Bacteremia Infection Research Articles

In vitro efficacy of levonadifloxacin against methicillin-resistant Staphylococcus aureus (MRSA) including hVISA isolates collected across India.

Vancomycin has been the preferred treatment for MRSA infections. However, newer drugs are necessary due to the increasing prevalence of MRSA isolates that are less susceptible to vancomycin. Levonadifloxacin and its prodrug alalevonadifloxacin, novel quinolones with broad spectrum anti-MRSA activity. They are approved in India for the treatment of skin and soft-tissue infections, bacteraemia, and diabetic foot infections. A total of 456 MRSA (Methicillin-resistant Staphylococcus aureus) isolates, including 333 isolates from JIPMER and 123 isolates from other tertiary care centers collected between January to December 2022, underwent susceptibility testing to levonadifloxacin by disc diffusion method. The study isolates included 29 h-VISA. Fifty one blood isolates were also subjected to E-test and their results were compared to the gold standard, broth micro dilution (BMD). All 456 isolates were found to be susceptible to levonadifloxacin by disc diffusion. Levonadifloxacin demonstrated potent activity against MRSA strains isolated from blood (n=51) with an MIC50 and MIC90 of 0.38 and 0.5μg/mL by E-test, respectively. Similarly, it demonstrated an MIC50 and MIC90 of 0.5 & 1μg/ml by BMD. The present study demonstrated 100% susceptibility to levonadifloxacin among the tested isolates of MRSA, highlighting its promising clinical potential for treating infections caused by this organism. Furthermore, the study recorded a concordance of 100% between disc diffusion and Etest method with BMD, indicating the reliability of these methods.

COMPARISON OF CLINICAL CHARACTERISTICS OF STAPHYLOCOCCUS AUREUS INFECTION IN ELDERLY AND YOUNGER ADULT PATIENTS IN KURDISTAN REGION. IRAQ

The study aimed to determine the clinical characteristics and outcomes of Staphylococcus aureus infections are different in elderly patients as compared with younger adults, the study started from January 2021 to December 2022, the samples were collected from male and female patient of 2 hospitals in Zakho and Duhok cities, were stratified into two groups by age, those 60 years or older were considered ‘elderly’ and those aged 15 to 59 years were defined as a younger ‘. Of 481 patients with an S. aureus infection. 249 (51.67) were classified as younger, while incidence rates of elderly patients were 232 (48.33). Pneumonia was the most common S. aureus infection in the younger group and skin and soft tissue infection, bacteremia infection, Bone and joint infection, Surgical site infection and endocarditis infection was the most common in the younger group comparative with the elderly group, Old age (60 years) was confirmed to be a strong independent risk factor for death in the entire study population after adjustment for confounding variables. And the clinical Characteristics in elderly and younger patients with Staphylococcus aureus infection. was incidence most common in the younger group comparative with the elderly group rates. KEYWORDS: Staphylococcus aureus Aged. Infection, outcomes, Clinical characteristics

Pseudomonas aeruginosa alkyl quinolone response is dampened by Enterococcus faecalis.

While we now appreciate that many infections are polymicrobial, we understand little of the specific actions between a given set of microbes to enable combinatorial survival and pathogenesis. The bacteria Pseudomonas aeruginosa and Enterococcus faecalis are both prevalent pathogens in wound, urinary tract, and bacteremic infections. While P. aeruginosa often kills other species in standard laboratory culture conditions, we present here that E. faecalis can be reliably co-cultured with P. aeruginosa. We specifically detail that ornithine produced by E. faecalis reduces the Pseudomonas quinolone signal response of P. aeruginosa. This reduction of the Pseudomonas quinolone signal response aids E. faecalis growth.

Association of febrile neutropenia episodes and blood product transfusions in children with acute leukemia.

Transfusion is vital supportive therapy in leukemias, but has significant potential febrile complications. In this study, we aimed to reveal the possible effects of blood product transfusions on febrile neutropenia episodes (FNEs) in children with acute leukemia. We obtained the relevant clinical and laboratory data from the medical records.Transfusions of red blood cell (RBC), platelet (PLT), and fresh frozen plasma (FFP) administered during FNE were recorded in detail. A total of 80 children with acute leukemia were included. A total of 235 FNE were investigated and the median age at first FNE was 4.72 years. At least one blood product transfusion was administered in 80.9 % (n = 190) of the patients with FN. The need for RBC, PLT, and total transfusions was higher in patients with AML and who were > 4 years-old. Bacteremia, gram-negative bacteria, and polymicrobial infections were more frequent in patients who received PLT transfusions. Complications were increased in patients who had ≥ 3 transfusions and had received multiple FFP and pooled PLT transfusions. Patients who received pooled PLT during previous FNE had an increased risk of death. Complications were more frequent, neutrophil count was lower, durations of neutropenia and medical treatment were longer in patients who had ≥ 3 transfusions.Bacteremia, gram-negative bacteria, and polymicrobial infections were more common in children who received PLT transfusions. Therefore, patients who need multiple transfusions, especially PLT and FFP transfusions, should be closely followed up during their FNE in terms consequences of transfusion as well as severity of underlying infection.

Selective decontamination of the digestive tract in a burns unit reduces the incidence of hospital-acquired infections: A retrospective before-and-after cohort study

ObjectiveTo evaluate the effect of selective decontamination of the digestive tract (SDD) on hospital-acquired infections (HAIs) in patients with acute burn injury requiring admission to a Burns Unit (BU). DesignRetrospective before-and-after cohort study, between January 2017 and June 2023. SDD was implemented in March 2019, dividing patients into two groups. SettingFour-bed BU, in a referral University Hospital in Spain. PatientsAll the patients admitted during the study period were eligible for analysis. Patients who died or were discharged within 48hours of admission, and patients with an estimated survival less than 10% not considered for full escalation of therapy were excluded. InterventionSDD comprised the administration of a 4-day course of an intravenous antibiotic, and an oral suspension and oral topical paste of non-absorbable antibiotics during the stay in the BU. Main variable of interestIncidence of HAIs during the stay in the BU. Secondary outcomes: incidence of specific types of infections by site (bacteremia, pneumonia, skin and soft tissue infection) and microorganism (Gram-positive, Gram-negative, fungi), and safety endpoints. ResultsWe analyzed 72 patients: 27 did not receive SDD, and 45 received SDD. The number of patients who developed HAIs were 21 (77.8%) and 21 (46.7%) in the non-SDD and the SDD groups, respectively (p=0.009). The number of hospital-acquired infectious episodes were 2.52 (1.21–3.82) and 1.13 (0.54–1.73), respectively (p=0.029). ConclusionsSDD was associated with a reduced incidence of bacterial HAIs and a decrease in the number of infectious episodes per patient.

Wohlfahrtiimonas chitiniclastica: current insights and complementary review from Chinese cases.

Wohlfahrtiimonas chitiniclastica is an emerging zoonotic pathogen associated with bacteremia, myiasis, and soft tissue infections. It is insufficiently identified and underestimated due to reasons, such as shortcomings of the traditional identification techniques and language barriers in local case reports from different regions. In this review, we summarize the currently available literature. In particular, we added previously overlooked cases from Chinese and other medical communities. The clinical characteristics, identification, and treatment of W. chitiniclastica are discussed. This work provides a complete review of the previous work including cases from human, animal, and other sources.

Role of Preoperative Multiple-Drug-Resistant Bacteria Intestinal Colonization in Cardiac Surgery: A Retrospective Study.

Background/Objectives: Multiple-drug-resistant (MDR) bacteria are pathogens resistant to three or more antibiotic classes, and infection with these bacteria is associated with increased mortality, morbidity, and hospital management costs. Given the rise in antibiotic resistance, selecting appropriate antimicrobial drugs and avoiding the unnecessary use of new antibiotics are crucial. Due to their nosocomial nature, monitoring and preventing MDR infections are essential. Methods: This study enrolled patients who underwent cardiac surgery from January 2020 to May 2022. The patients included were those 18 years or older who tested positive for MDR intestinal colonization before surgery. Excluded were patients who tested positive after surgery, or were younger than 18, pregnant, or lactating. For each positive patient, the National Surgical Quality Improvement Program (NSQIP) score was calculated. The data collected included age, gender, body mass index (BMI), the type of surgery, the intensive care unit (ICU) length of stay, ICU readmission, mortality, and other infections (pneumonia, bacteremia, or surgical site infection) to establish a control group and postoperative outcome measures. Results: No statistically significant differences were found between the groups regarding the ICU length of stay, new ICU admissions, or mortality. Additionally, there were no differences in the infection rates, such as bacteremia, wound infections, and pneumonia. Conclusions: Preoperative rectal colonization by MDR bacteria does not appear to worsen postoperative outcomes for cardiac surgery patients. These findings suggest that patients with a preoperative MDR-positive rectal sample might undergo cardiac surgery without significantly increased risk. Besides the limitations of this study, pre-surgical antibiotic prophylaxis may not need to be adjusted for patients with preoperative MDR positivity.

Ventriculoperitoneal shunt associated meningitis caused by Globicatella sanguinis: Review of an emerging human pathogen

The genus Globicatella has two species sanguinis and sulfidifaciens. Globicatella sanguinis is an unusual and rare pathogen causing bacteraemia, meningitis, and urinary tract infection in humans. The epidemiology and clinical significance of this pathogen remain largely unkown as Globicatella spp. are rarely isolated from clinical samples. We present a case of 36 year old male who had VP shunt associated meningitis caused by this pathogen. After the extensive literature search till date, we believe that this is the first case of VP shunt associated meningitis in a post trauma patient due to this pathogen. The identification of Globicatella sanguinis was made by Vitek 2 systems and was further confirmed by MALDI-TOF MS. Antibiotic Susceptibility Testing was performed by both Vitek 2 and Kirby bauer disc diffusion method according to CLSI standards for streptococcus spp. Its role as a human pathogen still remains only partially known because of the trouble involved in identification and the small number of reports pertaining to Globicatella. Furthermore, it has been demonstrated that Globicatella spp. are commensal organisms in humans which makes it even more difficult to eatablish it as a cause of disease.

Variability in invasive bacterial infection proportions among febrile infants aged 8-90 days using administrative data

ObjectiveDespite decades of research, knowledge is limited regarding sociodemographic risk factors (e.g., sex, rural/urban residence) for invasive bacterial infections (IBIs; bacteremia, bacterial meningitis) in young febrile infants and outcomes of current management strategies. Population-based administrative datasets can provide epidemiological insights not possible with clinical data but are limited because diagnosis codes alone may not accurately reflect culture-positive bacteremia or meningitis infections. Thus, using different IBI case definitions, we report IBI and missed IBI proportions in a population of febrile infants aged 8-90 days. MethodsFor this cross-sectional study, we used New York State’s all-payer database to identify healthy, full-term infants with fever aged 8-90 days evaluated in emergency departments from 2012-2023. We defined IBIs and missed IBIs using previously published diagnosis codes and then restricted original case definitions to inpatient encounters with variable lengths-of-stay. For each approach, we calculated total and age-stratified IBI and missed IBI proportions and used chi square statistics to compare proportions within and across age groups. ResultsOf 67,115 infants who met inclusion criteria (15,191 (23%) aged 8-28 days), total IBI and missed IBI proportions varied from 11.5-32.3/1,000 febrile infants and 4.2-8.0/100 IBIs, respectively. Although IBI proportions decreased significantly with advancing age, missed IBI proportions significantly increased. ConclusionsIBI and missed IBI proportions varied widely by case definition. Missed IBI proportions increased with advancing age in a step-wise fashion regardless of case definition. Validation studies are needed to compare IBI diagnosis codes with culture results to understand the accuracy of identifying IBIs with administrative data.

Identification of Glyoxalase A in Group B Streptococcus and its contribution to methylglyoxal tolerance and virulence.

Group B Streptococcus (GBS) is a Gram-positive pathobiont that commonly colonizes the gastrointestinal and lower female genital tracts but can cause sepsis and pneumonia in newborns and is a leading cause of neonatal meningitis. Despite the resulting disease severity, the pathogenesis of GBS is not completely understood, especially during the early phases of infection. To investigate GBS factors necessary for blood stream survival, we performed a transposon (Tn) mutant screen in our bacteremia infection model using a GBS mariner transposon mutant library previously developed by our group. We identified significantly underrepresented mutations in 539 genes that contribute to survival in the blood, including those encoding known virulence factors such as capsule, the β-hemolysin, and inorganic metal ion transport systems. Most of the underrepresented genes have not been previously characterized or studied in GBS, including gloA and gloB, which are homologs for genes involved in methylglyoxal (MG) detoxification. MG is a byproduct of glycolysis and a highly reactive toxic aldehyde that is elevated in immune cells during infection. Here, we observed MG sensitivity across multiple GBS isolates and confirm that gloA contributes to MG tolerance and invasive GBS infection. We show specifically that gloA contributes to GBS survival in the presence of neutrophils and depleting neutrophils in mice abrogates the decreased survival and infection of the gloA mutant. The requirement of the glyoxalase pathway during GBS infection suggests that MG detoxification is important for bacterial survival during host-pathogen interactions.

Single-cell Sequencing of Circulating Human Plasmablasts during Staphylococcus aureus Bacteremia.

Staphylococcus aureus is the major cause of healthcare-associated infections, including life-threatening conditions as bacteremia, endocarditis, and implant-associated infections. Despite adequate antibiotic treatment, the mortality of S. aureus bacteremia remains high. This calls for different strategies to treat this infection. In past years, sequencing of Ab repertoires from individuals previously exposed to a pathogen emerged as a successful method to discover novel therapeutic monoclonal Abs and understand circulating B cell diversity during infection. In this paper, we collected peripheral blood from 17 S. aureus bacteremia patients to study circulating plasmablast responses. Using single-cell transcriptome gene expression combined with sequencing of variable heavy and light Ig genes, we retrieved sequences from >400 plasmablasts revealing a high diversity with >300 unique variable heavy and light sequences. More than 200 variable sequences were synthesized to produce recombinant IgGs that were analyzed for binding to S. aureus whole bacterial cells. This revealed four novel monoclonal Abs that could specifically bind to the surface of S. aureus in the absence of Ig-binding surface SpA. Interestingly, three of four mAbs showed cross-reactivity with Staphylococcus epidermidis. Target identification revealed that the S. aureus-specific mAb BC153 targets wall teichoic acid, whereas cross-reactive mAbs BC019, BC020, and BC021 target lipoteichoic acid. All mAbs could induce Fc-dependent phagocytosis of staphylococci by human neutrophils. Altogether, we characterize the active B cell responses to S. aureus in infected patients and identify four functional mAbs against the S. aureus surface, of which three cross-react with S. epidermidis.

Pseudomonas aeruginosa Alkyl Quinolone Response is dampened by Enterococcus faecalis.

While we now appreciate that many infections are polymicrobial, we understand little of the specific actions between a given set of microbes to enable combinatorial survival and pathogenesis. The bacteria Pseudomonas aeruginosa and Enterococcus faecalis are both prevalent pathogens in wound, urinary tract, and bacteremic infections. While P. aeruginosa often kills other species in standard laboratory culture conditions, we present here that E. faecalis can be reliably co-cultured with P. aeruginosa. We specifically detail that ornithine produced by E. faecalis reduces the Pseudomonas Quinolone Signal response of P. aeruginosa . This reduction of the Pseudomonas Quinolone Signal response aids E. faecalis growth.

Antisalmonella Activities of Essential Oil of Psidium guajava Leaves: An In vitro and In vivo Study

Background: Life-threatening typhoidal salmonella infection is becoming more difficult to treat due to rising resistance to commonly used antibiotics. This resistance is aided by the biofilm-forming ability of the bacteria. This study investigated the in vitro and in vivo antisalmonella activities of essential oil of Psidium guajava leaves. Methods: Essential oil was extracted from the leaves of Psidium guajava with solvents. The sensitivity of Salmonella Typhi to the essential oil of Psidium guajava (EOPG) was assessed via the agar well diffusion method. Minimum inhibitory, bactericidal and biofilm-inhibitory concentrations (MIC, MBC and MBIC respectively) were measured using micro-broth dilution and crystal violet assay respectively. The effect of EOPG on the bacterial cell membrane was evaluated by measuring the efflux of potassium ions, inorganic phosphate and pyruvic acid. Bioautography and GC-MS were employed to identify the constituents of the active fraction of the EOPG. Effects of EOPG on the level of bacteremia and bone marrow infection in male Wistar rats were determined by plating caudal blood on salmonella-shigella agar. Selected serum cytokines were measured using ELISA kits. Effect on hepatic DNA was measured by comet assay while histological evaluation of the liver of infected rats was done by Hematoxylin and Eosin staining. Results: Essential oil of Psidium guajava leaves (EOPG) inhibited the growth of S. Typhi with a zone of inhibition of 13±0.2mm compared to 31±0.3mm recorded by ciprofloxacin. Minimum inhibitory, minimum bactericidal and minimum biofilm inhibitory concentrations were 25, >50 and 12.5 mg/mL respectively. Exposure to EOPG caused efflux of potassium ions, inorganic phosphate and pyruvic acid in S. Typhi. Oral administration of 50 mg/mL of EOPG reduced bacterial load in the blood and bone marrow of S. Typhi-infected rats significantly (P<0.05) when compared to untreated animals. Infection-induced reduction of serum IL-1β and rise in serum IFN-γ were ameliorated considerably in treated animals. The hepatic DNA of infected animals were protected from breakage in the group administered 50 mg/mL/day of EOPG compared with untreated, ciprofloxacin-treated as well as those administered 100 mg/mL/day of EOPG. Conclusion: EOPG has both in vitro and in vivo anti-salmonella activities, this could be exploited in developing new drug leads for treatment of typhoid fever

Predictive value of urine microscopy and urine culture in bacteraemic adults without localising urinary features.

Urine microscopy (UM) and urine culture (UC) are used in bacteraemic patients to identify a urinary focus of infection. However, their positive and negative predictive values (PPV and NPV) in patients without localising urinary features are uncertain. We aimed to determine the predictive value of UM/UC for diagnosing bacteraemic urinary tract infection (bUTI) in bacteraemic patients without localising urinary features. A retrospective study of bacteraemic adults was conducted. PPV and NPV of UM/UC for bacteraemic urinary tract infection (bUTI)was determined in two subgroups of patients without localising urinary features: those with an unclear focus of infection, and those with a suspected non-urinary focus of infection. In those with an unclear focus, univariate analysis for risk factors associated with bUTI was performed. A total of 871 patients were included. Localising urinary features were absent in 110 of 342 patients (32.2%) with bUTI. In patients with an unclear focus, UM had a PPV of 51.5% and an NPV of 96% for bUTI, and UC had a PPV of 75% and an NPV of 88.6%. In patients with a suspected non-urinary focus, UM had a PPV of 5.2% and an NPV of 100%, and UC had a PPV of 25% and an NPV of 99.5%. While some risk factors for bUTI in patients with an unclear focus were identified, 22 of 98 patients (22.4%)had bUTI despite no risk factors. bUTI without localising urinary features is common. In bacteraemia of unclear focus, UM/UC has a high NPV for excluding bUTI, although PPV is limited and non-urinary foci require consideration despite a positive result. UM/UC is low yield in those with a suspected non-urinary focus of infection.

The impact of the COVID-19 pandemic on pediatric bloodstream infections and alteration in antimicrobial resistance phenotypes in Gram-positive bacteria, 2020–2022

BackgroundAlteration in the etiology of pediatric bloodstream infections (BSIs) and antimicrobial resistance (AMR) is not well known during the Coronavirus disease 2019 (COVID-19) pandemic. This study aimed to investigate the impact of the COVID-19 pandemic on pediatric BSIs and alteration in antimicrobial resistance phenotypes in Gram-positive bacteria.MethodsThe frequency of BSIs among children under 18 years old was retrospectively recorded in a tertiary children’s hospital in Tehran, Iran from February 2020 to December 2022. The status of COVID-19 infection using reverse transcription polymerase chain reaction, bacteremia/fungemia according to BACTEC 9120 Culture System results, characterization of bacteria using biochemical tests, and antimicrobial susceptibility patterns for Gram-positive bacterial isolates using disk diffusion method were determined. Statistical analysis was done to measure the correlation of COVID-19 infection with BSIs and AMR.ResultsOut of 13,345 COVID-19 tests and 4,194 BACTEC blood culture requests, bacteremia/fungemia were confirmed in 10.37% (435/4,194) of the patients who requested both tests simultaneously. The COVID-19 infection was confirmed in 25.3% (110/435) of the patients with bacteremia/fungemia. The infection with characterized Gram-positive bacteria (GPB) and fungi was detected in 32.3% (140/433) and 8.31% (36/433) of the cases, respectively. Coagulase-negative Staphylococcus (CNS, 72, 16.62%), S. aureus (36, 8.3%), and Enterococcus spp. (22, 5%) were among the common isolates. Candida spp. and non-Candida yeasts were detected in 6.7% and 13.4% of the cases, respectively. A positive correlation was shown between the CNS bacteremia and COVID-19 infection (p-value = 0.019). Antibiotic susceptibility testing results showed the highest frequency of resistance to azithromycin among CNS, azithromycin and tetracycline among S. aureus and tetracycline among Enterococcus spp. Methicillin-resistance phenotype in the S. aureus (MRSA) and coagulase-negative Staphylococcus spp. (MR-CNS) was detected in 40% and 61.5% of the strains, respectively and the Enterococci were resistant to vancomycin in 33.3% of the isolates.ConclusionA decline in the trend of BSIs by GPB and an increase in AMR was shown in children during the COVID-19 pandemic. Increasing antibiotic resistance is a concern; however, chloramphenicol, linezolid, and vancomycin remain active against common causes of GPB-BSIs.

Damage-associated molecular patterns in bacteraemic infection, including a comparative analysis with bacterial DNA, a pathogen-associated molecular pattern

Damage-associated molecular patterns (DAMPs) and pathogen-associated molecular patterns (PAMPs) are key triggers of inflammation in sepsis. However, they have rarely been studied simultaneously. Thus, in the present study of patients with bacteraemic infection, we aimed to study how DAMP dynamics are linked to disease severity and outcome and to compare diagnostic and prognostic properties of a DAMP and a previously analysed PAMP (16S rDNA). In a prospective study of adult patients hospitalized with culture-proven community-onset bacteraemic infection, caused by Streptococcus pneumonia (n = 30), Staphylococcus aureus (n = 27), or Escherichia coli (n = 26), dynamics of a PAMP, i.e. 16S rDNA, have previously been presented. For the present study, blood samples obtained on hospital days 1–2 (when blood culture was positive), 3–4, 7 ± 1, 14 ± 2, and 28 ± 4 were analysed for four different DAMPs, i.e., nuclear DNA (nDNA), mitochondrial DNA (mtDNA), heat shock protein 90 alpha (HSP90α), and extracellular high mobility group box 1 (HMGB1). Sepsis was defined according to the Sepsis-3 criteria. The study outcomes were sepsis at admission and negative outcome, defined as intensive care unit (ICU) admission and/or death within 60 days. Of 83 study patients, sepsis was noted in 41 patients (49%) and a negative outcome was noted in 17 patients (20%). nDNA had areas under the receiver operating characteristic (ROC) curves of 0.78 for sepsis and 0.76 for negative outcome, which were higher than those of the other DAMPs and additional biomarkers (CRP, IL-6, IL-8, and IL-10). The nDNA and positive 16S rDNA results on day 1–2 were correlated with each other (r = 0.68, p < 0.001). Multivariate analyses showed that high day 1–2 concentrations of both nDNA and 16S rDNA were independently associated with sepsis. In addition, high day 1–2 concentration of nDNA was independently associated with negative outcomes. While 16S rDNA dissipated from the circulation within days, nDNA concentrations remained elevated throughout the follow-up period in patients with negative outcome. In conclusion, nDNA outperformed the other DAMPs regarding sepsis detection and outcome prediction. Both nDNA (a DAMP) and 16S rDNA (a PAMP) were independently linked to sepsis; nDNA was also associated with negative outcomes and persisted elevated in such cases. This highlights nDNA as an interesting marker within sepsis pathogenesis and as a promising clinical biomarker, warranting further studies.

Infective Endocarditis by Listeria Species—A Systematic Review

Infective endocarditis (IE) is a disease associated with significant morbidity and mortality. It is more commonly caused by Gram-positive cocci, but Gram-positive bacilli may seldom cause the disease. Listeria monocytogenes is an aerobic Gram-positive coccobacillus and a foodborne and opportunistic pathogen most commonly causing gastrointestinal infections, even though bacteremia, sepsis, meningitis, and fetal infections may also occur. Listeria IE has rarely been described, with most reports being case reports or case series. Thus, the characteristics of this disease remain largely unknown. This systematic review aimed to present all published Listeria IE studies and describe their characteristics. A search of PubMed, Scopus, and the Cochrane Library for studies providing information on epidemiology, clinical findings, treatment, and outcome of Listeria IE cases was performed. A total of 54 studies containing data from 62 patients were included. Among all patients, 64.5% were male; the median age was 69 years. Among all patients, 54.8% had a history of a prosthetic valve. The aortic valve was the most commonly affected, followed by the mitral. Fever, heart failure, and embolic phenomena were the most commonly encountered clinical findings. The only isolated species was L. monocytogenes. Antimicrobial resistance was relatively low for aminopenicillins and aminoglycosides, the most commonly used antimicrobials for treating L. monocytogenes IE. Surgery was performed in 27.4% of patients. Mortality was 37.1%. Patients who survived were more likely to have had a prosthetic valve, to have necessitated transesophageal echocardiography for the diagnosis, to have mitral valve IE, and to have had surgical management; however, no factor was identified in a multivariate logistic regression model as an independent factor for overall mortality.

Draft genome sequence of a spa non-typeable Staphylococcus aureus USA300 isolate causing complicated bacteremia.

Spa-typing is a major genetic tool used to distinguish between Staphylococcus aureus strains. Interestingly, although rare, ~1%-2 of isolates are considered Spa-non-typeable . Herein, we present the draft genome sequence of just such a strain, S. aureus TGH1097, a USA300 isolate from a complex bacteremia infection.

Development and validation of a predictive model for in-hospital mortality from perioperative bacteremia in gastrointestinal surgery.

Prognostic scores require fluctuating values, such as respiratory rate, which are unsuitable for retrospective auditing. Therefore, this study aimed to develop and validate a predictive model for in-hospital mortality associated with gastrointestinal surgery for retrospective auditing. Data from patients with bacteremia related to gastrointestinal surgery performed at Shizuoka General Hospital between July 2006 and December 2021 were extracted from a prospectively maintained database. Patients suspected of having a positive blood culture with contaminating bacteria or missing laboratory data were excluded. The remaining patients were randomly assigned in a 2:1 ratio to the deviation and validation cohorts. A logistic regression model estimated the odds ratios (ORs) and created a predictive model for in-hospital mortality. The model was evaluated using receiver operating characteristic (ROC) curves and calibration plots. Of 20,637 gastrointestinal surgeries, 398 resulted in bacteremia. The median age of patients with bacteremia was 72 years, and 66.1% were male. The most common pathogens were Staphylococcus (13.9%), followed by Bacteroides (12.4%) and Escherichia (11.4%). Multivariable logistic regression showed that creatinine abnormality (P < 0.001, OR = 3.39), decreased prognostic nutritional index (P < 0.001, OR = 0.90/unit), and age ≥ 75 years (P = 0.026, OR = 2.89) were independent prognostic factors for in-hospital mortality. The area under the ROC curve of the predictive model was 0.711 in the validation cohort. The calibration plot revealed that the model slightly overestimated mortality in the validation cohort. Using age, creatinine level, albumin level, and lymphocyte count, the model accurately predicted in-hospital mortality after bacteremia infection related to gastrointestinal surgery, demonstrating its suitability for retrospective audits.

Bacterial co-infections in cancer patients with COVID-19: predictors and antimicrobial resistance trends.

Within the context of the coronavirus disease 2019 (COVID-19) pandemic, this study investigated the multifaceted challenges of bacterial infections in cancer patients with COVID-19. It focuses on clinical predictors, resistance patterns, and microbiological characteristics. Over 18 months, 112 adult cancer patients with coronavirus infection confirmed by reverse transcription polymerase chain reaction (RT-PCR) were enrolled. Bloodstream and respiratory samples were evaluated for bacterial infection using the Phoenix automation system for definitive species identification. In vitro susceptibility testing followed the Clinical Laboratory Standards Institute (CLSI) M100-Ed30 guidelines. Bacterial infections affected 25.0% of patients, encompassing bacteremia (21.4%) and respiratory tract infections (8.0%). Multivariable analysis identified hypertension, age < 60, and critical COVID-19 as significant predictors for bacterial infections (p-values = 0.024, 0.029, and 0.039, respectively). Most patients received antimicrobial therapy (93.8%), including last-resort carbapenems (52.7%) and colistin (8.9%). Thirty-three bacterial isolates were identified, with secondary infections doubling co-infection rates. Escherichia coli, Klebsiella species, and Staphylococcus aureus were the most common co-infecting species, while Klebsiella, Acinetobacter, and Pseudomonas species were more frequently associated with secondary infections. Alarmingly, 84.8% of isolates displayed high resistance patterns. All isolated S. aureus species were methicillin-resistant, and 62.5% of Gram-negative bacteria were exclusively sensitive to colistin. The dominance of highly transmissible hospital-acquired bacterial species, with increased resistance and extensive antibiotic use in COVID-19 patients, necessitates strict infection control and antimicrobial stewardship. Developing customized antimicrobial strategies for cancer patients with COVID-19 is crucial to managing bacterial infections effectively and improving patient outcomes.