Coagulase-negative Staphylococci Research Articles

Epidemiology and temporal trends of infective endocarditis between 2006 and 2018 at a tertiary referral center

Abstract Introduction Despite modern diagnostics, targeted antibiotic therapy and surgical treatment the mortality rate of infective endocarditis (IE) remains high. In developed countries both the risk factors and pathogens have changed. Objective and methods In our retrospective study we analyzed the clinical and microbiological characteristics, short- and long-term all-cause mortality, and temporal trends of consecutive patients admitted with IE between 2006 and 2018. Results We included 537 cases in our study, the mean age was 55.9 ± 16.5 years (72.2% male). 325 (60.5%) cases were native left-sided IE, 14 (3%) cases were right-sided IE, 130 (24%) cases were prosthetic valve IE, 62 (11.5%) cases were intracardiac device-related IE and 6 (1%) other cases. The most common microorganisms were Staphylococci (n=175; 33%), including 104 cases of methicillin-sensitive Staphylococcus aureus (MSSA), 27 cases of methicillin-resistant Staphylococcus aureus (MRSA) and 44 cases of coagulase-negative Staphylococci. Streptococcus species were identified in 141 cases (26%), Enterococcus species in 88 cases (16%) and 72 cases (13%) were classified as blood culture-negative IE. In-hospital all-cause mortality was 14%, mortality at six months was 27%, at one-year was 31%, and at five-year was 45%. The incidence of MSSA infections increased over time (p=0.024), while coagulase-negative Staphylococci (p<0.001), and Streptococci (p=0.047) infections decreased. None of the observed mortality rates showed significant change over the study period. Predictors of mortality were advanced age (HR 1.37; p<0.001), impaired renal function (HR: 1.03; p<0.001), reduced ejection fraction on admission (HR 1.38; p<0.001), stroke (HR 1.74; p=0.001), and MRSA infection compared to Streptococci (HR 2.56; p=0.002). Conclusion During the observed 13-year period Staphylococci were the most common pathogens, with an increasing incidence of MSSA infection in our tertiary center. The mortality rate of IE remained high and showed no improvement over time.

Microbial specturm and antibiotic sensitivity of pocket swabs in ICD patients undergoing device replacement or lead revision surgery- findings from a ICD registry observational study

Abstract Introduction Infection is a serious complication of implantable cardioverter defibrillator (ICD) therapy, necessitating effective preventive measures during implantation or revision surgery. The intraoperative use of antibacterial envelopes containing rifampicin and minocycline has shown promising results in reducing infection, yet, it is expensive and not cost-effective. Gentamicin sponges might be an alternative to the antibacterial envelope, however its efficacy on targeting the specific microbial spectrum found in device infection must be further investigated. Aim of the study was to identify the bacterial species obtained from pocket swabs of ICD patients undergoing revision surgery, and assess their sensitivity to gentamicin, rifampicin and minocycline. Methods A total of 459 intraoperative pocket swabs were collected from consecutive ICD patients who underwent elective device replacement, system upgrade or lead revision between 2017 and 6/2023. The baseline characteristics were similar in both groups (Table 1). Results Out of the 459 swabs analysed: 416 (90.6%) were negative for microbial growth. The remaining 43 swabs (9.4%) were tested positive for microbial growth (Table 2). Coagulase-negative- staphylococci (CoNS) were the most commonly isolated bacteria, accounting for 56% of cases. Bacteria with available antibiograms exhibited a sensitivity of 92% to gentamicin, 96% to rifampicin and 96% to Minocycline (Table 2). Conclusion The antibiotic sensitivity of the bacteria obtained from the pocket swabs to gentamycin, rifampicin and minocycline was similar. Thus, gentamicin sponges might be an alternative to the antibacterial envelope in patients with ICD undergoing generator replacement or revision surgery.

Infective endocarditis on percutaneous aortic valve prosthesis: incidence, characteristics and comparison with endocarditis on surgically implanted aortic bioprostheses

Abstract Background Transcatheter aortic valve replacement (TAVR) has become a first-line therapeutic measure in patients with severe aortic stenosis, especially in selected patients who present a very high surgical risk; nevertheless, this technique is becoming increasingly widespread even among patients with a lower surgical risk. Infective endocarditis (IE) is an infrequent but very serious complication in patients undergoing TAVR implantation. The aforementioned generalization of this technique means that more and more patients are at risk of developing this complication which, in addition, seems to have some particularities with respect to endocarditis in other patients. Purpose The aim of our study was to analyze the incidence, clinical characteristics and mortality of IE in patients with TAVR, comparing them with IE in patients with surgically implanted prostheses (SAVR). Methods Observational, single-center, prospective cohort study including all cases of IE diagnosed and prospectively followed up in our center from 2008 to 2022, according to Duke or ESC diagnostic criteria, depending on the era. We identified cases of IE in patients with TAVR in this period and compared their characteristics with endocarditis in patients with surgical aortic prostheses. Results In our center 10 cases of IE have been diagnosed in patients with TAVR. Since 2008 this procedure has been successfully performed in 778 patients, which gives an incidence of 1.29% compared to 1.68% of its surgical counterpart with a total of 24 cases of IE. The clinical characteristics of these patients are shown in the table. With the exception of mean age (p= 0.006), there were no significant differences between the two groups. In approximately half of the cases the diagnosis was made early after valve replacement (<1 year after replacement). With respect to the causative microorganisms, the most prevalent agent was enterococci, followed by coagulase-negative staphylococci and staphylococcus aureus; in 17% of patients with SAVR the causative agent was not identified. The clinical evolution was similar in both groups, with a high proportion of severe complications and 50% of cardiac complications in the TAVR group. Half of the patients had a surgical indication at diagnosis, but only 50% underwent surgery. There were also no differences in mortality, which, nevertheless, was high, around 30%. Conclusions Despite the differences in mean age, no significant differences were found between the two groups. IE is an infrequent but serious complication in patients with prosthetic valves, with a high rate of serious complications and mortality regardless of its management.Baseline characteristics of patients

Investigation of Staphylococcus Spp and Coliform Bacteria Contamination Sources after Cleaning-in-Place in Production Lines of Dairy Factories in Türkiye.

Microorganisms detected on dairy factory surfaces after disinfection can cause product contamination, leading to economic losses and health hazards for consumers. In this study, the presence of Staphylococcus spp. and Coliform in a total of 450 samples taken from food-contact and non-contact surfaces (stainless steel, plastic, cloth, and tiles surfaces), raw milk and final product (white cheese, kashar cheese, butter, yogurt, and cream) samples in five dairy factories was investigated by conventional techniques. The isolates obtained were identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. In this study, a total of 54 Staphylococci (16.7% S. aureus and 81.5% coagulase-negative Staphylococci [CNS]) and 44 coliform isolates were identified at the species level. The most common CNS isolated by samples was S. epidermidis followed by S. saprophyticus, S. capitis, S. succinus S. carnosus. S. xylosus, S. sciuri, S. equorum, S. warneri, and S. hominis. Eighteen of the coliform isolates (41%) were identified as E. coli; 13 (29.5%) as E. cloacae; 3 (6.9%) as E. kobei, C. freundii, and K. oxytoca; 2 (4.5%) as K. pneumoniae; 1 (2.3%) as E. ludwigii and C. farmeri. The contamination rate of non-food contact surfaces (71.3%) was found to be higher than food contact surfaces (10.4%), and contaminated surfaces were found to be effective in product contamination. Study results show that some bacterial species obtained from raw milk, surfaces, and final products are factory specific and surface-associated bacteria are prominent in the product microbial profile.

Virulence characterization of Staphylococcus spp. isolated from mozzarella cheeses and cheese-slicers

Different species of the Staphylococcus genus can be found as contaminants in foods and may carry virulence factors that could potentially make them The enterotoxigenic potential ofpathogenic or transfer genes to other bacteria. Therefore, the aim of the present study was to isolate and identify species of Staphylococcus genus isolated from sliced mozzarella cheeses and cold-cut slicers and characterize biofilm formation in vitro, presence of enterotoxins and antibiotic resistance genes, and β-lactamase production. Sampling was carried out in 44 retail markets and isolates identified on species level. Resistance genes blaZ and mecA, as well as enterotoxin genes sea, seb, sec, and sed, were identified using PCR. Phenotypic evaluation of biofilm formation and detection of β-lactamase enzyme were also analyzed. Nine species of coagulase-negative Staphylococcus (CNS) were identified from 85 bacterial isolates. Of this total, 67.0% were positive for the presence of one or both antimicrobial resistance genes blaZ and mecA, while the β-lactamase enzyme was detected in 52.9% isolates. Regarding biofilm production, 48.2% of isolates were positive and 51.8% were negative. However, none of the isolates were identified with the enterotoxin genes. The results demonstrate the potential risk of cross-contamination, as biofilm-producing CNS could persist in the cheese retail environment, highlighting the danger of resistance genes transferring to other commensal or pathogenic bacteria.

Isolation and characterisation of novel lytic bacteriophages for therapeutic applications in biofilm-associated prosthetic joint infections

Abstract Prosthetic joint infections are devastating complications of joint arthroplasties. Without effective management, they can lead to limb amputation and even death. A significant proportion of these infections is caused by the primarily commensal Coagulase-negative Staphylococci pathogens, which form thick, antibiotic-resistant biofilms at the site of infection. Combinatorial therapy involving antibiotics and bacteriophages may represent a strategy to overcome resistance. Previous research indicates that as bacteria develop resistance to antibiotics, they often become more susceptible to bacteriophages. In this study, we produced a cocktail of novel bacteriophages and assessed their viability to eradicate nosocomial staphylococcal biofilms. Here, we used clinical isolates from prosthetic joint infections to isolate and identify four new bacteriophages from sewage effluent. These novel phages were characterized through electron microscopy and full genome sequencing. Subsequently, we combined them into a phage cocktail, which effectively re-sensitized biofilms to vancomycin and flucloxacillin. Notably, this phage cocktail demonstrated low cytotoxicity in vitro to human epithelial cells, even when used alongside antibiotic treatments. These findings highlight the potential of the phage cocktail as a tool to increase antibiotic treatment success in prosthetic joint infections.

Outcomes of infective endocarditis in patients with end-stage renal disease and dialysis in Spain: a population-based study

Abstract Background Patients with end-stage renal disease (ESRD), particularly those undergoing dialysis, have a significantly higher risk of developing infective endocarditis (IE) compared to the general population. ESRD is not only related to a higher risk of infection, but also to a worse prognosis in IE. However, most data regarding the epidemiology and outcomes of patients with ESRD and IE is derived from noncontemporary population-based studies with limited clinical variables and lack of complete microbiological information, or from retrospective single-center cohorts. Purpose The aim is to describe the clinical characteristics and outcome of patients with IE and ESRD in Spain, compared to patients without ESRD, and to investigate potential differences between patients undergoing dialysis and the rest of patients with ESRD. Methods Retrospective observational population-based study. A total of 9,008 episodes of IE between 2016 and 2019 were analysed using information from the Spanish Minimum Basic DataSet. 428 patients had ESRD, of whom 332 were undergoing dialysis. A multivariable and multilevel logistic model was developed to evaluate the association of different variables with in-hospital mortality in ESRD patients. Results Compared to patients without ESRD, those with ESRD were younger, had more comorbidities, and had a higher incidence of Staphylococcus aureus (31.8% vs. 18.4%; p <0.001) and coagulase-negative staphylococci infections (19.2% vs. 14%; p =0.006). In terms of in-hospital complications, septic shock was more frequent in patients with ESRD (12.1% vs. 8.9%; p=0.007). Furthermore, ESRD patients underwent cardiac surgery less frequently than patients without ESRD (12.6% vs. 19.6%; p <0.001) and had significantly higher in-hospital mortality (33.4% vs. 26.9%; p =0.003). When comparing patients undergoing dialysis with the rest of ESRD patients, it was observed that those on dialysis had more comorbidities and a higher proportion of Staphylococcus aureus infections (36.1% vs. 16.7%; p <0.001). No differences were found in observed in-hospital mortality between patients on dialysis and the rest of ESRD patients. The multilevel analysis revealed that dialysis was not an independent risk factor for in-hospital mortality in patients with ESRD. Cardiac surgery was also not independently associated with higher in-mortality in ESRD patients. Conclusions Patients with ESRD and IE have a different clinical and microbiological profile than other patients with IE. Moreover, they undergo cardiac surgery less frequently and have significantly higher in-hospital mortality. Dialysis treatment and cardiac surgery were not independent risk factors for mortality in ESRD patients with IE.

Epidemiology of Bacteremia in Patients with Hematological Malignancies and Hematopoietic Stem Cell Transplantation and the Impact of Antibiotic Resistance on Mortality: Data from a Multicenter Study in Argentina

The epidemiology of bacteremia and the antibiotic resistance profile (ARP) of Gram-negative bacilli (GNB) in hematological malignancies (HM) and hematopoietic stem cell transplant (HSCT) patients may differ according to geographic region. In addition, multidrug-resistant organisms (MDROs) may impact mortality. This is a prospective, observational, and multicenter study. The first episodes of bacteremia in adult patients with HM or HSCT were included. The risk factors for 30-day mortality were identified. One thousand two hundred and seventy-seven episodes were included (HM: 920; HSCT: 357). GNB were isolated in 60.3% of episodes, with Enterobacterales (46.9%) and P. aeruginosa (8.5%) being the most frequent. Gram-positive cocci were isolated in 41.9% of episodes, with coagulase-negative staphylococci (19.8%) and S. aureus (10.4%) being the most frequent. MDROs were isolated in 40.2% (24.4% GNB). The ARP of GNB in patients with HM vs. HSCT was cefepime: 36.8% vs. 45.7% (p = 0.026); piperacillin–tazobactam: 31.05% vs. 45.2% (p < 0.0001); carbapenems: 18.9% vs. 27.3% (p = 0.012); and aminoglycosides: 9.3% vs. 15.4% (p = 0.017), respectively. Overall mortality between patients with HM and HSCT was 17.5% vs. 17.6% (p = 0.951), respectively. The risk factors for mortality were relapsed and refractory underlying disease, corticosteroids use, respiratory source, septic shock, and GNB resistant to meropenem, while 7-day clinical response was a protective factor for survival. Bacteremia was frequently caused by GNB, with a large proportion of MDROs and a high level of antibiotic resistance, especially in patients with HSCT. Carbapenem-resistant GNB bacteremia was associated with a significant increase in mortality.

MIC trends of vancomycin and teicoplanin among methicillin resistant CoNS isolates from new born blood cultures in a tertiary care centre in Southern India.

Coagulase-negative-Staphylococci (CoNS) are important etiological agent of bacteraemia in newborn babies. Methicillin resistant CoNS infections have only limited treatment options. The antimicrobial susceptibility pattern of Methicillin Resistant CoNS isolates from newborn blood cultures was studied with special reference to MICs of Vancomycin and Teicoplanin. The study population included Methicillin Resistant Coagulase Negative Staphylococcal isolates (MRCoNS) from newborn blood cultures, during a one-year period. Minimum inhibitory concentration (MIC) of Vancomycin and Teicoplanin in Methicillin resistant CoNS isolates was determined by macrobroth dilution method as per CLSI guidelines and by automated methods. Coagulase Negative Staphylococci were the etiological agent in 73.7% (n=56) cases of neonatal bacteremia. Methicillin resistance in newborn CoNS was found to be 58.9%. All the MRCoNS isolates had vancomycin and teicoplanin MICs in the susceptible range. There were MRCoNS isolates with MICs in the upper limit of susceptible range for both vancomycin and teicoplanin, which can result in poor clinical response. Continuous large scale multi-centre surveillance studies with special attention to study the MIC pattern of the high-end anti-MRSA agents like vancomycin, teicoplanin, linezolid are to be carried out. This will help the clinicians to judiciously prescribe the antibiotics, which is very essential for antimicrobial stewardship.

New 2023 ESC Guidelines for the management of endocarditis

A succinct summary of the 2023 guidelines on the management of infectious endocarditis of the European Society of Cardiology is presented. Main new aspects are (1) the importance of treating complicated endocarditis at a hospital with an endocarditis team and cardiac surgery, (2) a less restrictive recommendation for antibiotic prophylaxis, which now favors an individualized indication in patients with intermediary risk, e.g. bicuspid aortic valve and degenerative or rheumatic native valve disease, undergoing orodental interventions, while there is a clear recommendation for prophylaxis in high-risk patients (e.g. having prosthetic valves). (3) In patients with left-sided endocarditis caused by streptococci, enterococcus faecalis, staphylococcus aureus, or coagulase-negative staphylococci, who are stable after at least 10 days of in-hospital intravenous appropriate antibiotic therapy, step-down ambulatory (oral or parenteral) further antibiotic therapy is recommended.

Distribution of bacterial pathogens and antimicrobial resistance in cows with clinical mastitis in a dairy farm, Türkiye

This study aimed to identify the pathogens causing clinical mastitis (CM) and their resistance levels to six common antimicrobials in a dairy farm in Turkey. A total of 973 CM milk samples were cultured and a Kirby-Bauer disc diffusion method was performed for antimicrobial susceptibility. While 64.0% (623/973) of CM samples were culture-positive, 36.0% (350/973) of CM samples yielded no growth. Escherichia coli was the most frequently isolated pathogen (36.3%), followed by coagulase-negative staphylococci (8.3%), Streptococcus dysgalactiae (7.3%), Staphylococcus aureus (3.1%), Streptococcus uberis (1.5%), Enterococcus spp. (1.4%), Mycoplasma spp. (1.4%), Streptococcus agalactiae (0.7%), and Corynebacterium spp. (0.4%). Antimicrobial resistance was higher (P > 0.01) to amoxicillin/clavulanic acid (AMC, 32.3%) than that to enrofloxacin (ENR, 23.4%), cefoperazone (CFP, 17.9%), cefquinome (CEQ, 17.7%), penicillin G (P, 15.2%), and gentamicin (CN, 3.6%) in culture-positive 642 isolates. For E. coli isolates, percentage of resistance to AMC, ENR, CFP, CEQ, P, and CN was 37.7, 30.6, 24.4, 23.2, 5.9, and 1.1%, respectively. Resistance to AMC (31.2%) and P (46.3%) was higher in CNS than Strep. dysgalactiae isolates (1.5% and 12.7%), respectively. Multidrug resistance was detected in 34 E. coli isolates (9.6%), 7 CNS isolates (8.6%), and 2 Strep. dysgalactiae (2.8%). In conclusion, the higher identification of E. coli demonstrated the higher risk of environmental microorganisms for CM in this study. Higher resistance to commonly used five of six antimicrobials showed the requirement of frequent bacteriological and antimicrobial susceptibility tests for CM. Thus, these implementations could increase treatment efficacy in cows and reduce antimicrobial resistance.

Microbial Sampling and Analysis Taken from Fingerprint System Devices Located at Al-Yarmouk Teaching Hospital in Baghdad - Iraq

Biometric devices (BDs) are nowadays common in use for a variety of purposes. This system involves physical contact between the skin and surface of the device, which is likely to be contaminated by microorganisms of multiple users. However, it can be a source of multiple microbiological contaminations. This study was done at AL-Yarmouk Teaching Hospital-Baghdad- Iraq, during the period started from 15th November 2023 till 15th March 2024. It was designed to find out the most common bacteria and fungi that might contaminate the fingerprint devices and performing antimicrobial susceptibility tests. Forty-six sterile swab samples taken from Twenty-three fingerprint system devices distributed in twelve different hospital departments. From each device we took two swabs, one before sterilization other after, and tested sensitivity patterns against 16 antimicrobials. Four Gram positive bacteria scored on fingerprint devices, in Medicine, Surgery, Orthopedics and Obstetrics & Gynecology departments represented by Coagulase-negative Staphylococci (CoNS). Response to sensitivity test for antibiotics, especially Moxifloxacin, Linezolid, Teicoplanin, Vancomycin, Tigecycline and Rifampicin, 100%, as well other antibiotics but in varying degrees, and not any type of fungi were isolated. In conclusion, Gram positive bacteria population was the most common organisms, and highly response in varying degrees to the most Sixteen antibiotics used in sensitivity test, however, should proper maintenance and educational practices must be applied to minimize contamination.

EFFECT of daily antiseptic bathing with octenidine on ICU-acquired bacteremia and ICU-acquired multidrug-resistant organisms: a multicenter, cluster-randomized, double-blind, placebo-controlled, cross-over study.

Antiseptic bathing has garnered attention in an effort to reduce hospital-acquired infections. Previous studies have shown the efficacy of antiseptic bathing in high-risk environments, such as intensive care units (ICUs), using chlorhexidine. In this study we aimed to evaluate the effectiveness of octenidine as a potential alternative due to its established popularity and widespread use in Europe. We compared the rates of ICU-acquired primary bacteremia and ICU-acquired multidrug-resistant organisms (MDROs) in a multicenter, cluster-randomized, double-blind, placebo-controlled, cross-over study using octenidine-impregnated and placebo washcloths. On 44 ICUs in 23 hospitals throughout Germany, we compared individual ICUs with themselves over two 12-month time periods. All data were obtained digitally via hospital information systems as individual ward-movement data and microbiological test results; both endpoints were algorithmically derived. 104,039 ICU episodes from 93,438 patients with 712,784 microbiological test results were analyzed, thereby detecting 1508 cases of ICU-acquired primary bacteremia and 1871 cases of ICU-acquired MDRO. Bathing with octenidine-impregnated washcloths prevented ICU-acquired primary bacteremia; a risk reduction of 17% was seen homogeneously across all participating ICUs (adjusted hazard ratio (HR) 0.83, 95% confidence interval (CI) [0.75; 0.92], p = 0.0003). This reduction affected predominantly coagulase-negative staphylococci (53%) and enterococci (17%). However, no intervention effect was seen for ICU-acquired MDROs (adjusted HR 0.98, 95% CI [0.83; 1.15]). Heterogeneity among intra-ICU intervention effects on MDRO acquisition was substantial. Antiseptic bathing with octenidine may be effective in preventing ICU-acquired primary bacteremia, particularly due to Gram-positive bacteria and common skin commensals.

Antibiotic Susceptibility among Infective Endocarditis Population: Syndromic Antibiogram Evaluation at Indonesian National Cardiovascular Center

Infective Endocarditis (IE) is a life-threatening disease with a high mortality rate (25%). Laboratory approaches to support the diagnosis of IE especially blood and/or cardiac vegetation culture, are crucial for providing definitive therapy. However, negative culture is frequently observed, therefore empirical use of antibiotics seems unavoidable and may lead to increasing antimicrobial resistance. This study aims to observe the prevalence of antibiotic susceptibility among the IE population using the WISCA approach. This retrospective study observed medical record data of all inpatients diagnosed with IE according to ICD-10 at Cardiovascular Center Harapan Kita Hospital (NCCHK) between January 2018 and December 2022. Patient data were combined with bacterial identification and antibiotic susceptibility test data from the laboratory information system, and evaluated based on period (year). A total of 67,858 inpatients and 1.1% (n=772) were diagnosed with IE. Successful culture growth (blood and/or cardiac vegetation specimen) was between 36.8% and 70% annually. Streptococcus viridans group (82/237, 34.6%) and Coagulase-negative Staphylococci (57/237, 24.1%) were dominantly observed among the IE population. Low susceptibility among Penicillin (34.3%) towards Gram-positive bacteria, as first-line treatment option in IE. Meanwhile, high susceptibility range was observed in Ceftriaxone (95.7%), Gentamicin (80.4%), Rifampicin (84.4%), and Vancomycin (98.7%) as second-line treatment in IE. Despite the low prevalence, the occurrence of antimicrobial resistance in IE has become a priority concern. Continuing the syndromic antibiogram is mandatory to assist the trend of empirical antibiotic usage and refine the established local treatment guidelines.

Assessment of Antimicrobial Resistance and Susceptibility Pattern of UTI-causing Microorganisms in Southern Punjab, Pakistan

Background: Bacterial resistance against antibiotics has become a global challenge and measures are needed to stop this. The aim of this study is to highlight this problem and to determine the antibiotic susceptibility pattern of organisms in Southern Punjab, Pakistan. Method: This descriptive cross-sectional study was conducted in Sheikh Zayed Medical Hospital, Rahim Yar Khan. The urine samples obtained from 4 different wards were sent for culture and sensitivity analysis. 9 antibiotics (Nitrofurantoin, Fosfomycin, Ciprofloxacin, Ceftriaxone, Trimethoprim-Sulfamethoxazole, Norfloxacin, Linezolid, Amoxicillin, and Imipenem) were tested against 5 isolated strains of uropathogens using Kirby Bauer disk diffusion test. The sensitivity reports were obtained, and data points were entered into a spreadsheet and analysed using SPSS. Results: Out of 101 samples of uropathogens that showed positive growths (42.08%), 53 (52.4%) were from male patients and 48 (47.5%) positive growths were from females. Escherichia Coli had the highest positive growths (58%) followed by Pseudomonas (19%) Klebsiella (13%), Staphylococcus Aureus (7%) and Coagulase-negative staphylococci (3%). Imipenem was the most sensitive drug whereas the highest resistance by organisms was developed against TMP-SMX. No significant association(p>0.05) was found between any of the anti-microbial drugs and Escherichia coli, gram-positive uropathogens, and gram negative uropathogens. Conclusion: The high increasing rate of broad-spectrum antibiotics resistance suggests that diagnostic and culture tests should be encouraged in hospitals. Based on these test results, appropriate antibiotics should be prescribed. The limitations include the inability to distinguish between nosocomial and community-acquired urinary tract infections and also did not consider other demographic factors like age.

Antibiotic Resistance Pattern of Pathogens Isolated from Pediatric Patients during and after the COVID-19 Pandemic.

Background/Objectives: The present study aims to highlight the possible significant changes due to the COVID-19 pandemic in the resistance of pathogens involved in cases of pediatric infections. Methods: This study included children hospitalized in the Pediatric Intensive Care Unit, Surgery and Pediatrics from a tertiary teaching hospital, during and after the COVID-19 period (2020-2023). Results: The research included 845 samples collected during 2020-2023, from 685 pediatric patients. A total of 937 bacterial isolates were obtained, of which 509 isolates (54.32%) were Gram-negative bacteria. Around 30% of all the pathogens were multidrug-resistant (MDR), with a statistically significant increase post-pandemic, in the case of the MDR Escherichia coli strains (p < 0.05). A very high percentage of MDR Acinetobacter spp. isolates was found, with an important, but not statistically significant, increase in the post-pandemic period. The highest percentage of the MDR Gram-positive pathogens was registered in the case of S. aureus strains (31.80%). Over 20% of the Coagulase-negative Staphylococci (CoNS) strains isolated between 2020 and 2023 were MDR, with an important increase in the post-COVID-19 period. The proportion of carbapenem-resistant Gram-negative pathogens significantly decreased in the post-COVID-19 period compared with the COVID-19 period (p < 0.05), especially in the case of the Klebsiella spp. strains. Conclusions: Our findings revealed the increase in the post-COVID-19 period of the prevalence of MDR strains of Acinetobacter spp., CoNS, and Escherichia coli isolated in pediatric patient samples and a significant decline in the trend of the carbapenem-resistant Gram-negative pathogens, which may be due to the testing rate and to the specific pathology of the pediatric patients hospitalized in the two periods.

Bloodstream infections in a Brazilian Pediatric Tertiary Oncology Hospital: 30-month analysis regarding the classification of the infection, distribution of microorganisms and their resistance profile

Abstract Background Infections are a major cause of morbidity and mortality in pediatric oncology patients during their treatment. Bloodstream infections are the main site of infection in these patients. Bacteremia in these patients can be secondary to a primary infectious focus, result from central line associated bloodstream infections (CLABSIs) or mucosal barrier injury laboratory-confirmed bloodstream infection (MBI-LCBI). Methods Descriptive study of bloodstream infections in pediatric patients undergoing oncological treatment and hematopoietic stem cell transplantation in a tertiary pediatric oncology hospital in Brazil from January 1st, 2021 to June 30th, 2023. Infections were classified according to the Centers for Disease Control and Prevention/ National Healthcare Safety Network (CDC/NHSN) criteria into CLABSIs, MBI-LCBIs and secondary bloodstream infections. Among the bloodstream infections that met CDC/NHSN criteria for CLABSI, were analyzed separately those who also met the criteria of catheter-related bloodstream infection (CRBSI) according to Infectious Diseases Society of America (IDSA). Results During this period were diagnosed 335 episodes of bloodstream infection (123 episodes in 2021, 150 in 2022 and 62 episodes in the first 6 months of 2023). There were 378 microorganisms isolated. These infections were classified into: 35% CLABSIs, 27% MBI-LCBIs, 23% CRBSIs, and 15% secondary bloodstream infections. Among the CLABSIs, the most common microorganisms were non-fermenting gram negative bacilli (NFGNB) 38%, enterobacteriaceae 35% and coagulase-negative staphylococcus (CoNS) 11%. Between CRBSIs, there were 31% enterobacteriaceae, 22% CoNS and 19% NFGNB. Among the MBI-LCBIs there were 66% enterobacteriaceae and 23% group viridans streptococci (VGS). Streptococcus pneumoniae (33%) was the most common microorganism in secondary infections followed by Staphylococcus aureus (17%). Assessing all infections together, the main enterobacteriaceae were Klebsiella spp. (40%) and only 50% of them were sensitive to cefepime while 10% were carbapenems resistant. Among NFGNB, 13% of Pseudomonas spp. and 5% of Acinetobacter spp. were carbapenems resistant. Between the gram-positive bacteria, 77% of the S. aureus were methicillin sensitive, the same percentage of the VGS were sensitive to cefepime. Conclusion Among bloodstream infections, there were a predominance of CLABSI followed by MBI-LCBIs. Antimicrobial resistance between gram-positive bacteria, is of little concern in our institution. In the case of gram-negative bacteria, resistance to cefepime is becoming worrying among enterobacteriaceae.

Antibiotic Overuse in Pediatric Patients Hospitalized with RSV, COVID-19, and Influenza

Abstract Background Children hospitalized with viral respiratory tract infections (RTIs) are often treated with antibiotics due to concern for bacterial co-infection, although most do not have concurrent bacterial infections. This practice leads to unnecessary antibiotic treatment, which can lead to development of resistant bacteria and adverse events. The extent of antibiotic overuse in hospitalized children with community-onset viral RTI has not been well-quantified in recent years and may have worsened during the COVID-19 pandemic. The objectives of this study were to quantify and compare the extent of antibiotic overtreatment and to determine predictors of antibiotic use post-COVID-19 pandemic in children hospitalized with RSV, COVID-19, and influenza. Methods We performed a single center retrospective study evaluating percentages of antibiotic use and bacterial co-infection among children and adolescents aged &amp;lt;19 years old, hospitalized with respiratory syncytial virus (RSV), influenza, or SARS-CoV-2 between April 2020 and May 2023. Bacterial infection was defined as growth of bacteria from any specimen source, including blood, urine, pleural fluid, cerebrospinal fluid, and respiratory secretions, excluding common contaminants like coagulase-negative Staphylococci. Predictors of antibiotic treatment were determined using multivariable logistic regression. Results During the study period 1,718 patients were included (1022 with RSV, 188 with influenza, 535 with COVID-19). RSV patients were younger and more likely to be in the ICU than influenza or COVID-19 patients. The overall proportion of patients with culture-confirmed bacterial co-infection was low at 8% and did not differ greatly by virus type (8% for influenza, 6.9% for RSV, 10.3% for COVID-19, p=0.03). The proportion of children receiving antibiotics was higher for influenza than for other viruses (60.6% for influenza, 41.2% for RSV, and 48.6% for COVID-19, p &amp;lt; 0.001). Among patients with the lowest severity of illness (with normal inflammatory markers [PCT &amp;lt;0.5 ug/mL or CRP &amp;lt;50 mg/L] and not admitted to the ICU), 7.3% had a culture-confirmed bacterial infection while 48.1% received antibiotics. Independent predictors for receiving antibiotics were elevated inflammatory markers (C-reactive protein or procalcitonin), having &amp;gt;3 comorbidities, mechanical ventilation, and influenza diagnosis. Conclusion In children hospitalized with community-onset viral RTIs, antibiotic treatment is substantially higher than the burden of culture-confirmed bacterial infection, suggesting antibiotic overuse. Antibiotic use was greater for patients with influenza than for those with RSV or COVID-19. Antibiotic overuse was estimated to occur in over 40% of patients with low severity of illness. Stewardship programs can use this data to design interventions to promote more judicious antibiotic use. Figure 1. Rates of bacterial co-infection and antibiotic utilization among patients hospitalized with influenza, RSV, and COVID. Blue, percentage of patients who had a culture-confirmed bacterial infection; orange, percentage of patients who received any antibiotics; green, percentage of patients who received &amp;gt;3 days of antibiotics.

Molecular characterization and genotype of multi-drug resistant Staphylococcus epidermidis in nasal carriage of young population, Mahasarakham, Thailand.

Staphylococcus epidermidis, a coagulase-negative staphylococcus, is a prevalent skin commensal that has increasingly been recognized as a significant pathogen, particularly in hospital environments, where it is associated with device-related infections. The emergence of multi-drug resistance and its ability to form biofilms complicate the clinical management of infections caused by this organism, posing a growing public health concern. This study aimed to investigate the nasal carriage of S. epidermidis among healthy young individuals and to analyze its antibiotic resistance patterns, resistance genes, and biofilm formation capabilities. Nasal swabs were collected from 40 undergraduate students at Mahasarakham University, Thailand, aged between 20 and 22 years. A total of 38 isolates were confirmed as S. epidermidis through both phenotypic and molecular characterization. Antibiotic susceptibility testing demonstrated resistance to various classes of antimicrobials, including beta-lactams, macrolides, and tetracyclines. Notably, five isolates exhibited methicillin resistance S. epidermidis (MRSE). Resistance genes, such as mecA, ermA, tetM, tetL, and tetK, were identified across the isolates, contributing to the observed resistance profiles. Biofilm formation assays revealed that most isolates displayed weak to moderate biofilm formation, with only one isolate demonstrating strong biofilm-forming capacity. Genetic analysis indicated a significant correlation between biofilm formation and the presence of the icaA gene, which is crucial for biofilm production. This study suggests the necessity for ongoing surveillance of nasal carriage of S. epidermidis to enhance understanding of its role in the dissemination of antimicrobial resistance and biofilm-associated infections, particularly within healthcare settings.

Characterization of Chlorhexidine Resistance Among Clinical Isolates of Coagulase-Negative Staphylococcus Species in a Tertiary Care Center, Chennai.

Background Coagulase-negativeStaphylococci(CoNS) are potential pathogens and are often associated with healthcare-associated infections (HAIs). Chlorhexidine (CHX) is the most widely used antiseptic to reduce colonization and infection by allStaphylococci, including CoNS. Resistance to CHXamong CoNS has been observed over the past few years, consequent to its widespread use. Phenotypic tolerance or reduced susceptibility to CHX is conferred by plasmid-mediatedqacgroup of genes, mainlyqacA/Bandsmr, which cause activation of efflux pumps over the bacterial cell wall. This study aims to characterize the phenotypic and genotypic resistance exhibited by CoNS species against CHX. Methods After ethical approval, 148 consecutive, non-repetitive isolates of clinically significant CoNS species of hospitalized patients, isolated from blood samples and exudative specimens, were included in the study. Speciation was performed by conventional biochemical identification and automated methods. Antimicrobial susceptibility testing was performed by disc diffusion technique and for vancomycin by minimum inhibitory concentration (MIC) determination, as per Clinical Laboratory Standards Institute (CLSI) M-100 2023 guidelines. Methicillin resistance was detected using a cefoxitin disc. MIC for CHX was performed by agar dilution method; reduced susceptibility was considered when MIC to CHX ≥4 µg/mL. The simplex polymerase chain reaction (PCR) was carried out with suitable controls to detectqacA/Bandsmr. Statistical analysis was conducted to determine the association ofqacA/Bandsmrgenes with MIC of CHXin the study isolates. Results Fifteen different species of CoNS were obtained from clinical samples. A high percentage of resistance was observed against various classes of antibiotics. Methicillin resistance was observed in 69.6% (103/148) of isolates. Of 148 CoNS, 52.7% (78/148) of isolates exhibited reduced susceptibility to CHX with an MIC ≥4 µg/mL. These isolates exhibited a higher percentage of methicillin resistance (75.6%, 59/78). By PCR, 34.5% (51/148) of isolates carried either or both genes. GeneqacA/Bwas solely detected in 27.02% (40/148) of isolates, of which 14 were CHX-tolerant and the remaining 26 were CHX-susceptible. Genesmrwas solely detected in 4.1% (6/148) of isolates comprising three isolates each in CHX-tolerant and susceptible categories.There were 3.4% (5/148) of isolates that harbored bothgenes, of which only one isolate was CHX-susceptible, while the other four were CHX-tolerant. A proportion of isolates that were phenotypically tolerant to CHX did not carry either or both genes. A significant statistical association was found between reduced susceptibility to CHX and the presence of antiseptic resistance genesin the study isolates (p-value=0.033942). Conclusion To our knowledge, this is the first study from South India to investigate CHX resistance among CoNS using phenotypic and genotypic methods. The rise of antiseptic resistance among CoNS is an emerging threat to current infection control practices. The presence ofqacA/Bandsmrgenes, especially in CHX susceptible isolates, is concerning since these resistance genes are located on transferable plasmids, and the isolates can develop resistance eventually upon exposure to CHX.