Risk Factors For Multidrug-resistant Organisms Research Articles

Bloodstream infections due to multi-drug resistant bacteria in the emergency department: prevalence, risk factors and outcomes-a retrospective observational study.

Multidrug-resistant organisms (MDROs) are prevalent in patients admitted to the Emergency Department (ED) and increase the risk of inappropriate empirical antibiotic therapy. Risk stratification for MDRO infection is essential to early identify patients requiring empirical broad-spectrum antibiotic therapy, but it remains challenging for emergency physicians. This study aimed to evaluate prevalence, risk factors, and outcomes of patients admitted to the ED with a bloodstream infection (BSI) caused by MDROs. A retrospective observational study enrolling all consecutive adult patients admitted with a BSI to the ED of Niguarda Hospital, Italy, from January 2019 to December 2021 was performed. 757 patients were enrolled, 14.1% with septic shock. 156 (20%) patients had a BSI caused by MDRO: extended-spectrum beta-lactamase (ESBL) producing Enterobacterales were the most prevalent followed by methicillin-resistant Staphylococcus aureus (MRSA). Risk factors for BSI due to MDRO and specifically for ESBL were chronic renal failure (OR 2.2; 95%CI 1.4-3.6), nursing home residency (OR 4.4; 95%CI 1.9-10.2) and antibiotic therapy in the last 90-days (OR 2.6; 95%CI 1.7-4), whereas for MRSA were dialysis (OR 12.3; 95%CI 1.8-83), antibiotic therapy and/or hospital admission in the past 90-days (OR 3.6; 95%CI 1.2-10.6) and ureteral stent or nephrostomy (OR 7.8; 95%CI 1.5-40.9). Patients with BSI due to MDRO had a higher rate of inappropriate empirical antibiotic therapy (50%) and longer length of stay, but no higher in-hospital mortality. Among patients admitted to the ED with a BSI, MDROs are frequent and often associated with inappropriate empirical antibiotic therapy. Specific updated risk factors for MDRO may help clinicians to better identify patients requiring a broader antibiotic therapy in the ED, while awaiting microbiological results.

Natural Language Processing (NLP) Accurately Identifies LTCF Exposure from Clinical Notes: A Proof-of-Principle Study

Background: Residence or recent stay in a long-term care facility (LTCF) is one of the most important risk factors for multidrug-resistant organism (MDRO) carriage and infection, making reliable identification of LTCF-exposed inpatients a critical priority for infection control day-to-day practice and research. However, because most hospital electronic health records (EHRs) do not include a dedicated field for documenting LTCF exposure, absent manual review of patient charts, identifying LTCF-exposed inpatients is challenging. We aimed to develop an automated, natural language processing (NLP)-based classifier for identifying LTCF exposure from clinical notes. Methods: We randomly sampled 1020 adult admissions from 2016-2021 across the 12-hospital University of Maryland Medical System and manually reviewed each admission’s history & physical (H&P) note for mention of LTCF exposure (Figure 1). After H&P pre-processing, we calculated feature representations for documents based on term frequencies and visually explored between-group (LTCF-exposed vs. LTCF-unexposed) feature differences. To predict LTCF status from the H&P notes, we trained and tuned a LASSO regression-based classifier on 70% of the data with 3-fold cross-validation and 1:1 up-sampling to address class imbalance. The final classifier was evaluated on the 30% held-out sample (not up-sampled), with calculation of the C-statistic (area-under-the-curve, AUC) with bootstrapped 95% confidence intervals, and construction of receiver-operating-characteristic and variable importance plots (R Version 4.3.2). Results: 7% (n=76 cases) of H&P notes documented LTCF exposure. In our visual analysis, the H&P words and phrases that were over-represented among LTCF patients had high face validity (Figure 2). The final LASSO-regression-based classifier achieved a C-statistic of 0.89 (95% CI: 0.80–0.98) on the held-out data for identifying LTCF exposure from the H&P notes (Figure 3). The most important model predictors (i.e., words) for distinguishing LTCF-exposed from LTCF-unexposed patients are reflected in Figure 4. The most important predictor-words of LTCF-exposure were “rehab,” “place,” “status,” “egd,” and “dementia.” Conclusion: In this multi-center study, even a simple NLP classifier demonstrated very strong discrimination for identifying LTCF exposure status from H&P notes, which could substantially reduce the manual review time required to identify LTCF-exposed inpatients. If automated in the electronic health record, it could also inform real-time MDRO screening decisions. Future research is planned to build more sophisticated classifiers using machine learning best practices, to build classifiers for additional MDRO risk factors, and to externally validate NLP classifiers on notes from an external healthcare system.

Endoscopic retrograde cholangiopancreatography-obtained bile culture in acute cholangitis: retrospective analysis of bile cultures and risk factors in a tertiary care center.

Collection of bile aspirate during endoscopic retrograde cholangiopancreatography (ERCP) is essential to identify pathogens responsible for acute cholangitis. Limited data are available on the risk factors for the presence of multidrug-resistant organisms (MDRO) in bile. We conducted this retrospective, single-center study to assess the prevalence and susceptibility rates of bacteria in bile cultures, and the risk factors for the presence of pathogens, MDRO, and fungi in bile. All consecutive patients who underwent biliary drainage for acute cholangitis from January 2017 to December 2019 were included. 443/1610 ERCPs were performed for acute cholangitis. Bile culture was collected in 91.4% (405/443), of which 86.7% were positive. Most common isolates were Enterococcus faecalis (37.6%) and Escherichia coli (32.8%). Vancomycin resistance was found in 9.9% of Enterococcus species (spp.); extended-spectrum beta-lactamases (ESBL) and carbapenemases in 11.2% and 0.9% of Enterobacteriaceae, respectively. The empiric antimicrobial therapy was changed in 26.4% (n=107) of cases, with a clinical response in 90.7%. In multivariate analysis, biliary stenting was an independent risk factor for positive bile culture (odds ratio [OR] 9.43; P<0.01). Independent risk factors for MDRO in bile were patient age>60years (OR 2.51; P=0.03), previous sphincterotomy (OR 2.57; P=0.02), and biliary stenting (OR 2.80; P<0.01). Previous sphincterotomy was the only risk factor for isolation of fungi in bile (OR 1.61; P=0.04). Our study showed an increasing prevalence of Enterococcus spp. and MDRO. Bile cultures should be routinely collected in cholangitis and in patients with repeated ERCPs to allow more efficient antimicrobial treatment.

Effectiveness of tailored screening for multidrug-resistant organisms upon admission to an intensive care unit in the United Arab Emirates.

Multidrug-resistant organism (MDRO) screening may identify high-risk patients for MDRO infection and curb the spread of these resistant pathogens. However, the heterogeneous practices in MDRO screening and the diversity of MDRO risk factors necessitate a tailored approach for successful implementation. This study aimed to evaluate the performance of tailored MDRO screening in predicting MDRO carriage compared to universal screening. Critically ill patients who underwent MDRO screening tests upon intensive care unit admission between September 2015 and December 2019 were included in the study. A risk-predicting model was developed using risk factors identified through multivariable logistic regression analysis. If an individual had one or more identified risk factors, the individual was deemed to be at risk of MDRO carriage and undergo tailored screening. The sensitivity of tailored screening was compared with universal screening for methicillin-resistant Staphylococcus aureus (MRSA)and multidrug-resistant Gram-negative bacilli (carbapenem-resistant Acinetobacter baumannii and carbapenem-resistant Enterobacterales). The use of tracheostomy or endotracheal tubes, previous antibiotic exposure, previous multidrug-resistant Gram-negative bacilli carriage history, admission to the medical department, peripheral vascular disease, and liver disease were associated with positive screening for multidrug-resistant Gram-negative bacilli. These six risk factors accounted for all positive screening for multidrug-resistant Gram-negative bacilli, requiring 38.6% of all tests. Notably, MRSA had different risk factor profiles, and the risk factor-based screening approach detected only 43.1% (31 out of 72) of MRSA-positive cases. Tailored screening based on identified risk factors showed variable sensitivities to individual MDROs compared to universal screening. A tailored screening approach for individual MDROs may enhance the overall effectiveness of MDRO screening programs.

Multidrug-Resistant Bacterial Infections Among Very Low Birthweight Infants With Late-Onset Sepsis in Johannesburg, South Africa.

An estimated 2.4 million babies died within the first 28 days of life in 2020. The third leading cause of neonatal death continues to be neonatal sepsis. Sepsis-causing bacterial pathogens vary temporally and geographically and, with a rise in multidrug-resistant organisms (MDROs), pose a threat to the neonatal population. This was a single-center, retrospective study of very low birth weight (VLBW) infants with late-onset sepsis (LOS) admitted to a neonatal unit in South Africa. We aimed to calculate the prevalence of multidrug-resistant (MDR) infections in this population. The data collected included demographic and clinical characteristics, length of hospital stay, risk factors for MDRO and mortality, and microbiology results. Logistic regression was used to assess the association between prespecified risk factors with MDR infections and mortality. Of 2570 VLBW infants admitted, 34% had LOS, of which 33% was caused by MDROs. Infection with Acinetobacter spp., Pseudomonas spp., extended-spectrum beta-lactamase Klebsiella spp., or Escherichia coli was associated with the highest mortality in the LOS cohort. Infants with congenital infections (adjusted odds ratio [aOR], 5.13; 95% CI, 1.19-22.02; P = .028) or a history of necrotizing enterocolitis (aOR, 2.17; 95% CI, 1.05-4.49; P = .037) were at significantly higher risk for MDR infections. More than one-third of LOS cases in VLBW infants were caused by MDROs in this study. MDR infections cause substantial neonatal mortality. Antimicrobial stewardship programs, infection control protocols, and ongoing surveillance are needed to prevent further emergence and spread of MDR infections worldwide.

Initial blood culture collection practices and the associated factors upon continued empiric piperacillin-tazobactam usage

Background: Approaches to the prescription behavior of broad-spectrum antibiotics, including preauthorization and prospective audit and feedback (PAF), are a focus of antimicrobial stewardship (ASP). However, preprescription behavior, such as blood-culture collection before empiric prescription, is understudied and merits more attention given its influence on the usage of broad-spectrum antibiotics. At the University of Tokyo Hospital, carbapenems are subject to PAF, which has resulted in a compensatory increase in piperacillin-tazobactam use. To evaluate the inherent preprescription behavior associated with a broad-spectrum antibiotic, we investigated the initial blood-culture collection practices upon hospitalization in patients who were continued on empiric piperacillin-tazobactam. Methods: A retrospective observational study was conducted at the University of Tokyo Hospital, a tertiary-care hospital in Tokyo, Japan. Patients who were administered piperacillin-tazobactam on the day of hospitalization between April 2016 and December 2017 were included. Patients aged &lt;=18 years and/or patients who discontinued piperacillin-tazobactam within two days were excluded. Only 1 admission per patient was kept for analysis. The medical records of 250 randomly selected patients were reviewed to obtain data on demographics, blood-culture collection, severity, specialties, and risk factors for multidrug-resistant organisms. A multivariable logistic regression analysis was used to identify factors associated with blood-culture collection. Results: In total, 960 discrete patients fulfilled the study criteria. Of the randomly selected 250 patients, blood cultures were collected from 162 patients (64.8%), and microbial growth was observed in 30 cases (18.5%). Enterobacterales and anaerobes accounted for 73.3% of the microbial population. Gastroenterologists (94, 37.6%) and general surgeons (52, 20.8%) were the most common prescribers. Hepatobiliary (83, 33.2%), respiratory (58, 23.2%), and intra-abdominal infections (IAI; 34, 13.6%) were the major suspected diagnoses. Blood-culture collection was associated with the use of immunosuppressive agents (OR, 3.48; 95% CI, 1.49–8.99), intrabdominal infection (OR, 0.28; 95% CI, 0.12–0.67), systemic inflammatory response syndrome criteria ≥ 2 (OR, 4.50; 95% CI, 2.25–9.42), and surgical specialty (OR, 0.33; 95% CI, 0.18–0.60). Conclusions: More than one-third of patients requiring hospitalization and empiric piperacillin-tazobactam did not undergo blood-culture collection. The finding that blood cultures were less likely to be obtained in patients with suspected IAI requiring hospitalization and by surgical specialties raises a concern regarding suboptimal evaluation. Further assessment of the appropriateness of blood-culture collection in the setting of broad-spectrum antibiotic prescription and tailored promotion of blood-culture collection to surgical specialties may be warranted.Disclosures: S.K.: The author (during graduate school (PhD) was involved in antiviral research relevant to a neglected tropical disease and favipiravir. During this graduate school research, favipiravir was provided by FUJIFILM Toyama Chemical Co. Ltd

Assessment of risk factors associated with multidrug-resistant organism infections among patients admitted in a tertiary hospital - a retrospective study

BackgroundBacterial resistance has become a global health concern. To treat suspected multidrug resistant organisms (MDROs), physicians first use broad-spectrum antibiotics; however, this increases the chance of developing antimicrobial resistance. Thus, defining the risk factors for MDROs could aid in the selection of the ideal initial antimicrobial therapy and improve clinical outcomes. ObjectiveThis study aimed to identify the common risk factors for MDRO infection among patients admitted to King Fahad Hospital (KFH) and to analyze the comorbidity factors associated with MDRO infections. MethodsThis retrospective, observational, case-control study included adult patients ≥ 18 years old admitted to KFH between 1st of January to 31st of March 2021, with positive microbial culture. Pediatric patients, outpatients, or patients with only positive fungal cultures were excluded. Data were obtained from the KFH laboratory MDRO documenting database. ResultsTwo hundred and seventy patients were included in this study: 136 in the study group and 134 in the control group. Among patients, 167 (61.9 %) were males and 184 (68.1%) were 18 to 65 years old. The use of drugs such as cotrimoxazole, amikacin, and imipenem (OR = 4.331, C. I. of OR:1.728, 10.855, p = 0.002) were significantly associated with MDRO infections, whereas cefazolin was associated with a lower risk of MDRO infections (OR = 0.080, C.I. of OR:0.018, 0.347, p < 0.001). The intensive care unit showed higher odds of significant association with MDRO infections than those of the surgical unit (odds ratio [OR] = 8.717, 95% C.I. of OR: 3.040, 24.998, p < 0.001). Patients who previously consumed acid-suppressive medications showed higher odds of developing MDRO infections (OR = 5.333, C.I. of OR: 2.395, 11.877, p < 0.001). ConclusionThe most significant comorbidities were diabetes, hypertension, antibiotic use prior to hospitalization and the use of cotrimoxazole, amikacin and imipenem among other antibtiotics was mostly associated with MRDO infections. This study revealed an increasing trend of MDRO infections and a positive correlation with the incidence of strokes and mortality, which highlights the importance of understanding the risk factors for MDRO infections.

Risk Factors for Multidrug-Resistant Organisms Infection in Diabetic Foot Ulcer.

ObjectiveThe aim of this study is to analyze the microbiological characteristics of diabetic foot ulcer (DFU) and drug resistance of multidrug-resistant organisms (MDROs) and to reveal the potential risk factors for MDROs. This provides a basis for early empiric antibiotic treatment.MethodsThis study included 348 patients with diabetic foot ulcer in Chu Hsien-I Memorial Hospital & Metabolic Disease Hospital of Tianjin Medical University between May 2020 and November 2021. A total of 475 strains of bacteria were cultured, among which 240 strains were multidrug-resistant bacteria, accounting for 51%. Binary logistic regression was used to analyze risk factors. First, univariate analysis was used to calculate the p value of variables, and then multivariate analysis was conducted for variables with p < 0.1 to analyze independent risk factors. Risk factors with p < 0.05 in multivariable analysis were considered as independent risk factors. The strength of the association was represented by odds ratio and 95% confidence interval.ResultsUnivariable logistic regression analysis demonstrated that previous hospitalization, previous antibiotic therapy, ulcer size >4cm2, surgical therapy, D-dimer, and CRP were associated with MDRO infection in patients with DFU. Multivariate logistic regression analysis demonstrated that previous hospitalization (OR = 1.91; 95% CI = 1.11–3.28; p = 0.02), ulcer size >4cm2 (OR = 1.68; 95% CI = 1.03–2.76; p = 0.04), surgical therapy (OR = 2.14; 95% CI = 1.03–4.47; p = 0.04), and CRP (OR = 1.01; 95% CI = 1.00–1.01; p = 0.03) were independent risk factors for MDROs infection in diabetic foot patients. Drug resistance analysis may indicate that the proportion and drug resistance rate of Acinetobacter baumannii in Tianjin, China, have changed.ConclusionPrevious hospitalization, ulcer size >4cm2, surgical therapy and CRP were independent risk factors for MDROs infection in diabetic foot patients. Identifying these risk factors can help us identify the high-risk patients of diabetic foot with MDRO infection early. More attention to high-risk patients and more aggressive isolation precautions may reduce the incidence of MDRO infection in diabetic foot patients.

Analysis of risk factors for multidrug-resistant organisms in diabetic foot infection

BackgroundTo study the bacteriological characteristics, risk factors, and treatment of multi-drug resistance (MDR) organisms in patients with diabetic foot infection.MethodsPatients with diabetic foot ulcer admitted to hospital from June 2018 to December 2019 (n = 180) were selected as clinical subjects. Demographic information, routine blood test, wound culture and sensitivity were collected. Risk factors of MDR bacteria were analyzed.ResultsAmong 180 patients with diabetic foot ulcer, 146 were positive in bacterial culture, with 84 positive in MDR bacteria. A total of 182 strains were isolated, with 104 strains being multi-drug resistant. Body mass index, glycosylated hemoglobin, fasting blood glucose, triglyceride, course of ulcer, size of ulcer, peripheral neuropathy, peripheral vascular disease, osteomyelitis, peripheral blood leukocyte count, percentage of neutrophils, and previous use of antibiotics were the related factors of infection of MDR bacteria in diabetic foot ulcer patients (P < 0.05). The leukocyte count and neutrophil ratio of MDR-bacilli were lower than those of non MDR-bacilli (P < 0.05).ConclusionThe risk of MDR bacteria in diabetic foot infection is high. It is necessary to evaluate the risk of multidrug-resistant bacteria by characterizing the course of disease, metabolic control, local ulcer and other aspects in order to formulate an effective treatment plan. The decrease of leukocyte count and neutrophil ratio may be related to damage of the host immune response.

1298. Validation of Local Pseudomonas aeruginosa Risk Factors in Patients with Community-Onset Bacterial Pneumonia

BackgroundClinical guidelines for community-acquired pneumonia (CAP) encourage validation of local risk factors for multidrug-resistant organisms. This study aimed to validate previously derived, local risk factors for Pseudomonas aeruginosa in patients with community-onset bacterial pneumonia at Prisma Health-Midlands’ hospitals. MethodsIn this retrospective, observational cohort study, adult patients hospitalized with pneumonia MS-DRG codes from January 1, 2017 to March 31, 2020 were randomly screened. Enrolled subjects were admitted to 1 of 3 Prisma Health-Midlands’ hospitals with: diagnosis of pneumonia; receipt of inpatient antibiotics within 48 hours of symptom onset; receipt of over 48 hours of antibiotic therapy; and a causative bacterial pathogen identified via respiratory or blood culture, urinary antigen, or respiratory multiplex PCR panel. Performance of the locally derived score was compared to the Drug Resistance in Pneumonia (DRIP) Score, IDSA 2019 CAP guideline risk factors, and healthcare-associated pneumonia (HCAP) risk factors. Endpoints included sensitivity, specificity, positive and negative predictive value, overall accuracy, and over- and undertreatment rates. Overall accuracy was defined as a case in which the gram-negative antibiotic coverage recommended by the scoring schema would have been appropriate for the identified organism, i.e. neither overtreatment (overly broad-spectrum) nor undertreatment (inadequate spectrum). ResultsOf 713 patients screened, 36 patients met criteria and were enrolled. The most common bacterial pathogens identified were Pseudomonas aeruginosa (n = 10, 27.8%) and Streptococcus pneumoniae (n = 10, 27.8%). Performance characteristics for each scoring schema are summarized in Table 1.Table 1. Performance characteristics of risk scores predicting for Pseudomonas aeruginosa community-onset bacterial pneumonia. MDRO=multidrug-resistant organism; DRIP=Drug Resistance in Pneumonia Score; IDSA=Infectious Diseases Society of America 2019 Community-Acquired Pneumonia Guideline risk factors ; HCAP=healthcare-associated pneumonia risk factorsConclusionCompared to DRIP or IDSA 2019 CAP risk scores, the local risk score performed well at ruling out resistant gram-negatives given its higher specificity and lower overtreatment rate; yet, it did not perform as well at ruling in resistant gram-negatives given a lower sensitivity and undertreatment rate. All scores performed better than HCAP risk factors. Data from this study will be utilized to further refine the local risk score algorithm. Disclosures P. Brandon Bookstaver, Pharm D, ALK Abello, Inc. (Grant/Research Support, Advisor or Review Panel member)Biomerieux (Speaker’s Bureau)Kedrion Biopharma (Grant/Research Support, Advisor or Review Panel member) Hana Winders, PharmD, BCIDP, biomerieux (Grant/Research Support) Julie Ann Justo, PharmD, MS, BCPS-AQ ID, bioMerieux (Speaker’s Bureau)Merck & Co. (Advisor or Review Panel member)Therapeutic Research Center (Speaker’s Bureau)Vaxart (Shareholder)

Observational study over 8-year period evaluating microbiological characteristics and risk factor for isolation of multidrug-resistant organisms (MDRO) in patients with healthcare-associated infections (HAIs) hospitalized in a urology ward.

Objective: To analyze, in a urology ward, the prevalence and characteristics of healthcare-associated infections (HAIs) due to multidrug-resistant organisms (MDRO).Methods: We carried out an observational study from 2012 to 2019, evaluating MDRO among patients with HAIs, who were hospitalized in the urology ward. MDRO include Pseudomonas spp., resistant to at least three antibiotic groups, extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae or those resistant to carbapenems, and Enterococcus spp. resistant to vancomycin.Results: Among patients with HAIs, MDRO were isolated in 100 out of 438 (22.8%) positive cultures. Univariate and multivariate analyses reported that prior urinary tract infection (UTI) [OR 2.45; 95% CI 1.14–5.36; p=0.021] and immunosuppression [OR 2.13; 95% CI 1.11–4.10; p=0.023] were risk factors for MDRO. A high prevalence of MRDO was found in patients with a catheter in the upper urinary tract; 27.6% for double J stent, 29.6% in those with a nephrostomy tube, and 50% in those with a percutaneous internal/external nephroureteral (PCNU) stent. MDRO were isolated in 28.4% of cultures with Enterobacteriaceae (23.8% and 44.7% in those with E. coli and Klebsiella spp.); 7% of Enterobacteriaceae showed resistance to carbapenems (1.3% and 10% for E. coli and Klebsiella spp., respectively). Three out of 80 Enterococcus spp. were vancomycin-resistant. The rate of Pseudomonas aeruginosa resistant to at least three antibiotic groups was 36.3%.Conclusions: The isolation of MDRO, in up to 25% of positive cultures in a urology ward, constitutes a challenge for the selection of antibiotics. MDRO are more common in immunosuppressed patients, those with previous UTIs, and those with a catheter in the upper urinary tract.

Identification of Risk Factors for Multidrug-Resistant Organisms in Community-Acquired Bacterial Pneumonia at a Community Hospital

Background: The 2019 Infectious Disease Society of America (IDSA) guidelines for the management of community-acquired bacterial pneumonia encourage the identification of locally validated risk factors for methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa to guide empiric therapy decisions for patients with community-acquired pneumonia (CAP). The guidelines urge clinicians to perform local validation to determine prevalence and risk factors pertinent to their institution. Objective: To determine the percentage of community-acquired pneumonia caused by multidrug-resistant organisms (MDROs) and assess risk factors potentially associated with multidrug-resistant organisms CAP at our hospital. Methods: This was a retrospective case control study analyzing patients admitted to the 344-bed community hospital with bacterial community-acquired pneumonia between January 1, 2019 and December 31, 2019. Univariate analysis and multivariate regression were performed to assess potential risk factors for MDRO pathogens. Results: MDROs were isolated in 41.3% of patients with culture-positive CAP (n=19/46), and 3.6% of patients with microbiological culture data within 48 hours of admission (19/527). Among patients with culture-positive CAP, hospitalization in the previous 90 days and receipt of antibiotics in the previous 90 days occurred more frequently in MDRO patients than non-MDRO patients (37% vs 11%, P=.032). No risk factors reached statistical significance in the multivariate regression. There were no differences in clinical outcomes between MDRO and non-MDRO patients. Conclusions: This study demonstrated a low overall prevalence of MDRO pathogens in patients with CAP. Potential risk factors for MDRO included hospitalization within the past 90 days and antibiotic use within the past 90 days.

Incidence, impact and risk factors for multidrug-resistant organisms (MDRO) in patients with major trauma: a European Multicenter Cohort Study.

The burden of MDRO in health systems is a global issue, and a growing problem. We conducted a European multicenter cohort study to assess the incidence, impact and risk factors for multidrug-resistant organisms in patients with major trauma. We conducted this study because the predictive factors and effects of MDRO in severely injured patients are not yet described. Our hypothesis is that positive detection of MDRO in severely injured patients is associated with a less favorable outcome. Retrospective study of four level-1 trauma centers including all patients after major trauma with an injury severity score (ISS) ≥ 9 admitted to an intensive care unit (ICU) between 2013 and 2017. Outcome was measured using the Glasgow outcome scale (GOS). Of 4131 included patients, 95 (2.3%) had a positive screening for MDRO. Risk factors for MDRO were male gender (OR 1.73 [95% CI 1.04-2.89]), ISS (OR 1.01 [95% CI 1.00-1.03]), PRBC's given (OR 1.73 [95% CI 1.09-2.78]), ICU stay > 48h (OR 4.01 [95% CI 2.06-7.81]) and mechanical ventilation (OR 1.85 [95% CI 1.01-3.38]). A positive MDRO infection correlates with worse outcome. MDRO positive cases GOS: good recovery = 0.6%, moderate disability = 2.1%, severe disability = 5.6%, vegetative state = 5.7% (p < 0.001). MDRO in severely injured patients are rare but associated with a worse outcome at hospital discharge. We identified potential risk factors for MDRO in severely injured patients. Based on our results, we recommend a standardized screening procedure for major trauma patients.

Patterns of Oral Antibiotic Use and Excess Duration at Hospital Discharge

Background: Antimicrobial stewardship (AMS) interventions have predominantly involved inpatient antimicrobial therapy. However, for many hospitalized patients, most antibiotic use occurs after discharge, and unnecessarily prolonged courses of therapy are common. Patient transition from hospitalization to discharge represents an important opportunity for AMS intervention. We describe patterns of antibiotic use selection and duration of therapy (DOT) for common infections including discharge antibiotics. Methods: This retrospective cross-sectional analysis was derived from an IRB-approved, multihospital, quasi-experiment at a 5-hospital health system in southeastern Michigan. The study population included patients discharged from an inpatient general and specialty practice ward on oral antibiotics from November 2018 through April 2019. Patients were included with the following diagnoses: skin and soft-tissue infections (SSTIs), community-acquired pneumonia (CAP), hospital-acquired pneumonia (HAP), respiratory viral infections, acute exacerbation of chronic obstructive pulmonary disease (AECOPD), intra-abdominal infections (IAIs), and urinary tract infections (UTIs). Other diagnoses were excluded. Data were extracted from medical records including antibiotic indication, selection, and duration, as well as patient characteristics. Results: In total, 1,574 patients were screened and 800 patients were eligible for inclusion. The most common antibiotic indications were respiratory tract infections, with 487 (60.9%) patients. These included 165 AECOPD cases (20.6%) and 200 CAP cases (25%) with no multidrug resistant organism (MDRO) risk factors; 57 patients (7.1%) with MDRO risk factors; HAP in 7 patients (0.9%); and influenza in 58 patients (7.2%). Also, 205 (25.6%) patients were diagnosed with UTIs: 71 with cystitis (8.9%), 86 (10.8%) with complicated UTI (cUTI), and 48 (6%) with pyelonephritis. Furthermore, 125 patients (15.6%) were diagnosed with SSTI: 59 (7.4%) purulent and 66 (8.3%) nonpurulent. 31 (3.9%) patients had an IAI. The most commonly used antibiotics were cephalosporins in 536 patients (67%), azithromycin in 252 patients (31.5%), and fluroquinolones and tetracyclines in 231 patients (28.9%). Fluroquinolones were the most frequent antibiotic prescribed at discharge in 210 patients (26.3%). Figure 1 displays the average DOT relative to specific indications. The median duration of total antibiotic therapy exceeded institutional guideline recommendation for multiple conditions, including AECOPD (7 days vs recommended 5 days), CAP with COPD (8.3 vs 7 days ), CAP without COPD (7.7 vs 5 days), and pyelonephritis (11 vs 7–10 days). Also, 269 (33.6%) patients received unnecessary therapy; 218 (27.3%) of these were due to excess duration. Conclusions: Among a cross-section of hospitalized patients, the average DOT, including after discharge, exceeded the optimal therapy for many patients. Further understanding of patterns and influences of antibiotic prescribing is necessary to design effective AMS interventions for improvement.Funding: This work was completed under CDC contract number 200-2018-02928.Disclosures: None

Low Carriage Rates of Multidrug-Resistant Organisms in Prospective Stool Donors in a Large Fecal Microbiota Transplantation (FMT) Stool Bank

Background: Fecal microbiota transplantation (FMT) has emerged as standard of care for Clostridioides difficile not responsive to antibiotic therapy. Rigorous screening of healthy donors is critical to patient safety. As part of routine donor evaluation for FMT, multidrug-resistant organism (MDRO) screening is performed to assess the presence of extended-spectrum β-lactamase–producing organisms (ESBLs), vancomycin-resistant enterococci (VRE), carbapenem-resistant Enterobacteriaceae (CRE), and methicillin-resistant Staphylococcus aureus (MRSA). Carriage rates of these organisms in a healthy, low-risk population are largely unknown. We report MDRO carriage rates among individuals screened for a stool donation program at a large-scale FMT stool bank. Methods: Individuals were screened at a nonprofit stool bank (OpenBiome, Cambridge, MA). Potential donors underwent in-person clinical assessment, including MDRO risk factors (eg, travel, occupation, healthcare exposure). If they met the clinical assessment criteria, laboratory testing, including MDROs, was performed. Once enrolled in the donor program, donors underwent repeated clinical and laboratory screening at 60-day intervals, with intermittent health checks throughout the donation period. Stool samples provided at 60-day intervals were screened for MDROs (ie, ESBL, CRE, VRE), and nasal swabs for MRSA were tested using culture-based methods. All stool samples tested for MDROs from prospective and enrolled donors were included. Results: Between February 2017 and July 2019, 247 individuals were screened for MDROs. Overall, 11 samples (0.04%) tested positive for ESBL, MRSA, or VRE. No CRE carriers were identified. Also, 2 individuals tested positive twice for ESBL, resulting in 13 of 1,688 (0.77%) positive screens. International travel in the previous 12 months was reported by 6 of 11 MDRO carriers. Occupations typically associated with MDROs were not observed in carriers. Most of the MDRO-positive donors were students; however, students make up the majority of the stool donor cohort. Conclusions: This study is the first to report background MDRO carriage rates in a population of otherwise healthy FMT stool donors. Although rare, MDROs were detected and should be part of standard guidelines for FMT donor screening. Most subjects testing positive for MDROs had defined risk factors associated with MDRO carriage, including international travel or exposure to healthcare environments. However, occupational exposure was not a factor associated with carriage in this study. Standardized donor screening guidelines for FMT are urgently needed to ensure that MDROs and risk factors for MDRO carriage are routinely screened for by all FMT providers. Stool banks present a unique public health opportunity to evaluate the background carriage rate of MDROs in healthy populations.Funding: NoneDisclosures: None

Impact of Inappropriate Antibiotic Therapy in Vancomycin-Resistant Enterococcus Bacteremia.

Vancomycin-resistant Enterococcus (VRE) bacteremia has significant morbidity and mortality. Empiric antibiotic regimens for treating patients with risk factors for multidrug-resistant organisms may not have medications directed at treating VRE. To evaluate the impact of antibiotic therapy (and other risk factors) on mortality in VRE bacteremia. We identified 146 patients with VRE bacteremia, admitted at our institution over an 11 years period (2004-2014). All inpatients with an initial positive VRE blood culture were included only once in the analysis. Eighteen patients were excluded from the study because of inability to retrieve medical information regarding one or more important study variables. The retrospectively collected data from electronic medical records of 128 patients were analyzed. The inpatient, 30-day, and 1-year mortality rates from VRE bacteremia were 23%, 31%, and 59%, respectively. Only 19% patients were discharged home. Inappropriate antibiotics were prescribed in 19% patients. Appropriate antibiotics were prescribed in 81% patients (62% daptomycin and 37% linezolid); however, only 58% patients received appropriate antibiotics within 24 hours of the reported positive blood cultures. The 30-day and 1-year mortality rates for patients treated with inappropriate antibiotics were 54% and 67% compared with 26% and 50%, respectively, for those treated with appropriate antibiotics. The median survival rate for patients treated with inappropriate antibiotics was 1 month (95% confidence interval: 0.0-1.0) compared with 11 months (95% confidence interval: 4.0-13.0) for those treated with appropriate antibiotics. The advanced patient age (median age 75 years vs. 63 years) was a significant risk factor for inappropriate antibiotic therapy (P value = 0.02). The multivariate Cox regression model revealed inappropriate antibiotic therapy (P value = 0.003), septic shock (P value = 0.0004), albumin (P value = 0.04), and dementia (P value = 0.003) to be associated with 30-day mortality. Our study highlights the detrimental effect of inappropriate antibiotic therapy and other risk factors on morbidity and mortality associated with VRE bacteremia.

Risk factors for multidrug-resistant organisms among deceased organ donors.

Donor infection or colonization with a multidrug-resistant organism (MDRO) affects organ utilization and recipient antibiotic management. Approaches to identifying donors at risk of carrying MDROs are unknown. We sought to determine the risk factors for MDROs among transplant donors. A multicenter retrospective cohort study was conducted at four transplant centers between 2015 and 2016. All deceased donors who donated at least one organ were included. Cultures obtained during the donor's terminal hospitalization and organ procurement were evaluated. The primary outcome was isolation of an MDRO on culture. Multivariable Cox regression was used to determine risk factors associated with time to donor MDRO. Of 440 total donors, 64 (15%)donors grew an MDRO on culture. Predictors of an MDRO on donor culture included hepatitis C viremia (hazard ratio [HR] 4.09, 95% confidence interval [CI] 1.71-9.78, P=.002), need for dialysis (HR 4.59, 95% CI 1.09-19.21, P=.037), prior hematopoietic cell transplant (HR 7.57, 95% CI 1.03-55.75, P=.047), and exposure to antibiotics with a narrow gram-negative spectrum (HR 1.13, 95% CI 1.00-1.27, P=.045). This is the first study to determine risk factors for MDROs among deceased donors and will be important for risk stratifying potential donors and informing transplant recipient prophylaxis.

Aspiration Pneumonia in Older Adults.

Aspiration pneumonia refers to an infection of the lung parenchyma in an individual that has inhaled a bolus of endogenous flora that overwhelms the natural defenses of the respiratory system. While there are not universally agreed upon criteria, the diagnosis can be made in patients with the appropriate risk factors and clinical scenario, in addition to a radiographic or an ultrasonographic image of pneumonia in the typical dependent lung segment. Treatment options for aspiration pneumonia vary based on the site of acquisition (community-acquired aspiration pneumonia [CAAP] versus healthcare-associated aspiration pneumonia [HCAAP]), the risk for multidrug-resistant (MDR) organisms, and severity of illness. Hospitalized CAAP patients without severe illness and with no risk for MDR organisms or Pseudomonas aeruginosa (PA) can be treated with standard inpatient community-acquired pneumonia therapy covering anaerobes. Patients with CAAP and either of the following-risk factors for MDR pathogens, septic shock, need for an intensive care unit (ICU) admission, or mechanical ventilation-can be considered for broader coverage against anaerobes, methicillin-resistant Staphylococcus aureus (MRSA), and PA. Severe aspiration pneumonia that originates in a long-term care facility or HCAAP with one or more risk factors for MDR organisms should be considered for similar treatment. HCAAP with one or more risk factors for MDR organisms or PA, plus septic shock, need for ICU admission or mechanical ventilation should receive double coverage for PA in addition to coverage for MRSA and anaerobes. Multiple gaps in current understanding and management of aspiration pneumonia require future research, with a particular focus on antibiotic stewardship.

Spontaneous bacterial peritonitis in patients with cirrhosis: incidence, outcomes, and treatment strategies.

Spontaneous bacterial peritonitis is the most frequent bacterial infection in patients with cirrhosis. The reported incidence varies between 7% and 30% in hospitalized patients with cirrhosis and ascites, representing one of their main complications. Outcomes in patients with spontaneous bacterial peritonitis are poor since acute kidney injury, acute-on-chronic liver failure, and death occur in as much as 54%, 60%, and 40% of the patients, respectively, at midterm. Early antibiotic treatment of spontaneous bacterial peritonitis is crucial. However, the landscape of microbiological resistance is continuously changing, with an increasing spread of multidrug-resistant organisms that make its current management more challenging. Thus, the selection of the empirical antibiotic treatment should be guided by the severity and location where the infection was acquired, the risk factors for multidrug-resistant organisms, and the available information on the local expected bacteriology. The use of albumin as a complementary therapy for selected high-risk patients with spontaneous bacterial peritonitis is recommended in addition to antibiotics. Even though antibiotic prophylaxis has proven to be effective to prevent spontaneous bacterial peritonitis, a careful selection of high-risk candidates is crucial to avoid antibiotic overuse. In this article we review the pathogenesis, risk factors, and prognosis of spontaneous bacterial peritonitis, as well as the current evidence regarding its treatment and prophylaxis.

188. A Novel Inpatient Antibiotic Stewardship Assistance Program (ASAP) Using Real-Time Electronic Health Record Data, Prediction Modeling and Epidemiologic Data to Provide Personalized Empiric Antibiotic Recommendations

BackgroundAntibiotic prescribing varies amongst clinicians, which can result in inappropriate or overuse. Inappropriate antibiotics can increase the risk of adverse drug events and multi-drug-resistant organisms (MDRO). Decreasing variability and increasing alignment with guideline-based therapy may improve antimicrobial stewardship and outcomes.MethodsWe developed a point of care stewardship tool embedded in the electronic health record (EHR) that provides empiric antibiotic recommendations for four syndromes, urinary tract infection (UTI), abdominal biliary infection (ABI), pneumonia, and cellulitis. We identified key variables that alter antibiotic selection or need for infectious disease (ID) consultation such as allergy history, immunosuppression and risk factors for MDRO, and mortality. We created algorithms of preferred empiric antibiotic choices based on national and hospital guidelines using these risk factors. We used a weighted incidence syndromic combined antibiogram (WISCA) prediction model to recommend ID consultation when likelihood of coverage was below a defined threshold. We also incorporated a home-grown epidemiologic tool that takes real-time data from outpatient clinics on incidence of influenza-like-illness (ILI) to recommend influenza PCR testing during periods of high ILI risk. Data on risk factors and WISCA variables including demographics, allergy history, ICD10 codes, vitals, laboratories, and microbiology results were extracted in real-time from the EHR and sent via URL into a web server which has an embedded Windows ASP.NET C# web site and an SQL server database. The web server was then embedded back into the EHR. This tool stores recommendations into the database for stewardship auditing.ResultsThirteen key and 20 WISCA variables are extracted from the EHR in real-time. There are eight distinct antibiotic recommendations for UTI and ABI, 12 for cellulitis, and 40 for pneumonia. An illustration of the ASAP tool is shown in Figure 1.ConclusionASAP is an HER-embedded platform that provides clinicians access to personalized antibiotic prescribing tied to best practices and optimal stewardship initiatives. Future work will look into the tool’s effect on variation in care, antibiotic prescribing, and outcomes.Figure 1:Disclosures All authors: No reported disclosures.