MRSA Rate Research Articles

Tetracycline susceptibility in multidrug resistant Staphylococcus aureus isolated from clinical samples in tertiary care hospitals of Kathmandu, Nepal.

Staphylococcus aureus, being an opportunistic pathogen, is frequently associated with various infections in human. The clinical sector feels challenge regarding the management of multidrug resistant S. aureus. Besides the B-lactam antibiotics, Glycopeptides, Tetracycline, Quinolones, Macrolide-lincosamide streptogramin B family of antibiotics are also commonly prescribed to deal with such infections as an alternative drug. Therefore, this study was conducted to assess tetracycline susceptibility in multidrug resistant S. aureus in clinical samples. This study was conducted over the period of 15 months from March 2020–May 2021. The clinical samples were collected from the three different tertiary care hospitals of Kathmandu, Dirghayu Guru Hospital, Chabahil, Bhaktapur Cancer Hospital, Bhaktapur, and Shankarapur Hospital, Jorpati. The sample processing and laboratory work was carried out in the Microbiology Laboratory of Dirghyau Guru Hospital to determine the proportion of different phenotypes of MDR among S. aureus and their association with methicillin resistance. Two hundred sixty six isolates of S. aureus were included in the study. Methicillin resistance was detected by cefoxitin disc diffusion method. Among 2004 clinical samples processed, 266 (13.27%) isolates were S. aureus. The multidrug resistant strain isolated from OPD was 56.84% (54/95) and from inpatient was 43.15% (41/95). Among the 266 S. aureus, 28.94% MRSA and 71.05% MSSA isolates were detected. Tetracycline resistance was found in 9.8% of total S. aureus isolates whereas 27.36% (26/95) among MDR S. aureus isolates. Resistance to Tetracycline was higher in MRSA as compared to MSSA. Detection rate of MRSA in this study shows the necessity to improve health care practices to control MRSA infections. Tetracycline can be used as an alternative antibiotic against the S. aureus infection.

The features of multidrug-resistant organisms between 2016 and March 2023 and its change after the end of zero-COVID-19 policy in a teaching hospital in Shenzhen, China

To investigate the clinical distribution and changing trend of antibiotic resistance profiles of multidrug-resistant organisms (MDROs), a retrospective study was undertaken. The characteristics of MDROs isolated from 2016 to March 2023 were retrospectively analysed. The detection rate of these MDROs was compared prior to COVID-19 (Period 1, 2016-2019), during the COVID-19 pandemic with restrictions (Period 2, 2020-2022), and after the end of zero-policy (Period 3, Jan-March, 2023). Antibiotic-resistant genes were detected. The overall detection rates of CRPA, CRAB, CREC, CRKP, MRSA, and VREfm were 22.6%, 22.6%, 1.3%, 4.0%, 19.5%, and 3.1%, respectively. The detection rate of CRAB was significantly lower in Period 2 and 3 compared with Period 1 (P < 0.0001). The detection rate of CRPA and VREfm was significantly increased in Period 3 compared with Period 1 and 2 (P < 0.0001). The resistance rate to ticarcillin/clavulanic acid (TIM) and piperacillin/tazobactam (TZP) has gradually increased in CRPA since 2018. NDM and KPC were the most common carbapenemase genes identified in CREC (60.0%) and CRKP isolates (47.8%), respectively. All the 10 VREfm isolates carried the vanA gene. The detection rate of CRAB has decreased since 2018, but a significantly increased prevalence of CRPA and VREfm was seen after the end of zero-policy. An increasing resistance rate to TIM and TZP was seen in CRPA. NDM, KPC, and vanA were the common genes harboured by CREC, CRKP, and VREfm, respectively. Ongoing surveillance after the COVID-19 era is suggested.

Is tropical pus in the hand special? A retrospective study comparing hand infection cases in Darwin and Adelaide.

Hand infections are a common reason for presenting to hospital and can be associated with significant morbidity and prolonged antibiotic use. Factors recognized to influence patient outcomes include resistant organisms and delayed presentation. Surgeons working around Australia may assume that hand infections and appropriate treatment algorithms will be similar between sites. This is the first study to examine differences between hand infections presenting in Darwin (with its tropical climate) vs. those in a more temperate city (Adelaide). This is a two-site retrospective study, where diagnostic discharge codes were used to identify cases for a 12-month period and patient age, sex and rurality, duration of hospital stay, microbiology results and subsequent trips to theatre were reviewed. Despite significant differences in rurality between FMC and RDH patients, there was no significant difference in length of hospital stay, duration of intravenous antibiotics or return trips to theatre across the two sites. RDH reported a 25% rate of MRSA, compared to 18% at FMC, as well as a statistically significant increase in uncommon microbes, with 30% compared to 12% of patients growing microbes that may not be covered by antibiotics routinely administered in metropolitan areas. A limitation of this study was that compliance with antibiotics and hospital stay were not accounted for. It is often our training years that determine our norms of everyday practice, but fewer Australian surgical training posts are located in tropical centres. The results of this study highlight the importance of not assuming that the spectrum of organisms causing hand infections are the same as that in the surgeons' state of origin.

Progress in the Prevalence, Classification and Drug Resistance Mechanisms of Methicillin-Resistant Staphylococcus aureus.

Staphylococcus aureus is a common human pathogen with a variety of virulence factors, which can cause multiple infectious diseases. In recent decades, due to the constant evolution and the abuse of antibiotics, Staphylococcus aureus was becoming more resistant, the infection rate of MRSA remained high, and clinical treatment of MRSA became more difficult. The genetic diversity of MRSA was mainly represented by the continuous emergence of epidemic strains, resulting in the constant changes of epidemic clones. Different classes of MRSA resulted in different epidemics and resistance characteristics, which could affect the clinical symptoms and treatments. MRSA had also spread from traditional hospitals to community and livestock environments, and the new clones established a relationship between animals and humans, promoting further evolution of MRSA. Since the resistance mechanism of MRSA is very complex, it is important to clarify these resistance mechanisms at the molecular level for the treatment of infectious diseases. We firstly described the diversity of SCCmec elements, and discussed the types of SCCmec, its drug resistance mechanisms and expression regulations. Then, we described how the vanA operon makes Staphylococcus aureus resistant to vancomycin and its expression regulation. Finally, a brief introduction was given to the drug resistance mechanisms of biofilms and efflux pump systems. Analyzing the resistance mechanism of MRSA can help study new anti-infective drugs and alleviate the evolution of MRSA. At the end of the review, we summarized the treatment strategies for MRSA infection, including antibiotics, anti-biofilm agents and effluxpump inhibitors. To sum up, here we reviewed the epidemic characteristics of Staphylococcus aureus, summarized its classifications, drug resistance mechanisms of MRSA (SCCmec element, vanA operon, biofilm and active efflux pump system) and novel therapy strategies, so as to provide a theoretical basis for the treatment of MRSA infection.

Safety of Prepping the External Fixator In Situ During Staged Internal Fixation of Pilon Fractures: A Retrospective Comparative Cohort Study.

(1) To assess the rate of fracture-related infection (FRI) and unplanned reoperation of disinfecting and prepping in the external fixator (Ex-Fix) instrument during definitive open reduction and internal fixation (ORIF) of pilon fractures treated by a staged protocol and (2) to determine whether the amount of time from external fixation to ORIF influences the risk of FRI. Retrospective cohort study. Level 1 academic trauma center. One hundred thirty-three patients who underwent operative treatment for pilon fracture between 2010 and 2020. External fixation and ORIF with or without the Ex-Fix prepped in situ during definitive fixation. FRI and unplanned reoperation rates. 133 patients were enrolled, of which 47 (35.3%) had Ex-Fix elements prepped in situ. There was an overall infection rate of 23.3% and unplanned reoperation rate of 11.3%, and there was no significant difference in rates between the 2 cohorts. Patients with Ex-Fix elements prepped in situ who developed an FRI had a higher rate of MRSA and MSSA . Diabetes ( P = 0.0019), open fracture ( P = 0.0014), and longer (≥30 days) interval to ORIF ( P = 0.0001) were associated with postoperative FRI. Prepping elements of the Ex-Fix in situ did not lead to an increase in rates of FRI or unplanned reoperation. Although diabetes and open fracture were associated with FRI risk, a stronger association was a longer interval of Ex-Fix utilization before definitive internal fixation, specifically 30 days or greater. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Estimated mortality with early empirical antibiotic coverage of methicillin-resistant Staphylococcus aureus in hospitalized patients with bacterial infections: a systematic review and meta-analysis.

We performed a systematic review and meta-analysis to estimate the effect of early active empirical antibiotics for MRSA on mortality, both in patients admitted with MRSA infections and in patients admitted with common infectious syndromes, for whom the causative pathogen may not have been MRSA. A systematic literature search was conducted using Embase, MEDLINE, PubMed, Web of Science, Cochrane, Scopus and Google Scholar from the earliest entry through to 26 April 2022. We included studies of patients hospitalized with culture-proven MRSA infections that compared mortality rates depending on whether patients received active empirical antibiotics. The primary outcome was the adjusted OR for mortality with early active empirical antibiotics. After performing random-effects meta-analysis, we estimated the absolute risk reduction in mortality with initial empirical MRSA coverage for common infectious syndromes based on the prevalence of MRSA and baseline mortality rate for each syndrome, as reported in the medical literature. Of an initial 2136 unique manuscripts, 37 studies (11 661 participants) met our inclusion criteria. Fifteen studies (6066 participants) reported adjusted OR of mortality. The pooled adjusted OR for mortality was 0.64 (95% CI, 0.48-0.84), favouring active empirical antibiotics. The estimated absolute mortality benefit was 0% for patients with pneumonia, 0.1% (95% CI, 0.04-0.2) for non-critically ill patients with soft tissue infections, 0.04% (95% CI, 0.01-0.05) for non-critically ill patients with urinary tract infections, 0.6% (95% CI, 0.2-1.0) for patients with septic shock, and 1.0% (95% CI, 0.3-1.4) for patients with catheter-related infections admitted to ICUs. For the three most common infections in the hospital, the absolute benefit on mortality of empirical antibiotics against MRSA is 0.1% or less. Meaningful benefit of empirical antimicrobials against MRSA is limited to patients with approximately 30% mortality and 10% prevalence of MRSA. Avoiding empirical antibiotics against MRSA for low-risk infections would substantially reduce the use of anti-MRSA therapy.

Prevalence and Antimicrobial Susceptibility Pattern of Methicillin Resistant Staphylococcus aureus From Healthcare And Community Associated Sources

Introduction: Staphylococci are Gram-positive bacteria with diameter of 1 μm. Staphylococcus aureus is a versatile human pathogen responsible for nosocomial and community-associated infections which is associated with high morbidity and mortality. MRSA (also known as Mercer) is a bacterium responsible for several infections in humans that are difficult to treat. The study aimed at screening of microbial flora on mobile phones to find out the prevalence and antimicrobial susceptibility pattern of methicillin resistant Staphylococcus aureus. Materials and Methods: The present study was carried out in the Department of Medical Microbiology, NIMS Medical College and Hospital, NIMS University, Jaipur during the period of January 2014-June 2014. Results: The present study showed males prevalence of MRSA than Females. MRSA was seen among the age group 21-40 years. Maximum MRSA were obtained from pus/wound samples 12 (66.6%). The present study showed higher prevalence rate of MRSA from Doctors mobile phones. Higher prevalence rate of MRSA 58.8% in Hospital associated as compared to community associated sources 40%. HA(MRSA) showed highest resistance to penicillin 100%. The present study showed 35% MDR MRSA in HA. CA(MRSA) showed higher resistance to penicillin and ciprofloxacin 100%. HA and CAMRSA showed vancomycin and Linezolid 0% resistance. Conclusion: The study showed a higher prevalence of MRSA in HA as compared to CA sources and indicated high risk of infection in individual exposed to hospital environment. Thus, there is a need to screen individuals in hospitals for risk exposure and infection, to avoid outbreak and cross infection. There is a need of taking good Infection control measures and suggested that microbiological surveillance and monitoring of susceptibility patterns of MRSA may also help in arresting the spread of infections.

Molecular Characterization of MRSA Isolated from Camels and their Surrounding Environment

To investigate the effect of the environment in MRSA transmission to camels, this study was performed in North Coast area and Al America District (Mariot Station), Egypt on camels (Camelus dromedarius), comprising 30 females and 10 males aged between one and five years old. A total of 100 various samples including nasal swabs (40), milk (30), soil (15) and water (15) were collected from 40 camels to isolate methicillin-resistant Staphylococcus aureus using oxacillin resistance screening agar basal medium (ORSAB) beside determination of antibiogram pattern of the recovered isolates and molecular detection of some genes responsible for antibiotic resistance. It was found that the recovery rate of MRSA was 12.5, 6.67, 13.3 and 6.67% from the examined samples, respectively. Multidrug resistance was displayed by all MRSA isolates with 100% resistance to Cefoxitin and penicillin and with 80% resistance to Gentamycin, while 90% of the isolates were susceptible to Doxycycline, Linezolid and Ofloxacin and 70% to Sulfamethoxazole/Trimethoprim. Finally, MRSA strains were discovered in camels and the surrounding area, suggesting that they may contribute to the spread of the pathogen among animals and people as well as within the community. Disinfecting soil and water using a selective, effective disinfectant may be a solution to this issue.

1864. Trends in Staphylococcus aureus Bacteremia Rates among U.S. Acute Care Hospitals, January 2017- June 2021

Abstract Background Previous estimates of methicillin-resistant and -sensitive Staphylococcus aureus (MRSA, MSSA) bacteremia rates in hospitalized patients showed decreases in hospital-onset (HO) MRSA, no changes in community-onset (CO) MRSA and HO MSSA, and slight increases in CO MSSA rates from 2012–2017; more recent trends have not been well characterized. Methods We calculated monthly S. aureus bacteremia rates using microbiology data from hospitals reporting antibiotic susceptibility results in the Premier Healthcare Database from January 2017- June 2021. S. aureus blood isolates resistant to methicillin, oxacillin, or cefoxitin were categorized as MRSA. Positive blood cultures collected on or before hospital day 3 were categorized as CO; those collected on day 4 or later were categorized as HO. Annual rate differences were assessed using generalized estimating equation models with a negative binomial distribution adjusting for hospital bed size, teaching status, urban/rural designation, discharge month, census division, distributions of patient age, sex and race and hospital-level clustering. Results Among 11 million discharges from 356 hospitals, we identified 5,627 HO S. aureus bacteremia events: 2,558 (45%) MRSA and 3,069 (55%) MSSA. In 2017, we observed HO MRSA bacteremia rates of 0.41 and HO MSSA rates of 0.49 per 10,000 patient-days. Compared with 2017, adjusted rates of HO MRSA and MSSA bacteremia were significantly higher in 2019, 2020, and 2021 (Figure 1). Of 42,587 CO S. aureus bacteremia events, 19,107 (45%) were MRSA and 23,480 (55%) MSSA. CO MRSA bacteremia rates were lowest in 2017 (1.52 per 1,000 discharges), and adjusted rates were significantly higher in all later years (Figure 2); we observed significant regional variability in annual differences (p=0.018). The observed CO MSSA bacteremia rate was 2.03 per 1,000 discharges in 2017, and adjusted rates were significantly higher in 2020 and 2021. Figure 1.Hospital-Onset MRSA and MSSA Bacteremia Incidence Rate Ratios* with 95% confidence intervals, 2017 – 2021**.*Reference year =2017.**2021 includes data during January – June.***Statistically significant at p&amp;lt;0.05.Figure 2.Community-Onset MRSA and MSSA Bacteremia Incidence Rate Ratios* with 95% confidence intervals, 2017 - 2021***Reference year =2017.**2021 includes data during January – June.***Statistically significant at p&amp;lt;0.05. Conclusion In contrast with previous trends, recent S. aureus bacteremia rates in this cohort have increased in comparison to 2017. Potential explanations warranting exploration include differences in regional trends and pandemic-associated changes in inpatient risk, severity of illness, length of stay, and hospital utilization Disclosures All Authors: No reported disclosures.

BACTERIAL INFECTION MODEL AND ANTIBIOTIC RESISTANCE AT THE NEW PRIVATE HOSPITAL

Objectives: Survey of bacterial pathogens and antibiotic resistance at Tam Anh Hospital in 2021.Material and methods: Retrospective method. Bacteria were isolated from specimens at the Department Microbiology of Laboratory center at Tam Anh Hospital in 2021 which were identified and tested drug susceptibility by Vitek 2. By CLSI standards.Results: Distribution of pathogenic strains: In 2021, 880 strains of bacteria were isolated, 8 types of most common bacteria were Escherichia coli (46%), Staphylococcus aureus (16.8%), Klebsiella pneumoniae (14.3%), Staphylococcus haemolyticus (6%), Pseudomonas aeruginosa (4.3%), Enterococcus faecalis (3.9%), Enterobacter cloacae (2.9%), Acinetobacter baumannii (2.3%). Antibiotic resistance: Escherichia coli was resistant to most second and third generation cephalosporins, trimethoprim/sulfamethoxazole, fluoroquinolone, still sensitive to carbapenems, piperacillin/tazobactam, amikacin, tigecylin, cefepime, ceftazidim, gentamycin, tobramycin, nutrofurantoin. The ESBL rate was 36%. Staphylococcus aureus was resistant &gt; 30% to bezilpenicillin, erythromycin, clindamycin, oxacillin, tetracycline, still sensitive to levofloxacin; rifamycin, Vancomycin; fusidic acid; nitrofurantoin; linezolid; teicoplanin; tigecycline. The MRSA rate is 59.6%. Klebsiella pneumoniae was resistant &gt; 30% to cephalosporin, fluoroquinolone, ampicillin/sulbactam, piperacillin/tazobactam, nitrofurantoin,moxifloxacin. For meropenem were resistant 18%, ertapenem 19%. The ESBL rate was 19%. Staphylococcus heamolyticus was resistant &gt; 30% to fluoroquinolone, bezilpenicillin, erythromycin, fusidic acid, oxacillin, trimethoprim/sulfamethoxazole. Tetracycline, still sensitive to moxifloxacin, rifamycin, nitrofurantoin, gentamicin, linezolid, teicoplanin, tigecycline, vancomycin.Pseudomonas aeruginosa was resistance &gt; 30% to cephalosporin, aminoglycoside, fluoroquinolone, tigecylin, cefepime, was resistance &gt; 20% to meropenem, ceftazidime, imipenem, piperacillin/tazobactam, especially not resistance to colistin. acinetobacter baumannii was resistance &gt; 50% to cephalosporin, aminoglycoside, carbapenem, piperacillin/tazobactam, ticarcillin/clavuclanic acid, trimethoprim/sulfamethoxazole still sensitive to colistin, tigecycline; tobramycin.Conclusion: The common bacteria in at Tam Anh Ho Chi Minh Hospital in 2021 were Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Staphylococcus haemolyticus, Pseudomonas aeruginosa, Enterococcus faecalis, Enterobacter cloacae, Acinetobacter baumannii. In the current situation of multidrug resistant bacteria, understanding the distribution of sepsis parthogens and updating their antibiotic resistance will be a great help to clinicians in the antibiotic selection to treat as well as contribute to reduce antibiotic resistance,

1223. The Impact of the COVID-19 Pandemic on the Prevalence of Multidrug-resistant Organisms in Veterans Affairs Nursing Homes

Abstract Background Multidrug-resistant organisms (MDRO) in long-term care facilities are prevalent and pose a major health concern for their residents. During the COVID-19 pandemic, infection control measures were justifiably heightened in every aspect of health care, including nursing homes. There are reports depicting decreasing prevalence of MDRO in hospital settings during the pandemic. We compared the prevalence of MDRO in our facility’s nursing homes in the two-year period before vs. the two years of the pandemic. Methods Northport Veterans Affairs Medical Center provides long-term nursing home care structured as community living centers including mental health and hospice care; a 139 total bed capacity. A retrospective review of culture data collected by infection control preventionists comparing the prevalence of MDROs between 1 March 2018 to 28 February 2022 was performed. Data included: Nasopharyngeal MRSA swabs, urine, wound, blood, sputum cultures, C. difficile toxin and PCR assays. MDRO included ESBL E. coli, K. pneumoniae, P. mirabilis, MDR Pseudomonas spp (resistance to 2/3 antibiotics: cefepime/piperacillin-tazobactam/ciprofloxacin), carbapenem-resistant Pseudomonas spp, and vancomycin-resistant Enterococcus spp. Results There were 75209 bed days of care from 1 March 2018 to 28 February 2020 vs. 77531 from 1 March 2020 to 28 February 2022. The MRSA rate per 1000 patient days decreased from 4.98 pre-COVID to 2.70 during-COVID, P &amp;lt; 0.001. Similarly, there was a decrease in C. difficile 0.69 vs. 0.13, P&amp;lt; 0.001, ESBL E. coli 0.53 vs. 0.51, P&amp;lt; 0.001 and S. maltophilia (no cases during COVID). There was an increase in ESBL K. pneumoniae 0.51 vs. 0.63, P&amp;lt; 0.001, MDR Pseudomonas 0.05 vs. 0.49, P&amp;lt; 0.001, carbapenem-resistant Pseudomonas 0.026 vs. 0.077, P&amp;lt; 0.001 and VRE 0.22 vs. 0.31, P&amp;lt; 0.001. There were no Candida auris or Acinetobacter spp detected in the study period. MDRO occurrences before and during COVID-19 pandemic Conclusion While increased awareness and implementation of infection control measures during the years of the COVID-19 pandemic led to decrease in certain infections in our nursing homes, like C. difficile, a surprising uptick in ESBL K. pneumoniae and MDR Pseudomonas was noted. This is a concerning trend that merits further study to identify molecular factors and increase stewardship efforts in diligent use of carbapenems. Disclosures All Authors: No reported disclosures.

IN VITRO ACTIVITY OF MUPIROCIN ON STAPHYLOCOCCAL NASAL CARRIERS AMONG HEALTH CARE PERSONNEL IN A TERTIARY CARE HOSPITAL, JAIPUR, INDIA.

Introduction: Mupirocin (pseudomonic acid A) is an antibacterial agent with topical usage and wonderful antistaphylococcal and antistreptococcal characteristics. The formulation for nasal usage has been permitted by the U.S. Food and Drug Administration to eradicate nasal infections in adults. Healthcare workers possessing S. aureus as healthy carriers can be major origin of infection for the admitted patients. The anterior nares have proved to be the major reservoir for strains of S. aureus in both adult and children masses. To determine the Objective: prevalence of mupirocin susceptibility in S. aureus, coagulase-negative staphylococci (CoNS) and MRSA species by disk diffusion. A total of 100 nasal swabs were collected from health care personnel, aseptically during Materials And Methods: the study period. All the swab samples were processed immediately and isolated by standard microbiological methods. Antibiotic susceptibility testing was done by Kirby-Bauer disc diffusion method. Carriage rat Results: e of staphylococci was found to be 51% (including 44% of S. aureus and 7% CoNS), out of 100 nasal swabs collected during the study period. Prevalence rate of MRSA is detected to be 60.7% (31/44) in the health care workers. A total of 13 MSSA were detected in the sample collected from the anterior nares and 5 cases of MRCoNS also observed. The present study shows that all the identied S. aureus isolates were susceptible to low level mupirocin (5µg) as well as high level mupirocin (200µg). Nasal carri Conclusions: age of S. aureus is a major threat for public health as they can disseminate the same to the patients as well as to their colleagues. To reduce the prevalence and antimicrobial resistance, emphasis should be given to aseptic precaution, protective measures and topical application of mupirocin for eradication of nasal carriage.

The Distribution and Drug Resistance Characteristics of Methicillin Resistant Staphylococcus aureous to be Public and Animal Health Burdon in Ethiopia: Systematic Review

The current meta-analysis was aimed to analyze the prevalence rate of MRSA in S. aureus isolates from different sources of samples in Ethiopia. The multidrug resistance pattern of the pathogen was also one of the outcome of interest of the analysis. The data for the current study were extracted from original research articles published in journals indexed in PubMed databases, accessed online from 12th to 14th December 2021, whose pdf were freely downloadable, English language articles, and conducted on MRSA prevalence in Ethiopia. The data were displayed on Excel spreadsheet, coded, exported to R statistical software and the pooled prevalence of MRSA was calculated per S. aureus isolates and analyzed at 95% CI. Accordingly, 79 eligible articles were selected for the meta-analysis. The result of the study revealed that 26930 samples have been collected from different specimens of which 4219 (15.65%) were S. aureus positive. Of the total S. aureus, 1695 were found MRSA strains and the overall pooled prevalence of MRASA per S. aureus isolates was 40%. In terms of the sources of the specimen, the pooled prevalence of MRSA in human, animal, food and environment were 38%, 15%, 77%, and 54% respectively and it was significantly higher in food and environment than in animal and human samples (p&lt;0.05). The analysis also showed that that MRSA was highly prevalent in patients than in health people (p&lt;0.05). Furthermore, the study revealed that MRSA was highly resistant to cefuroxime (100%), Tobramycin (100%), Neomycin (99%) and Penicillin (92%), Pipracilin (91%), Erythromycin (88%), Bacitracin(84%) and Amoxacilin-clavulanicacid (80%).-However, clindamycin (21%), chloramphenicol (22%), Amikacin (27%), vancomycin (20%), Knamycin (25%) and Ceftriaxone (30%) were antibiotic of relatively better effective against MRSA.

Prevalence and antibiotic susceptibility of clinical staphylococcus aureus isolates in various specimens collected from a tertiary care hospital, Hayatabad, Peshawar, Pakistan.

Staphylococcus aureus is a notorious Gram-positive, non-spore-forming, opportunistic bacterium that causes a variety of infections including bacteremia, endocarditis, pneumonia, skin and soft tissue infections, and several others. Also, the overuse and misuse of drugs attributed to the crises of multidrug resistance especially in MRSA. Objective: Therefore, the aim of this study was to determine the prevalence rate of MRSA, antimicrobial susceptibility profiles of S. aureus, MRSA, and MSSA isolates to a variety of commonly used antibiotics, and its multidrug resistant patterns. Methods: Samples were collected from the microbiology department of HMC Peshawar, Pakistan. Antibiotic susceptibility patterns were determined under CLSI and EUCAST guideline, 2021 by following the Kirby-Bauer disc diffusion method. Results: Out of 106 S. aureus clinical isolates, 83 (78.3%) isolates were identified as MRSA and 23 (21.7%) were MSSA. In MRSA high resistance was exhibited to Penicillin G and cefoxitin (100%), followed by erythromycin 84.34% and ciprofloxacin 79.52%. Meanwhile low resistance was observed to doxycycline 19.28% followed by chloramphenicol 14.46%, teicoplanin and linezolid 2.41% for each respectively. High sensitivity in MRSA isolates was exhibited to linezolid 97.59% followed by teicoplanin 95.18%, chloramphenicol 85.54%, doxycycline 80.72% and fusidic acid 74.70%. A total of n=94 (88.67%) isolates were characterized as MDR. Conclusions: In conclusion, the most effective antibiotics used to treat S. aureus infections were linezolid, teicoplanin, chloramphenicol, doxycycline, fusidic acid, and gentamycin. In addition, the current study also noticed a significant prevalence of resistance to several antibiotics, emphasizing the importance of antibiotic usage monitoring.

Tedizolid in vitro activity against Gram-positive clinical isolates causing bone and joint infections in hospitals in the USA, Europe, Latin America, and the Asia-Pacific region (2015-2019)

As bone and joint infections (BJIs) frequently require prolonged, systemic antibiotic use, tedizolid is an attractive candidate for BJI therapy in adults and children. Tedizolid activity was evaluated against 1,193 Gram-positive isolates causing BJI in American (USA), European (EUR), Latin American (LATAM), and Asian-Pacific (APAC) medical centers. Isolates consecutively collected from 2015 to 2019 were susceptibility tested by CLSI broth microdilution. Staphylococcus aureus (69.2%) was the most common pathogen with a 25.9% MRSA rate and tedizolid MIC50/90 of 0.12/0.25 mg/L (100% susceptible). Tedizolid exhibited MIC50/90 values of 0.12/0.12 mg/L (98.9% susceptible) for CoNS (7.5% of BJI), 0.12/0.25 mg/L for streptococci, and 0.25/0.25 mg/L for enterococci. Overall, high susceptibility rates (100.0%) for linezolid, daptomycin, and vancomycin were observed. In summary, tedizolid had potent in vitro activity against contemporary Gram-positive cocci causing BJI in adults and children in USA, EUR, LATAM, and APAC hospitals.

Microbiology of surgical site infections (SSIs) following skin cancer surgery.

Surgical site infections (SSIs) represent one of the most common and potentially preventable sources of morbidity and healthcare cost escalation associated with skin cancer surgery. There is a lack of data reporting organisms cultured from SSIs in skin surgery, with guidelines for antibiotic prophylaxis based on common skin pathogens rather than actual cultured organisms. In this study, we sought to define the cultured microbiology of SSIs specific to skin cancer surgery and test these against empiric treatment guidelines. All consenting patients presenting to the Auckland regional skin cancer treatment centre over a 6-month period were included. Patients receiving any form of antibiotics within a week prior to surgery were excluded. All wounds were assessed postoperatively, with clinically significant infections identified as those with a standardized wound infection score of 4 (range 0-7) and/or prescribed post-operative antibiotics within 3 weeks of surgery. Wound cultures were recorded. About 104 clinically significant SSIs were identified from 333 lesions treated, with cultures available in 27%. Cultured organisms included MSSA (79%), MRSA (14%), coagulase-negative Staphylococci (11%), and 'skin flora' (14%). Empiric guidelines inaccurately predicted effective treatment in 14% of cases, exclusively due to MRSA. To our knowledge this is the first comprehensive report of SSI microbiology following skin cancer surgery. The overwhelmingly predominant organisms were Staphylococcus sp. (76%), with the rate of MRSA approaching prevalence warranting empiric first-line treatment. These data help inform effective rationalized empiric antibiotic treatment, when indicated, for optimal outcome following skin surgery.

High Levels of Methicillin-Resistant Staphylococcus aureus Carriage Among Healthcare Workers at a Teaching Hospital in Addis Ababa Ethiopia: First Evidence Using mecA Detection.

BackgroundStaphylococcus aureus is a major human pathogen and causes healthcare and community-acquired infection. Data on the extent of MRSA colonization among health-care workers (HCWs) in sub-Saharan Africa are limited. Hence, we determined the burden of MRSA colonisation among HCWs and administrative staff in Tikur Anbessa Specialised Hospital (TASH), College of Health Sciences (CHS), Addis Ababa University, Ethiopia.MethodsUsing a cross-sectional study design, participants were screened for MRSA colonisation between June 2018 and August 2019 using nasal swabs. The swabs were analysed using standard laboratory methods including antibiotic resistance gene, mecA. Anonymised sociodemographic data were collected by pretested questionnaires to evaluate HCWs factors associated with MRSA carriage.ResultsA total of 588 HCWs and 468 administrative staff were screened for MRSA. Women were over-represented. Overall, 49.1% (289/588) of HCWs were nurses and 25% (117/468) of the administrative staff were cleaners or laundry workers. Overall, 138 S. aureus isolates were retrieved from the nasal swabs of both groups (16.3%, 96/588 from HCWs). The burden of MRSA colonisation was 4.8% (28/580, 95% CI: 3.1–6.5%) among HCWs compared to 0.2% (1/468, 95% CI: 0.18–0.6%) of administrative staff (p value <0.05). The majority of S. aureus and all MRSA isolates were resistant to penicillin. Isolates from HCWs were more resistant to tested antibiotics than administrative staff (P-value <0.05).ConclusionThis is the first report in Ethiopia on MRSA colonization using mecA and revealed that; (i) overall carriage rates of MRSA in HCWs are comparable with observations reported in some other countries and (ii) HCWs exhibit a higher burden of MRSA carriage than administrative staff. Our data support strategic screening of MRSA and antimicrobial stewardship for better intervention measures.

Reducing Staphylococcus aureus infections in the neonatal intensive care unit.

Our neonatal intensive care unit (NICU) saw an increase in Staphylococcus aureus (SA) infections-methicillin-resistant SA (MRSA) infections increased from 2.1/10,000 patient days (PD) to 5.1/10,000 PD, and methicillin-sensitive SA (MSSA) infections from 1.2/10,000 PD to 3.9/10,000 PD. This quality improvement project aimed to decrease the rates of SA infections to less than 2.0/10,000 PD, and to determine the rate of SA decolonization. Infection prevention interventions targeted patient factors (SA surveillance, patient cohorting, decolonization protocol), provider factors (provider cohorting, enhanced hand hygiene) and environmental factors (room structure, equipment optimization). The rates of MRSA and MSSA infections decreased to 0.6/10,000 PD and 0.7 infections/10,000 PD respectively. Persistent decolonization of SA was successful in 67% of colonized patients. Specific interventions targeting patient, provider, and environmental factors, including the implementation of a SA decolonization protocol, were successful in decreasing the incidence of SA infections in neonates.

Carriage of antibiotic-resistant bacteria and etiology of postoperative infectious complications in infants with congenital heart defects

Objective. To determine resistant microorganisms carriage, the frequency and etiology of postoperative infectious complications in high-risk infants with congenital heart defects (CHD). Materials and Methods. The retrospective analysis included 489 patients admitted for surgical treatment for CHD. The median age was 0.23 (0–12) months. Swabs were taken from the oropharynx and rectum for microbiological examination no later than 72 hours after admission (a total of 978 samples). The growth of resistant microorganisms (ESBL and/or carbapenemase-producing Enterobacterales, resistant non-fermentative Gram-negative bacteria, MRSA and VRE) was recorded. Results. Of 489 patients, 128 (26.2%) were colonized with resistant bacteria. The majority of patients were carriers of ESBL-producers (81.3%), in some cases (24%) with concomitant production of several carbapenemases. The rate of VRE carriage was 21.1%, in 8 cases – in combination with other resistant microorganisms. MRSA was detected in 1.6% of carriers, other multidrug-resistant microorganisms – in 3.9% of carriers. In early postoperative period, 145⁄489 (29.7%) patients developed infectious complications. The ventilator-associated respiratory tract infections were the most common. In most cases (73.8%) infectious complications were caused by ESBL producers, in 43.9% of cases those microorganisms also produced carbapenemases. Resistant non-fermentative Gram-negative bacteria caused postoperative infections in 4.8% of cases. The rates of MRSA and VRE in infants with infectious complications were 3.4% and 1.4%, respectively. There were no differences in the incidence of infectious complications in colonized and non-colonized patients – 42⁄128 (32.8%) versus 103⁄361 (28.5%), respectively (p = 0.6). Postoperative infectious complications were caused by resistant microorganisms in colonized patients significantly more often than in non-colonized patients – 41⁄42 (97.6%) and 82⁄103 (79.6%) cases, respectively (p = 0.008). Conclusions. It is confirmed the active process of the introduction of resistant microorganisms into the hospital with the possible development of complications of the corresponding etiology. Gram-negative bacteria with different mechanisms of antibiotic resistance present the greatest problem. In order to manage this process, it is advisable to screen hospitalizing patients with the implementation of the infection control measures.

206. Clinical and Molecular Characteristics of Community-associated Staphylococcus aureus Bacteremia in Injection and Non-injection Drug Users at a New York City Medical Center

Abstract Background The opioid epidemic has resulted in a dramatic resurgence of bacterial infections, most notably those due to Staphylococcus aureus (SA). We compared the demographic, clinical, and molecular factors of injection drug users (IDUs) and non-IDUs with SA bacteremia. Methods Patients with SA bacteremia were identified through a query of the electronic medical record EMR from January 2018 to December 2019 at a New York City medical center. All cases of community-associated (CA) SA bacteremia among adults with a history of active injection drug use were evaluated. Patients with positive SA blood cultures ≤ 72 hours of admission were considered CA. IDUs were identified with keyword searches and were deemed active if they had a history of use in the 12 months prior to admission. A randomly selected group of non-IDUs with CA SA bacteremia was used for comparison at a 4:1 ratio. Available SA isolates underwent Illumina whole genome sequencing (WGS). Using SRST2 multilocus sequence types (MLST), antimicrobial resistance genes and putative virulence factors were extracted. Results From January 2018 to December 2019, 669 patients with SA bacteremia were identified. 29 patients were active IDUs. Compared to 112 randomly selected non-IDUs, IDUs were significantly younger and more likely to be unstably housed (Table 1). Rates of MRSA were similar in IDUs (31%) and non-IDUs (32.1%). Endocarditis (44.8% vs 11.6%) and abscesses (27.6% vs 8.9%) were diagnosed more frequently in IDUs than non-IDUs. A positive hepatitis C antibody was strongly associated with SA bacteremia in IDUs (62.1% vs 6.3%, p&amp;lt; 0.001). WGS demonstrated comparable proportions of sequence types across IDUs and non-IDUs. ST8 accounted for the majority of infections in both groups (Table 2). MRSA bacteremia due to ST8 occurred in a higher proportion of IDUs (7/29, 24.1%) than non-IDUs (14/112, 12.5%). Conclusion IDUs with CA SA bacteremia have unique demographic and clinical features that differentiate them from non-IDUs. Endocarditis rates in IDUs are of particular concern. Use of these risk factors could allow hospitals to rapidly identify IDUs and offer them necessary medical and social services. WGS revealed a majority of MRSA bacteremia was due to one sequence type in IDUs (ST8). Further analysis of virulence genes in this cohort are ongoing. Disclosures Franklin D. Lowy, MD, GlaxoSmithKline (Advisor or Review Panel member)UpToDate (Other Financial or Material Support, Topic Writer and Editor) Anne-Catrin Uhlemann, MD, PhD, Merck (Grant/Research Support)