Hemocultivos contaminados: bundle para lograr proporciones aceptables / Blood cultures contaminated: bundle to achieve acceptable proportions

Introducción. El problema de la contaminación de los hemocultivos es muy frecuente en establecimientos de atención hospitalaria, da lugar a la administración de antibióticos innecesarios y prolonga la hospitalización. Objetivo principal. Aplicar un bundle para reducir la proporción de contaminación de hemocultivos. Objetivo secundario. Realizar una encuesta anónima para detectar oportunidades de mejora en la técnica de extracción de hemocultivos. Metodología. Diseño del estudio: Estudio cuasi experimental que evaluó la proporción de contaminación de hemocultivos antes y después de implementar un bundle propio. Se determinó la proporción basal de contaminación de hemocultivos (ene-jul 2022), se realizó la intervención (agosto 2022) y se estableció la proporción de contaminación post intervención (sep.-abril 2023). Intervención: Se analizó la estructura, procedimiento y conocimiento del personal mediante una encuesta propia para detectar áreas de mejora. Se capacitó, a los técnicos de laboratorio, sobre el procedimiento de la toma de muestra mediante una simulación utilizando un brazo artificial. Se diseñó un bundle de seis medidas, se adaptó el procedimiento de toma de hemocultivo y se capacitó al personal. Análisis estadístico. Se analizó la proporción de hemocultivos contaminados entre los periodos pre y post utilizando Chi2 y la relación entre la proporción del periodo pre y post vs la literatura (3.00% contaminación aceptable) utilizando test Z para una proporción. Se consideró un p<0.05 como estadísticamente significativa. Se utilizo el software Stata 8. Resultados. Durante el estudio se analizaron un total de 3,965 hemocultivos. De estos, 1,978 corresponden al periodo pre-intervención y 1,987 corresponden al periodo post intervención. Durante la pre-intervención se detectaron 61 hemocultivos contaminados (3.08% vs 3.00% bibliografía, p:0.5866) mientras que en la etapa post intervención fue de 30 hemocultivos contaminados (1.51% vs 3.00% bibliografía, p:0.0000). La proporción de hemocultivos contaminados se redujo a la mitad, 3.08% vs 1.51%, p: 0.001. Se realizó una encuesta anónima pre y post intervención logrando mejoras en la técnica de toma de hemocultivos. Conclusión. La implementación del bundle propio para la extracción de hemocultivos, permitió reducir la proporción de contaminación a la mitad. El análisis de la encuesta nos permitió identificar oportunidades de mejora en la técnica de recolección de muestra de hemocultivos

Introduction: Contamination of blood cultures is very common in hospital care settings and results in the administration of unnecessary antibiotics and prolongs hospitalization. Main goal: Apply a bundle to reduce the rate of contamination of blood cultures. Secondary objective: Conduct an anonymous survey to detect opportunities for improvement in the blood culture extraction technique. Methodology: Study design: Quasi-experimental study that evaluated the proportion of blood culture contamination before and after implementing its own bundle. The baseline proportion of blood culture contamination was determined (Jan-July 2022), the intervention was performed (August 2022) and the post-intervention contamination proportion was established (September-April 2023). Intervention: The structure, procedure and knowledge of the staff was analyzed through an own survey to detect areas for improvement. Laboratory technicians were trained on the sample collection procedure through a simulation using an artificial arm. A bundle of six measures was designed: (hand hygiene with alcohol gel, use of common gloves and sterile gloves during extraction, antisepsis with alcoholic chlorhexidine gluconate, marking of the blood culture bottle up to the filling level, disinfection of the bottle cap). blood culture bottle with 70% alcohol, safety-lok kit with vacuum extraction system). The procedure was adapted and staff trained. Statistic analysis: The proportion of contaminated blood cultures between the pre and post periods was analyzed using Chi2 and the relationship between the proportion of the pre and post period vs the literature (3.00% acceptable contamination) using Z test for a proportion. P<0.05 was considered statistically significant. Stata 8 software was used.Results: A total of 3,965 blood cultures were analyzed during the study. Of these, 1,978 correspond to the pre-intervention period and 1,987 correspond to the post-intervention period. During the pre-intervention, 61 contaminated blood cultures were detected (3.08%) while in the post-intervention stage there were 30 contaminated blood cultures (1.51%). The proportion of contaminated blood cultures was reduced by half, 3.08% vs 1.51%, p: 0.001. An anonymous survey was carried out pre and post intervention, achieving improvements in the technique of taking blood cultures. Conclusion: The implementation of the own bundle for the extraction of blood cultures allowed the contamination rate to be reduced by ha

Predicting Neonatal Early Onset Sepsis: A 14-Year Cohort Study.

BACKGROUND: In many infants, treatment is started for suspicion of early onset sepsis (EOS), of whom the majority do not have an infection. Early prediction of the absence of a culture-proven sepsis (CPS) would significantly reduce the time of antibiotic treatment and hospitalization. Our objective was to analyze 3 criteria in infants with CPS: positive blood culture (BC) at 24 hours after the onset of suspicion of EOS (OSEOS), C-reactive protein (CRP) ≥10 mg/L and clinical signs of infection, so we can consequently consider to stop antibiotic treatment in infants without these criteria. METHODS: We included all infants with suspicion of EOS from 2007 until 2020. The proportion was calculated of (1) infants with CPS with, at 24 hours, a positive BC and/or CRP ≥10 mg/L and/or clinical signs of infection and (2) infants without CPS with CRP <10 mg/L between 12 and 24 hours after OSEOS. RESULTS: The BC showed growth of a pathogenic microorganism in 50 of 4120 included infants (1.2%). Time to positivity was ≥24 hours in 8 (16%) infants, of whom 7 infants had a raised CRP and/or clinical symptoms of infection within 24 hours. In 1095 (74%) of infants without CPS in whom CRP was measured between 12 and 24 hours after OSEOS, CRP was <10 mg/L. CONCLUSION: A combination of BC, CRP, and clinical signs of infection can diagnose 98% (49/50) of infants with CPS 24 hours after OSEOS. Based on normal CRP and the absence of a positive BC, the decision to stop antibiotics could have been brought forward to 24 hours in 74% of infants.

Underutilization and Quality Gaps in Blood Culture Processing in Public Hospitals of Peru.

Correct processing of blood cultures may impact individual patient management, antibiotic stewardship, and scaling up of antimicrobial resistance surveillance. To assess the quality of blood culture processing, we conducted four assessments at 16 public hospitals across different regions of Peru. We assessed the following standardized quality indicators: 1) positivity and contamination rates, 2) compliance with recommended number of bottles/sets and volume of blood sampled, 3) blood culture utilization, and 4) possible barriers for compliance with recommendations. Suboptimal performance was found, with a median contamination rate of 4.2% (range 0-15.1%), with only one third of the participating hospitals meeting the target value of < 3%; and a median positivity rate of 4.9% (range 1-8.1%), with only 6 out of the 15 surveilled hospitals meeting the target of 6-12%. None of the assessed hospitals met both targets. The median frequency of solitary blood cultures was 71.9% and only 8.9% (N = 59) of the surveyed adult bottles met the target blood volume of 8 - 12 mL, whereas 90.5% (N = 602) were underfilled. A high frequency of missed opportunities for ordering blood cultures was found (69.9%, 221/316) among patients with clinical indications for blood culture sampling. This multicenter study demonstrates important shortcomings in the quality of blood culture processing in public hospitals of Peru. It provides a national benchmark of blood culture utilization and quality indicators that can be used to monitor future quality improvement studies and diagnostic stewardship policies.

Diagnostic yield of routine daily blood culture in patients on veno-arterial extracorporeal membrane oxygenation.

BACKGROUND: Bloodstream infections (BSIs) are frequent on veno-arterial extracorporeal membrane oxygenation (V-A ECMO). Performing routine blood cultures (BCs) may identify early paucisymptomatic BSIs. We investigated the contribution of systematic daily BCs to detect BSIs on V-A ECMO. METHODS: This was a retrospective study including all adult patients requiring V-A ECMO and surviving more than 24 h. Our protocol included routine daily BCs, from V-A ECMO insertion up to 5 days after withdrawal; other BCs were performed on-demand. RESULTS: On the 150 V-A ECMO included, 2146 BCs were performed (1162 routine and 984 on-demand BCs); 190 (9%) were positive, including 68 contaminants. Fifty-one (4%) routine BCs revealed BSIs; meanwhile, 71 (7%) on-demand BCs revealed BSIs (p = 0.005). Performing routine BCs was negatively associated with BSIs diagnosis (OR 0.55, 95% CI [0.38; 0.81], p = 0.002). However, 16 (31%) BSIs diagnosed by routine BCs would have been missed by on-demand BCs. Independent variables for BSIs diagnosis after routine BCs were: V-A ECMO for cardiac graft failure (OR 2.43, 95% CI [1.20; 4.92], p = 0.013) and sampling with on-going antimicrobial therapy (OR 2.15, 95% CI [1.08; 4.27], p = 0.029) or renal replacement therapy (OR 2.05, 95% CI [1.10; 3.81], p = 0.008). Without these three conditions, only two BSIs diagnosed with routine BCs would have been missed by on-demand BCs sampling. CONCLUSIONS: Although routine daily BCs are less effective than on-demand BCs and expose to contamination and inappropriate antimicrobial therapy, a policy restricted to on-demand BCs would omit a significant proportion of BSIs. This argues for a tailored approach to routine daily BCs on V-A ECMO, based on risk factors for positivity.

Time to positivity as a prognostic factor in bloodstream infections with Enterococcus spp.

Time to positivity (TTP) is the delay of time from incubation to blood culture positivity. Short TTP can predict mortality and source of infection. The aim of this study was to investigate the value of TTP of patients with bloodstream infections with enterococci (E-BSI).In a single centre retrospective cohort study in Germany, the data of 244 patients with monomicrobial E-BSI were analyzed with hospital mortality as the primary outcome of interest from January 1 2014 to December 31 2016. Mortality rate of patients with bloodstream infections (BSI) with E. faecalis was 16.7%, Vancomycin sensitive E. faecium (VSEfm) 26.7% and Vancomycin resistant E. faecium (VREfm) 38.2%. Cut-offs showed a significantly higher mortality rate when compared to longer TTP (E. faecalis: P=0.047; VSEfm: P=0.02), but were not risk factors in survival analysis (E.faecalis: HR (hazard ratio): 2.73; P=0.17; VSEfm: HR: 1.63; P=0.15; VREfm: HR: 1.24; P=0.63). TTP≤10.5 hours with E. faecalis BSI was a discriminator for cardiovascular source of infection (AUC: 0.75). A short TTP could predict mortality rates and source of infection but was not an independent parameter for risk of death in survival analysis.

Incidence and utility of follow-up blood cultures in cancer patients with gram-negative bacteremia.

Benefit of follow-up blood cultures (FUBC) in cancer patients with gram-negative bacteremia (GNB) is unknown. Multicenter, retrospective review was performed in adult cancer patients with GNB between January and December 2018. Primary outcome was FUBC incidence. Chi-square, t-tests/Wilcoxon rank-sum, and bivariate regression (logistic/Poisson) analyses compared secondary outcomes (catheter removal, ID consultation, antibiotic duration, length stay, mortality) between patients with versus without FUBC. Of 52 patients with GNB, majority (35/52; 67%) received ≥1 FUBC (mean per patient 3.6, SD 4.3, range 0-29). Majority FUBC had no growth (157/173; 90.8%). Rates of catheter removal and ID consultation were similar between groups (P > 0.05). Patients with FUBC had greater LOS (mean 21 vs 15 days; coefficient = 0.31, CI 0.17-0.45), longer duration of antibiotics (mean 13 vs 11 days, coefficient 0.19, P = 0.013), but no mortality difference (P = 1). FUBC are frequently performed yet infrequently positive in cancer patients with GNB, but were associated with increased LOS and antibiotic duration.

A Retrospective Study of the Optimal Number of Blood Cultures at a Hospital in Japan.

Blood culture tests have a major role in rapid and accurate diagnosis and selection of optimal antibiotic treatment for infectious diseases. The true-positive and contamination rates of blood cultures are performance indicators for the practice of blood culture. However, the optimal number of blood cultures has not been adequately elucidated. We aimed to assess the validity of the number of blood cultures obtained in the hospital. We conducted a retrospective study of blood cultures collected from hospitalized patients between 2010 and 2014 at a tertiary care hospital in Japan and assessed the validity of the number of blood cultures per 1,000 admissions as an indicator for the optimal practice of obtaining blood culture, considering the average length of stay. We also investigated the validity of true-positive and contamination rates of blood cultures in the hospital. The number of blood cultures in this study ranged from 28.6 to 56 per 1,000 patient-days and from 404.4 to 894.6 per 1,000 admissions. The median true-positive and contamination rates of blood cultures per year was 10.1% and 2.8%, respectively. The median contamination rate of blood cultures in a community-acquired group was significantly higher than that in a hospital-acquired group (4.1% vs. 1.9%, p = 0.029). We conclude that there is a possibility that the number of blood cultures per 1,000 admissions is a more appropriate factor to evaluate than per patient-days. Moreover, the true-positive and contamination rates of blood cultures in our hospital are valid.

Turkish pediatric residents' knowledge, perceptions, and practices of blood culture sampling.

INTRODUCTION: Pediatrics is one of the medical specialties in which blood cultures for bloodstream infections are performed very frequently. This study aimed to evaluate pediatric residents' knowledge and perceptions of blood culture sampling. MATERIAL AND METHODS: Between June 2019 and September 2019, a questionnaire comprising 20 questions about blood culture sampling was sent via email to participants who were pediatric residents at five different hospitals in Turkey. There were 11 true/false and nine multiple-choice questions that assessed three aspects of culture sampling: indications, sampling practice and knowledge, and contamination. The percentage of correct answers was used to calculate an overall score and subsection scores. RESULTS: A total of 132 pediatric residents [102 (77%) female] with a mean age of 28.3±2.8 years completed the questionnaire. Forty-five (35%) were in their 1st year of residency. Sixty (46%) participants reported that they had not performed blood culture sampling in the last week. There was a negative relationship between years in training and the number of cultures performed (Kendal's tau-b=-0.297, p<0.001). The overall median score was 65 (range, 35-90) and it seemed to increase with years of training. The lowest median score was in the contamination subscale and only one (0.76%) participant correctly answered all questions concerning contamination. CONCLUSION: Residents who obtained the majority of blood cultures had the lowest knowledge levels. Therefore, it is evident that the knowledge levels of pediatric residents must be increased in order to improve blood culture sampling practices in centers where they perform blood culture sampling.

Molecular Detection of Pathogens in Negative Blood Cultures in the Lao People's Democratic Republic.

Bloodstream infections cause substantial morbidity and mortality. However, despite clinical suspicion of such infections, blood cultures are often negative. We investigated blood cultures that were negative after 5 days of incubation for the presence of bacterial pathogens using specific (Rickettsia spp. and Leptospira spp.) and a broad-range 16S rRNA PCR. From 190 samples, 53 (27.9%) were positive for bacterial DNA. There was also a high background incidence of dengue (90/112 patient serum positive, 80.4%). Twelve samples (6.3%) were positive for Rickettsia spp., including two Rickettsia typhi. The 16S rRNA PCR gave 41 positives; Escherichia coli and Klebsiella pneumoniae were identified in 11 and eight samples, respectively, and one Leptospira species was detected. Molecular investigation of negative blood cultures can identify potential pathogens that will otherwise be missed by routine culture. Patient management would have been influenced in all 53 patients for whom a bacterial organism was identified, and 2.3-6.1% of patients would likely have had an altered final outcome. These findings warrant further study, particularly to determine the cost-benefit for routine use, ways of implementation, and timing of PCR for organisms such as Rickettsia and Leptospira, which are important pathogens in rural Asia.

Impact of delays to incubation and storage temperature on blood culture results: a multi-centre study.

BACKGROUND: Blood cultures are one of the most important tests performed by microbiology laboratories. Many hospitals, particularly in low and middle-income countries, lack either microbiology services or staff to provide 24 h services resulting in delays to blood culture incubation. There is insufficient guidance on how to transport/store blood cultures if delays before incubation are unavoidable, particularly if ambient temperatures are high. This study set out to address this knowledge gap. METHODS: In three South East Asian countries, four different blood culture systems (two manual and two automated) were used to test blood cultures spiked with five common bacterial pathogens. Prior to incubation the spiked blood culture bottles were stored at different temperatures (25 °C, in a cool-box at ambient temperature, or at 40 °C) for different lengths of time (0 h, 6 h, 12 h or 24 h). The impacts of these different storage conditions on positive blood culture yield and on time to positivity were examined. RESULTS: There was no significant loss in yield when blood cultures were stored < 24 h at 25 °C, however, storage for 24 h at 40 °C decreased yields and longer storage times increased times to detection. CONCLUSION: Blood cultures should be incubated with minimal delay to maximize pathogen recovery and timely result reporting, however, this study provides some reassurance that unavoidable delays can be managed to minimize negative impacts. If delays to incubation ≥ 12 h are unavoidable, transportation at a temperature not exceeding 25 °C, and blind sub-cultures prior to incubation should be considered.

Analysis of risk factors, pathogenic bacteria of maternal sepsis in term pregnant women with positive blood culture during hospitalization.

ABSTRACT: The objective of this study was to evaluate the risk factors, pathogenic bacteria and drug sensitivity of maternal sepsis, and provide evidence for clinical prevention and treatment.A retrospective investigation of pregnant women with full-term maternal sepsis was performed to analyze the risk factors, pathogenic bacteria, and drug sensitivity of maternal sepsis.Univariate analysis showed that temperature, serum procalcitonin (PCT) and C-reactive protein (CRP) at admission, white blood cell count (WBC), PCT, CRP and neutrophilic granulocyte percentage (N%) during fever, premature rupture of membranes (PROM), antibiotic use within 1 week, mode of production, onset and duration of fever, between groups were statistically significant (P < .05). Logistic regression analysis showed that cesarean section was an independent risk factor for sepsis (OR = 11.839, 95%CI: 3.121-44.906). Apparent increase was found in body temperature (OR = 3.664, 95%CI: 1.722-7.795), duration of fever (OR = 1.953, 95%CI: 1.242-3.071), and PCT (OR = 1.080, 95%CI: 1.002-1.163). Also, increasing neutrophil ratio (OR = 1.180, 95%CI: 1.073-1.297) indicated a high possibility of maternal sepsis. The organism Escherichia coli (E. coli) was the most common pathogenic bacteria in the positive blood culture group (90%), and the sensitivity to carbapenems (meropenem and imipenem/cilastatin) was 100%, that to piperacillin-tazobactam and amoxicillin sulbactam was over 90%, and that to ceftazidime was 95%.Cesarean section was an independent risk factor for maternal sepsis in term pregnant women with positive blood culture. Besides, the E. coli was the most common pathogenic bacteria in the positive blood culture group. Antibiotics should be used in time and reasonably when the temperature was significantly increased with elevated PCT and N% after a cesarean section.

Análisis estacional de los hemocultivos solicitados desde un servicio de urgencias hospitalario / Seasonal analysis of blood cultures sent from a hospital emergency department

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Characteristics and clinical outcomes of culture-negative and culture-positive septic shock: a single-center retrospective cohort study.

BACKGROUND: We evaluated the characteristics and outcomes of culture-negative versus culture-positive septic shock. METHODS: We performed a retrospective observational study of data from a prospective registry from 2014 to 2018. A total of 2,499 adult patients with septic shock were enrolled. The primary outcome was 90-day mortality, and the secondary outcomes were the length of hospital stay, a requirement for mechanical ventilation or renal replacement therapy, and in-hospital mortality. RESULTS: Of 1,718 patients with septic shock, 1,012 (58.9%) patients were culture-positive (blood 803, urine 302, sputum 102, others 204) and the median pathogen detection time was 9.5 h (aerobic 10.2 h and anaerobic 9.0 h). The most common site of culture-positive infection was the hepatobiliary tract (39.5%), while for the culture-negative it was the lower respiratory tract (38.2%). The culture-negative group had a lower mean body temperature (37.3 vs 37.7 ℃), lactate (2.5 vs. 3.2 mmol/L), C-reactive protein (11.1 vs 11.9 mg/dL), and sequential organ failure assessment score (7.0 vs. 8.0) than that of the culture-positive group. However, 90-day mortality between the groups was not significantly different (32.7 vs 32.2%, p = 0.83), and the other clinical outcomes also did not differ significantly. Moreover, a shorter culture detection time was correlated with a higher sequential organ failure assessment score but not with mortality. CONCLUSION: Patients with septic shock are frequently culture-negative, especially in cases where the infection focus is in the lower respiratory tract. Although culture-negative was associated with a degree of organ dysfunction, it was not an independent predictor of death.

The Diagnostic Yield of Routine Admission Blood Cultures in Critically Ill Patients.

OBJECTIVES: Although the Surviving Sepsis Campaign bundle recommends obtaining blood cultures within 1 hour of sepsis recognition, adherence is suboptimal in many settings. We, therefore, implemented routine blood culture collection for all nonelective ICU admissions (regardless of infection suspicion) and evaluated its diagnostic yield. DESIGN: A before-after analysis. SETTING: A mixed-ICU of a tertiary care hospital in the Netherlands. PATIENTS: Patients acutely admitted to the ICU between January 2015 and December 2018. MEASUREMENTS AND MAIN RESULTS: Automatic orders for collecting a single set of blood cultures immediately upon ICU admission were implemented on January 1, 2017. Blood culture results and the impact of contaminated blood cultures were compared for 2015-2016 (before period) and 2017-2018 (after period). Positive blood cultures were categorized as bloodstream infection or contamination. Blood cultures were obtained in 573 of 1,775 patients (32.3%) and in 1,582 of 1,871 patients (84.5%) in the before and after periods, respectively (p < 0.0001), and bloodstream infection was diagnosed in 95 patients (5.4%) and 154 patients (8.2%) in both study periods (relative risk 1.5; 95% CI 1.2-2.0; p = 0.0006). The estimated number needed to culture for one additional patient with bloodstream infection was 17. Blood culture contamination occurred in 40 patients (2.3%) and 180 patients (9.6%) in the before period and after period, respectively (relative risk 4.3; 95% CI 3.0-6.0; p < 0.0001). Rate of vancomycin use or presumed episodes of catheter-related bloodstream infections treated with antibiotics did not differ between both study periods. CONCLUSIONS: Implementation of routine blood cultures was associated with a 1.5-fold increase of detected bloodstream infection. The 4.3-fold increase in contaminated blood cultures was not associated with an increase in vancomycin use in the ICU.

Clinical impact of pharmacist-directed antimicrobial stewardship guidance following blood culture rapid diagnostic testing.

BACKGROUND: Rapid diagnostic testing (RDT) has been shown to be associated with improved clinical outcomes. AIM: To evaluate the clinical outcomes of using RDT paired with well-defined pharmacist-directed antimicrobial stewardship programme (ASP) guidance to achieve targeted treatment in patients with bacteraemia. METHODS: In this quasi-study, a retrospective (pre-intervention) phase was compared with a prospective (post-intervention) phase. Adult patients with positive blood cultures identified using the BacT/ALERT system were included. Bacterial identification and susceptibility were provided by VITEK 2. During the post-intervention phase, Verigene ASP guidance was developed to optimize antibiotic selection. Pharmacists received the results from the microbiology laboratory, evaluated the appropriateness of current therapy (if any), and communicated the recommended antimicrobial therapy to the treating physician accordingly. FINDINGS: The cohort consisted of 164 patients in the pre-intervention group and 148 patients in the post-intervention group. When comparing the post-intervention period with the pre-intervention period, the median time to culture identification was 22 vs 96 h (P<0.0001), median time to targeted antibiotics was 2 vs 22 h (P<0.0001), median time for antibiotic de-escalation was 12.2 vs 27 h (P<0.0001), and median time to escalation was 1.3 vs 24 h (P<0.003), respectively. In-hospital mortality and 30-day re-admission were significantly lower in the post-intervention group (P<0.003 and 0.034, respectively). Length of hospital stay was significantly shorter in the post-intervention group (6.5 vs 8 days; P=0.03). CONCLUSION: Rapid identification of bacteraemia combined with a pharmacist's recommendation as an ASP initiative significantly improved time to optimal therapy, and may have decreased the risk of mortality and re-admission.

Blood culture sampling rate in hospitalised children as a quality indicator for diagnostic stewardship.

PURPOSE: Recommendations regarding the optimal number of blood cultures in children are not available. The aim of this article is to describe the correlation between blood culture (BC) rates and laboratory-confirmed bloodstream infection (LCBSI) rates, on different paediatric wards of a tertiary-care centre in Germany. METHODS: We conducted a retrospective cohort study in a paediatric university hospital, from 1st January to 31st December 2018. All blood cultures collected from neonatal (NICU) and paediatric intensive-care units (PICU), haematology/oncology, and general paediatric wards were included. There were no exclusion criteria. BC taken/1000 patients-days (BC rates/BCR) and LCBSI/1000 patient-days at risk (LCBSI rates) were calculated for each unit. RESULTS: A total of 6040 patients were admitted to the hospital with 3114 of them into wards studied. Of the 3072 BCs collected, 200 (6.5%) were positive. Collection of BCs was performed in 51/77 (66.2%) of admitted patients on NICU, in 151/399 (37.8%) of PICU patients, in 163/755 (21.6%) of haematology/oncology patients, and in 281/1883 (14.9%) of children on general paediatric wards. Gram-positive bacteria were the most commonly detected organisms in blood cultures from all wards with exception of NICU. The BCR in NICU, PICU, haematology/oncology wards, and general wards were 61.6, 196.2, 358.4, and 52.3, respectively. Excluding commensal pathogens and possible contaminations, the LCBSI rates in the same units were 2.4, 5.6, 4.4, and 1.0, respectively. CONCLUSION: We found different BCR values according the ward studied, being higher in patients with high risk of bloodstream infection such as haematology/oncology patients.

FeBRILe3 Project: protocol for a prospective pragmatic, multisite observational study and safety evaluation assessing Fever, Blood cultures and Readiness for discharge in Infants Less than 3 months old.

INTRODUCTION: The purpose of this observational study is to assess the safety and impact of the introduction of a clinical practice guideline (CPG) recommending early discharge of infants with fever without source who are at low risk of serious bacterial infection (SBI). We hypothesise that implementation of this guideline will be associated with a rate of unplanned readmission to hospital (within 7 days of discharge) which is similar (ie, non-inferior) to that observed under previous standard practice. METHODS AND ANALYSIS: This observational study is a prospective pragmatic, multisite safety assessment and impact project. It will evaluate the safety of a CPG which allows febrile infants fulfilling low-risk criteria to be discharged early from hospital if their blood cultures demonstrate no growth at 24 hours (compared with previous minimum 48 hours admission). This guideline has been implemented at two Western Australian metropolitan hospitals. Infants aged <3 months (chronological or corrected for premature birth before 37 weeks gestation) presenting with fever without source will be included. The primary outcome is readmission to hospital due to clinical deterioration/caregiver concern within 7 days of discharge, identified through review of electronic admission details and study-specific caregiver surveys. Secondary outcomes include rates of SBI, hospital lengths of stay compared with previous practice, clinician guideline adherence and caregiver satisfaction with the discharge process. Analysis will be within a sequential Bayesian safety monitoring framework, which incorporates new information and updates the evidence for guideline safety relative to previous practice (historical control) at prespecified interim analyses. Demographic and clinical information will be summarised. ETHICS AND DISSEMINATION: Ethics approval and waiver of consent for data collection has been granted by the Child and Adolescent Health Service Human Research Ethics Committee (RGS0000001415). Caregivers will have the option to opt out of survey follow-up. Results will be disseminated via peer-reviewed publication. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry (ACTRN12619001010189).

Bacteremia and Blood Culture Utilization during COVID-19 Surge in New York City.

A surge of patients with coronavirus disease 2019 (COVID-19) presenting to New York City hospitals in March 2020 led to a sharp increase in blood culture utilization, which overwhelmed the capacity of automated blood culture instruments. We sought to evaluate the utilization and diagnostic yield of blood cultures during the COVID-19 pandemic to determine prevalence and common etiologies of bacteremia and to inform a diagnostic approach to relieve blood culture overutilization. We performed a retrospective cohort analysis of 88,201 blood cultures from 28,011 patients at a multicenter network of hospitals within New York City to evaluate order volume, positivity rate, time to positivity, and etiologies of positive cultures in COVID-19. Ordering volume increased by 34.8% in the second half of March 2020 compared to the level in the first half of the month. The rate of bacteremia was significantly lower among COVID-19 patients (3.8%) than among COVID-19-negative patients (8.0%) and those not tested (7.1%) (P < 0.001). COVID-19 patients had a high proportion of organisms reflective of commensal skin microbiota, which, when excluded, reduced the bacteremia rate to 1.6%. More than 98% of all positive cultures were detected within 4 days of incubation. Bloodstream infections are very rare for COVID-19 patients, which supports the judicious use of blood cultures in the absence of compelling evidence for bacterial coinfection. Clear communication with ordering providers is necessary to prevent overutilization of blood cultures during patient surges, and laboratories should consider shortening the incubation period from 5 days to 4 days, if necessary, to free additional capacity.

The Neonatal Early Onset Sepsis Calculator; in Clinical Practice.

Aims To determine the impact of applying the Neonatal Early Onset Sepsis Calculator (NEOSC) to clinical practice. We evaluated this multivariable risk prediction model, used in the assessment of infants >35 weeks GA, at risk of neonatal sepsis. Methods A retrospective, cohort study comparing the rates of blood culture use in a large maternity hospital before and after the introduction of the NEOSC. Cases were ascertained from the records of the Department of Microbiology. The key variables were the number of blood cultures (all gestational ages, <72 hours old), infant antibiotic use and sepsis rates. Data for three years prior to NEOSC use (January 2015 - December 2017) were compared with 15 months (January 2018 - Q1 2019) after it was implemented. Results Pre- and post- NEOSC use, the total blood cultures taken annually were: 1,312 (2015), 1,149 (2016), 1,319 (2017) and 702 (2018), 192 (Q1 2019) respectively, a statistically significant reduction [p < 0.00001, 95% CI]. There was no significant difference in rates of either: culture-confirmed GBS-sepsis [p value 0.18, 95% CI] or other-pathogen sepsis [p value 0.32, 95%CI] in term infants between the two periods. There was a significant reduction in antibiotic use in the first 24 hours of life (average 11.3% pre-NEOSC and 5.9% after NEOSC was implemented) [p < 0.00001, 95% CI]. Conclusion The introduction of the NEOSC has reduced blood culture and antibiotic use. This has been achieved without any increase in infection rates.

Distinguishing coagulase-negative Staphylococcus bacteremia from contamination using blood-culture positive bottle detection pattern and time to positivity.

AIM: Detection of coagulase-negative Staphylococcus in blood culture may be a result of either bacteremia or contamination. This often leads to diagnostic uncertainly. Our objective was to develop a method for differentiating whether a coagulase-negative Staphylococcus sp. positive blood culture represents bacteremia or contamination based on positive bottle detection pattern and time to positivity (TTP). METHODS: This study included 155 and 51 adults with positive blood cultures for Staphylococcus epidermidis and Staphylococcus hominis, respectively, over a three-year period from 2016 to 2018. Positive blood culture cases were categorized as either bacteremia or contamination based on the clinically available information, and the detection pattern and TTP in each category were investigated. RESULTS: A total of 57, 92, and 6 S. epidermidis positive blood cultures were categorized as bacteremia, contamination, and undetermined, respectively, whereas 15 and 36 S. hominis positive blood cultures were categorized as bacteremia and contamination, respectively. For positive blood cultures categorized as bacteremia, all four bottles in two sets of blood cultures were positive in 47/47 S. epidermidis and 14/14 S. hominis, respectively, whereas either one bottle in each of two sets or three bottles in two sets were positive in 10/19 S. epidermidis and 1/4 S. hominis, respectively; most of those TTPs were <48 h. Among them, the TTP in catheter-related blood stream infection was <24 h. CONCLUSION: Although clinical assessment is crucial to differentiate between bacteremia and contamination, a combination of positive bottle detection pattern and TTP is a valuable diagnostic auxiliary tool.