Concomitant Bacteremia Research Articles

Monotherapy versus combination for the treatment of Stenotrophomonas maltophilia: a multicenter cohort study

ABSTRACT Background The aim of this study was to compare the safety and effectiveness of monotherapy versus combination therapy for the treatment of infections caused by S. maltophilia. Methods This retrospective, multicenter, cohort study included patients treated with either monotherapy or combination therapy for infections caused by S. maltophilia. Primary outcomes included overall in-hospital mortality, 30-day mortality, and clinical cure. Safety outcomes were also evaluated. Multivariable logistic regression was used as a control for confounding variables. Results A total of 407 patients were included, 330 patients received monotherapy and 77 patients received combination therapy. A total of 21% presented with concomitant bacteremia. After adjusting the differences between the two groups, there were no statistically significant differences between patients who received monotherapy versus combination therapy in clinical cure (55% vs 65%; OR, 0.72; 95% CI, 0.40–1.31) and overall in-hospital mortality (52% vs 49%; OR, 0.84; 95% CI, 0.45–1.57). However, patients who received monotherapy had a lower rate of 30-day mortality (28% vs 32%; OR, 0.45; 95% CI, 0.22–0.90) and acute kidney injury (9% vs 18%; OR, 0.35; 95% CI, 0.16–0.78). Conclusion Clinical outcomes did not significantly differ in patients who received combination therapy versus monotherapy. More data are needed to validate these findings.

Time to positivity of Klebsiella pneumoniae in blood cultures as prognostic marker in patients with intra-abdominal infection: A retrospective study

ABSTRACT Klebsiella pneumoniae is a common causative pathogen of intra-abdominal infection with concomitant bacteraemia, leading to a significant mortality risk. The time to positivity (TTP) of blood culture is postulated to be a prognostic factor in bacteraemia caused by other species. Therefore, this study aimed to investigate the prognostic value of TTP in these patients. The single-centred, retrospective, observational cohort study was conducted between 1 July 2016 and 30 June 2021. All adult emergency department patients with diagnosis of intra-abdominal infection and underwent blood culture collection which yield K. pneumoniae during this period were enrolled. A total of 196 patients were included in the study. The overall 30-day mortality rate was 12.2% (24/196), and the median TTP of the studied cohort was 12.3 h (10.5–15.8 h). TTP revealed a moderate 30-day mortality discriminative ability (area under the curve 0.73, p < 0.001). Compared with the late TTP group (>12 h, N = 109), patients in the early TTP (≤12 h, N = 87) group had a significantly higher risk of 30-day morality (21.8% vs. 4.6%, p < 0.01) and other adverse outcomes. Furthermore, TTP (odds ratio [OR] = 0.79, p = 0.02), Pitt bacteraemia score (OR = 1.30, p = 0.03), and implementation of source control (OR = 0.06, p < 0.01) were identified as independent factors related to 30-day mortality risk in patients with intra-abdominal infection and K. pneumoniae bacteraemia. Therefore, physicians can use TTP for prognosis stratification in these patients.

Ceftaroline fosamil – fifth-generation cephalosporin with anti-MRSA activity in the treatment of severe infections in pediatric practice

Сeftaroline fosamil is a fifth-generation cephalosporin and a unique β-lactam and the only currently registered in the Russian Federation cephalosporin with activity against MRSA. Сeftaroline is approved for use in pediatric practice for the treatment of children with community-acquired pneumonia and complicated skin and soft tissue infections, including cases of patients with concomitant bacteremia. The place of ceftaroline in the treatment of severe and life-threatening infections in children is primarily due to its high activity against the key causative agents of community-acquired pneumonia and skin and soft tissue infections (first of all, S. pneumoniae and S. aureus, including MRSA), bactericidal mechanism of action, creation of effective concentrations and penetration into the infection’s site, low potential for resistance development, proven significant development of clinical effect, high clinical efficacy in these infections and favorable tolerability and safety profile. The review presents the results of the program of clinical evaluation of ceftaroline in children, analyzes current data on etiology and antimicrobial resistance of the key pathogens of community-acquired pneumonia and skin and soft tissue infections in the Russian Federation, defines the place of ceftaroline in clinical recommendations in children, and characterizes the patient’s profile to whom the prescription of ceftaroline in hospital is indicated.

Invasive Candidiasis in Adult Patients with COVID-19: Results of a Multicenter Study in St. Petersburg, Russia.

We studied the risk factors, etiology, clinical manifestations, and treatment outcomes of COVID-19-associated invasive candidiasis (COVID-IC) in adult patients admitted to six medical facilities in St. Petersburg. (November 2020-December 2022). In this retrospective study, we included 72 patients with COVID-IC with a median age of 61 years (range 29-96), 51% of whom were women. The predisposing factors for COVID-IC were a central venous catheter (CVC) for more than 10 days (the odds ratio (OR) = 70 [15-309]), abdominal surgical treatment performed in the previous 2 weeks (OR = 8.8 [1.9-40.3]), bacteremia (OR = 10.6 [4.8-23.3]), pulmonary ventilation (OR = 12.9 [5.9-28.4]), and hemodialysis (OR = 11.5 [2.5-50.8]). The signs and symptoms of COVID-IC were non-specific: fever (59%), renal failure (33%), liver failure (23%), and cardiovascular failure (10%). Candida albicans (41%) predominated among the pathogens of the candidemia. The multidrug-resistant Candida species C. auris (23%) and C. glabrata (5%) were also identified. Empirical therapy was used in 21% of COVID-IC patients: azole-93%, echinocandin-7%. The majority of COVID-IC patients (79%) received, after laboratory confirmation of the diagnosis of IC, fluconazole (47%), voriconazole (25%), echinocandin (26%), and amphotericin B (2)%. The 30 days overall survival rate was 45%. The prognosis worsened concomitant bacteremia, hemodialysis, and long-term therapy by systemic glucocorticosteroids (SGCs), bronchial colonization with Candida spp. The survival prognosis was improved by the early change/replacement of CVC (within 24 h), the initiation of empirical therapy, and the use of echinocandin. Conclusions: We highlighted the risk factors that predispose COVID-19 patients to candidiasis and worsen the survival prognosis. Their individual effects in patients with COVID-19 must be well understood to prevent the development of opportunistic co-infections that drastically lower chances of survival.

Bacteremia and antimicrobial resistance pattern of uropathogens causing febrile urinary tract infection in a Pediatric University Hospital.

Febrile urinary tract infections (UTIs) in children are among the most serious bacterial infections. Inadequate treatment can lead to kidney scarring and permanent kidney damage. Eight to ten percent of children with UTIs could have concomitant bacteremia. The study aimed to estimate the prevalence of UTI-associated bacteremia and identify common organisms causing UTIs and their antimicrobial susceptibility patterns to help guide empiric antimicrobial therapy. The current study was conducted over a 6-month period on children admitted with febrile UTIs at Alexandria University Children's Hospital. Blood and urine samples were collected for culture and antimicrobial susceptibility. A total of 103 children with a median age of 12 months (IQR 6.0-24.0) were included in the study. Concomitant bacteremia was present in 63.1% (n=65). The median temperature of 38.40°C (IQR 38.15-38.60) and the median creatinine level of 0.18 mg/dL (IQR 0.14-0.25) were significantly higher in the bacteremic group compared to the non-bacteremic group (p=0.005, p=0.034, respectively). E. coli (n=51; 49.5%) and Klebsiella pneumoniae (n=30; 29.1%) were the most common isolated organisms. Most (n=68; 66%) of the isolated organisms were multidrug-resistant (MDR), followed by extensively drug-resistant (XDR) (n=16; 15.5%), and pan-drug-resistant (PDR) organisms (n=1; 1%). E. coli showed lower resistance to gentamicin and ceftriaxone (9.8 % and 13.7%, respectively). E. coli remains the most important UTI pathogen. Ceftriaxone and gentamicin are good empiric options for febrile UTIs in our hospital.

Clinical relevance of blood urea nitrogen to serum albumin ratio for predicting bacteremia in very young children with febrile urinary tract infection.

Urinary tract infections (UTIs) are one of the most common bacterial infections in febrile children and a common cause of hospitalization, especially in very young children. We examined the clinical characteristics and predictive factors of concomitant bacteremia in pediatric patients with febrile UTI aged ≤24 months. This retrospective multicenter study reviewed medical data from 2,141 patients from three centers from January 2000 to December 2019. Enrolled cases were classified into the bacteremic UTI and non-bacteremic UTI groups according to the presence of blood culture pathogens. Among 2,141 patients with febrile UTI, 40 (1.9%) had concomitant bacteremia. All patients in the bacterial group were aged ≤6 months. Multivariate analysis revealed that younger age, lower blood lymphocyte counts and serum albumin levels, higher C-reactive protein (CRP) levels, blood urea nitrogen (BUN) levels, and BUN/serum albumin ratio were independent risk factors of concomitant bacteremia. The area under the receiver-operating characteristic curves predicting bacteremia were 0.668 for CRP, 0.673 for lymphocytes, and 0.759 for the BUN/albumin ratio. The present study identified the BUN/albumin ratio and lower blood lymphocyte counts as novel predictive factors for bacteremia in young infants with febrile UTI in addition to the previously identified factors of younger age and higher CRP levels. Our findings could help to identify patients at high risk of bacteremia and benefit decision-making in the management of infants with febrile UTI.

Clinical characteristics and outcomes in febrile infants aged 29-90 days with urinary tract infections and cerebrospinal fluid pleocytosis.

Fever without a focus is a common reason for medical evaluations, hospitalizations, and the antimicrobial treatment of infants younger than 90 days. The presence of cerebrospinal fluid (CSF) pleocytosis could be challenge for clinicians who treat febrile young infants with urinary tract infection (UTI). We evaluated the factors associated with sterile CSF pleocytosis and the clinical outcomes of the patients. A retrospective review of patients aged 29-90 days with febrile UTIs who underwent a non-traumatic lumbar puncture (LP) at Pusan National University Hospital from January 2010 to December 2020 was conducted. CSF pleocytosis was defined as white blood cell (WBC) counts ≥9/mm3. A total of 156 patients with UTI were eligible for this study. Four (2.6%) had concomitant bacteremia. However, no patients had culture-proven bacterial meningitis. In correlation analysis, although weak strength, CSF WBC counts were positively correlated with C-reactive protein (CRP) level (Spearman r = 0.234; P = 0.003). Thirty-three patients had CSF pleocytosis [21.2%; 95% confidential interval (CI), 15.5-28.2]. The time from fever onset to the hospital visit, peripheral blood platelet counts, and CRP level at admission were statistically significant in patients with sterile CSF pleocytosis compared to those without CSF pleocytosis. In the multiple logistic regression, only CRP was independently associated with sterile CSF pleocytosis (cutoff, 3.425 mg/dl; adjusted odds ratio, 2.77; 95% CI, 1.19-6.88). The proportion of fever defervescence by hospital day 2 was 87.9% in patients with CSF pleocytosis and 89.4% in those without CSF pleocytosis (P = 0.759). There was no statistical difference in the fever defervescence curves between the two patient groups (P = 0.567). No patients had neurological manifestations or complications. Coexisting sterile CSF pleocytosis among febrile infants with UTIs suggest a systemic inflammatory response. However, the clinical outcomes between the two groups were similar. A selective LP should be considered in young infants with evidence of UTI, and inappropriate antibiotic therapy for sterile CSF pleocytosis should be avoided.

An unusual case of orbital abscess due to Morganella morganii and Klebsiella pneumoniae, following acute on chronic dacryocystitis

Orbital abscess secondary to dacryocystitis is rare.[1] Morganella morganii is a gram-negative rod and a facultative anaerobic enteric bacterium causing opportunistic infection, often isolated as a cause of nosocomial infection, specifically in urinary tract or wound infections. Risk factors may be old age, presence of concomitant bacteremia, hospitalization, recent surgery, concurrent antibiotic use, and immunocompromised hosts.[2] According to authors' knowledge, till date, only one case of orbital abscess due to M. morganii has been reported secondary to sinusitis. There are no reports of orbital abscess due to M. morganii following dacryocystitis till date.[3] We report a rare case of orbital abscess secondary to dacrocystitis caused by M. morganii and Klebsiella pneumoniae in an immunocompetent patient.

Prevalence of Concomitant Bacteria among malaria Patients attending Government Hospitals in Ondo State, South-West Nigeria

Background:Patients suffering from severe malaria have an increased risk of co-occurring bacterial sepsis, which results in higher mortality rates than malaria alone. Concomitant bacterial infections can worsen malaria symptoms, leading to increased illness and death rates. This study aimed to investigate the relationship between malaria and concomitant bacteremia among patients in Ondo State, Nigeria.Aim: The study's objective was to determine the prevalence of bacterial concomitant among malaria patients and assess the relationship between malaria and bacteremia in the study population.Material and Methods: A cross-sectional study was conducted among feverish individuals in certain Ondo State government hospitals. One milliliter of blood was collected from malaria-positive patients, confirmed using microscopic examination of Giemsa-stained thick and thin blood films, and an Malaria rapid diagnostic tests (RDT) kit was cultured for bacterial enumeration. The collected data were statistically analyzed using Chi-square and correlation tests, with a 𝑃value &lt;0.05 considered significant.Result: The study found a concomitant bacteria prevalence of 19.95% (85/426), with a significant (P= &lt;0.001, r = 0.00334) positive correlation between malaria and bacterial concomitant.Age was significantly (p = 0.072, df= 18, χ2 = 27.389) associated with bacterial concomitant, and the mean bacterial count was 9.71±1.481 cfu/ml x 107. Furthermore, level of education, marital status and tribe also significantly (p&lt;0.05) contributed to the prevalence of concomitant bacteria.Conclusion: Our research concludes that malaria may increase the risk of bacteremia, and a significant association between malaria and concomitant bacterial infection exists. However, the reasons for bacteria's abilityto invade and thrive in the bloodstream vary. The study's findings suggest that interventions are needed to address the high prevalence of concomitant bacterial infections among malaria patients in the study area.

Post-COVID-19 Pneumocystis pneumonia cases from Pakistan: an observational study.

Background. Concurrent coronavirus disease 2019 (COVID-19) and Pneumocystis jirovecii pneumonia (PJP) has been described in various reports, with a recent study describing a 9.3 % P. jirovecii detection rate in critically ill COVID-19 patients. Methods. Patients with PCR-confirmed PJP following COVID-19 infection who were admitted to Aga Khan University Hospital, Karachi, Pakistan from March 2020-June 2021 were identified through a laboratory database. Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus was performed by RT-PCR Cobas SARS-CoV-2 qualitative assay. P. jirovecii PCR was performed using the RealStar Pneumocystis jirovecii PCR kit. Clinical, radiological and laboratory data for PJP patients were recorded. Results. During the study period, 3707 patients were admitted with COVID-19 at our hospital. P. jirovecii PCR was requested for 90 patients and was positive in 10 (11 %). Five out of 10 patients were discharged from the hospital and later developed cough and dyspnoea. Five patients remained hospitalized with severe COVID-19 and developed PJP. Eight patients in our study received systemic steroids. The trends of lymphocyte counts of all patients showed a lymphocyte count of <1000 mm-3 (<1.0×106 cells µl-1) in the week of PJP diagnosis. Four patients did not survive; one of these patients did not receive co-trimoxazole due to late diagnosis, one patient had concomitant nosocomial pneumonia and bacteraemia with multidrug-resistant Acinetobacter species, and two patients had concomitant aspergillosis. Conclusion. In summary, invasive fungal infections such as PJP should be considered as a complication in COVID-19 patients, with prompt evaluation and management.

Procalcitonin as a Predictor of Septic Knee Arthritis: A Retrospective Cohort Study.

Differentiating septic arthritis from aseptic arthritis (AA) of the knee is difficult without arthrocentesis. Although procalcitonin (PCT) has shown diagnostic value in identifying bacterial infections, it has not been established as a reliable marker for identifying septic arthritis (SA). Recent studies have shown promise in the use of PCT as a useful systemic marker for identifying septic arthritis versus AA. This observational retrospective review compares PCT with routine inflammatory markers as a tool for differentiating septic arthritis versus AA in patients with acute, atraumatic knee pain. Fifty-three consecutive patients (24 SA, 29 AA) were retrospectively reviewed at one institution with concern for SA. SA was diagnosed based on a physical examination, laboratory markers, and arthrocentesis. Laboratory indices were compared between the septic arthritis and AA groups. Data analysis was conducted to define sensitivity and specificity. Receiver operator characteristic curve analysis and regression were conducted to determine the best marker for acute SA of the knee. Using multiple logistic regression, bacteremia (OR 6.75 ± 5.75) was determined to be the greatest predictor of SA. On linear regression, concomitant bacteremia (coef 3.07 ± 0.87), SA (coef 2.18 ± 0.70), and the presence of pseudogout crystals (coef 1.80 ± 0.83) on microscopy predicted an increase in PCT. Using a PCT cutoff of 0.25 ng/mL yields a sensitivity of 91.7% and specificity of 55.2% for predicting SA; however, the ideal cutoff in our series was 0.32 ng/mL with a sensitivity of 79.2% and specificity of 72.4%. PCT was superior to the white blood cell count, erythrocyte sedimentation rate, and C-reactive protein in the area under the receiver-operating characteristic curve analysis. Procalcitonin seems to be the most sensitive and specific systemic marker in differentiating septic from AA.

674. Successful Management of ESBL Infections in Physician Outpatient Infusion Centers (POICs)

Abstract Background Infections with extended-spectrum β-lactamase (ESBL)-producing pathogens present treatment challenges with higher costs of care. Hospitalized patients (pts) with ESBL infections often require outpatient antimicrobial therapy (OPAT) following discharge. An Infectious Disease (ID) physician can facilitate optimal management in both the inpatient and outpatient setting, particularly when a POIC is an option. The increase of ESBL incidence led us to evaluate management and outcomes of genitourinary (GU) and intra-abdominal infections (IAI), the top two ESBL diagnoses treated in POICs. Methods Records were queried for pts hospitalized with ESBL infection and discharged to a POIC between 2019 and 2020. Primary outcome was completion of OPAT. Non-successful completion was defined as premature discontinuation of OPAT including hospital readmission. Adverse events (AEs) and re-treatment within 30 days were captured. Results A total of 112 pts (mean age: 59±17 years, 50% female) from 14 POICs were identified (93 GU, 19 IAI). Of these, 51% had their first ESBL infection and 52% were community-acquired prior to hospitalization. A total of 38% presented with concomitant bacteremia. ESBL E. coli was the predominant Gram-negative pathogen in both infection types (Table 1). Mean hospital LOS was 6±4 days (5±2 days GU, 11±6 days IAI) followed by 13±9 days of OPAT (12±7 days GU, 16±11 days IAI). Carbapenems were most frequently used as treatment (89% ertapenem, 7% meropenem). Overall, 106 pts (95%) successfully completed OPAT. Six pts (5%) discontinued due to hospital readmission. AEs were reported in 15 pts (13%), the majority of which were mild. Re-treatment in the POIC within 30 days post OPAT completion occurred in 6 GU pts. None were lost to follow-up. Table 1 summarizes primary outcome by clinical characteristics. Both GU and IAI pts had 95% successful OPAT completion. Table 1.Successful and non-successful completion of OPAT in patients with ESBL infections Conclusion Outpatient treatment of ESBL infections in POICs post-hospitalization showed high completion rates with low occurrence of readmissions and re-treatments. Consistent with a rise in ESBL infections, our incidence of community-acquired ESBL infections prior to hospitalization were high at 52%. Once ESBL infections were identified in the hospital, the ID physicians with a POIC rapidly facilitated discharge to OPAT. Disclosures Ramesh V. Nathan, MD, FIDSA, Eli Lilly &amp; Co.: Grant/Research Support Brian S. Metzger, MD, MPH, AbbVie: Advisor/Consultant|Cumberland: Advisor/Consultant Lucinda J. Van Anglen, PharmD, Merck &amp; Co.: Grant/Research Support|Paratek: Grant/Research Support.

1828. Dalbavancin Utilization and Associated Clinical Outcomes: A Case-Series

Abstract Background Dalbavancin is an intravenous (IV) long acting lipoglycopeptide approved for use in acute bacterial skin and skin structure infections (ABSSSI). However, given the prolonged half-life, there is interest in using this agent as an alternative therapy for patients unable or unwilling to comply with conventional IV therapy. These include off-label treatment of deeper-seated infections such as infective endocarditis or osteomyelitis. This case series assesses the efficacy and safety of dalbavancin and its role as an alternative therapy in serious gram-positive infections. Methods Retrospective case series of hospitalized adult patients who received at least one dose of dalbavancin at one of the eight hospitals within the Providence Oregon health system between December 2019 through January 2022. Eligible patients had appropriate follow-up within the 90-day period after the last dose was given. Patients who received dalbavancin as empiric therapy or had a vancomycin-resistant isolate were excluded. Clinical cure was defined as no clinical, laboratory, or microbiological evidence of persistent or recurring infection during the 90-day follow-up period. Results 110 patients were included in this analysis; 41% were IV drug (IVDU) users. The average age was 50.5 years, and the most common organism was Methicillin-sensitive Staphylococcus aureus (48.2%). Bacteremia occurred in 50% of the cases, and the most common infection site was osteomyelitis or native joint infections (31.8%). 30-day all-cause readmission, recurrence, and mortality occurred in 12.7% (2/110), 1.8% (14/110), and 0%, respectively. 30 to 90-day all-cause readmission, recurrence, and mortality occurred in 14.5% (16/110), 7.3% (8/110), and 1.8% (2/110), respectively. Adverse events occurred in 4.5% (5/110) of the cases, where infusion related reactions were most common. Presumed clinical cure occurred in 89% (98/110). Conclusion A high percentage of patients in this case series were bacteremic, which differs from prior reports. Overall, dalbavancin appears to be a safe and effective treatment alternative for deeper-seated infections, including those with concomitant bacteremia. Disclosures All Authors: No reported disclosures.

2231. Assessing Clinical Cure of Empiric Piperacillin-Tazobactam for ESBL Urinary Tract Infections (ACCEPT-UTI)

Abstract Background While literature supports use of carbapenems over piperacillin-tazobactam (TZP) for extended spectrum beta-lactamase (ESBL) bacteremia, data is limited regarding the use of TZP for ESBL urinary tract infections (UTIs). The objective of this study is to determine if patients have similar clinical outcomes when empirically treated with TZP versus carbapenems for ESBL UTIs. Methods This IRB-approved, retrospective, non-inferiority study evaluated adult patients admitted to a 5-facility healthcare system from January 1, 2016 to June 30, 2021. Patients who received a carbapenem or TZP empirically for at least 48 hours with a urine culture positive for an ESBL, urinary symptoms or leukocytosis, and isolate susceptibility to the empiric antibiotic of choice were included. The primary outcome was clinical success within 48 hours defined as resolution of temperature (36-38 °C), resolution of symptoms or leukocytosis (WBC &amp;lt; 12 x103/μL) in the absence of symptoms, and the absence of readmission for an ESBL UTI within 6 months. Secondary outcomes included time to clinical success, hospital length of stay (LOS), and 30-day all-cause mortality. Results A total of 223 patients were included with 123 (55%) patients receiving TZP and 100 (45%) patients receiving a carbapenem. Patients were predominantly female (65%) and Caucasian (52%) with a median (IQR) age of 70 (58, 81) years. Baseline characteristics were similar between the groups with no difference in complicated cystitis (60%), pyelonephritis (27%), or concomitant bacteremia (25%) (Table 1). There was no difference in the primary outcome of clinical success between the carbapenem and TZP group (60% vs 59%, respectively; p=0.92). Additionally, there was no difference in median (IQR) time to clinical success [39 (21, 52) vs 40 (25, 57) hrs, p=0.53], median hospital LOS [7.0 (5.1, 10.6) vs 6.8 (4.7, 9.2) days, p=0.12], or 30-day all-cause mortality (4% vs 2%, p=0.72) between the carbapenem and TZP groups, respectively (Table 2). Conclusion In this large, multi-center study, we found no difference in clinical outcomes in patients with UTIs caused by ESBL-producing organisms treated empirically with TZP versus carbapenems. Clinicians could consider using TZP in patients with ESBL UTIs susceptible to TZP. Disclosures Michael S. Gelfand, MD, AbbVie: Expert Testimony|La Jolla: Expert Testimony Kerry O. Cleveland, MD, AbbVie: Honoraria|Cumberland: Honoraria|Merck: Honoraria|Pfizer: Honoraria.

Comparison of the Clinical and Genotypic Characteristics of Uropathogenic Escherichia coli Strains According to Sex in Korea.

In this study, we compared the microbiological, genotypic, and antibiotic resistance characteristics of uropathogenic Escherichia coli (UPEC) strains in patients with pyelonephritis in Korea according to sex based on data corresponding to the February 2015 to June 2018 period. Based on Escherichia coli phylogenetic group analysis, gene virulence detection, and subgroup analyses by sex, we observed that the antibiotic resistance percentages and proportions corresponding to extended-spectrum beta-lactamase producing UPEC were higher in males than in females. In addition, phylogenetic group B2 showed predominance in both the male and female groups, which further showed similar adhesion molecule distributions. Toxin-associated factors, hlyA and cnf1, were more common in males. In clinical presentations, urinary predisposing factors, complicated urinary tract infections (UTIs), concomitant bacteremia, and persistent fever were also more common with males. Although females and males showed UPEC genotypic differences, there were no differences between them with respect to poor outcomes. Persistent fever was associated with community-acquired infection and bacteremic UTI and relapsed UTI within 3 months was associated with urinary tract stone. In future, it will be necessary to conduct multicenter studies, involving more cases on UPEC to validate our results.

ANTIBIOTIC RESISTANCE AND PLASMID ANALYSIS OF BACTERIA ISOLATED FROM CHILDREN WITH BACTEREMIA AND MALARIA IN EKITI STATE

Increased resistance of bacteria isolated from children with bacteremia and malaria has being reported to be due to lack of laboratory investigations before antibiotics are prescribed alongside antimalaria. Therefore this study was carried out to determine the rate of resistance of bacteria isolated from children with bacteremia and malaria. A total of 34 bacteria strains belonging to 4 genera were isolated out of which 44.1% were E. coli, 29.4% were Staphylococcus aureus, 17.7% were Pseudomonas aeruginosa and 8.8% were Salmonella typhi. Fourteen (7.5%) of the children had concomitant bacteremia and malaria, Thirty seven (19.9%) had malaria only while 20 (10.8%) had bacteremia only. Twelve (80%) of the isolated E.coli exhibited the highest resistance to augmentin while 6(60%) of the staph aureus exhibited the highest resistance to augmentin and ceftriaxone. Two (66.6%) of the salmonella typhi showed the highest resistance to ampicillin and ceftriaxone, while 3(50%) of the pseudomonas exhibited the highest resistance to gentamicine. The plasmid analysis of the selected antibiotic resistance bacteria shows that there are detectable plasmid in 3(37.5%) of the isolates. The post curing of the isolates containing plasmid shows that the resistance in E.coli was not plasmid mediated while the resistance in Staphylococcus aureus was plasmid mediated. In conclusion the result shows that the rate of antibiotic resistance is high among the children examined and it is not all the children who have malaria that also have bacteremia, therefore a proper laboratory test should be carried out before antibiotics is accompanied by antimalaria.

Mesenchymal-Stem-Cell-Derived Extracellular Vesicles Attenuate Brain Injury in Escherichia coli Meningitis in Newborn Rats.

We recently reported that transplantation of mesenchymal stem cells (MSCs) significantly reduced bacterial growth and brain injury in neonatal meningitis induced by Escherichia coli (E. coli) infection in newborn rats. As a next step, to verify whether the MSCs protect against brain injury in a paracrine manner, this study was designed to estimate the efficacy of MSC-derived extracellular vesicles (MSC-EVs) in E. coli meningitis in newborn rats. E. coli meningitis was induced without concomitant bacteremia by the intra-cerebroventricular injection of 5 × 102 colony-forming units of K1 (-) E. coli in rats, at postnatal day 11. MSC-EVs were intra-cerebroventricularly transplanted 6 h after the induction of meningitis, and antibiotics were administered for three consecutive days starting at 24 h after the induction of meningitis. The increase in bacterial growth in the cerebrospinal fluid measured at 24 h after the meningitis induction was not significantly reduced following MSC-EV transplantation. However, an increase in brain cell death, reactive gliosis, and inflammation following meningitis were significantly attenuated after MSC-EV transplantation. Taken together, our results indicate that MSCs show anti-apoptotic, anti-gliosis, and anti-inflammatory, but not antibacterial effects, in an EV-mediated paracrine manner in E. coli-induced neonatal meningitis.

Machine-learning based prediction and analysis of prognostic risk factors in patients with candidemia and bacteraemia: a 5-year analysis.

Bacteraemia has attracted great attention owing to its serious outcomes, including deterioration of the primary disease, infection, severe sepsis, overwhelming septic shock or even death. Candidemia, secondary to bacteraemia, is frequently seen in hospitalised patients, especially in those with weak immune systems, and may lead to lethal outcomes and a poor prognosis. Moreover, higher morbidity and mortality associated with candidemia. Owing to the complexity of patient conditions, the occurrence of candidemia is increasing. Candidemia-related studies are relatively challenging. Because candidemia is associated with increasing mortality related to invasive infection of organs, its pathogenesis warrants further investigation. We collected the relevant clinical data of 367 patients with concomitant candidemia and bacteraemia in the first hospital of China Medical University from January 2013 to January 2018. We analysed the available information and attempted to obtain the undisclosed information. Subsequently, we used machine learning to screen for regulators such as prognostic factors related to death. Of the 367 patients, 231 (62.9%) were men, and the median age of all patients was 61 years old (range, 52–71 years), with 133 (36.2%) patients aged >65 years. In addition, 249 patients had hypoproteinaemia, and 169 patients were admitted to the intensive care unit (ICU) during hospitalisation. The most common fungi and bacteria associated with tumour development and Candida infection were Candida parapsilosis and Acinetobacter baumannii, respectively. We used machine learning to screen for death-related prognostic factors in patients with candidemia and bacteraemia mainly based on integrated information. The results showed that serum creatinine level, endotoxic shock, length of stay in ICU, age, leukocyte count, total parenteral nutrition, total bilirubin level, length of stay in the hospital, PCT level and lymphocyte count were identified as the main prognostic factors. These findings will greatly help clinicians treat patients with candidemia and bacteraemia.

Intravenous to oral antibiotics versus intravenous antibiotics: a step-up or a step-down for extended spectrum β-lactamase (ESBL)-producing urinary tract infections without concomitant bacteraemia?

The Infectious Diseases Society of America (IDSA) recommends numerous antibiotics for the treatment of urinary tract infections (UTIs) caused by extended-spectrum β-lactamase (ESBL)-producing bacteria. The purpose of this study was to evaluate clinical outcomes of oral step-down antibiotics compared with continued intravenous therapy in UTIs without bacteraemia. This multicentre, retrospective, cohort study was conducted in hospitalised patients with ESBL-producing UTIs between July 2016 and March 2020. The primary outcome was a composite all-cause clinical failure, defined as 30-day re-admission, 30-day hospital mortality or a change in oral antibiotics during hospitalisation. Secondary outcomes included individual primary outcome components, re-admission due to a recurrent UTI, change in antibiotic during hospitalisation, hospital length of stay (LOS), antibiotic costs and adverse events. The study included 153 patients. The primary outcome occurred in 28% of both groups (27/95 vs. 16/58; P=0.91). The primary outcome components were similar: re-admission (26% vs. 26%; P=0.95); hospital mortality (2% vs. 2%; P=1.0); and change in antibiotics (0% vs. 2%; P=0.38). Mean hospital LOS and direct antibiotic costs were 8 ± 6 days vs. 5 ± 2 days (P < 0.01) and US$278 ± 244 vs. US$180 ± 104 (P < 0.01), respectively. Adverse events were similar, except diarrhoea (15% vs. 2%; P=0.01). There was no difference in clinical failure, re-admission rate, re-admission due to a recurrent UTI, mortality rate or antibiotic change between groups. The switch group was associated with reduced hospital LOS and inpatient antibiotic costs.

88. Effect of an MDR Enterobacterales Screening Tool on Antibiotic Prescribing for Abdominal Infections Caused by Mixed Bacteria

Abstract Background Background: Choosing antibiotics for infections caused by mixed Enterobacterales is challenging. Our microbiology lab implemented a multi-drug resistance (MDR) screen for cultures with mixed gram-negative to direct clinicians to use 3rd generation cephalosporins for screen neg. pathogens, and to use broader beta-lactams for screen-pos. pathogens. Here we report the effect of MDR screen on final antibiotic choice. Methods Methods: We retrospectively reviewed cases with abdominal infections caused by mixed bacteria at UNC Medical Center between August and November 2020. Cultures with non-Enterobacteraeles gram negatives were excluded. MDR screen was done by plating mixed Enterobacterales on HardyCHROM™ ESBL agar. Screen-pos. cases were updated “MDR Enterobacterales present” and pathogens were identified with full susceptibilities. Screen-neg. cases were labeled “MDR Enterobacterales not present”. Definitely covering antibiotics were defined by the use of 3rd generation cephalosporins for screen neg. cases, or based on susceptibilities in case of screen pos. organisms or concomitant bacteremia. Possibly covering antibiotics included regimens whose susceptibility could not be predicted based on the screen (e.g., amox/clav or quinolone+metronidazole). Results Results: 51 cases were identified. Median age was 51 years (range 10 to 87). 54.9% were female and 45.1% male. Infections included intra-abdominal abscesses (n =35), perirectal or scrotal abscesses (10), abdominal wound infections (4), perineal necrotizing fasciitis (1), and cholecystitis (1). Sample types were abscess fluid (43), wound purulence (4) or tissue (3). MDR screen was pos. in 7.8%. Antibiotics were adjusted in 17.6% as a result of the screen report. 31.5% of final antibiotics definitely covered the isolated bacteria, 56.9% possibly covered, and 5.9% did not have an active antibiotic. Among screen pos. cases, final antibiotics definitely covered in 75% and possibly in 25%. Conclusion Conclusions: The MDR Enterobacterales screening tool for abdominal infections had limited impact on final antibiotic choice, but was useful when positive. Further directions include assessment of provider understanding of the MDR screen results and investigation of utility of screen in other infection types. Disclosures All Authors: No reported disclosures