Epidermidis Research Articles

Characterization of Conjunctival Microflora and Antibiotic Sensitivity Patterns in Patients Undergoing Cataract Surgery

This study aims to characterize the conjunctival flora of patients scheduled for cataract surgery and determine the susceptibility profile of isolated bacteria to several commonly used topical antibiotics. Conjunctival swabs were taken from 44 consecutive patients (25 males, 19 females; mean age of 75.0 ± 12.6 years) who were scheduled for senile cataract surgery at two Italian centers before starting any prophylactic preoperative treatment. Swabs were processed for the detection of the microbial growth and for species identification. Selective culture media were used, and bacteria were identified using the MicroScan Specialty ID Panels (Beckman Coulter®, Brea, CA, USA). Antimicrobial susceptibility for the following antibiotics (netilmicin, tobramycin, ofloxacin, oxacillin, levofloxacin, moxifloxacin, chloramphenicol, cefuroxime, and azithromycin) were assessed using the Kirby–Bauer disk diffusion method. Susceptibility for oxacillin was useful to identify methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE). Among the swabs analyzed, 61.4% showed only saprophytic flora, 30.7% showed only potential pathogenic flora, and 8.0% showed mixed flora. S. epidermidis (20.5%), S. intermedius (18.2%), and S. aureus (14.8%) were the most frequent isolates; MRSA and MRSE accounted for 8.0% and 6.8% of isolates. Less frequently (9%), Gram-negative bacteria such as Pseudomonas fluorescent, Serratia marcescens, Moraxella lacunata, Morganella morgani, and Stenotrophomonas maltophila were detected. All isolated organisms showed an excellent sensitivity to moxifloxacin and chloramphenicol (range 83–100%, range 67–100%, Gram-positive sensitivity for moxifloxacin and chloramphenicol, respectively; 100% Gram-negative sensitivity for both). A significant percentage of the eyes of candidates for surgery presented potential pathogenic flora alone or in association with saprophytic organisms. Staphylococci were the most frequently isolated bacteria. Tobramycin and Ofloxacin, widely used in the ophthalmic field, are confirmed to have a reduced sensitivity in vitro.

Tribulus terrestris Fruit Extract: Bioactive Compounds, ADMET Analysis, and Molecular Docking with Penicillin-Binding Protein 2a Transpeptidase of Methicillin-Resistant Staphylococcus epidermidis.

Tribulus terrestris is a rich source of bioactive molecules and thrives in Mediterranean and desert climate regions worldwide. In this study, Tribulus terrestris methanolic HPLC fractions were evaluated for bioactive compounds and PBP2a transpeptidase inhibitors against methicillin-resistant Staphylococcus epidermidis (MRSE). Among the collected HPLC fractions, F02 of the methanol extract demonstrated potential activity against MRSE01 (15 ± 0.13 mm), MRSE02 (13 ± 0.21 mm), and MRSE03 (16 ± 0.14 mm) isolates. GC-MS analysis of the F02 fraction identified seventeen compounds. Among seventeen compounds, eight have favorable pharmacokinetics and medicinal chemistry; however, on the basis of in silico high water solubility, high GI absorption, blood-brain barrier non-permeability, lack of toxicity, and potential drug-likeness, 1-ethylsulfanylmethyl-2,8,9-trioxa-5-aza-1-sila-bicyclo[3.3.3]undecane and phthalimide, N-(1-hydroxy-2-propyl), were processed for molecular docking. 1-ethylsulfanylmethyl-2,8,9-trioxa-5-aza-1-sila-bicyclo[3.3.3]undecane formed three hydrogen bonds with Ser-452, Thr-584, and Asn-454 residues of the PBP2a transpeptidase. Similarly, phthalimide, N-(1-hydroxy-2-propyl)-formed four hydrogen bonds with Ser-396, Asn-454, Lys-399, and Ser-452 residues of PBP2a transpeptidase. These two compounds are proposed as novel putative PBP2a transpeptidase inhibitors. Further characterization of compounds extracted from Tribulus terrestris may aid in identifying novel PBP2a inhibitory agents for managing MRSE infections.

Mapping Antimicrobial Resistance in Staphylococcus epidermidis Isolates from Subclinical Mastitis in Danish Dairy Cows.

Background/Objectives: Although Staphylococcus epidermidis is a key cause of subclinical mastitis in Danish dairy cows, its sensitivity to antimicrobials remains unexplored. Here, we analyzed sixty S. epidermidis isolates derived from 42 dairy cows across six conventional dairy herds in Denmark. Methods: Phenotypic resistance was measured by antimicrobial susceptibility testing and minimum inhibitory concentration (MIC) analysis, and genotypic resistance was examined through whole-genome sequencing and identification of antimicrobial resistance genes (ARGs). Correspondence between phenotypic and genotypic resistance was then evaluated by Cohen's kappa statistics. Furthermore, the presence of plasmid replicon genes and the strain diversity among the S. epidermidis isolates was investigated to associate these findings with the observed AMR patterns. Results: Results showed that 30/60 isolates (50.0%) were resistant to penicillin phenotypically, while 35/60 (58.3%) were positive for a corresponding blaZ gene (κ = 0.83, p < 0.01). A fosB gene, encoding fosfomycin resistance, was detected in all 60/60 isolates (100.0%), but fosfomycin resistance was not analyzed phenotypically. Based on MIC analysis, 3/60 isolates (5.0%) were multi-drug resistant, showing resistance towards penicillin, erythromycin, and tetracycline. However, in 11/60 genomes (18.3%), ARGs encoding resistance towards ≥3 antimicrobial classes (e.g., beta-lactams, phosphonic acid, tetracyclines, aminoglycosides, macrolides, lincosamides, and fusidane) were detected. Eleven different ARGs were detected among the 60 isolates in total. No methicillin-resistant Staphylococcus epidermidis (MRSE) were recorded. Results further showed that each herd had one primary sequence type (ST) and resistance profile associated with it, and plasmid-mediated horizontal gene transfer of ARGs was indicated This study underscores the importance of routine resistance surveillance and species-specific diagnoses to improve treatment outcomes and ensure prudent use of antimicrobials.

Aktivitas Antijamur Ekstrak Biji Kopi Hijau Robusta (Coffea canephora) Terhadap Candida albicans.

Acne is a disease that can be caused by bacteria, one of which is Staphylococcus epidermidis. Acne can be treated with active compounds derived from natural ingredients such as cucumbers and tomatoes. Gel masks peel off. This study aims to determine the average diameter of the inhibition zone, the difference in the average diameter of the inhibition zone, and the antibacterial activity of the peel-off from a mixture of cucumber (Cucumis sativus) and tomato (Solanum lycopersicum) with a concentration of 5%, 10 %, 15%, 20% against Staphylococcus epidermidis. This experimental study uses a Completely Randomized Design (CRD) consisting of one factor and 6 levels. The results showed that the average diameter of the inhibition zone of the anti-acne peel-off gel mask preparation of cucumber and tomato extracts against Staphylococcus epidermidis at a concentration of 5%, 10%, 15% and 20% were 16.38 mm, respectively. ; 24.88 mm; 29.88 mm and 34.88 mm. There was a significant difference in the average diameter of the inhibition zone of the peel off mixture of cucumber and tomato extracts with a concentration of 5%, 10%, 15%, and 20%; against Staphylococcus epidermidis. gel mask preparation peels off from a mixture of cucumber and tomato extracts against Staphylococcus epidermidis at a concentration of 5%, 10% concentration, 15% concentration and 20% concentration, namely strong, very strong, very strong and very strong. Keywords: staphylococcus epidermidis, gel mask peel-off, cucumber, tomato

Inhibitory effect of andrographolide on the expression of key regulatory genes in Staphylococcus epidermidis biofilm formation.

The purpose of this study was to explore the inhibitory effect of andrographolide on the expression of key regulatory genes involved in the biofilm formation of Staphylococcus epidermidis (SE). Taking the film-producing strain Staphylococcus epidermidis SE1457 as the research object, the effect of andrographolide on the formation of Staphylococcus epidermidis biofilms was analyzed via crystal violet staining, and biofilm models of SE adhesion, aggregation and maturity were established in vitro. RT‒PCR was used to detect the effects of the expression of icaA-, atlE-, aap- and luxS-related genes of andrographolide on biofilm formation in SE. Congo red qualitative test to evaluate the ability of andrographolide to inhibit biofilm formation of Staphylococcus epidermidis. Compared with that of the control group, the light absorption value of the low- and high-concentration andrographolide groups was significantly lower, and the light absorption value of the high-concentration andrographolide group was significantly lower than that of the low-concentration andrographolide group. The levels of key genes involved in the adhesion, aggregation and maturation of icaA, atlE, aap and luxS in group C were greater than those in group B. The biofilm-forming ability of SE in group A was strong, and the colonies were obviously black. The colony in the direction of the arrow in group B was red, and the SE biofilm was inhibited. Most of the colonies in group C were red. SE biofilms were significantly inhibited. Andrographolide inhibits SE biofilm formation, and its mechanism may involve inhibition of the expression of the related genes icaA, atlE, aap and luxS.

Microbiological spectrum of organisms in patients undergoing external ventricular drain insertion at a tertiary care hospital.

To assess the incidence, causative pathogens, and impact of external ventricular drain-related infection on disease prognosis. The observational, cross-sectional study was conducted from September 2022 to March 2023 after obtaining approval from the ethics review board of Shifa International Hospital, Islamabad, Pakistan, and comprised patients having no prior cerebrospinal fluid infection. The patients underwent external ventricular drain administration as part of their treatment. Unneeded antibiotics or cerebrospinal fluid sampling before removing the drain were avoided. External ventricular drain-related infection was defined as pathogenic growth on one or more cerebrospinal fluid culture/sensitivity test post-insertion of the drain. Data was analysed using SPSS 26. Of the 74 patients, 42(56.8%) were males and 32(43.2%) were females. Overall, 25(33.8%) patients were aged 20-50 years. A total of 86 external ventricular drain were inserted for a mean period of 10.77+/-7.42 days (range: 1-40), with a total of 797 catheter days. Hydrocephalus 21(28.4%) and tumours 20(27%) were the most common aetiologies for external ventricular drain, but no significant aetiological risk factors for external ventricular drain-related infection were identified (p>0.05). Overall, 39(52.7%) patients recovered with external ventricular drain removal, and 12(16.2%) needed a shunt. External ventricular drain-related infection developed in 12(16.2%) patients (95% confidence interval: 4.15-4.75), having external ventricular drain for a mean period of 14.92+/-10.5 days (range 5-40) and 179 total catheter days. Coagulase-negative staphylococcus epidermidis was found in 4(33.3%) and it was sensitive to vancomycin, followed by Klebsiella pneumoniae and Pseudomonas aeruginosa 2(16.7%) each, and they were sensitive to amikacin and colistin, respectively. External ventricular drain-related infection was associated with poor outcomes (p=0.04), a longer intensive care unit stay (p<0.05), a longer hospital stay (p<0.05), and a longer external ventricular drain in-situ (p=0.05). Aseptic external ventricular drain placement and its early removal could avoid external ventricular drain-related infections.

A Contemporary Picture of Coagulase-Negative Staphylococcal Endocarditis: A Nationwide GAMES Cohort Study.

Coagulase-negative staphylococci (CoNS) are an increasingly common cause of infective endocarditis (IE) and lack recent data from large studies. Our aim was to describe the epidemiology, clinical characteristics, and outcomes of staphylococcal IE in a contemporary nationwide cohort study, while comparing coagulase-negative staphylococcal IE (CoNSIE) to IE from Staphylococcus aureus (SAIE), and among IE caused by Staphylococcus epidermidis (SE), S.lugdunensis (SL), and other CoNS. We completed a post hoc analysis of a prospectively collected cohort of 4,567 consecutive definitive IE episodes from 44 Spanish centers between 2008 and 2022 (GAMES ["Grupos de Apoyo al Manejo de la Endocarditis Infecciosa en España"] cohort). A total of 842 cases of CoNSIE were compared with 1,109 cases of SAIE. Additionally, 647 episodes caused by SE were compared with 54 caused by SL and 109 caused by 9 other known CoNS species. Multivariate analyses were performed to investigate prognostic factors for in-hospital and 1-year mortality. Staphylococci accounted for 1,951 (42.7%) episodes of IE. The predominant CoNS etiology was SE (76.8%), followed by SL (6.4%), S.capitis (3.5%), S.haemolyticus (3.2%), S.hominis (3.2%), S.warneri (1.5%), and 5 other species. CoNSIE showed a distinct clinical profile from SAIE (older age, higher rates of prior heart disease, aortic and prosthetic valve involvement, nosocomial acquisition, methicillin resistance, intracardiac complications, and cardiac surgery), while in-hospital mortality was higher in SAIE (32.8% vs 37.1%; P = 0.049), with no significant differences in 1-year mortality. S.lugdunensis displayed a shorter course of infection and higher rates of leaflet perforation/rupture than S.epidermidis and other CoNS, but cardiac surgery rates (60.4% vs 61.1% vs 56.0%; P = 0.850), as well as in-hospital (33.1% vs 37.0% vs 27.5%; P = 0.540) and 1-year mortality rates were high and similar in all groups. Septic shock, heart failure, and cardiac surgery (protective) were consistently identified as independent prognostic factors, whereas none of the staphylococcal species were independently associated with mortality. Last, each 5-year study period was independently associated with a reduction in staphylococcal in-hospital and 1-year mortality. CoNSIE was a relatively common (18.4%) and life-threatening entity with particularities by species yet generally high rates of surgery and mortality, although its prognosis improved over time.

Surveillance of Antimicrobial Resistance Bacteria in a Healthcare Facility at an Industrial Site in Saudi Arabia.

This study aimed to perform surveillance and identify antimicrobial resistance (AMR) in the most common pathogenic bacteria in a healthcare facility in Rabigh City, Saudi Arabia. A total of 1,933 samples were processed from patients during the study period from January 2022 to June 2022. Identification and antimicrobial susceptibility of the cultured isolates were performed using the MicroScan system. Out of the 1,933 tested samples, 11.1% (n = 214) were positive for bacterial growth. A relatively higher percentage of isolates was recovered from patients older than 50 years (55.9%). Gram-negative bacteria (67.3%) were significantly more prevalent than Gram-positive bacteria (32.7%). The Gram-negative pathogenic bacteria comprised mainly Escherichia coli and Klebsiella pneumoniae, followed by Pseudomonas aeruginosa. Staphylococ-cus epidermidis and coagulase-negative staphylococci were found at relatively high abundance in Gram-positive bacteria. Increased resistance to carbapenem antibiotics was observed in K. pneumoniae. In Gram-positive bac¬teria, > 50% of the isolates of S. epidermidis were resistant to 13 tested antimicrobial agents. This study provided an overview of the distribution of pathogenic bacteria and antimicrobial susceptibility of the prevalent Gram-negative and Gram-positive pathogenic bacteria in a major healthcare facility in Saudi Arabia. It highlights the importance of continuously monitoring AMR bacteria in healthcare settings to ensure the effective use of antibiotics for treatment.

Clinical features of infective endocarditis affecting cardiac implantable electronic devices

Abstract Introduction Infective endocarditis (IE) is a serious condition with high rates of serious complications and mortality. Furthermore, implantation of cardiac electronic devices (peacemakers, ICD, CRT) has been increasing in recent years, with technique-associated infections being one of the main adverse events. Our goal was to analise clinical features of IE as associated with cardiac implantable electronic devices (IE-CIED) and its prognostic impact. Methods Prospective study of a cohort of patients diagnosed with IE in our centre from 1987 to 2022. A comparative analysis was performed between patients with IE not associated with cardiac implantable electronic devices (group 1) and those who did (group 2). Clinical, microbiological, echocardiographic and therapeutic variables were analysed and the prognostic impact was evaluated in terms of mortality. Results 569 patients were analysed, of which 540 (94,9%) belonged to group 1, while 29 (5,1%) belonged to group 2. The mean age was higher in group 2 (65,1 years ±12,9 vs 55,7 years ± 18,7; p=0,011) with male predominance in both populations (67.5% overall). Patients with IE-CIED had a higher proportion of staphylococcus aureus (48.3% vs 19.7%; p&amp;lt;0.001) and staphylococcus epidermidis (34.5% vs 15.6%; p&amp;lt;0.001) infections; nosohusial endocarditis (56.5% vs 20.9%; p&amp;lt;0.001); and underlying heart disease (89.7% vs 67.3%; p=0.012). Furthermore, these patients had a higher proportion of tricuspid valve involvement (18.2% vs 81.8%; p&amp;lt;0.001). Regarding the approach, a higher percentage of surgery was performed in patients with IE-CIED (75.9% vs52.7%; p=0.015). On the other hand, patients with IE not associated to cardiac implantable electronic devices had a higher prevalence of cardiac complications (51.5%vs25.7%;p=0.003), defined as valvular rupture or perforation, pseudoaneurysm, abscess or intracardiac fistula; and central nervous system complications (17.2%vs2.9%;p=0.29). No significative differences were found in terms of echocardiographic findings compatibles with IE, nor were there any differences in severe complications or early, late or total mort ality. Conclusions Infective endocarditis affecting cardiac implantable electronic devices is associated to higher prevalence of staphylococci, underlying heart disease and less involvement of the left heart chambers. Surgery was used to a greater extent in this patients. This entity does not imply a worse prognosis in terms of severe complications or mortality.Table 1.Proportion of IE-CIEDTable 2.Microbiology, mortality

Evaluation of a nucleic acid amplification system, GENECUBE, for rapid detection of staphylococcal nuc and mecA in blood culture samples

ObjectiveThis study determined whether the GENECUBE rapid nucleic acid amplification test could directly detect nuc and mecA genes in clinical blood culture samples of Staphylococcus and various other pathogens. MethodsBetween September 2020 and December 2021, 537 blood culture samples from 192 patients with suspected bacteremia were tested using conventional assays (MicroScan WalkAway96 or VITEK 2 systems) and GENECUBE nuc and mecA assays. Isolates from samples with discrepant results between the conventional and GENECUBE assays were further evaluated using MALDI-TOF mass spectrometry, disk diffusion testing using cefoxitin, broth microdilution testing using oxacillin, and sequencing for mecA. Bacterial solutions containing a mixture of methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus epidermidis (MRSE) were prepared to evaluate the limit of detection (LOD) of mecA. ResultsUsing conventional assays as the reference, the sensitivity, specificity, and positive and negative predictive values (95 % confidence interval) of GENECUBE were 100 % (96.8–100 %), 100 % (99.1–100 %), 100 % (96.8–100 %), and 100 % (99.1–100 %), respectively, for nuc detection and 100 % (96.1–100 %), 98.9 % (97.4–99.6 %), 94.9 % (88.5–98.3 %), and 100 % (99.2–100 %), respectively, for mecA detection. Sequencing analysis of five samples identified as methicillin-sensitive staphylococci using conventional assays and methicillin-resistant staphylococci using GENECUBE revealed the presence of methicillin-resistant isolates in all samples. The estimated LOD of mecA was 104 colony-forming units (CFU)/mL of MRSE with GENECUBE, compared with 105 CFU/mL with conventional assays. ConclusionThe GENECUBE assay accurately detected mecA in positive blood culture samples and had higher sensitivity than conventional assays.

Synergistic Effect of Aloe Vera L. Extract Methanolic With Some Antibiotics Against S. Aureus, E-Coli and Klebslia Isolated From the Eye Affected by Inflammation

The current study included the collection of (300) samples from (150) people from patients visiting Balad General Hospital and some private clinics in Balad District - Salah Al-Din Governorate, a sample was taken from both the right and left eyes using special dry and sterile cotton swabs that can be disposed of later, for the period ranging from November 2022 to January 2023, (235) positive samples for bacterial growth were obtained, constituting 78.3% of the total samples collected, positive growth samples were diagnosed depending on their morphological, farming and biochemical properties, and the diagnosis was confirmed for a number of them using the Vitek2 system technology. The results showed obtaining 140 isolates out of a total of (235) positive samples for the Gram stain by (59.6%), while the negative isolates of the Gram stain were (95) isolates and amounted to (40.4%) of the total isolates, S. aureus was 27.65% and E-coli 10.63%, while Klebsiella was 8.51% of the total bacterial isolates isolated from the eye, including (staphylococcus aureus, staphylococcus epidermidis, Bacillus, Streptococcus Viridians, Diphtheria, Pseudomonas aeruginosa, Klebsiella, E-coli, Neisseria). The results showed the synergistic effect of the alcoholic extract (methanol) of the aloe vera plant (Aloe Vera L.) with antibiotics a significant effect compared to methanol alcoholic extract alone, the results of the study also showed that the antibiotic Ciprofloxone synergistically with the alcoholic extract methanolic of the aloe vera plant (Aloe Vera L.) it had the highest effect already synergistically with most of the bacterial species under study.

Comparison of bloodstream infections due to Corynebacterium striatum, MRSA, and MRSE

BackgroundCorynebacterium striatum (C. striatum), a common skin and mucosal colonizer, is increasingly considered as an opportunistic pathogen causing bloodstream infections (BSIs). This study aims to investigate the clinical features and outcomes of C. striatum-BSI.MethodsWe included hospitalized cases with C. striatum-positive blood cultures from January 2014 to June 2022 and classified them into C. striatum-BSI group and contamination group; Clinical characteristics, treatments, and outcomes were compared between the C. striatum-BSI group and contamination group, Methicillin-resistant Staphylococcus aureus (MRSA)-BSI and Methicillin-resistant Staphylococcus epidermidis (MRSE)-BSI.ResultsFifty-three patients with positive C. striatum blood cultures were identified. Among them, 25 patients were classified as C. striatum-BSI, with 21 as contamination cases. And 62 cases of MRSA-BSI and 44 cases of MRSE-BSI were identified. Compared to the contaminated group, the C. striatum-BSI group had a shorter time to positivity of blood cultures (27.0 h vs. 42.5 h, P = 0.011). C. striatum-BSI group had a longer time to positivity (27 h) when compared to both the MRSA (20 h) and MRSE groups (19 h) (p < 0.05). Appropriate therapy within 24 h of BSI onset was significantly lower in the C. striatum group (28%) compared to the MRSA (64.5%) and MRSE (65.9%) groups (p < 0.005). The 28-day mortality was higher in the C. striatum group (52.0%) compared to the MRSA (25.8%) and MRSE (18.2%) groups. ConclusionsGiven the distinct characteristics of C. striatum-BSI, including a longer time to positivity than other Gram-positive bacteria and higher mortality rates, we suggest prescribing early appropriate antibiotics if C. striatum-BSI is suspected.

Self-Assembling and Pore-Forming Peptoids as Antimicrobial Biomaterials.

Bacterial infections have been a serious threat to mankind throughout history. Natural antimicrobial peptides (AMPs) and their membrane disruption mechanism have generated immense interest in the design and development of synthetic mimetics that could overcome the intrinsic drawbacks of AMPs, such as their susceptibility to proteolytic degradation and low bioavailability. Herein, by exploiting the self-assembly and pore-forming capabilities of sequence-defined peptoids, we discovered a family of low-molecular weight peptoid antibiotics that exhibit excellent broad-spectrum activity and high selectivity toward a panel of clinically significant Gram-positive and Gram-negative bacterial strains, including vancomycin-resistant Enterococcus faecalis (VREF), methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE), Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Tuning the peptoid side chain chemistry and structure enabled us to tune the efficacy of antimicrobial activity. Mechanistic studies using transmission electron microscopy (TEM), bacterial membrane depolarization and lysis, and time-kill kinetics assays along with molecular dynamics simulations reveal that these peptoids kill both Gram-positive and Gram-negative bacteria through a membrane disruption mechanism. These robust and biocompatible peptoid-based antibiotics can provide a valuable tool for combating emerging drug resistance.

Biosynthesis Silver nanoparticles by using Supernatant staphylococcus epidermidis and antibacterial Activity of resistant pathogenic bacteria

Biosynthesis Silver nanoparticles by using Supernatant staphylococcus epidermidis and antibacterial Activity of resistant pathogenic bacteria

Comment on Ma et al.’s “The Preventive Effect of Gentamicin in the Irrigating Solution on Endophthalmitis Caused by Methicillin-Resistant Staphylococcus epidermidis After Phacoemulsification with Intraocular Lens Implantation in Rabbits”

ABSTRACT In their recent publication, the authors explored the preventive effect of gentamicin in the irrigating solution on endophthalmitis caused by methicillin-resistant Staphylococcus epidermidis (MRSE) after phacoemulsification with intraocular lens (IOL) implantation in rabbits. This letter commends the authors for their innovative approach and discusses the potential of chitosan-based intraocular lenses as a future solution for reducing the incidence of endophthalmitis. Chitosan’s natural antibacterial properties, coupled with its capacity for sustained drug release and surface modification, make it a promising material for IOLs. This letter highlights recent advancements and suggests areas for further research to fully realize the potential of chitosan-based IOLs in ocular surgery.

1004 Urgent Explant of Infected Aortic Stent Graft in a Patient with Kidney Transplant Using Biological Aortoiliac Reconstruction and a Temporary Axillo-Femoral Perfusion Shunt: 6-Year Follow-Up and Literature Review

Abstract Background Written consent obtained for case report. A 59-year-old male who was 3-months post-EVAR repair under immunosuppression for kidney transplantation and anti-retroviral HIV treatment presented to ED in 2017 with abdominal pain and fever. CTAP revealed pyelonephritis in renal allograft. Blood cultures were positive for staphylococcus epidermidis. PETCT showed high-intensity uptake around endograft. Urgent explant of endograft and insitu biological aorto-biiliac graft reconstruction with bench prepared bilateral long saphenous veins were performed. Results The predicted challenges were locating source of infection, immunosuppressed state, and allograft preservation. Dacron graft was used as temporary perfusion shunt (left axillary artery to right superficial femoral artery) for renal allograft on right external iliac vessels. Endograft was removed via rooftop incision with visceral rotation. Supra-celiac and supra-superior mesenteric artery clamping times were 15 and 35 minutes. The source of infection was from infected appendix proximal to graft with erosion of right external iliac artery resulting in appendectomy in the same operation. Following 12-weeks of OPAT antibiotic-therapy, repeat PETCT revealed low-grade uptake around aortic graft and inflammatory markers were back to baseline. At 6 years in 2023, patient remains clinically well with ∼20% allograft function. Maintaining kidney allograft perfusion in the setting of elective non-infected aortic graft explant was previously reported, but with ENROUTE system (Rasheed et al., 2018). Conclusions The satisfactory long-term outcomes discussed here demonstrated with MDT planning involving vascular surgery, infectious diseases, renal medicine and patient, explant of infected graft with insitu biological graft reconstruction in renal transplant patients presenting with complex aortic-graft infection is feasible.

Ceftaroline Fosamil as a Potential Treatment for Central Nervous System Infections in Children

Abstract Ceftaroline has been reported to show efficacy in limited adult clinical case studies including a report of a patient with a methicillin-resistant Staphylococcus aureus (MRSA) infection of a ventriculopleural shunt, and in 2 reports for use as a salvage therapy in a case of an epidural abscess infected with MRSA, as well as a case of methicillin-resistant Staphylococcus epidermidis (MRSE) ventriculostomy-related infection. The pharmacokinetic (PK) and pharmacodynamic (PD) properties of ceftaroline in healthy adults and neurosurgical patients have been assessed to develop population PK models used to perform simulations to evaluate the probability of target attainment of different ceftaroline dosing regimens for central nervous system (CNS) infections. Results from the simulations indicated that the penetration of ceftaroline into the cerebrospinal fluid was dependent on the degree of meningeal inflammation, suggesting that inflammation associated with infection would provide adequate antibiotic exposure, similar to other β-lactam antibiotics. Ceftaroline has a potential, unique role as a β-lactam antibiotic in the treatment of MRSA and coagulase negative staphylococci causing CNS infections as an alternative to vancomycin, the current standard of care. Support for treatment of CNS infections may be derived from further cerebrospinal fluid PK studies followed by PK/PD modeling prior to the conduct of prospective phase 2/3 clinical studies aimed at assessing the efficacy and safety of ceftaroline for the treatment of pediatric CNS infections. Ceftaroline's penetration enhanced by meningeal inflammation suggests that the drug could be a candidate to treat MRSA CNS infections.

Inhibition of staphylococcus epidermidis Biofilm Formation in Response to Purified Phytochemical Antimicrobial Materials

Inhibition of staphylococcus epidermidis Biofilm Formation in Response to Purified Phytochemical Antimicrobial Materials

In response to bacteria, neutrophils release extracellular vesicles capable of initiating thrombin generation through DNA-dependent and independent pathways.

Neutrophils release extracellular vesicles, and some subsets of neutrophil-derived extracellular vesicles are procoagulant. In response to Staphylococcus aureus, neutrophils produce extracellular vesicles that associate electrostatically with neutrophil extracellular traps. DNA in neutrophil extracellular traps is procoagulant, but whether neutrophil extracellular vesicles produced during bacterial challenge have similar activity is unknown. Given that extracellular vesicle activity is agonist and cell-type dependent and coagulation contributes to sepsis, we hypothesized that sepsis-causing bacteria increase production of neutrophil-derived extracellular vesicles, as well as extracellular vesicle-associated DNA, and intact extracellular vesicles and DNA cause coagulation. We recovered extracellular vesicles from neutrophils challenged with S. aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa and measured associated DNA and procoagulant activity. Extracellular vesicles from S. aureus-challenged neutrophils, which were previously characterized, displayed dose-dependent procoagulant activity as measured by thrombin generation in platelet-poor plasma. Extracellular vesicle lysis and DNase treatment reduced thrombin generation by 90% and 37%, respectively. S. epidermidis, E. coli, and P. aeruginosa also increased extracellular vesicle production and extracellular vesicle-associated extracellular DNA, and these extracellular vesicles were also procoagulant. Compared to spontaneously released extracellular vesicles, which demonstrated some ability to amplify factor XII-dependent coagulation in the presence of an activator, only extracellular vesicles produced in response to bacteria could initiate the pathway. S. aureus and S. epidermidis extracellular vesicles had more surface-associated DNA than E. coli and P. aeruginosa extracellular vesicles, and S. aureus and S. epidermidis extracellular vesicles contributed to initiation and amplification of thrombin generation in a DNA-dependent manner. However, DNA on E. coli or P. aeruginosa extracellular vesicles played no role, suggesting that neutrophils release procoagulant extracellular vesicles, which can activate the coagulation cascade through both DNA-dependent and independent mechanisms.

In Vivo Comparison of the Efficacy and Duration of Local Antibiotics on Smooth, Textured and Polyurethane Implant Surfaces

BackgroundCapsular contracture is one of the most common complications after breast surgery involving silicone implants. The most likely cause of this condition is biofilm formation. In this study, the efficacy of local antibiotherapy against biofilm formation on implant surfaces was investigated.MethodsThirty-six rats were divided into six groups. Three pockets were created on the dorsum of each rat, and 1 × 2 cm implant surface samples from smooth, polyurethane and textured implants were randomly placed into pockets. All samples were inoculated with staphylococcus epidermidis. In groups 1-2-3, inoculated samples were placed into the pockets and removed after 1, 6 and 24 h, respectively. In groups 4-5-6, inoculated samples immersed with rifamycin were placed and removed after 1, 6 and 24 h, respectively. Bacterial load was measured with plate count method.ResultsBacterial load was lower in groups 4-5-6 than in groups 1-2-3 (p < 0.05). In groups 4-5-6, bacterial load was lower for polyurethane than for textured surfaces at all time points (1, 6 and 24 h; p < 0.05). Again, in groups 4-5-6, bacterial load was lower for smooth than for textured surfaces at 24 h (p < 0.05). In groups 4-5-6, bacterial load was lower for polyurethane than for smooth surfaces at all time points, but difference was not statistically significant (1, 6 and 24 h; p < 0.05).ConclusionThe results suggest that local antibiotic therapy was effective in reducing the bacterial load on all surfaces. The effectiveness of local rifamycin on the polyurethane surface was higher, and the duration of activity was longer than other surfaces.No Level Assigned This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of contents or the online Instructions to Authors www.springer.com/00266.