Methicillin-resistant Staphylococci Research Articles

Atopic dermatitis pediatric patients show high rates of nasal and intestinal colonization by methicillin-resistant Staphylococcus aureus and coagulase-negative staphylococci

BackgroundAtopic dermatitis (AD) patients have high rates of colonization by Staphylococcus aureus, which has been associated with worsening of the disease. This study characterized Staphylococcus spp isolates recovered from nares and feces of pediatric patients with AD in relation to antimicrobial susceptibility, staphylococcal cassette chromosome mec (SCCmec) type, presence of pvl genes and clonality. Besides, gut bacterial community profiles were compared with those of children without AD.ResultsAll 55 AD patients evaluated had colonization by Staphylococcus spp. Fifty-three (96.4%) patients had colonization in both clinical sites, whereas one patient each was not colonize in the nares or gut. Staphylococcus aureus was identified in the nostrils and feces of 45 (81.8%) and 39 (70.9%) patients, respectively. Methicillin-resistant Staphylococcus spp. isolates were found in 70.9% of the patients, and 24 (43.6%) had methicillin-resistant S. aureus (MRSA). S. aureus (55.6%) and S. epidermidis (26.5%) were the major species found. The prevalent lineages of S. aureus were USA800/SCCmecIV (47.6%) and USA1100/SCCmecIV (21.4%), and 61.9% of the evaluated patients had the same genotype in both sites. Additionally, gut bacterial profile of AD patients exhibits greater dissimilarity from the control group than it does among varying severities of AD.ConclusionsHigh rates of nasal and intestinal colonization by S. aureus and methicillin-resistant staphylococci isolates were found in AD patients. Besides, gut bacterial profiles of AD patients were distinctly different from those of the control group, emphasizing the importance of monitoring S. aureus colonization and gut microbiome composition in AD patients.

Comparative Antimicrobial Activity of Securidaca longipedunculata (Fresen) Extracts on Selected Human Pathogens

The escalating trend of microbial resistance has become a pressing global concern, challenging the effectiveness of antimicrobial agents in treating infections. This study was aimed at evaluating the antimicrobial activity of the n-hexane, ethyl acetate, and methanol extracts of Securidaca longipedunculata against selected human pathogens. The antimicrobial screening against bacterial pathogens- (e.g., Methicillin-resistant staphylococcus aureus, Vancomycin-resistant Enterococci, Staphylococcus aureus, Staphylococcus feacalis, Escherichia coli, Salmonella typhimurium, Pseudomans fluorescens and Klebsiella pneumonieae) and fungal pathogens (which includes Candida albicans, Candida krusei, Aspergillus niger, Aspergillus fumigates, and Microsporum canis) was performed using agar well diffusion and broth dilution methods. The results demonstrated significant antimicrobial activity, with higher efficacy against S. aureus. Susceptibility test results showed that the extract inhibited the growth of all the test organisms (bacteria and fungi) with a mean zone of inhibition range of 18-29 mm, with the exception of VRE, S. typhimurium, P. fluorescens, C. krusei and M. canis in all the three extracts, while Hexane extract showed no inhibition against E. coli and A. niger. The standard drugs sparfloxacin and ciprofloxacin (500 µg/cm3) had zone of inhibition ranging from 28 - 40 mm. While the antifungal drugs fluconazole and fulcin exhibited zone of inhibition ranging from 27 mm to 34 mm. The Minimum inhibitory concentration (MIC) for the extracts ranges from 62.5 - 250µg/cm3, while the Minimum Bactericidal/Fungicidal Concentrations (MBC/MFC) range from 250 - 500 µg/cm3, respectively. The ethyl acetate extracts possessed higher antimicrobial activity among the three extracts tested against S. Aureus. The findings suggest that S. longipedunculata leaves hold promise as a natural source of antimicrobial agents, warranting further exploration for potential therapeutic applications.

Antibiotic Resistance to Molecules Commonly Prescribed for the Treatment of Antibiotic-Resistant Gram-Positive Pathogens: What Is Relevant for the Clinician?

Antibiotic resistance in Gram-positive pathogens is a relevant concern, particularly in the hospital setting. Several antibiotics are now available to treat these drug-resistant pathogens, such as daptomycin, dalbavancin, linezolid, tedizolid, ceftaroline, ceftobiprole, and fosfomycin. However, antibiotic resistance can also affect these newer molecules. Overall, this is not a frequent phenomenon, but it is a growing concern in some settings and can compromise the effectiveness of these molecules, leaving few therapeutic options. We reviewed the available evidence about the epidemiology of antibiotic resistance to these antibiotics and the main molecular mechanisms of resistance, particularly methicillin-resistant Sthaphylococcus aureus, methicillin-resistant coagulase-negative staphylococci, vancomycin-resistant Enterococcus faecium, and penicillin-resistant Streptococcus pneumoniae. We discussed the interpretation of susceptibility tests when minimum inhibitory concentrations are not available. We focused on the risk of the emergence of resistance during treatment, particularly for daptomycin and fosfomycin, and we discussed the strategies that can be implemented to reduce this phenomenon, which can lead to clinical failure despite appropriate antibiotic treatment. The judicious use of antibiotics, epidemiological surveillance, and infection control measures is essential to preserving the efficacy of these drugs.

Bioactive VS4-based sonosensitizer for robust chemodynamic, sonodynamic and osteogenic therapy of infected bone defects

BackgroundMost bone defects caused by bone disease or trauma are accompanied by infection, and there is a high risk of infection spread and defect expansion. Traditional clinical treatment plans often fail due to issues like antibiotic resistance and non-union of bones. Therefore, the treatment of infected bone defects requires a strategy that simultaneously achieves high antibacterial efficiency and promotes bone regeneration.ResultsIn this study, an ultrasound responsive vanadium tetrasulfide-loaded MXene (VSM) Schottky junction is constructed for rapid methicillin-resistant staphylococcus aureus (MRSA) clearance and bone regeneration. Due to the peroxidase (POD)-like activity of VS4 and the abundant Schottky junctions, VSM has high electron–hole separation efficiency and a decreased band gap, exhibiting a strong chemodynamic and sonodynamic antibacterial efficiency of 94.03%. Under the stimulation of medical dose ultrasound, the steady release of vanadium element promotes the osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). The in vivo application of VSM in infected tibial plateau bone defects of rats also has a great therapeutic effect, eliminating MRSA infection, then inhibiting inflammation and improving bone regeneration.ConclusionThe present work successfully develops an ultrasound responsive VS4-based versatile sonosensitizer for robust effective antibacterial and osteogenic therapy of infected bone defects.

Low prevalence of bacteria harbouring the main transferable genes coding for β-lactams resistance in ovine bulk tank milk produced in Central Italy

Sheep farming for milk production is an important sector of the Italian agricultural industry. Italy has a significant annual sheep milk production, which amounted to 477.000 ton in 2021 and almost exclusively employed for cheeses production. The aim of this work was to evaluate the prevalence of beta-lactams-resistant bacteria (methicillin-resistant staphylococci and Gram-negative bacteria) in bulk tank ovine milk collected from 97 farms located in central Italy (Tuscany and Lazio). Samples were screened for the presence of resistant microorganisms employing selective media, bacteria were identified by 16 S rRNA gene sequencing and tested for susceptibility for different beta-lactams (penicillins, carbapenems, cephalosporins, as well as beta lactams association with beta-lactamase inhibitors). Resistant microorganisms were subjected to PCR for the detection of the main transferable gene coding for beta-lactams resistance mechanisms spread among Gram-positive and Gram-negative bacteria. A low prevalence of methicillin resistant staphylococci (4%) and methicillin resistant Staphylococcus aureus (1%) in bulk tank milk from sheep herds raised in Central Italy was highlighted. This resistance was related to the presence of mecA gene in S. aureus and coagulase negative staphylococci. All the tested samples resulted negative for the presence of bacteria able to produce carbapenemases or ESBLs due to the presence of some of the main mobile genetic determinants in their genomes and targeted in this study. Most of the phenotypic resistance observed were instead related to the common presence of psychrotrophic bacteria in bulk tank milk belonging to Stenothrophomonas spp. which harboured L1 and L2 genes coding for inducible β-lactamases located on the bacterial chromosome. In conclusion, a low prevalence of bacteria resistant to β-lactams due to the presence of horizontally transferable genes was detected, suggesting a low selective pressure for resistant microrganisms whitin this farming system.

Prevalence and anti-microbial resistance of Staphylococcus spp. isolated from the environment and veterinary personnel in a Spanish veterinary teaching hospital.

Methicillin-resistant Staphylococcus (MRS) bacteria, including methicillin-resistant S. aureus and methicillin-resistant S. pseudintermedius (MRSP), pose a significant threat in veterinary medicine, given their potential for zoonotic transmission and their implications for companion animals and humans' health. This study aimed to assess the prevalence of MRS and anti-microbial resistance patterns at a university clinical hospital in Madrid, Spain. Samples were collected from both the environment and hospital staff at Veterinary Clinical Hospital of Alfonso X el Sabio University. Anti-microbial susceptibility assays, molecular detection of mecA gene and genetic relationships among the identified bacterial strains were performed. The study revealed an MRS prevalence of 1.50% in environmental samples, with MRSP accounting for 0.75% of the cases. Genetically related MRSP strains were found in different hospital areas. Among hospital staff, there was a MRS prevalence of 14.03%, including S. pseudintermedius and S. epidermidis strains. Antibiogram tests revealed multi-drug resistance among MRSP strains. Additionally, methicillin-resistant coagulase-negative staphylococci were isolated, suggesting potential cross-species transmission. This study underscores the presence of MRS in a veterinary clinical hospital, highlighting the significance of infection control through the implementation of protective measures, stringent hygiene practices among personnel and in the environment and responsible use of antibiotics. Further research is necessary to assess MRS incidence in animal patients and explore geographical variations, enhancing our understanding of MRS in veterinary medicine and addressing its challenges.

Occurrence, genetic diversity, and antimicrobial resistance of methicillin-resistant Staphylococcus spp. in hospitalized and non-hospitalized cats in Brazil.

Methicillin-resistant Staphylococci (MRS) cause infections at various sites and exhibit multidrug resistance. Despite their importance in veterinary medicine, only little is known about Staphylococcus spp. colonizing and infecting cats. Therefore, in this study, we aimed to isolate and identify Staphylococcus spp. colonizing hospitalized and non-hospitalized domestic cats and analyze their antimicrobial resistance profiles, genetic diversity, and risk factors associated with MRS colonization. A total of 218 oral and axillary swabs were obtained from 109 cats, including 77 non-hospitalized and 32 hospitalized cats. After plating on selective media, the isolates were identified via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and rpoB and 16S rRNA gene sequencing. Subsequently, antimicrobial sensitivity of the strains was assessed, and they were screened for mecA gene. Methicillin-resistant S. haemolyticus (MRSH) isolates were subjected to multilocus sequence typing, whereas methicillin-resistant S. pseudintermedius (MRSP) and S. felis isolates were subjected to whole genome sequencing. S. felis was most commonly isolated from non-hospitalized cats (28.1%), whereas S. pseudintermedius and MRS were commonly isolated from hospitalized cats (25%). MRSH isolates from hospitalized animals were classified as ST3. The identified MRSP strains belonged to two well-known sequence types, ST551 and ST71. Moreover, antimicrobial use (p = 0.0001), hospitalization (p = 0.0141), and comorbidities (p = 0.002) were associated with increased MRS prevalence in cats.

Transcutaneous Osseointegrated Prosthesis Systems (TOPS) for Rehabilitation After Lower Limb Loss: Surgical Pearls.

Transcutaneous Osseointegrated Prosthesis Systems (TOPS) for Rehabilitation After Lower Limb Loss: Surgical Pearls.

Abundance and diversity of methicillin-resistant bacteria from bathroom surfaces at workplaces using CHROMagar media, 16S, and dnaJ gene sequence typing.

University campus communities consist of dynamic and diverse human populations originated from different regions of the country or the world. Their national/global movement to and from campus may contribute to the spread and buildup of methicillin-resistant (MR) bacteria, including MR Staphylococci (MRS) on high-touch surfaces, sinks, and toilets. However, studies on MR bacteria contamination of surfaces, sinks, and toilets are scarce in workplaces outside of healthcare settings. Hence, little is known whether university communities contaminate campus bathrooms by MR bacteria. This study evaluated the abundance, identity, and phylogenetics of MR bacteria grown on CHROMagar MRSA media from bathrooms at workplaces. We collected 21 sink and 21 toilet swab samples from 10 buildings on campus and cultured them on CHROMagar MRSA media, extracted DNA from MR bacteria colonies, sequenced PCR products of 16S and dnaJ primers, determined the sequence identities by BLAST search, and constructed a phylogenetic tree. Of 42 samples, 57.1% (24/42) harbored MR bacteria. MR bacteria were more prevalent on the sink (61.9%) than in the toilet (52.2%) and in male bathrooms (54.2%) than in female bathrooms (41.7%). The colony count on the bathroom surfaces of 42 samples varied in that 42.9% (18/42), 33.3, 14.3, and 9.5% of samples harbored 0, 100, and > 1000 MR bacteria colonies, respectively. Of MR bacteria sequenced, BLAST search and phylogenetic analysis showed that Staphylococcus accounted for 60% of the MR bacteria and the rest were non-Staphylococci. Of Staphylococcus carrying MR (n = 15), 53.3% were S. hemolyticus followed by S. lugdunensis (26.7%), S. epidermidis (8%), and a newly discovered S. borealis in 2020 (4%). Of non-Staphylococci MR bacteria, 20% accounted for Sphingomonas koreensis. Campus bathrooms serve as a reservoir for diverse bacteria carrying MR, which pose a direct risk of infection and a potential source of horizontal gene transfer. To reduce the health risk posed by MR bacteria in high traffic areas such as bathrooms additional environmental monitoring and improved decontamination practices are needed.

Newly designed nanoparticle-drug delivery systems against Staphylococcus aureus infection: a systematic review.

A nanoparticle-drug delivery system against Staphylococcus aureus, especially Methicillin-resistant staphylococcus aureus, has been recently proposed as an alternative pathway therapy. Methicillin-resistant staphylococcus aureus is resistance to many antibiotics, making it a a threat to human life, especially for older and immunocompromised people. Treatment of Multidrug-resistant staphylococcus aureus is considered an urgent need. A variety of kinds of nanoparticle-drug delivery systems with different compositions, and biological properties have been extensively investigated against Staphylococcus aureus. This review summarizes the novel nanoparticle-drug delivery systems against Staphylococcus aureus. These nanoparticle-drug delivery systems could reduce antibiotic resistance and minimize side effects of the antibiotics. Also, they can deliver a high concentration of the drugs and eliminate the bacteria in a specific and targeted site of infection. Despite these benefits of nanoparticle-drug delivery systems, the cytotoxicity, stress oxidative, genotoxicity, and inflammation that may occur in vivo and in vitro should not be ignored. Therefore, we need a better knowledge of the pharmacological properties and safety concerns of nanoparticle-drug delivery systems. The limitations of each nanoparticle-drug delivery system with high therapeutic potential have to be considered for further design.

Zinc deficiency enhances sensitivity to influenza A associated bacterial pneumonia in mice.

Although zinc deficiency (secondary to malnutrition) has long been considered an important contributor to morbidity and mortality of infectious disease (e.g. diarrhea disorders), epidemiologic data (including randomized controlled trials with supplemental zinc) for such a role in lower respiratory tract infection are somewhat ambiguous. In the current study, we provide the first preclinical evidence demonstrating that although diet-induced acute zinc deficiency (Zn-D: ~50% decrease) did not worsen infection induced by either influenza A (H1N1) or methicillin-resistant staph aureus (MRSA), Zn-D mice were sensitive to the injurious effects of superinfection of H1N1 with MRSA. Although the mechanism underlying the sensitivity of ZnD mice to combined H1N1/MRSA infection is unclear, it was noteworthy that this combination exacerbated lung injury as shown by lung epithelial injury markers (increased BAL protein) and decreased genes related to epithelial integrity in Zn-D mice (surfactant protein C and secretoglobins family 1A member 1). As bacterial pneumonia accounts for 25%-50% of morbidity and mortality from influenza A infection, zinc deficiency may be an important pathology component of respiratory tract infections.

Recovery of Methicillin Resistant Staphylococci from Public Vehicles in Kathmandu

Objectives: The purpose of this study was to determine the extent of staphylococcal contamination in public vehicles in Kathmandu and to determine the antibiotic susceptibility pattern of the isolates. Methods: This cross-sectional study was conducted from December 2022 to May 2023 in the Microbiological laboratory of Padma Kanya Multiple Campus, Kathmandu. A total of 120 swab (sterile cotton swab moistened with sterile normal saline) samples were collected by gently rubbing the surfaces from 19 different micro-buses during the time of heavy passenger flow (office time) and transported to the laboratory maintaining a cold chain. Staphylococcus aureus and Coagulase negative Staphylococci (CoNS) were identified by their characteristic yellow pigmented colonies on Mannitol Salt Agar (MSA) and the ability of S. aureus to produce coagulase enzyme. Kirby-Bauer disc diffusion method was employed to test the antibiotic susceptibility pattern of isolates. MRSA were identified on the basis of the zone of inhibition (<21 mm diameter) against Cefoxitin 30mcg disc. Results: Out of 41 Staphylococcal isolates, 46.36% were S. aureus, among which 84.21% exhibited methicillin resistance (MRSA). All Coagulase Negative Staphylococci (CoNS) isolates (n=22) were resistant to methicillin (MRCoNS). MRSA and MRCoNS isolates were also resistant to antibiotics like Penicillin and Erythromycin. Conclusion: This study reports relatively high occurrence of MRSA in environmental samples, predominantly in areas frequently touched by people indicating the possibility of easy spread of these organisms and subsequent opportunistic infections.

Survey the proportion and antibiotic sensitivity of methicillin-resistant staphylococcus aureus among patients in Danang Oncology Hospital

In this study, 134 patients including 80 adult men and 54 women treated at Danang Oncology Hospital from January 2019 to July 2021 had specimen culture results found Staphylococcus aureus was investigated. All study patient data was collected according to an established uniform form on Microsoft Excel spreadsheet software and processed by Python programming language. We found that 76.1% of patients infected with S. aureus during this time were MRSA. Of which, 100% MRSA and MSSA isolates were resistant to Amoxicillin, 61.2% to Cefuroxime. Multi-resistance and broad-spectrum multi-resistance to other antibiotics belonging to the Carpapenem, Quinolone and Aminoglycoside groups were recorded in most isolated S. aureus. The results showed that S. aureus causing bacterial infection at Danang Oncology Hospital during the survey period had a high antibiotic resistance rate.

Searching for Antimicrobial-Producing Bacteria from Soils through an Educational Project and Their Evaluation as Potential Biocontrol Agents.

Antimicrobial resistance (AMR) is a serious threat to public health due to the lack of effective drugs to combat infectious diseases, which generates the need to search for new antimicrobial substances. In this study, the potential of soil as a source of antimicrobial-producing bacteria (APB) was investigated and the importance of the connection between education and science was emphasized, using service-learning methodologies. Sixty-one soil samples were collected, and 1220 bacterial isolates were recovered. Eighteen of these isolates showed antimicrobial activity against at least 1 of the 12 indicator bacteria tested (including multidrug-resistant and relevant pathogens). The 18 APB were identified by MALDI-TOF and 6 different genera (Bacillus, Brevibacillus, Lysinobacillus, Peribacillus, Streptomyces, and Advenella) and 10 species were identified. The 18 APB were tested for antifungal activity against four phytopathogenic fungi (Botritis cynerea, Lecanicillium fungicola, Trichoderma harzianum, and Cladobotryum mycophilum). Moreover, the antibiotic susceptibility of APB was tested using the disk-diffusion method as well as their β-hemolytic activity (important safety criteria for potential future applications). A total of 10 of the 18 APB were able to inhibit at least 50% of indicator bacteria tested, including methicillin-resistant Staphylococcus aureus (MRSA), among others. A total of 4 of the 18 APB (3 Bacillus pumilus and 1 Bacillus altitudinis) showed inhibitory activity against two of the four fungal pathogens tested (B. cinerea and L. fungicola), as well as against 5-7 of the 12 bacterial pathogen indicators; these 4 isolates showed susceptibility to the antibiotics tested and lacked β-hemolytic activity and were considered promising APB for use as potential biocontrol agents. In addition, one Brevibacillus laterosporus strain had activity against 83% of indicator bacteria tested including Escherichia coli, MRSA and other methicillin-resistant staphylococci, as well as vancomycin-resistant enterococci (but not against fungi). These results show that soil is a source of APB with relevant antibacterial and antifungal activities, and also emphasize the importance of education and science to raise public awareness of the AMR problem and the strategies to control it.

Microbiology of Infective Endocarditis in United States Veterans - Association Between Causative Organism and Short- and Long-Term Outcomes.

Previous studies have elucidated the relationship between causative organism and outcomes in infective endocarditis, however this relationship has not been studies in United States Veterans. The aim of this manuscript is to evaluate the association between causative organism and short-term and long-term outcomes in United States (US) Veterans with infective endocarditis (IE) requiring surgical management between 2010-2020. We analyzed 489 patients with surgically treated IE from the Veterans Affairs (VA) Surgical Quality Improvement Program and the VA Informatics and Computing Infrastructure databases. Patients were divided into groups using causative organism identified from blood or intraoperative cultures - Staphylococcus, Streptococcus, Gram-negative rods, Enterococcus, Polymicrobial, and Unknown/Culture Negative. Other identified organisms were excluded from analysis. Cox proportional hazard models were used to calculate risk for stroke/transient ischemic attack (TIA), myocardial infarction (MI), and death based on group. The models were adjusted for covariates using backward elimination. Continuous variables were compared using ANOVA or Kruskal-Wallis H tests, and categorical variables were compared using Chi square tests. Mean follow-up was 4.0 ± 6.3 years. Gram negative rods (GNRs) were associated with greater risk of long-term mortality (adjusted hazard ratios (aHR) 2.15, 95% CI: 1.20-3.86, p = 0.01). Enterococcus was associated with long-term risk of MI (aHR 2.05, 95% CI: 1.07-3.94, p = 0.03). Resistant organisms, such as methicillin-resistant staphylococcus aureus, were associated with long-term risk of MI (aHR 2.51, 95% CI: 1.14-5.45, p = 0.02). Polymicrobial infections were associated with greater risk of perioperative complications, including prolonged mechanical ventilation (48 hrs) (aHR 1.76, 95% CI: 1.05-2.97, p = 0.034), tracheostomy (aHR 5.64, 95% CI: 2.35-13.55, p < 0.001), and prolonged ICU stay (5 days) (aHR 1.39, 95% CI: 1.01-1.91, p = 0.043). In US Veterans, polymicrobial infections had notably worse perioperative outcomes but similar long-term outcomes in comparison to monomicrobial infections. GNR infections were associated with increased long-term mortality. Enterococcus and resistant organisms were associated with increased long-term risk of MI. Polymicrobial infections were associated with greater risk of perioperative complications, including prolonged mechanical ventilation, tracheostomy, and prolonged ICU stay.

Radiology Department: A Potential Source of Multidrug-Resistant Microorganisms: A Cross-Sectional Study at Tertiary Hospital, Palestine.

Globally, healthcare facilities face a great challenge in the form of hospital-acquired infections (HAIs). Aside from the morbidity and mortality they cause, these illnesses are also extremely costly. Research on infection transmission in the medical field has been considerable, but not so much in the radiology department. This study aims to identify the presence of multidrug-resistant (MDR) microbes on surfaces that are frequently touched in computed tomography (CT), magnetic resonance imaging (MRI), ultrasound (US), plain X-ray examination rooms, and portable radiography that are susceptible to contamination as well as to investigate the potential dangers of contracting MDR organisms to patients and healthcare providers. Materials and Method. In this study, 160 swab samples were collected from the radiology department during May and June 2022. Samples were obtained from 80 predefined surfaces twice within and outside of CT and MRI examination rooms as well as from US and plain X-ray machines and portable X-ray machines. Samples were taken at 7:00 a.m. using cotton swabs following the regular cleaning procedure. Bacterial colony-forming units (CFUs) per square centimeter were calculated after swabbing a 100 cm2 surface. Nearly all of the surfaces tested had bacterial CFUs. The highest contamination rate was found on keyboards ranging from (1.2-8) CFU/cm2, the sides of patient tables (1.2-20) CFU/cm2, knee coil (2.4-3) CFU/cm2, and patient leg supports (1.2-8) CFU/cm2. A noticeable increase in the contamination was noticed in June compared to May, and this was consistent with the increase in the number of isolated patients in the hospital, the workload in the radiology department, and the number of patients referred to the hospital. In our study, none of the examined sites showed contamination with MDR Gram-negative bacteria such as extended-spectrum beta-lactamases producing Enterobacterales (ESPL) or Carbapenemase-producing Enterobacterales (CPE). On the other hand, methicillin-resistant Staphylococcus (MRS), vancomycin-resistant Staphylococcus (VRS), and vancomycin-resistant Enterococcus (VRE) were detected. All of the radiology department equipment and sites could be a source of bacterial infection including MDR, so the obligatory and committed disinfection protocol must be revised and implemented in the morning and between patients.

Prevalence and Antibiotic Resistance of Bacteria Isolated from Cerebrospinal Fluid of Neurosurgical Patients in Malang, Indonesia

Background: Central nervous system infections are a critical concern in neurosurgical practice, often leading to severe complications and prolonged hospital stays. Understanding the prevalence and antibiotic resistance patterns of the bacteria causing these infections is essential for effective patient management. This study aims to investigate the prevalence and antibiotic resistance profiles of bacteria isolated from cerebrospinal fluid in neurosurgical patients in Malang, Indonesia. Materials and Methods: A retrospective analysis was conducted to investigate the positive cerebrospinal fluid (CSF) cultures in patients who underwent craniotomy within the period of January 2019 to December 2021. The gathered data encompassed the identification of etiological agents and the determination of their respective antimicrobial susceptibilities. Data analysis was performed on a total of 33 individuals, with 67 isolates out of 239 patients and 515 CSF culture samples. Results: The preponderant microorganism identified in the sample was coagulase-negative Staphylococci, with a majority exhibiting methicillin resistance, commonly referred to as methicillin-resistant coagulase-negative Staphylococci (MRCoNS). All specimens exhibited susceptibility to both vancomycin and tigecycline. Klebsiella pneumoniae, a Gram-negative bacterium, was identified as the predominant etiological agent and exhibited resistance to a substantial proportion of the antimicrobial agents tested, specifically 13 out of the 16 antimicrobials evaluated. Conclusions: The sensitivity rates of ceftriaxone and meropenem were found to be 0% and 100%, respectively. The predominant bacteria is MRCoNS, which is completely susceptible to tigecycline, vancomycin, linezolid, and nitrofurantoin. Extended-spectrum beta-lactamase-producing Klebsiella pneumoniae is difficult to treat, especially in central nervous system infections when antimicrobials are scarce.

Bacteriological Profile and Antibiogram of Isolates Causing Bloodstream Infection in Children

Objective: (1) To identify and characterize bacterial isolates causing blood stream infection in children. (2) To determine the antibiotic sensitivity pattern of isolates obtained. Materials And Methods: Study design: Descriptive study. Study population: Blood samples collected from pediatric patients aged upto 12 years who are admitted in Government Medical College Kottayam, with clinical features of blood stream infection. Sampling methodology: The sample size of suspected blood stream infection is 345. All pediatric patients with clinical features suggestive of blood stream infection in the study period satisfying inclusion and exclusion criteria will be included in the study. The identification of bacterial pathogens and antimicrobial susceptibility tests were done by conventional and automated methods like VITEK system. Results: Out of 345 study sample population, 46 were culture positive, of which 21(45.7%) were Gram negative isolates and 20(43.4%) were Gram positive. Major isolates obtained were Klebsiella spp (15%), Methicillin Resistant Coagulase negative Staphylococci (15%), followed by Staphylococcus aureus (13%), Coagulase negative Staphylococci (8%) and Acinetobacter baumannii (8%). Klebsiella pneumoniae was resistant to most of the antibiotics tested except meropenem. All isolates of Coagulase negative Staphylococci and Staphylococcus aureus were susceptible to vancomycin and linezolid. Conclusion: Gram negative organisms were predominant pathogens in blood stream infections. Klebsiella pneumoniae, Coagulase negative Staphylococci, Staphylococcus aureus were the most commonly isolated pathogens. Amikacin along with the third generation cephalosporins should be used for empirical treatment of Gram negative sepsis. Vancomycin and linezolid can be used for Gram positive pathogens.

Near-infrared-responsive nanoplatforms integrating dye-sensitized upconversion and heavy-atom effect for enhanced photodynamic therapy efficacy

The development of near-infrared (NIR)-responsive upconversion nanoplatforms for photodynamic therapy (PDT) has attracted considerable attention in recent years, but is still limited by the low PDT efficacy. Herein, we designed and synthesized a NIR-responsive nanoplatform through the integration of lanthanide-doped upconversion nanoparticles (UCNPs), Pt-decorated porphyrin metal-organic frameworks (PMOFs) and NIR dye IR808 into a core-shell structure for highly efficient antibacterial PDT. The PMOF shell can function not only as a photosensitizer to absorb the upconversion luminescence (UCL) of UCNPs for singlet oxygen (1O2) generation, but also as a porous host material for loading of IR808. Remarkably, we demonstrated that the heavy-atom effect of Pt(II) can simultaneously enhance the intersystem crossing (S1→T1) efficiencies of the IR808 and the porphyrin ligand Pt-TCPP, resulting in the enhancement of dye-triplet-sensitized UCL of UCNPs and 1O2 production capacity of the photosensitizer. As a result, the proposed nanoplatform exhibited excellent 1O2 production and a significant bactericidal activity against methicillin-resistant Staphylococcus aureus (MRSA) with 5.27 log10 (> 99.999%) killing efficacy. These findings will pave the way for designing highly efficient PDT nanoplatforms and accelerate their biomedical applications.

The effect of enterocin A/P dipeptide on growth performance, glutathione-peroxidase activity, IgA secretion and jejunal morphology in rabbits after experimental methicillin-resistant Staphylococcus epidermidis P3Tr2a Infection

The increasing frequency of methicillin-resistant (MR) staphylococci in humans and animals need special attention for their difficult treatment and zoonotic character, therefore novel antimicrobial compounds on a natural base against antibiotic-resistant bacteria are requested. Currently, bacteriocins/enterocins present a new promising way to overcome this problem, both in prevention and treatment. Therefore, the preventive and medicinal effect of dipeptide enterocin EntA/P was evaluated against MR Staphylococcus epidermidis SEP3/Tr2a strain in a rabbit model, testing their influence on growth performance, glutathione-peroxidase (GPx) enzyme activity, phagocytic activity (PA), secretory (s)IgA, and jejunal morphometry (JM). Eighty-eight rabbits (aged 35 days, meat line M91, both sexes) were divided into experimental groups S (SEP3/Tr2a strain; 1.0 × 105 CFU/mL; dose 500µL/animal/day for 7 days, between days 14 and 21 to simulate the pathogen attack), E (EntA/P; 50 µL/animal/day, 25,600 AU/mL in two intervals, for preventive effect between days 0 and 14; for medicinal effect between days 28 and 42), E + S (EntA/P + SEP3/Tr2a; preventive effect; SEP3/Tr2a + EntA/P; medicinal effect) and control group (C; without additives). Higher body weight was recorded in all experimental groups (p < 0.001) compared to control data. The negative influence/attack of the SEP3Tra2 strain on the intestinal immunity and environment was reflected as decreased GPx activity, worse JM parameters and higher sIgA concentration in infected rabbits. These results suggest the promising preventive use of EntA/P to improve the immunity and growth of rabbits, as well as its therapeutic potential and protective role against staphylococcal infections in rabbit breeding.