactam Hybrid Molecules in Rats by UPLC-MS/MS

Amoxicillin and sulbactam are widely used in animal food compounding. Amoxicillin-sulbactam hybrid molecules are bicester compounds made by linking amoxicillin and sulbactam with methylene groups and have good application prospects. However, the residual elimination pattern of these hybrid molecules in animals needs to be explored. In the present study, the amoxicillin-sulbactam hybrid molecule (AS group) and a mixture of amoxicillin and sulbactam (mixture group) were administered to rats by gavage, and the levels of the major metabolites of amoxicillin, amoxicilloic acid, amoxicillin diketopiperazine, and sulbactam were determined by UPLC-MS/MS. The residue elimination patterns of the major metabolites in the liver, kidney, urine, and feces of rats in the AS group and the mixture group were compared. The results showed that the total amount of amoxicillin, amoxicilloic acid, amoxicillin diketopiperazine, and the highest concentration of sulbactam in the liver and kidney samples of the AS group and the mixture group appeared at 1 h after drug withdrawal. Between 1 h and 12 h post discontinuation, the total amount of amoxicillin, amoxicilloic acid, and amoxicillin diketopiperazine in the two tissues decreased rapidly, and the elimination half-life of the AS group was significantly higher than that in the mixture group (p < 0.05); the residual amount of sulbactam also decreased rapidly, and the elimination half-life was not significantly different (p > 0.05). In 72 h urine samples, the total excretion rates were 60.61 ± 2.13% and 62.62 ± 1.73% in the AS group and mixture group, respectively. The total excretion rates of fecal samples (at 72 h) for the AS group and mixture group were 9.54 ± 0.26% and 10.60 ± 0.24%, respectively. These results showed that the total quantity of amoxicillin, amoxicilloic acid, and amoxicillin diketopiperazine was eliminated more slowly in the liver and kidney of the AS group than those of the mixture group and that the excretion rate through urine and feces was essentially the same for both groups. The residual elimination pattern of the hybrid molecule in rats determined in this study provides a theoretical basis for the in-depth development and application of hybrid molecules, as well as guidelines for the development of similar drugs.

Oral versus intravenous antibiotic treatment of moderate-to-severe community-acquired pneumonia: a propensity score matched study

Community-acquired Pneumonia (CAP) guidelines generally recommend to admit patients with moderate-to-severe CAP and start treatment with intravenous antibiotics. This study aims to explore the clinical outcomes of oral antibiotics in patients with moderate-to-severe CAP. We performed a nested cohort study of an observational study including all adult patients presenting to the emergency department of the Haga Teaching Hospital, the Netherlands, between April 2019 and May 2020, who had a blood culture drawn. We conducted propensity score matching with logistic and linear regression analysis to compare patients with moderate-to-severe CAP (Pneumonia Severity Index class III-V) treated with oral antibiotics to patients treated with intravenous antibiotics. Outcomes were 30-day mortality, intensive care unit admission, readmission, length of stay (LOS) and length of antibiotic treatment. Of the original 314 patients, 71 orally treated patients were matched with 102 intravenously treated patients. The mean age was 73 years and 58% were male. We found no significant differences in outcomes between the oral and intravenous group, except for an increased LOS of + 2.6 days (95% confidence interval 1.2-4.0, p value < 0.001) in those treated intravenously. We conclude that oral antibiotics might be a safe and effective treatment for moderate-to-severe CAP for selected patients based on the clinical judgement of the attending physician.

Endophytes: a uniquely tailored source of potential antibiotic adjuvants

Multidrug microbial resistance is risking an annual loss of more than 10 million people' lives by 2050. Solutions include the rational use of antibiotics and the use of drugs that reduce resistance or completely obliterate them. Here endophytes come to play due to their high-yield production and inherent nature to produce antimicrobial molecules. Around 40%, 45% and 17% of antibacterial agents were obtained from fungi, actinomycetes, and bacteria, respectively, whose secondary metabolites revealed effectiveness against resistant microbes such as MRSA, MRSE, and Shigella flexneri. Endophyte's role was not confined to bactericidal effect but extended to other mechanisms against MDR microbes, among which was the adjuvant role or the "magic bullets". Scarce focus was given to antibiotic adjuvants, and many laboratories today just screen for the antimicrobial activity without considering combinations with traditional antibiotics, which means real loss of promising resistance combating molecules. While some examples of synthetic adjuvants were introduced in the last decade, the number is still far from covering the disused antibiotics and restoring them back to clinical use. The data compiled in this article demonstrated the significance of quorum sensing as a foreseen mechanism for adjuvants from endophytes secondary metabolites, which call for urgent in-depth studies of their molecular mechanisms. This review, comprehensively and for the first time, sheds light on the significance of endophytes secondary metabolites in solving AMR problem as AB adjuvants.

WHO's essential medicines and AWaRe: recommendations on first- and second-choice antibiotics for empiric treatment of clinical infections

The WHO Model List of Essential Medicines (EML) prioritizes medicines that have significant global public health value. The EML can also deliver important messages on appropriate medicine use. Since 2017, in response to the growing challenge of antimicrobial resistance, antibiotics on the EML have been reviewed and categorized into three groups: Access, Watch, and Reserve, leading to a new categorization called AWaRe. These categories were developed taking into account the impact of different antibiotics and classes on antimicrobial resistance and the implications for their appropriate use. The 2023 AWaRe classification provides empirical guidance on 41 essential antibiotics for over 30 clinical infections targeting both the primary health care and hospital facility setting. A further 257 antibiotics not included on the EML have been allocated an AWaRe group for stewardship and monitoring purposes. This article describes the development of AWaRe, focussing on the clinical evidence base that guided the selection of Access, Watch, or Reserve antibiotics as first and second choices for each infection. The overarching objective was to offer a tool for optimizing the quality of global antibiotic prescribing and reduce inappropriate use by encouraging the use of Access antibiotics (or no antibiotics) where appropriate. This clinical evidence evaluation and subsequent EML recommendations are the basis for the AWaRe antibiotic book and related smartphone applications. By providing guidance on antibiotic prioritization, AWaRe aims to facilitate the revision of national lists of essential medicines, update national prescribing guidelines, and supervise antibiotic use. Adherence to AWaRe would extend the effectiveness of current antibiotics while helping countries expand access to these life-saving medicines for the benefit of current and future patients, health professionals, and the environment.

Role of β-Lactamase Inhibitors as Potentiators in Antimicrobial Chemotherapy Targeting Gram-Negative Bacteria

Since the discovery of penicillin, β-lactam antibiotics have commonly been used to treat bacterial infections. Unfortunately, at the same time, pathogens can develop resistance to β-lactam antibiotics such as penicillins, cephalosporins, monobactams, and carbapenems by producing β-lactamases. Therefore, a combination of β-lactam antibiotics with β-lactamase inhibitors has been a promising approach to controlling β-lactam-resistant bacteria. The discovery of novel β-lactamase inhibitors (BLIs) is essential for effectively treating antibiotic-resistant bacterial infections. Therefore, this review discusses the development of innovative inhibitors meant to enhance the activity of β-lactam antibiotics. Specifically, this review describes the classification and characteristics of different classes of β-lactamases and the synergistic mechanisms of β-lactams and BLIs. In addition, we introduce potential sources of compounds for use as novel BLIs. This provides insights into overcoming current challenges in β-lactamase-producing bacteria and designing effective treatment options in combination with BLIs.

Incidence of amoxycillin-clavulanic acid associated hepatotoxicity in an Australian children's hospital

OBJECTIVES

Amoxycillin/clavulanic acid is the most common antimicrobial cause of drug-induced liver injury in adults. It is a less common cause of severe drug-related hepatotoxicity in children despite its frequent use. We studied the incidence, characteristics and predictive factors for amoxycillin/clavulanic acid hepatoxicity in children.

DESIGN

Retrospective cohort study of children who received oral or intravenous amoxycillin/clavulanic acid at a quaternary children's hospital over a 5-year period. Children were included if they had liver function tests (LFTs) determined at baseline, during and within 3 months after the treatment course. Causality was assessed using the Naranjo criteria for adverse drug reactions and Roussel Uclaf Causality Assessment Method.

RESULTS

Of 3271 children prescribed amoxycillin/clavulanic acid, 374 were included. Forty-nine (13%) had LFT abnormalities related to amoxycillin/clavulanic acid. Fourteen (3.6%) fulfilled Common Terminology Criteria for Adverse Events (CTCAE) grade 2 criteria with clinically significant hepatotoxicity. Age <2 years, sepsis, post-gastrointestinal surgical indications, prolonged treatment course of >7 days and higher cumulative amoxycillin (>10 g) and clavulanic acid dose (>1 g) were predictive of hepatotoxicity. The median time to resolution of LFT abnormalities was 4 weeks (range 3-7).

CONCLUSIONS

The incidence of amoxycillin/clavulanic acid related LFT abnormalities (CTCAE Grade 2 or above) in children was 3.6%. A prolonged treatment course >7 days, high cumulative amoxycillin (10 g) and clavulanic acid (>1 g) doses, those aged <2 years, and patients with sepsis or post-gastrointestinal surgery were predictive of a higher likelihood of abnormal LFTs. LFT monitoring should be considered in children receiving ≥7 days of treatment, particularly in those with other predisposing factors.

Adverse Drug Reactions Resulting From the Use of Chiral Medicines Amoxicillin, Amoxicillin-Clavulanic Acid, and Ceftriaxone: A Mixed Prospective-Retrospective Cohort Study

The use of chiral medicines (possessing center(s) of asymmetric carbon) may cause adverse drug reactions (ADRs). The safety assurance of these medicines is critical. We aimed to evaluate registered and commonly used anti-infective chiral medicines circulating in the Tanzanian market to establish their safety profile to protect public health. A mixed prospective-retrospective cohort study was conducted to assess the safety profile of amoxicillin, amoxicillin-clavulanic acid and ceftriaxone injection. ADRs causality assessment was conducted by using World Health Organization (WHO)-Algorithm criteria. Data were collected from 7 tertiary hospitals: Muhimbili National Hospital (MNH), Kilimanjaro Christian Medical Centre (KCMC), Bugando Medical Centre (BMC), Ligula Referral-Regional Hospital (LRRH), Kitete Referral-Regional Hospital (KRRH), Dodoma Referral-Regional Hospital (DRRH), and Mbeya Zonal-Referral Hospital (MZRH). Data were supplemented by those recorded in the WHO-Vigiflow/VigiLyze database within the same monitoring period. Data were analyzed using STATA version-15. The results were considered statistically significant when P < .05. A total of 2522 patients were enrolled in hospitals: MNH (499), KCMC (407), BMC (396), LRRH (387), KRRH (345), DRRH (249), and MZRH (239). Among those, 1197 (47.5%) were treated with ceftriaxone, 585 (23.2%) amoxicillin and 740(29.3%) amoxicillin-clavulanic acid. Out of those, 102 (4.5%) experienced adverse events (AEs), 49 (48%) were due to ceftriaxone, 37 (36.3%) amoxicillin-clavulanic acid and 16 (15.7%) amoxicillin (P-value .012). A total of 443 participants from the enrolled and WHO-Vigiflow/VigiLyze database were experienced with ADRs. The ADRs affected mainly gastro-intestinal system 234 (53%), skin and subcutaneous tissue 85 (19%), nervous system 49 (11%), respiratory thoracic 22 (5%), and general disorders 18(4%). In this study, approximately 90% of reported AEs were ADRs possible-related to the monitored medicines, with few plausible and certain. Ceftriaxone injection caused more ADRs. Amoxicillin-clavulanic acid was associated with more ADRs than amoxicillin alone. The safety profile of these medicines is still maintained; however, comprehensive monitoring of ADRs is recommended to improve patient safety and enhance overall treatment outcomes.

B. vulgatus ameliorates high-fat diet-induced obesity through modulating intestinal serotonin synthesis and lipid absorption in mice

The consumption of high-fat diets (HFD) and an imbalance in gut microbiome are linked to obesity. However, the intricate connection between them and the underlying mechanisms involved in lipid digestion and absorption remain largely unclear. This study shows that after 12 weeks of HFD feeding, C57BL/6J mice exhibit two distinct metabolic phenotypes with significant differences in gut microbiota composition. The LOW and LOW FMT group mice with increased Bacteroides are protected from obesity, insulin resistance, and lipid accumulation. Supplementation with B. vulgatus or cholic acid (CA) alleviates HFD-induced obesity and metabolic dysfunction. This is due to the accumulation of lipid droplets and the retention of chyle particles in jejunal epithelial cells, which reduces chyle intake in the jejunal mesentery after HFD. Decreased 5-HT synthesis in the jejunal enterochromaffin cells of these mice, along with reduced chyle intake in the jejunal mesentery after HFD in Tph1△IEC, suggests that intestinal 5-HT is required for host lipid absorption. TRPV1, a calcium-permeable ion channel, mediates the basolateral 5-HT-induced increase of Isc and ion channel open probability. This study uncovers a novel signaling axis of microbiota-metabolite-5-HT and intracellular calcium-dependent lipid absorption, which may serve as the potential therapeutic targets for treating HFD-induced obesity.

Simultaneous monitoring of amoxicillin and paracetamol in synthetic biological fluids using a 3D printed disposable electrode with a lab-made conductive filament

In this work, we are pleased to present for the first time a 3D-printed electrochemical device using a lab-made conductive filament based on graphite (Gr) and polylactic acid (PLA) polymer matrix for the simultaneous detection of amoxicillin (AMX) and paracetamol (PAR). The sensor was properly characterized by scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV). Compared to the commercial glassy carbon electrode (GCE), the superior performance of the 3D-Gr/PLA electrode was verified with a 3.8-fold more favored charge transfer. A differential pulse voltammetry (DPV) method was proposed providing a linear working range of 4 to 12 μmol L-1 for both analytes and a limit of detection (LOD) of 0.80 and 0.51 μmol L-1 for AMX and PAR, respectively. Additionally, repeatability studies (n = 5, RSD < 5.7%) indicated excellent precision, and recovery percentages ranging from 89 to 109% when applied to synthetic human urine, saliva, and plasma samples, attested to the accuracy of the method. The studies also indicate that the sensor does not suffer significant interference from common substances (antibiotics and biomarkers) present in the biological fluids, which makes it a promising analytical tool considering its low-cost, ease of manufacturing, robustness, and electrochemical performance.

What if amoxicillin/clavulanic acid reduces the cisplatin anticancer impact on oral cancer treatment?

Antibiotics-chemotherapeutics combination have become on the table for many cancer treatments. For this reason, we thought that further progress and development of studies to support chemotherapeutic approaches with the use of antibiotics may be beneficial in the clinical field. Cell lines (SCC-15, HTB-41, and MRC-5) were treated with 5-100 μM/ml concentrations of cisplatin (cisp) and amoxicillin/clavulanic acid (amx/cla) with combination (amx/cla-cisp) and alone in three different incubation periods. The all-cells viability was examined with WST-1 and apoptotic activity of the drugs were investigated via cell death ELISA assay kit. The cytotoxic impact of the 100 μM amx/cla-cisp combination was found to be reduced by up to 21.8%, which was significant given that the cytotoxic effect of only cisplatin therapy was 86.1%. Because our findings demonstrated that solo amx/cla therapy have almost no impact on proliferation or death, we focused on the amx/cla-cisp combination effect. It was found that the amx/cla-cisp combination has reduced the apoptotic fragment when comparing with the solely cisp-treated cells. Due to amx/cla-cisp combination on both cells but significantly on SCC-15 recovered the sole cisplatin effect, we believe that there might be a second thought when prescribing antibiotics while treating cancer patients. Not only the antibiotic's type but also the cancer type might interact to lessen the chemotherapeutic agent's impact which is clinically a dilemma to focus on.

Oral and Intravenous Amoxicillin Dosing Recommendations in Neonates: A Pooled Population Pharmacokinetic Study

BACKGROUND

There is a lack of evidence on oral amoxicillin pharmacokinetics and exposure in neonates with possible serious bacterial infection (pSBI). We aimed to describe amoxicillin disposition following oral and intravenous administration and to provide dosing recommendations for preterm and term neonates treated for pSBI.

METHODS

In this pooled-population pharmacokinetic study, 3 datasets were combined for nonlinear mixed-effects modeling. In order to evaluate amoxicillin exposure following oral and intravenous administration, pharmacokinetic profiles for different dosing regimens were simulated with the developed population pharmacokinetic model. A target of 50% time of the free fraction above the minimal inhibitory concentration (MIC) with an MICECOFF of 8 mg/L (to cover gram-negative bacteria such as Escherichia coli) was used.

RESULTS

The cohort consisted of 261 (79 oral, 182 intravenous) neonates with a median (range) gestational age of 35.8 weeks (range, 24.9-42.4) and bodyweight of 2.6 kg (range, 0.5-5). A 1-compartment model with first-order absorption best described amoxicillin pharmacokinetics. Clearance (L/h/kg) in neonates born after 30 weeks' gestation increased with increasing postnatal age (PNA day 10, 1.25-fold; PNA day 20, 1.43-fold vs PNA day 3). Oral bioavailability was 87%. We found that a twice-daily regimen of 50 mg/kg/day is superior to a 3- or 4-times daily schedule in the first week of life for both oral and intravenous administration.

CONCLUSIONS

This pooled population pharmacokinetic description of intravenous and oral amoxicillin in neonates provides age-specific dosing recommendations. We conclude that neonates treated with oral amoxicillin in the first weeks of life reach adequate amoxicillin levels following a twice-daily dosing regimen. Oral amoxicillin therapy could therefore be an adequate, cost-effective, and more patient-friendly alternative for neonates worldwide.

A novel ruthenium-silver based antimicrobial potentiates aminoglycoside activity against Pseudomonas aeruginosa

The rapid dissemination of antibiotic resistance combined with the decline in the discovery of novel antibiotics represents a major challenge for infectious disease control that can only be mitigated by investments in novel treatment strategies. Alternative antimicrobials, including silver, have regained interest due to their diverse mechanisms of inhibiting microbial growth. One such example is AGXX, a broad-spectrum antimicrobial that produces highly cytotoxic reactive oxygen species (ROS) to inflict extensive macromolecular damage. Due to the connections identified between ROS production and antibiotic lethality, we hypothesized that AGXX could potentially increase the activity of conventional antibiotics. Using the gram-negative pathogen Pseudomonas aeruginosa, we screened possible synergistic effects of AGXX on several antibiotic classes. We found that the combination of AGXX and aminoglycosides tested at sublethal concentrations led to a rapid exponential decrease in bacterial survival and restored the sensitivity of a kanamycin-resistant strain. ROS production contributes significantly to the bactericidal effects of AGXX/aminoglycoside treatments, which is dependent on oxygen availability and can be reduced by the addition of ROS scavengers. Additionally, P. aeruginosa strains deficient in ROS detoxifying/repair genes were more susceptible to AGXX/aminoglycoside treatment. We further demonstrate that this synergistic interaction was associated with a significant increase in outer and inner membrane permeability, resulting in increased antibiotic influx. Our study also revealed that AGXX/aminoglycoside-mediated killing requires an active proton motive force across the bacterial membrane. Overall, our findings provide an understanding of cellular targets that could be inhibited to increase the activity of conventional antimicrobials. IMPORTANCE The emergence of drug-resistant bacteria coupled with the decline in antibiotic development highlights the need for novel alternatives. Thus, new strategies aimed at repurposing conventional antibiotics have gained significant interest. The necessity of these interventions is evident especially in gram-negative pathogens as they are particularly difficult to treat due to their outer membrane. This study highlights the effectiveness of the antimicrobial AGXX in potentiating aminoglycoside activities against P. aeruginosa. The combination of AGXX and aminoglycosides not only reduces bacterial survival rapidly but also significantly re-sensitizes aminoglycoside-resistant P. aeruginosa strains. In combination with gentamicin, AGXX induces increased endogenous oxidative stress, membrane damage, and iron-sulfur cluster disruption. These findings emphasize AGXX's potential as a route of antibiotic adjuvant development and shed light on potential targets to enhance aminoglycoside activity.

Treatment of H. pylori infection and gastric ulcer: Need for novel Pharmaceutical formulation

Peptic ulcer disease (PUD) is one of the most prevalent gastro intestinal disorder which often leads to painful sores in the stomach lining and intestinal bleeding. Untreated Helicobacter pylori (H. pylori) infection is one of the major reasons for chronic PUD which, if left untreated, may also result in gastric cancer. Treatment of H. pylori is always a challenge to the treating doctor because of the poor bioavailability of the drug at the inner layers of gastric mucosa where the bacteria resides. This results in ineffective therapy and antibiotic resistance. Current treatment regimens available for gastric ulcer and H. pylori infection uses a combination of multiple antimicrobial agents, proton pump inhibitors (PPIs), H2-receptor antagonists, dual therapy, triple therapy, quadruple therapy and sequential therapy. This polypharmacy approach leads to patient noncompliance during long term therapy. Management of H. pylori induced gastric ulcer is a burning issue that necessitates alternative treatment options. Novel formulation strategies such as extended-release gastro retentive drug delivery systems (GRDDS) and nanoformulations have the potential to overcome the current bioavailability challenges. This review discusses the current status of H. pylori treatment, their limitations and the formulation strategies to overcome these shortcomings. Authors propose here an innovative strategy to improve the H. pylori eradication efficiency.