Bloodstream infections in pediatric ECLS: usefulness of daily blood culture monitoring and predictive value of biological markers. The British Columbia experience

Introduction: Diagnosis of bloodstream infections using bacteriological cultures suffers from low sensitivity and reporting delay. Advanced molecular techniques introduced in many laboratories provide rapid results and may show improvements in patient outcomes. This study aimed to evaluate the usefulness of a molecular technique, broad-range 16S rRNA PCR followed by sequencing for the diagnosis of bloodstream infections, compared to blood culture in different patient groups. Methodology: Conventional PCR was performed, using broad-range 16S rRNA primers, on blood cultures collected from different patients with suspected bloodstream infections; results were compared with those of blood culture. Results: Though blood culture is regarded as the gold standard, PCR evaluation showed sensitivity of 86.25%, specificity of 91.25%, positive predictive value of 76.67%, negative predictive value of 95.22%, and accuracy of 88.8%. Conclusions: Molecular assays seem not to be sufficient to replace microbial cultures in the diagnosis of bloodstream infections, but they can offer a rapid, good negative test to rule out infection due to their high negative predictive value.

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Electronic Surveillance for Healthcare-Associated Central Line—Associated Bloodstream Infections Outside the Intensive Care Unit

Infection Control and Hospital Epidemiology ◽

10.1086/662181 ◽

2011 ◽

Vol 32 (11) ◽

pp. 1086-1090 ◽

Cited By ~ 35

Author(s):

Keith F. Woeltje ◽

Kathleen M. McMullen ◽

Anne M. Butler ◽

Ashleigh J. Goris ◽

Joshua A. Doherty

Keyword(s):

Intensive Care ◽

Blood Culture ◽

Predictive Value ◽

Chart Review ◽

Positive Culture ◽

Bloodstream Infections ◽

Central Line ◽

Electronic Surveillance ◽

Predictive Values ◽

Best Fit

Background.Manual surveillance for central line-associated bloodstream infections (CLABSIs) by infection prevention practitioners is time-consuming and often limited to intensive care units (ICUs). An automated surveillance system using existing databases with patient-level variables and microbiology data was investigated.Methods.Patients with a positive blood culture in 4 non-ICU wards at Barnes-Jewish Hospital between July 1, 2005, and December 31, 2006, were evaluated. CLABSI determination for these patients was made via 2 sources; a manual chart review and an automated review from electronically available data. Agreement between these 2 sources was used to develop the best-fit electronic algorithm that used a set of rules to identify a CLABSI. Sensitivity, specificity, predictive values, and Pearson's correlation were calculated for the various rule sets, using manual chart review as the reference standard.Results.During the study period, 391 positive blood cultures from 331 patients were evaluated. Eighty-five (22%) of these were confirmed to be CLABSI by manual chart review. The best-fit model included presence of a catheter, blood culture positive for known pathogen or blood culture with a common skin contaminant confirmed by a second positive culture and the presence of fever, and no positive cultures with the same organism from another sterile site. The best-performing rule set had an overall sensitivity of 95.2%, specificity of 97.5%, positive predictive value of 90%, and negative predictive value of 99.2% compared with intensive manual surveillance.Conclusions.Although CLABSIs were slightly overpredicted by electronic surveillance compared with manual chart review, the method offers the possibility of performing acceptably good surveillance in areas where resources do not allow for traditional manual surveillance.

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Rapid identification of Candida glabrata in Candida bloodstream infections

Journal of Medical Microbiology ◽

10.1099/jmm.0.47406-0 ◽

2007 ◽

Vol 56 (12) ◽

pp. 1639-1643 ◽

Cited By ~ 18

Author(s):

Nicholas Foster ◽

Charlotte Symes ◽

Richard Barton ◽

Richard Hobson

Keyword(s):

Blood Culture ◽

Predictive Value ◽

Candida Glabrata ◽

Detection System ◽

Bloodstream Infections ◽

Rapid Identification ◽

Resistant Organism ◽

Blood Culture System ◽

Aerobic Culture ◽

Anaerobic Bottle

Candida species are the fourth most common cause of bloodstream infection (BSI) in the hospitalized patient. Candida glabrata is the most common non-Candida albicans Candida species in England and Wales with an attributed mortality of 48 %. C. glabrata is known to demonstrate reduced susceptibility to fluconazole, resulting in treatment failures when employing this agent for empirical treatment of Candida BSI. The first part of this study demonstrated a technique utilizing a blood culture system commonly used by many laboratories (BACTEC 9240 automated detection system) that reduced the time to identification of this potentially resistant organism by up to 72 h. A presumptive identification was achieved by observing a difference in the duration of incubation required before growth was detected automatically between Lytic Anaerobic and Plus Aerobic culture bottles. Secondly, experiments exploring the growth characteristics of C. glabrata in BACTEC blood culture bottles containing various media were carried out to explore possible reasons underpinning this clinical observation. The detection of yeast in the anaerobic bottle of a blood culture pair consisting of Lytic Anaerobic and Plus Aerobic in a BACTEC 9240 system was found to be highly predictive of the isolation of C. glabrata (positive predictive value 93.3 %, negative predictive value 98.3 %). The reason for this appeared to be a component of the Lytic Anaerobic blood culture medium enhancing the growth of C. glabrata in that medium.

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Proposal for the use of echocardiography in bloodstream infections due to different streptococcal species

BMC Infectious Diseases ◽

10.1186/s12879-021-06391-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Sandra Chamat-Hedemand ◽

Niels Eske Bruun ◽

Lauge Østergaard ◽

Magnus Arpi ◽

Emil Fosbøl ◽

...

Keyword(s):

Risk Factors ◽

Risk Factor ◽

High Risk ◽

Blood Culture ◽

Positive Blood Culture ◽

Bloodstream Infections ◽

Low Risk ◽

Moderate Risk ◽

Streptococcal Species ◽

Very High

Abstract Background Infective endocarditis (IE) is diagnosed in 7–8% of streptococcal bloodstream infections (BSIs), yet it is unclear when to perform transthoracic (TTE) and transoesophageal echocardiography (TOE) according to different streptococcal species. The aim of this sub-study was to propose a flowchart for the use of echocardiography in streptococcal BSIs. Methods In a population-based setup, we investigated all patients admitted with streptococcal BSIs and crosslinked data with nationwide registries to identify comorbidities and concomitant hospitalization with IE. Streptococcal species were divided in four groups based on the crude risk of being diagnosed with IE (low-risk < 3%, moderate-risk 3–10%, high-risk 10–30% and very high-risk > 30%). Based on number of positive blood culture (BC) bottles and IE risk factors (prosthetic valve, previous IE, native valve disease, and cardiac device), we further stratified cases according to probability of concomitant IE diagnosis to create a flowchart suggesting TTE plus TOE (IE > 10%), TTE (IE 3–10%), or “wait & see” (IE < 3%). Results We included 6393 cases with streptococcal BSIs (mean age 68.1 years [SD 16.2], 52.8% men). BSIs with low-risk streptococci (S. pneumoniae, S. pyogenes, S. intermedius) are not initially recommended echocardiography, unless they have ≥3 positive BC bottles and an IE risk factor. Moderate-risk streptococci (S. agalactiae, S. anginosus, S. constellatus, S. dysgalactiae, S. salivarius, S. thermophilus) are guided to “wait & see” strategy if they neither have a risk factor nor ≥3 positive BC bottles, while a TTE is recommended if they have either ≥3 positive BC bottles or a risk factor. Further, a TTE and TOE are recommended if they present with both. High-risk streptococci (S. mitis/oralis, S. parasanguinis, G. adiacens) are directed to a TTE if they neither have a risk factor nor ≥3 positive BC bottles, but to TTE and TOE if they have either ≥3 positive BC bottles or a risk factor. Very high-risk streptococci (S. gordonii, S. gallolyticus, S. mutans, S. sanguinis) are guided directly to TTE and TOE due to a high baseline IE prevalence. Conclusion In addition to the clinical picture, this flowchart based on streptococcal species, number of positive blood culture bottles, and risk factors, can help guide the use of echocardiography in streptococcal bloodstream infections. Since echocardiography results are not available the findings should be confirmed prospectively with the use of systematic echocardiography.

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Scanning Electron Microscope: A New Potential Tool to Replace Gram Staining for Microbe Identification in Blood Cultures

Microorganisms ◽

10.3390/microorganisms9061170 ◽

2021 ◽

Vol 9 (6) ◽

pp. 1170

Author(s):

Gabriel Haddad ◽

Sara Bellali ◽

Tatsuki Takakura ◽

Anthony Fontanini ◽

Yusuke Ominami ◽

...

Keyword(s):

Electron Microscope ◽

Blood Culture ◽

Scanning Electron Microscope ◽

Sample Preparation ◽

Bloodstream Infections ◽

Blood Cultures ◽

Preliminary Identification ◽

Gram Staining ◽

Micro Organisms ◽

Scanning Electron

Blood culture is currently the most commonly used method for diagnosing sepsis and bloodstream infections. However, the long turn-around-time to achieve microbe identification remains a major concern for clinical microbiology laboratories. Gram staining for preliminary identification remains the gold standard. We developed a new rapid strategy using a tabletop scanning electron microscope (SEM) and compared its performance with Gram staining for the detection of micro-organisms and preliminary identification directly from blood cultures. We first optimised the sample preparation for twelve samples simultaneously, saving time on imaging. In this work, SEM proved its ability to identify bacteria and yeasts in morphotypes up to the genus level in some cases. We blindly tested 1075 blood cultures and compared our results to the Gram staining preliminary identification, with MALDI-TOF/MS as a reference. This method presents major advantages such as a fast microbe identification, within an hour of the blood culture being detected positive, low preparation costs, and data traceability. This SEM identification strategy can be developed into an automated assay from the sample preparation, micrograph acquisition, and identification process. This strategy could revolutionise urgent microbiological diagnosis of infectious diseases.

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48. Association of Rapid Pathogen Identification and Pharmacist Intervention on Time to Optimal Antimicrobial Therapy for Bloodstream Infections at Two Community Hospitals

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.093 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S47-S47

Author(s):

Bryant M Froberg ◽

Nicholas Torney

Keyword(s):

Blood Culture ◽

Hospital Mortality ◽

Positive Blood Culture ◽

Antimicrobial Therapy ◽

Length Of Hospital Stay ◽

Bloodstream Infections ◽

Pharmacist Intervention ◽

Pathogen Identification ◽

Community Hospitals ◽

Significant Difference

Abstract Background As many as 1 in 3 patients with bloodstream infections at community hospitals receive inappropriate empiric antimicrobial therapy. Studies have shown that the coupling of real-time intervention with rapid pathogen identification improves patient outcomes and decreases health-system costs at large, tertiary academic centers. The aim of this study was to assess if similar outcomes could be obtained with the implementation of real-time pharmacist intervention to rapid pathogen identification at two smaller, rural community hospitals. Methods This was a pre-post implementation study that occurred from September of 2019 to March 2020. This study included patients ≥18 years of age admitted with one positive blood culture. Patients were excluded if they were pregnant, had a polymicrobial blood culture, known culture prior to admission, hospice consulted prior to admission, expired prior to positive blood culture, or transferred to another hospital within 24 hours of a positive blood culture. Endpoints of patients prior to intervention were compared to patients post-implementation. The primary endpoint was time to optimal antimicrobial therapy. Secondary endpoints included time to effective antimicrobial therapy, in-hospital mortality, length of hospital stay, and overall cost of hospitalization. Results Of 212 patients screened, 88 patients were included with 44 patients in each group. Both groups were similar in terms of comorbidities, infection source, and causative microbial. No significant difference was seen in the mean time to optimal antimicrobial therapy (27.3±35.5 hr vs 19.4± 30 hr, p=0.265). Patients in the post-implementation group had a significantly higher mean hospitalization cost ($24,638.87± $11,080.91 vs $32,722.07±$13,076.73, p=0.013). There was no significant difference in time to effective antimicrobial therapy, in-hospital mortality, or length of hospital stay. Conclusion There were no between-group differences in the primary outcome of time to optimal therapy, with a higher mean hospitalization cost after implementation. These results suggest further antimicrobial stewardship interventions are needed, along with larger studies conducted in the community hospital settings. Disclosures All Authors: No reported disclosures

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Blood culture pellets coupled to MALDI TOF & gram staining to improve fast and accurate microbial diagnosis of bloodstream infections

International Journal of Infectious Diseases ◽

10.1016/j.ijid.2018.04.3556 ◽

2018 ◽

Vol 73 ◽

pp. 58

Author(s):

O. Opota

Keyword(s):

Blood Culture ◽

Bloodstream Infections ◽

Maldi Tof ◽

Gram Staining

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Substantial diagnostic impact of blood culture independent molecular methods in bloodstream infections: Superior performance of PCR/ESI-MS

Scientific Reports ◽

10.1038/s41598-018-34298-7 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 7

Author(s):

Athanasios Makristathis ◽

Nicole Harrison ◽

Franz Ratzinger ◽

Manuel Kussmann ◽

Brigitte Selitsch ◽

...

Keyword(s):

Blood Culture ◽

Bloodstream Infections ◽

Molecular Methods ◽

Superior Performance ◽

Diagnostic Impact ◽

Esi Ms ◽

Culture Independent

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A Comparison of Blood Pathogen Detection Among Droplet Digital PCR, Metagenomic Next-Generation Sequencing, and Blood Culture in Critically Ill Patients With Suspected Bloodstream Infections

Frontiers in Microbiology ◽

10.3389/fmicb.2021.641202 ◽

2021 ◽

Vol 12 ◽

Author(s):

Bangchuan Hu ◽

Yue Tao ◽

Ziqiang Shao ◽

Yang Zheng ◽

Run Zhang ◽

...

Keyword(s):

Next Generation Sequencing ◽

Blood Culture ◽

Critically Ill ◽

Critically Ill Patients ◽

Pathogen Detection ◽

Bloodstream Infections ◽

Digital Pcr ◽

Droplet Digital Pcr ◽

Next Generation ◽

Generation Sequencing

Metagenomic next-generation sequencing (mNGS) and droplet digital PCR (ddPCR) have recently demonstrated a great potential for pathogen detection. However, few studies have been undertaken to compare these two nucleic acid detection methods for identifying pathogens in patients with bloodstream infections (BSIs). This prospective study was thus conducted to compare these two methods for diagnostic applications in a clinical setting for critically ill patients with suspected BSIs. Upon suspicion of BSIs, whole blood samples were simultaneously drawn for ddPCR covering 20 common isolated pathogens and four antimicrobial resistance (AMR) genes, mNGS, and blood culture. Then, a head-to-head comparison was performed between ddPCR and mNGS. A total of 60 episodes of suspected BSIs were investigated in 45 critically ill patients, and ddPCR was positive in 50 (83.3%), mNGS in 41 (68.3%, not including viruses), and blood culture in 10 (16.7%) episodes. Of the 10 positive blood cultures, nine were concordantly identified by both mNGS and ddPCR methods. The head-to-head comparison showed that ddPCR was more rapid (~4 h vs. ~2 days) and sensitive (88 vs. 53 detectable pathogens) than mNGS within the detection range of ddPCR, while mNGS detected a broader range of pathogens (126 vs. 88 detectable pathogens, including viruses) than ddPCR. In addition, a total of 17 AMR genes, including 14 blaKPC and 3 mecA genes, were exclusively identified by ddPCR. Based on their respective limitations and strengths, the ddPCR method is more useful for rapid detection of common isolated pathogens as well as AMR genes in critically ill patients with suspected BSI, whereas mNGS testing is more appropriate for the diagnosis of BSI where classic microbiological or molecular diagnostic approaches fail to identify causative pathogens.

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Development and Clinical Validation of a Droplet Digital PCR Method for Detection of Acinetobacter baumannii and Klebsiella pneumonia in Patients with Suspected Bloodstream Infections

10.22541/au.162337143.35366523/v1 ◽

2021 ◽

Author(s):

Yang Zheng ◽

Jun Jin ◽

Ziqiang Shao ◽

Jingquan Liu ◽

Run Zhang ◽

...

Keyword(s):

Blood Culture ◽

Acinetobacter Baumannii ◽

Limit Of Detection ◽

Early Stage ◽

Bloodstream Infections ◽

Digital Pcr ◽

Droplet Digital Pcr ◽

Klebsiella Pneumonia ◽

Clinical Validation ◽

Blood Samples

The relatively long turnaround time and low sensitivity of traditional blood culture may delay the effective antibiotic therapy in patients with bloodstream infection (BSI). To reduce the morbidity and mortality of BSI, a rapid and sensitive pathogen detection method is urgently required. Acinetobacter baumannii and Klebsiella pneumonia are two major microorganisms responsible for BSI. Here we reported a novel droplet digital PCR (ddPCR) method that can detect A. baumannii and K. pneumonia in whole blood samples within 4 h, with a specificity of 100% for each strain and limit of detection at 0.93 copies/microliter for A. baumannii and 0.27 copies/microliter for K. pneumonia. Clinical validation in 170 patients with suspected BSIs showed that, compared with blood culture that reported 4 (2.4%) A. baumannii cases and 7 (4.1%) K. pneumonia cases, ddPCR detected 23 (13.5%) A. baumannii cases, 26 (15.3%) K. pneumonia cases, and 4 (2.4%) dual infection cases, including the 11 positive patients reported by blood culture. In addition, the positive patients reported by ddPCR alone (n = 42) had significantly lower serum concentrations of procalcitonin and lactate, SOFA and APACHE II scores, and 28-day mortality than those reported by both blood culture and ddPCR (n = 11), suggesting that patients with less severe manifestations can potentially benefit from the guidance of ddPCR results. In conclusion, our study suggests that ddPCR represents a sensitive and rapid method to identify causal pathogens in blood samples and to guide the treatment decisions in the early stage of BSI.

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