Methicillin-resistant Staphylococci Research Articles

Impact of antibiotic prophylaxis in second-stage surgery in joint prosthesis infection treated with two-stage exchange. A multicenter case-control study.

After two-stage exchange due to prosthetic joint infection (PJI), the new prosthesis carries a high risk of reinfection (RePJI). There isn`t solid evidence regarding the antibiotic prophylaxis in 2nd-stage surgery. The objective of this study is to describe what antibiotic prophylaxis is used in this surgery and evaluate its impact on the risk of developing RePJI. Retrospective multicenter case-control study in Spanish hospitals. The study included cases of PJI treated with two-stage exchange and subsequently developed a new infection. For each case, two controls were included, matched by prosthesis location, center, and year of surgery. The prophylaxis regimens were grouped based on their antibacterial spectrum, and we calculated the association between the type of regimen and the development of RePJI using conditional logistic regression, adjusted for possible confounding factors. We included 90 cases from 12 centers, which were compared with 172 controls. The most frequent causative microorganism was Staphylococcus epidermidis with 34 cases (37.8%). Staphylococci were responsible for 50 cases (55.6%), 32 of them (64%) methicillin-resistant. Gram-negative bacilli were involved in 30 cases (33.3%), the most common Pseudomonas aeruginosa. In total, 83 different antibiotic prophylaxis regimens were used in 2nd-stage surgery, the most frequent a single preoperative dose of cefazolin (48 occasions; 18.3%); however, it was most common a combination of a glycopeptide and a beta-lactam with activity against Pseudomonas spp (99 cases, 25.2%). In the adjusted analysis, regimens that included antibiotics with activity against methicillin-resistant staphylococci AND Pseudomonas spp were associated with a significantly lower risk of RePJI (adjusted OR = 0.24; 95% IC: 0.09-0.65). The lack of standardization in 2nd-satge surgery prophylaxis explains the wide diversity of regimens used in this procedure. The results suggest that antibiotic prophylaxis in this surgery should include an antibiotic with activity against methicillin-resistant staphylococci and Pseudomonas.

Characterization of linezolid- and methicillin-resistant coagulase-negative staphylococci in a tertiary hospital in China

BackgroundRecently, linezolid-resistant staphylococci have become an emerging problem worldwide. Understanding the mechanisms of resistance, molecular epidemiology and transmission of linezolid-resistant CoNS in hospitals is very important.MethodsThe antimicrobial susceptibilities of all isolates were determined by the microdilution method. The resistance mechanisms and molecular characteristics of the strains were determined using whole-genome sequencing and PCR.ResultsAll the strains were resistant to oxacillin and carried the mecA gene; 13 patients (36.1%) had prior linezolid exposure. Most S. epidermidis and S. hominis isolates were ST22 and ST1, respectively. MLST typing and evolutionary analysis indicated most linezolid-resistant CoNS strains were genetically related. In this study, we revealed that distinct CoNS strains have different mechanisms of linezolid resistance. Among ST22-type S. epidermidis, acquisition of the T2504A and C2534T mutations in the V domain of the 23 S rRNA gene, as well as mutations in the ribosomal proteins L3 (L101V, G152D, and D159Y) and L4 (N158S), were linked to the development of linezolid resistance. In S. cohnii isolates, cfr, S158Y and D159Y mutations in the ribosomal protein L3 were detected. Additionally, emergence of the G2576T mutation and the cfr gene were major causes of linezolid resistance in S. hominis isolates. The cfr gene, G2576T and C2104T mutations, M156T change in L3 protein, and I188S change in L4 protein were found in S. capitis isolates.ConclusionThe emergence of linezolid-resistant CoNS in the environment is concerning because it involves clonal dissemination and frequently coexists with various drug resistance mechanisms.

Methicillin-resistant staphylococcus aureus: Prevalence and antimicrobial efficacy in a tertiary care hospital in Saudi Arabia

Methicillin-resistant staphylococcus aureus: Prevalence and antimicrobial efficacy in a tertiary care hospital in Saudi Arabia

A 10-year Retrospective Review of Patient-to-Patient Transmitted Pathogens in Culture-Positive Burn Wounds at a Tertiary Burn Center

Introduction: Burn wound infection can progress to sepsis and is a significant source of morbidity and mortality. Prevalence of multidrug-resistant organisms are high in burn patients; these organisms can be transmitted between patients leading to poor outcomes. Objectives: To characterize patient-to-patient transmission of pathogens causing burn wound colonization at a single tertiary hospital burn center in Hamilton, Canada from 2011 to 2020. Methods: Retrospective chart review of patients admitted to the burn trauma unit at Hamilton General Hospital between 2011 and 2020. Antibiotic susceptibility panels of pathogens cultured from burn patients’ wound swab/tissue cultures were compared against pathogens cultured from other burn/nonburn patients with overlapping admission dates. Pathogens were categorized into likely, possible, or unlikely transmission, or normal skin flora on a case-by-case basis. Results: There were 173 burn patients with positive wound culture and 613 nonburn patients included in the study. Included burn patients had median age 52 years, mostly male (73%) with flame injury (65%), and median total body surface area 18%. There were 18 patients (10%) with likely transmission and 54 patients (31%) with possible transmission. Most frequently implicated pathogens for likely patient-to-patient transmission were methicillin-resistant Staphylococcus aureus (MRSA) (7 patients) and methicillin-resistant coagulase-negative Staphylococci (4 patients). Both burn and nonburn patients were implicated. Conclusion: The burden of patient-to-patient transmission in culture-positive burn wounds was estimated to be between 10% and 41%. Greater care should be taken to avoid patient-to-patient transmission of pathogens to minimize burn infection morbidity and mortality. Prospective studies should be conducted with genomic sequencing and correlation with clinical outcomes.

Antibiotic use and resistance patterns at Rumphi District Hospital in Malawi: a cross-sectional study

BackgroundOveruse of antibiotics is a key driver of antimicrobial resistance (AMR) world-wide. Malawi continues to report rising cases of AMR among both in-patients and out-patients. We investigated antibiotic use and resistance patterns among patients with suspected first line antibiotic treatment failure at Rumphi District Hospital, Malawi.MethodsWe used a cross-sectional study design in which records of patients data on culture and antimicrobial sensitivity tests were extracted, alongside treatment history from 2019 to March, 2023, retrospectively. We also included findings for point prevalence survey (PPS) conducted within four hospital wards in June, 2022 by a well-trained multi-disciplinary team from within the hospital. The data was analyzed for antibiotic use, characterization of pathogens and their susceptibility patterns using Microsoft excel and STATA-14 software.ResultsA total of 85 patients’ data records were reviewed on antibiotics resistance pattern in which 54 (63.5%) were females. Patient antibiotic history captured indicated Metronidazole (23%), Gentamycin (20%) and Doxycycline (23%) as the most frequently used antibiotics among clients referred for microbiological investigations. Among locally available antibiotics with over 50% sensitivity were Chloramphenicol (61%), ciprofloxacin (55%), and ceftriaxone (54%). Penicillins were among antibiotics with highest resistance: ampicillin (100%), amoxyclav (90%), Piperacilin-tazobactam (63%). The majority of patients came from STI clinic and presented with genital discharges 44% (n = 39). Over 80% of the isolated N. gonorrhoeae exhibited a reduced susceptibility to gentamycin. Prevalence of Methicillin resistant staphylococcus Aureus (MRSA) was 46% and were mostly isolated from wound pus. Among 80 data records of the patients reviewed during PPS, Ceftriaxone (54.3%) and Metronidazole (23.3%) emerged as the most frequently used antibiotics in the wards which were prescribed empirically without a microbiological indication.ConclusionIn this study setting, we observed high use of watch antibiotics along with problem of multi-drug resistant infections in patients experiencing clinical failure in a variety of clinical syndromes. The findings underline the need to revamp diagnostic microbiology to increase the uptake of antimicrobial susceptibility testing to guide specific prescriptions of broad-spectrum antibiotics in the watch list.

Preventive strategies to reduce the rate of periprosthetic infections in total joint arthroplasty; a comprehensive review.

The increasing frequency of total hip (THA) and knee arthroplasties (TKA) is marred by the rise in periprosthetic joint infections (PJIs) and surgical site infections (SSIs), with PJIs incurring costs over $1.62 billion as of 2020 and individual case management averaging $90,000. SSIs additionally burden the U.S. healthcare economy with billions in expenses annually. PJI prevalence in primary THA and TKA ranges from 0.5% to 2.4%, spiking to 20% in revisions and representing 25% of TKA revision causes. Projections estimate up to 270,000 annual PJI cases by 2030. Often caused by gram-positive bacteria, particularly methicillin-resistant staphylococci, these infections demand preventive measures. This review dissects PJI prevention across preoperative, intraoperative, and perioperative phases, aligning with evidence-based CDC and WHO guidelines. Preoperative measures include managing diabetes, obesity, tobacco use, Staphylococcus aureus screening and nasal decolonization, nutritional optimization, and management of inflammatory arthropathies. Intraoperatively, antibiotic prophylaxis, skin preparation, operative room environmental controls, surgical technique precision, and irrigation options are scrutinized. Perioperative concerns focus on anticoagulation, blood management, and infection risk mitigation. Integrating these strategies promotes a patient-centric care model, aiming to reduce PJI incidence, improve patient outcomes, and increase care cost-effectiveness in joint arthroplasty.

Active surveillance of antimicrobial resistance in companion animals: A pilot study in a Spanish Veterinary Teaching Hospital

The role of small animal veterinary hospitals in the onset and dissemination of antimicrobial-resistant organisms (AMROs) is still not clear, and the implementation of an internal surveillance systems is a cost-effective tool to better understand their impact. The aim of this study was to describe a pilot program of active surveillance in a Spanish Veterinary Teaching Hospital, developed to estimate the detection frequency of AMROs in the commensal flora of patients and in the environment. Surveillance was focused on Methicillin-resistant Staphylococci (MRS), third generation cephalosporins resistant gram-negative bacteria (3GCR-GNB), and carbapenems-resistant gram-negative bacteria (CR-GNB). Oral and perirectal swabs were collected in the same dogs and cats hospitalized > 48 h, at their admission and before their discharge. Out of 50 patients sampled, 24% (12/50) were carriers at admission of at least one of the three investigated AMROs. Twenty-eight percent of patients (14/50) acquired at least one AMRO during the hospital stay. MRS detection frequency at admission was 12% (6/50), while acquisition was 6% (3/50). 3GCR-GNB detection frequency was 14% at admission (7/50) and acquisition 22% (11/50), while CR-GNB detection frequency was 2% at admission (1/50) and acquisition 2% (1/50). Environmental surveillance (98 samples) showed a total detection frequency of 22.4% for MRS (22/98), 2% for 3GCR-GNB and CR-GNB (2/98). Clinical staff’ shoe soles showed high detection frequency for MRS (50%). 3GCR Escherichia coli was the most isolated species in patients (n = 17). The results show how active surveillance can be used as a tool to assess the impact of AMROs in veterinary hospitals to subsequently build up tailored control plans based on specific issues.

267 Risk Factors Associated With Baclofen Pump Infection in Children Translated Into Health-Care Costs: A Retrospective Analysis From the Children's Hospital of Pittsburgh Experience From 2009-2020

INTRODUCTION: Intrathecal baclofen infusion is often used as a therapy for spasticity in children and adults, with pediatric cases more associated with infections. Infection leads to the need for pump explantation and is associated with a significantly increased hospitalization cost. METHODS: We retrospectively reviewed demographic, clinical, and economic data for children who underwent surgery for intrathecal baclofen pumps at a single institution from 2009-2020. Bivariable analyses (chi-squared tests) were conducted to compare differences in clinical characteristics between patients with surgical site infection and those without. Mann-Whitney tests were performed to compare total charges per patient between patients who had an infection versus those who did not. RESULTS: A total of 199 patients undergoing 442 surgeries were included. The cohort was 64% male and 84% Caucasian, with a mean age of 13.3 years. The most common indication for placement was cerebral palsy. Infection occurred in 28 patients (14% infection rate). The most common organisms were methicillin-resistant and methicillin-sensitive staph aureus. The pump model, access site, and the number of surgeons scrubbed were not associated with infection. Total hospital charges (for all surgeries) were significantly higher for patients with an infection versus those who did not ($231,762 vs. $187,028, p=0.0078), with an average charge increase of $44,734 associated with surgical site infection. CONCLUSIONS: In our single-center series, the most common indication for baclofen pump placement was cerebral palsy, with an infection rate of 14%, close to other rates reported in the literature. Total hospital charges were higher for patients with an associated surgical site infection than those without one.

The fabrication process of polydimethylsiloxane (PDMS) nanostructured films with antimicrobial properties against methicillin-resistant staphylococcus aureus (MRSA)

Physical topography modification is an approach to fabricate nanostructures surfaces with antimicrobial properties. Lithography-based technologies offer an effective technique to develop the desired sizes and geometry. The replica molding technique was employed to fabricate the PDMS nanostructures using the PMMA imaging layer and characterized using a FESEM and AFM. The cell viability of gram-positive bacteria on structural diminished by almost 80% and the cells were deformed and ruptured once attached to the structured surface. Thus, the PDMS structured surface enhanced the bactericidal properties of the film, which effectively inhibit bacterial attachment.

Microbiological Quality and Safety of Fresh Rabbit Meat with Special Reference to Methicillin-Resistant S. aureus (MRSA) and ESBL-Producing E. coli.

The purpose of this investigation was to evaluate the microbial quality and safety of rabbit meat. A total of 49 rabbit meat samples were taken at the retail level. The mesophiles, staphylococci, Enterobacterales, and Pseudomonas spp. counts were 4.94 ± 1.08, 2.59 ± 0.70, 2.82 ± 0.67, and 3.23 ± 0.76 log CFU/g, respectively. Campylobacter spp. were not detected in any sample. Listeria monocytogenes was isolated from one sample (2.04%) at levels below 1.00 log CFU/g. Multi-resistant S aureus was found in seven samples (14.9%). Methicillin-resistant S. aureus, S. epidermidis, S. haemolyticus, M. caseolyticus, and M. sciuri were found in a sample each (10.20%), and all of them were multi-resistant. Multi-resistant ESBL-producing E. coli were detected in two samples from the same retailer (4.08%). The high resistance found in methicillin-resistant staphylococci and ESBL-producing E. coli is of particular concern, and suggests that special measures should be taken in rabbit meat.

Spectrum and antibiotic sensitivity of bacterial keratitis: a retrospective analysis of eight years in a Tertiary Referral Hospital in Southwest China.

The objective of this study was to investigate the epidemiological characteristics, distribution of isolates, prevailing patterns, and antibiotic susceptibility of bacterial keratitis (BK) in a Tertiary Referral Hospital located in Southwest China. A retrospective analysis was conducted on 660 cases of bacterial keratitis occurring between January 2015 and December 2022. The demographic data, predisposing factors, microbial findings, and antibiotic sensitivity profiles were examined. Corneal trauma emerged as the most prevalent predisposing factor, accounting for 37.1% of cases. Among these cases, bacterial culture results were positive in 318 cases, 68 species of bacteria were identified. The most common Gram-Positive bacteria isolated overall was the staphylococcus epidermis and the most common Gram-Negative bacteria isolated was Pseudomonas aeruginosa. Methicillin-Resistant Staphylococci accounted for 18.1% of all Gram-Positive bacteria. The detection rate of P. aeruginosa showed an increasing trend over time (Rs=0.738, P=0.037). There was a significant decrease in the percentage of Gram-Negative microorganisms over time (Rs=0.743, P=0.035). The sensitivity of Gram-Positive bacteria to linezolid, vancomycin, tigecycline, quinupristin/dalfopristin, and rifampicin was over 98%. The sensitivity rates of Gram-Negative bacteria to amikacin, meropenem, piperacillin/tazobactam, cefoperazone sodium/sulbactam, ceftazidime, and cefepime were all above 85%. In patients with a history of vegetative trauma, the possibility of BK should be taken into account in addition to the focus on fungal keratitis. The microbial composition primarily consists of Gram-Positive cocci and Gram-Negative bacilli. Among the Gram-Positive bacteria, S. epidermidis and Streptococcus pneumoniae are the most frequently encountered, while P. aeruginosa is the predominant Gram-Negative bacteria. To combat Gram-Positive bacteria, vancomycin, linezolid, and rifampicin are considered excellent antimicrobial agents. When targeting Gram-Negative pathogens, third-generation cephalosporins exhibit superior sensitivity compared to first and second-generation counterparts. As an initial empirical treatment for severe cases of bacterial keratitis and those unresponsive to fourth-generation fluoroquinolones in community settings, the combination therapy of vancomycin and tobramycin is a justifiable approach. Bacterial keratitis can be better managed by understanding the local etiology and antibacterial drug susceptibility patterns.

Ceftaroline for Central Nervous System Infections: Case Report of a Young Infant, and Scoping Review.

Managing health care acquired and device-associated intracranial infections in young children can be challenging given adverse antibiotic side effects and difficulties in achieving adequate central nervous system (CNS) antibiotic concentrations. Ceftaroline is a cephalosporin with a favorable safety profile and activity against methicillin-resistant Staphylococci and several Gram-negative organisms. Published data on the use of ceftaroline for CNS infections in children and adults are limited. We describe a 2-month-old infant with ventriculo-subgaleal shunt-associated methicillin-resistant Staphylococcus epidermidis ventriculitis, which was successfully treated with ceftaroline, in addition to vancomycin and rifampin. We conducted a scoping review of English-language literature retrieved from PubMed, EMBASE and Web of Science that assessed the use of ceftaroline for CNS infections. We identified 22 articles for inclusion in our review, which described 92 unique patients, of whom 2 were <21 years old. Ceftaroline was commonly used in conjunction with other antibiotics to treat infections caused by Staphylococcus aureus, coagulase-negative Staphylococci and Streptococcus pneumoniae. Most case reports described clinical success with ceftaroline, though small case series and cohort studies yielded mixed efficacy assessments. Adverse effects attributed to ceftaroline were rare and included reversible myelosuppression, eosinophilia, hepatotoxicity and nephrotoxicity. Pharmacokinetic/pharmacodynamic studies suggested similar CNS penetration through inflamed meninges as other beta lactam antibiotics. We identified a growing body of published evidence supporting the use of ceftaroline in combination with other agents for the treatment of CNS infections. In absence of clinical trials, additional real-world data are needed to define the efficacy and safety of ceftaroline for children and adults with CNS infections.

Microorganism diversity and contamination risk in mosque rosaries and carpets.

Inevitably, the floors of mosques are contaminated with microorganisms, and the risk of pathogen transmission is probably high between the many visitors, but the issue has been infrequently studied. Investigate microorganism variety and risk of contamination on commonly used carpets and rosaries (prayer beads). Cross-sectional. Mosques. This study was carried out in three different cities of Turkey in 2023, focusing on mosques located around hospitals. Forty mosques were included in the study and from each mosque 10 samples were collected from various parts of carpets and rosaries. The number of positive culture isolates were identified. Diversity and distribution of microorganisms isolated from mosque carpets and rosaries; methicillin-resistance rates in Staphylococci. 400 samples. Growth was observed in 368 (92%) of 400 samples examined. The microorganisms isolated in the highest number were methicillin-susceptible coagulase negative Staphylococci (MSCoNS) (59.8%), Microcooccus (41%) and diphtheroids (31.3%). The rates of total growth (P=.001), including diphtheroids (P=.018), methicillin-resistant coagulase negative Staphylococci (P=.001), Bacillus spp. (P=.036) and Aspergillus spp. (P=.002) rates were significantly higher in the rosary samples than carpet samples. At mosques in Tokat, a province center, 4 samples were positive for Acinetobacter baumannii, two samples were positive for Pseudomonas aeruginosa and one sample for methicillin-resistant Staphylococcus aureus (MRSA), and these were isolated from rosaries. 0.3% of Staphylococcus isolates were MRSA. As there is a high risk of contamination of carpets and prayer beads on the mosque floor with human flora, the use of appropriate hygiene practices is necessary. We also found some emerging bacteria in addition to the normal human flora. Our study was conducted in three provinces. Further studies might cover a wider geography.

Risk factors for resistant gram-positive bacteremia in febrile neutropenic patients with cancer

BackgroundGram-positive bacteria are frequently resistant to empirical beta‐lactams in febrile neutropenic patients with cancer. As microbiology and antibiotic susceptibility changes, we reevaluated the risk factors for resistant Gram-positive bacteremia in febrile neutropenic patients with cancer. MethodsEpisodes of bacteremic febrile neutropenia in Seoul National University Hospital from July 2019 to June 2022 were reviewed. Resistant Gram-positive bacteria were defined as a pathogen susceptible only to glycopeptide or linezolid in vitro (e.g., methicillin-resistant staphylococci, penicillin-resistant viridans streptococci, and ampicillin-resistant enterococci). Episodes were compared to identify independent risk factors for resistant Gram-positive bacteremia. ResultsOf 225 episodes, 78 (34.7%) involved resistant Gram-positive bacteremia. Multivariate analysis revealed that breakthrough bacteremia while being administered antibiotics (adjusted odds ratio [aOR], 6.794; 95% confidence interval [95% CI], 3.130–14.749; P < 0.001) and catheter-related infection (aOR 4.039, 95% CI 1.366–11.946; P = 0.012) were associated with resistant Gram-positive bacteremia. Chronic liver disease (aOR 0.231, 95% CI 0.059–0.905; P = 0.035) and hypotension at bacteremia (aOR 0.454, 95% CI 0.218–0.945; P = 0.035) were inversely associated with resistant Gram-positive bacteremia. ConclusionsResistant Gram-positive bacteria should be considered in breakthrough bacteremia and catheter-related infection in febrile neutropenic patients with cancer.

Evaluation of two commercial broth microdilution systems for dalbavancin susceptibility testing of methicillin-resistant Staphylococcus aureus and other resistant Gram-positive cocci

ObjectivesThis study aims to evaluate two commercial broth microdilution (BMD) systems, E1-185-100 (Merlin) and FDANDPF (ThermoFisher), for dalbavancin susceptibility testing in comparison with reference BMD assay. MethodsStudy collection was composed of 200 non-replicate multidrug-resistant Gram-positive cocci of clinical origin, including 180 methicillin-resistant Staphylococcus aureus, 10 vancomycin-resistant enterococci, seven linezolid-resistant Staphylococcus epidermidis, and three methicillin-resistant coagulase-negative staphylococci. S. aureus ATCC 29213 and Enterococcus faecalis ATCC 29212 reference strains were also included as controls. Testing was performed according to the ISO 20776-1 standard, starting from the same bacterial inoculum, and results were compared according to the ISO 20776-2 standard. ResultsReference BMD showed that 92.6% (187/202) of the strains were susceptible to dalbavancin, whereas few staphylococci and all VanA-producing enterococci showed a resistant phenotype. In comparison with the reference method, Category Agreement and Essential Agreement were 98% (198/202; 95% CI, 95.4–99.3%) and 98% (198/202; 95% CI, 95.4–99.3%) for both Merlin and ThermoFisher panels. A few false susceptibilities were observed, for both commercial systems, with dalbavancin-resistant staphylococci. BIAS values of 11% and 3% were calculated for the Merlin and ThermoFisher systems, respectively. DiscussionThis study, reporting the first evaluation of the two commercially available BMD assays for dalbavancin susceptibility testing, revealed an overall good correlation with reference BMD, although with some underestimation tendency of MIC values by both commercial systems. Further studies involving a higher number of resistant isolates will be necessary to better evaluate this issue.

Microbiology and drug sensitivity of Surgical Site Infections in Pakistan: A Systematic Review

Abstract Various bacterial pathogens that are known to cause Surgical Site Infections (SSI) are becoming increasingly resistant to many antibiotics. The aim of this systematic review was to see various pathogens responsible to cause SSI in Pakistan and to see their drug sensitivity patterns according to culture and sensitivity reports during last five years. This systematic review was conducted according to the preferred reporting items for systematic reviews and met analysis (PRISMA) guidelines. Extensive search of medical databases Pubmed, Google Scholar and Pakmedinet was done. Four studies were selected from various cities of Pakistan. Most common bacterial pathogen isolated was staph aureus 49%, followed by Ecoli 18%, Enterococcus 8%, and Pseudomonas 7.4%. Methicillin resistant staph aureus (MRSA) was isolated as 5% and 18 % in two studies. Drug sensitivity pattern showed Vancomycin, Imipenem, Meropenem, Linezolid, Cefoperazone + Sulbactam to be the most sensitive drugs against all type of pathogens. Drugs found effective against staph aureus were Vancomycin, Linezolid, Meropenem and Fusidic acid. Drugs found sensitive against E coli were Cefoperazone Sulbactam combination, Linezolid and Meropenem. Ampicillin and Amoxicillin were found highly resistant against all pathogens. We concluded from our systematic review that most common bacterial pathogen responsible to cause SSI in Pakistan is staph aureus. Empirically Linezolid is found effective against all pathogens. Imipenem, Meropenem, sulbactam plus Cefoperazone combination, vancomycin, tazocin are effective drugs. Ampicillin, amoxicillin and ciprofloxacin are highly resistant in Pakistan. Key words: Surgical Site Infections (SSI), Staph aureus, E Coli, Culture and Sensitivity

Detection of mecA Genes in Hospital-Acquired MRSA and SOSA Strains Associated with Biofilm Formation.

Methicillin-resistant (MR) Staphylococcus aureus (SA) and others, except for Staphylococcus aureus (SOSA), are common in healthcare-associated infections. SOSA encompass largely coagulase-negative staphylococci, including coagulase-positive staphylococcal species. Biofilm formation is encoded by the icaADBC operon and is involved in virulence. mecA encodes an additional penicillin-binding protein (PBP), PBP2a, that avoids the arrival of β-lactams at the target, found in the staphylococcal cassette chromosome mec (SCCmec). This work aims to detect mecA, the bap gene, the icaADBC operon, and types of SCCmec associated to biofilm in MRSA and SOSA strains. A total of 46% (37/80) of the strains were S. aureus, 44% (35/80) S. epidermidis, 5% (4/80) S. haemolyticus, 2.5% (2/80) S. hominis, 1.25% (1/80) S. intermedius, and 1.25% (1/80) S. saprophyticus. A total of 85% were MR, of which 95.5% showed mecA and 86.7% β-lactamase producers; thus, Staphylococcus may have more than one resistance mechanism. Healthcare-associated infection strains codified type I-III genes of SCCmec; types IV and V were associated to community-acquired strains (CA). Type II prevailed in MRSA mecA strains and type II and III in MRSOSA (methicillin-resistant staphylococci other than Staphylococcus aureus). The operon icaADBC was found in 24% of SA and 14% of SOSA; probably the arrangement of the operon, fork formation, and mutations influenced the variation. Methicillin resistance was mainly mediated by the mecA gene; however, there may be other mechanisms that also participate, since biofilm production is related to genes of the icaADBC operon and methicillin resistance was not associated with biofilm production. Therefore, it is necessary to strengthen surveillance to prevent the spread of these outbreaks both in the nosocomial environment and in the community.

Exploring the anticancer and antibacterial potential of naphthoquinone derivatives: a comprehensive computational investigation.

This study investigates the potential of 2-(4-butylbenzyl)-3-hydroxynaphthalene-1,4-dione (11) and its 12 derivatives as anticancer and biofilm formation inhibitors for methicillin-resistant staphylococcus aureus using in silico methods. The study employed various computational methods, including molecular dynamics simulation molecular docking, density functional theory, and global chemical descriptors, to evaluate the interactions between the compounds and the target proteins. The docking results revealed that compounds 9, 11, 13, and ofloxacin exhibited binding affinities of -7.6, -7.9, -7.5, and -7.8kcalmol-1, respectively, against peptide methionine sulfoxide reductase msrA/msrB (PDB: 3E0M). Ligand (11) showed better inhibition for methicillin-resistant staphylococcus aureus msrA/msrB enzyme. The complex of the 3E0M-ligand 11 remained highly stable across all tested temperatures (300, 305, 310, and 320K). Principal Component Analysis (PCA) was employed to evaluate the behavior of the complex at various temperatures (300, 305, 310, and 320K), demonstrating a total variance of 85%. Convergence was confirmed by the eigenvector's cosine content value of 0.43, consistently displaying low RMSD values, with the minimum observed at 310K. Furthermore, ligand 11 emerges as the most promising candidate among the compounds examined, showcasing notable potential when considering a combination of in vitro, in vivo, and now in silico data. While the naphthoquinone derivative (11) remains the primary candidate based on comprehensive in silico studies, further analysis using Frontier molecular orbital (FMO) suggests while the Egap value of compound 11 (2.980eV) and compound 13 (2.975eV) is lower than ofloxacin (4.369eV), indicating their potential, so it can be a statement that compound 13 can also be investigated in further research.

New Frontier on Antimicrobial Therapy: Long-Acting Lipoglycopeptides.

Long-acting lipoglycopeptides (LGPs), such as dalbavancin and oritavancin, are semisynthetic antibiotics known for their strong effectiveness against a wide array of Gram-positive bacteria. This includes Staphylococcus aureus, both methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) strains, coagulase-negative Staphylococci (CoNS), streptococci, and vancomycin-sensitive Enterococcus faecalis. A literature search was conducted on PubMed and on ClinicalTrials.gov to identify articles published until July 2023 investigating the use of oritavancin and dalbavancin in clinical practice. The review included case reports, case series, observational studies, and clinical studies. Although more consistent data are needed, LGPs seem to be a good alternative that may provide a quicker hospital discharge and reduce long-term intravenous access and therapy. This is attributed to their unique pharmacologic and pharmacokinetic characteristics. More quality data (i.e., number of patients treated with clinical success) are needed before clinicians may use these therapies more widely.

Studying Microbial Ecology of Diabetic Foot Infections: Significance of PCR Analysis for Prudent Antimicrobial Stewardship.

This study presents a comprehensive investigation into the microbial ecology of diabetic foot infections (DFIs), using molecular-polymerase chain reaction (PCR) analysis to accurately identify the causative agents. One hundred DFI patients were recruited and classified using the Depth Extent Phase and Associated Etiology (DEPA) score according to their severity. Results revealed polymicrobial infections in 75% of cases, predominantly featuring Staphylococcus epidermidis (83%) and Staphylococcus aureus (63%). Importantly, 20% of samples exhibited facultative anaerobes Bacteroides fragilis or Clostridium perfringens, exclusively in high DEPA score ulcers. Candida albicans coinfection was identified in 19.2% of cases, underscoring the need for mycological evaluation. Empirical antimicrobial therapy regimens were tailored to DEPA severity, yet our findings highlighted a potential gap in methicillin-resistant Staphylococcus aureus (MRSA) coverage. Despite an 88% prevalence of methicillin-resistant Staphylococci, vancomycin usage was suboptimal. This raises concerns about the underestimation of MRSA risk and the need for tailored antibiotic guidelines. Our study demonstrates the efficacy of molecular-PCR analysis in identifying diverse microbial communities in DFIs, influencing targeted antibiotic choices. The results advocate for refined antimicrobial guidelines, considering regional variations in microbial patterns and judiciously addressing multidrug-resistant strains. This research contributes crucial insights for optimizing DFIs management and helps the physicians to have a fast decision in selection the suitable antibiotic for each patient and to decrease the risk of bacterial resistance from the improper use of broad-spectrum empirical therapies.