847. The Effect of Antimicrobial Administration on Blood Culture Positivity in Patients with Severe Manifestations of Sepsis

Abstract Background Current guidelines recommend obtaining blood cultures prior to antimicrobial therapy in patients with sepsis. Administering antimicrobials immediately without waiting for blood cultures could potentially decrease time to treatment and improve outcomes, but it is unclear the degree to which this strategy impacts diagnostic yield. Methods We performed a patient-level, single-arm, diagnostic trial. Seven urban emergency departments affiliated with academic medical centers across Canada and the United States participated in the study. Adults ≥18 years of age presenting to the emergency department with evidence of severe manifestations of sepsis, including a systolic blood pressure <90 mmHg and/or a serum lactate ≥4 mmol/L were included. Study participants had 2 sets of blood cultures drawn prior to and immediately following antimicrobial administration. The primary outcome was the difference in blood culture pathogen recovery rates before and after administration of antimicrobial therapy. Results Of the 3,164 participants screened, 325 were included in the study (mean age, 65.6 years; 63.0% men) and had repeat blood cultures drawn after the initiation of antimicrobial therapy (median time of 70 minutes, IQR 50 to 110 minutes). Pre-antimicrobial blood cultures were positive for one or more microbial pathogens in 102/325 (31.4%) patients. Fifty-four participants (52.9%) had matching blood culture results after initiation of antimicrobial treatment. The absolute difference in pathogen recovery rates was 14.5% ([95% CI 8.0 to 21.0%]; P < 0.0001) between pre- and post-antimicrobial blood cultures. Results were consistent in an analysis of the per-protocol population (absolute difference, 13.3% [95% CI 6.1 to 20.4%]; P < 0.0001). Including the results of other microbiological cultures done as part of routine care, microbial pathogens were recovered in 69 of 102 (67.7%) participants (absolute difference, 10.2% [95% CI 3.4 to 16.8%]; P < 0.0001). Conclusion Among patients with severe manifestations of sepsis, the administration of empiric antimicrobial therapy significantly reduces the yield of pathogen recovery when blood cultures are drawn shortly after treatment initiation. Disclosures All Authors: No reported Disclosures.

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Delayed treatment of bacteremia during the COVID-19 pandemic

Diagnosis ◽

10.1515/dx-2020-0114 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Taiju Miyagami ◽

Yuki Uehara ◽

Taku Harada ◽

Takashi Watari ◽

Taro Shimizu ◽

...

Keyword(s):

Blood Culture ◽

Delayed Diagnosis ◽

Chest Ct ◽

Blood Cultures ◽

Emergency Unit ◽

Medical Providers ◽

Delayed Treatment ◽

Clinical Measures ◽

Primary Measure ◽

Antimicrobial Administration

Abstract Objectives Coronavirus disease (COVID-19) blindness, that is, the excessive consideration of the disease in diagnosis, has reportedly led to delayed diagnosis of some diseases. We compared several clinical measures between patients admitted for bacteremia during the two months of the COVID-19 pandemic and those admitted during the same period in 2019. We hypothesized that the pandemic has led to delayed treatment of bacteremia. Methods This retrospective observational study compared several measures undertaken for patients who visited the emergency unit in two hospitals between March 1 and May 31, 2020, during the COVID-19 pandemic and whose blood cultures tested positive for bacteremia with those for corresponding patients treated during the same period in 2019. The primary measure was time from consultation to blood culture/antimicrobials. Results We included 29 eligible patients from 2020 and 26 from 2019. In 2020, the time from consultation to antimicrobial administration was significantly longer than in 2019 (mean [range], 222 [145–309] min vs. 139 [102–179] min, p=0.002). The frequency of chest computed tomography (CT) was significantly higher in 2020 (96.6 vs. 73.1%, p=0.021). Significant differences were not observed in the time to blood culture or chest CT preceding the blood culture between the two periods. Conclusions Our findings suggested that due to the COVID-19 epidemic/pandemic, focusing on the exclusion of its infection using CT scans leads to an overall delay in the diagnosis and treatment of bacteremia. Medical providers must be aware of COVID-19 blindness and evaluate patients objectively based on rational criteria and take appropriate action.

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HIV-Associated Mycobacterium tuberculosis Bloodstream Infection Is Underdiagnosed by Single Blood Culture

Journal of Clinical Microbiology ◽

10.1128/jcm.01914-17 ◽

2018 ◽

Vol 56 (5) ◽

Cited By ~ 5

Author(s):

David A. Barr ◽

Andrew D. Kerkhoff ◽

Charlotte Schutz ◽

Amy M. Ward ◽

Gerry R. Davies ◽

...

Keyword(s):

South Africa ◽

Mycobacterium Tuberculosis ◽

Blood Culture ◽

Confidence Interval ◽

Bloodstream Infection ◽

Diagnostic Yield ◽

Blood Cultures ◽

Prospective Evaluation ◽

Content Type ◽

Time Point

ABSTRACT We assessed the additional diagnostic yield for Mycobacterium tuberculosis bloodstream infection (BSI) by doing more than one tuberculosis (TB) blood culture from HIV-infected inpatients. In a retrospective analysis of two cohorts based in Cape Town, South Africa, 72/99 (73%) patients with M. tuberculosis BSI were identified by the first of two blood cultures during the same admission, with 27/99 (27%; 95% confidence interval [CI], 18 to 36%) testing negative on the first culture but positive on the second. In a prospective evaluation of up to 6 blood cultures over 24 h, 9 of 14 (65%) patients with M. tuberculosis BSI had M. tuberculosis grow on their first blood culture; 3 more patients (21%) were identified by a second independent blood culture at the same time point, and the remaining 2 were diagnosed only on the 4th and 6th blood cultures. Additional blood cultures increase the yield for M. tuberculosis BSI, similar to what is reported for nonmycobacterial BSI.

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P32 An audit to assess the suitability of patients at a tertiary/quaternary paediatric hospital to switch from intravenous (IV) to oral (PO) antimicrobial therapy

Archives of Disease in Childhood ◽

10.1136/archdischild-2020-nppg.41 ◽

2020 ◽

Vol 105 (9) ◽

pp. e23.1-e23

Author(s):

Orlagh McGarrity ◽

Aliya Pabani

Keyword(s):

High Risk ◽

Antimicrobial Resistance ◽

Blood Culture ◽

Antimicrobial Stewardship ◽

Antimicrobial Therapy ◽

Blood Cultures ◽

Antimicrobial Use ◽

List Type ◽

Paediatric Hospital ◽

Oral Agents

Introduction, Aims and ObjectivesIn 2011 the Start Smart then Focus campaign was launched by Public Health England (PHE) to combat antimicrobial resistance.1 The ‘focus’ element refers to the antimicrobial review at 48–72 hours, when a decision and documentation regarding infection management should be made. [OM1] At this tertiary/quaternary paediatric hospital we treat, immunocompromised, high risk patients. In a recent audit it was identified that 80% of antimicrobial use is IV, this may be due to several factors including good central access, centrally prepared IV therapy and oral agents being challenging to administer to children. The aim of the audit was to assess if patient have a blood culture prior to starting therapy, have a senior review at 48–72 hours, and thirdly if our high proportion of intravenous antimicrobial use is justified.MethodElectronic prescribing data from JAC was collected retrospectively over an 8 day period. IV antimicrobials for which there is a suitable oral alternative, this was defined as >80% bioavailability, were included. Patients were excluded in the ICU, cancer and transplant setting, those with absorption issues and with a high risk infection, such as endocarditis or bacteraemia. Patient were assessed against a set criteria to determine if they were eligible to switch from IV to PO therapy; afebrile, stable blood pressure, heart rate <90/min, respiratory rate < 20/min for 24 hours. Reducing CRP, reducing white cell count, blood cultures negative or sensitive to an antibiotic that can be given orally.Results100% of patients (11) had a blood cultures taken within 72 hours of starting therapy55% of patients had a positive blood culture82% of patients had a senior review at 48–72 hours46% of patients were eligible to switch from IV to PO therapy at 72 hours33% of eligible patients were switched from IV to PO therapy at 72 hoursConclusion and RecommendationsThis audit had a low sample size due to the complexity of the inclusion and exclusion criteria, and the difficulty in reviewing patient parameters on many different hospital interfaces. It is known that each patient is reviewed at least 24 hourly on most wards and therefore there is a need for improved documentation of prescribing decisions. Implementation of an IV to oral switch guideline is recommended to support prescribing decisions and educate and reassure clinicians on the bioavailability and benefits of PO antimicrobial therapy where appropriate. Having recently changed electronic patient management systems strategies to explore include hard stops on IV antimicrobial therapies, however this will require much consideration. Education of pharmacist and nurses is required to raise awareness about antimicrobial resistance and the benefits of IV to PO switches, despite the ease of this therapy at out Trust. This will promote a culture in which all healthcare professionals are active antimicrobial guardians, leading to better patient outcomes, less service pressures, and long term financial benefit.ReferenceGOV.UK. 2019. Antimicrobial stewardship: Start smart - then focus. [ONLINE]Available at: https://www.gov.uk/government/publications/antimicrobial-stewardship-start-smart-then-focus [Accessed 3 July 2019]

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Controlled Comparative Evaluation of BacT/Alert FAN and ESP 80A Aerobic Media as Means for Detecting Bacteremia and Fungemia

Journal of Clinical Microbiology ◽

10.1128/jcm.36.9.2686-2689.1998 ◽

1998 ◽

Vol 36 (9) ◽

pp. 2686-2689 ◽

Cited By ~ 14

Author(s):

Gary V. Doern ◽

Ann Barton ◽

Sudah Rao

Keyword(s):

Blood Culture ◽

Antimicrobial Therapy ◽

Enhanced Recovery ◽

Tertiary Care ◽

Blood Cultures ◽

Two Systems ◽

Absorbing Material ◽

Clinically Significant ◽

One Year ◽

Organism Group

During a one-year period, a total of 6,305 blood cultures were processed in a tertiary-care teaching hospital; 6 to 12 ml of blood was inoculated into both a BacT/Alert Fan aerobic bottle and an ESP 80A aerobic bottle. The FAN aerobic bottle contains an antimicrobial-absorbing material; the 80A aerobic bottle does not. Bottles were processed on their respective continuous-monitoring blood culture instruments for up to five days of incubation. Four hundred thirty-three cultures (6.9%) representing 301 septic episodes in 235 different patients yielded 490 bacteria or yeasts thought to be clinically significant. Two hundred seventy-five of the 433 presumed clinically significant positive cultures (63.5%) representing 195 septic episodes and yielding 301 isolates were positive in both FAN and 80A bottles. One hundred nine significant positive cultures (25.2%) (i.e., cultures positive with an organism judged to be of probable clinical significance) from 70 septic episodes yielded 126 isolates only in FAN bottles. Conversely, the 80A bottle was exclusively positive in 49 instances (11.3%), representing 36 septic episodes and yielding 63 isolates. The higher rates of significant positive blood cultures, numbers of septic episodes documented, and numbers of isolates recovered in FAN bottles versus 80A bottles were all statistically significant (P < 0.05). Enhanced rates of detection of presumed clinically significant isolates in FAN bottles were largely accounted for by Staphylococcus aureus, members of the Enterobacteriaceae, and non-Pseudomonas aeruginosa miscellaneous gram-negative bacilli from patients receiving antimicrobial therapy at the time blood cultures were obtained. Enhanced recovery of one organism group, the β-hemolytic streptococci, occurred in 80A. With one exception, detection times were essentially equivalent in the two systems. The single exception pertained to streptococci and enterococci, which were recovered significantly faster in 80A bottles. Three hundred thirty-eight of the 6,305 blood cultures evaluated in this study (5.4%) were judged likely to be contaminated. The percentages of probable contaminated cultures were as follows: 26.6% FAN and 80A; 42.3% FAN only; 31.1% 80A only (P < 0.05). Finally, the instrument false-positive rates for the two systems were 0.7% with FAN and 3.0% with 80A (P < 0.05). We conclude that while contamination rates were slightly higher with FAN than with 80A, use of FAN aerobic bottles in conjunction with the BacT/Alert system will yield significantly higher numbers of clinically significant blood culture isolates than 80A bottles and the ESP system. Furthermore, this enhanced detection is most conspicuous in patients receiving antimicrobial therapy at the time blood cultures are performed, probably due to the presence of an antimicrobial-absorbing material in FAN aerobic bottles.

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Streptobacillus moniliformis mitral valve endocarditis and septic arthritis: the challenges of diagnosing rat-bite fever endocarditis

Infectious Disease Reports ◽

10.4081/idr.2018.7731 ◽

2018 ◽

Vol 10 (2) ◽

Cited By ~ 6

Author(s):

Daisy Torres-Miranda ◽

Madhi Moshgriz ◽

Marc Siegel

Keyword(s):

United States ◽

Mitral Valve ◽

Blood Culture ◽

The United States ◽

Blood Cultures ◽

Native Valve ◽

Native Valve Endocarditis ◽

Streptobacillus Moniliformis ◽

Rat Bite Fever ◽

Mitral Valve Vegetation

Streptobacillus moniliformis, the cause of rat-bite fever (RBF) in the United States, has rarely been reported as a cause of infectious endocarditis. In the majority of previously reported cases, the diagnosis was clinically based in patients with underlying valvular abnormalities in the setting of positive blood culture for Streptobacillus moniliformis. We report a case of native valve endocarditis secondary to Streptobacillus moniliformis in a woman with a mitral valve vegetation but negative blood cultures where the diagnosis was established using molecular diagnostics on the valvular tissue.

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

BMC Infectious Diseases ◽

10.1186/s12879-021-05872-8 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Clare L. Ling ◽

Tamalee Roberts ◽

Sona Soeng ◽

Tomas-Paul Cusack ◽

David A. B. Dance ◽

...

Keyword(s):

Blood Culture ◽

Storage Temperature ◽

Storage Conditions ◽

Significant Loss ◽

Blood Cultures ◽

Multi Centre Study ◽

Middle Income ◽

Ambient Temperatures ◽

Different Temperatures ◽

Pathogen Recovery

Abstract 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.

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Blood Culture Contamination in a Community Hospital- less than 2% is achievable

American Journal of Clinical Pathology ◽

10.1093/ajcp/aqab191.271 ◽

2021 ◽

Vol 156 (Supplement_1) ◽

pp. S127-S127

Author(s):

R Bedi ◽

J Atkinson

Keyword(s):

Emergency Department ◽

Blood Culture ◽

Positive Blood Culture ◽

Antimicrobial Therapy ◽

False Positive ◽

Community Hospital ◽

Blood Cultures ◽

Proper Order ◽

Multiple Devices ◽

American Society

Abstract Introduction/Objective Blood cultures are commonly obtained to evaluate the presence of bacteria or fungal infection in a patient’s bloodstream. The presence of living microorganisms circulating in the bloodstream is of substantial prognostic and diagnostic importance. A positive blood culture indicates a reason for the patient’s illness and provides the etiological agent for antimicrobial therapy. Collection of blood culture is an exact process that requires time, the proper order of draw, and following of correct protocol. The busy Emergency department that requires multiple demands for nurse’s time, turnover of staff, rushing from one task to another can result in the improper collection and false-positive blood cultures. The national benchmark is set at 3% by the American Society of Clinical Microbiology (ASM) and The Clinical and Laboratory Standard Institute (CLSI). False-positive blood culture results in increased length of stay and unnecessary antimicrobial therapy, resulting in an increased cost burden to the hospital of about $5000 per patient. Methods/Case Report At our 150-bed community hospital, 26 beds Emergency Department, we have come a long way in reduction of our blood culture contamination rates from upwards of 4% to less than 2%, far lower than the national benchmark. Results (if a Case Study enter NA) NA Conclusion There are multiple devices available from various manufacturers claiming to reduce blood culture contamination. These devices do reduce blood culture (BC) contamination but at an added cost of the device. The rate of BC can be reduced and less than 3% is achievable by materials available in the laboratory. We have achieved this by providing training to every new staff by demonstration and direct observation, providing everything required for collection in a kit, using proper technique, the inclusion of diversion method that involves the aseptic collection of a clear tube before collecting blood cultures, and following up monthly on any false positive blood cultures.

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An Evaluation Of Direct Identification Of Pathogens From Blood Cultures By Maldi-Tof Mass Spectrometry

Sveikatos mokslai ◽

10.5200/sm-hs.2016.074 ◽

2016 ◽

Vol 26 (5) ◽

pp. 69-73

Author(s):

Lina Savickaitė ◽

Jelena Kopeykinienė

Keyword(s):

Mass Spectrometry ◽

Blood Culture ◽

Positive Blood Culture ◽

Antimicrobial Therapy ◽

Rapid Identification ◽

Blood Cultures ◽

Direct Identification ◽

Maldi Tof Mass Spectrometry ◽

Maldi Tof ◽

Mass Spectrometry Identification

Rapid identification of the infecting organism may aid in choosing appropriate antimicrobial therapy. We used MALDI-TOF mass spectrometry to identify bacteria directly from the positive blood culture samples (n=21). 85,71 percent of these results was identified using of MALDI-TOF mass spectrometry. Identification time of bacteria directly from the blood culture takes more than 1 hour for 27,8 percent results.

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Recovery of Gram-Negative Bacteria from Aerobic Blood Culture Bottles Containing Antibiotic Binding Resins after Exposure to β-Lactam and Fluoroquinolone Concentrations

Journal of Clinical Microbiology ◽

10.1128/jcm.00849-19 ◽

2019 ◽

Vol 57 (10) ◽

Cited By ~ 2

Author(s):

Iris H. Chen ◽

David P. Nicolau ◽

Joseph L. Kuti

Keyword(s):

Blood Culture ◽

Blood Cultures ◽

Binding Kinetics ◽

Gram Negative Bacteria ◽

Content Type ◽

E Coli ◽

Trough Concentrations ◽

Pathogen Recovery ◽

The Impact ◽

Antibiotic Dose

ABSTRACT Blood culture bottles containing antibiotic binding resins are routinely used to minimize artificial sterilization in the presence of antibiotics. However, the resin binding kinetics can differ between antibiotics and concentrations. This study assessed the impact of clinically meaningful peak, midpoint, and trough concentrations of meropenem, imipenem, cefepime, cefazolin, levofloxacin, and piperacillin-tazobactam on the recovery of Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae from resin-containing BacT/Alert FA Plus and Bactec Aerobic/F blood culture bottles. P. aeruginosa-inoculated bottles alarmed positive in 4/20 (20%), 16/20 (80%), and 20/20 (100%) of those with peak, midpoint, and trough concentrations of antipseudomonal agents, respectively (P ≤ 0.001). E. coli was recovered from 8/24 (33%), 11/24 (46%), and 14/24 (58%) of bottles with peak, midpoint, and trough concentrations, respectively (P = 0.221). K. pneumoniae was recovered from 8/16 (50%) at all concentrations of the studied antibiotics (P = 1.0). BacT/Alert and Bactec bottles inoculated with antibiotics and P. aeruginosa had similar times to detection (TTD) (P = 0.352); however, antibiotic-containing BacT/Alert bottles had a shorter TTD compared with antibiotic-containing Bactec bottles for E. coli (P = 0.026) and K. pneumoniae (P ≤ 0.001). Pathogen recovery in BacT/Alert FA Plus and Bactec Aerobic/F blood culture bottles containing antibiotic binding resins was greatly reduced in the presence of antibiotics, especially at higher concentrations. These data support the practice of drawing blood cultures immediately before an antibiotic dose to maximize the chances of pathogen recovery.

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157. Reducing Blood Culture Contamination Rates Through the Use of a Red Top Tube Discard

Open Forum Infectious Diseases ◽

10.1093/ofid/ofy209.027 ◽

2018 ◽

Vol 5 (suppl_1) ◽

pp. S12-S13

Author(s):

Bharat Ramlal ◽

Rosemary Renouf ◽

Jaber Aslanzadeh

Keyword(s):

Blood Culture ◽

Effective Means ◽

Accurate Determination ◽

Laboratory Diagnosis ◽

The United States ◽

Culture Collection ◽

Blood Cultures ◽

Contamination Rate ◽

Blood Contamination ◽

Blood Draw

Abstract Background Septicemia is a major cause of death in the United States and accounts for up to $16.7 billion in annual health care expenses. Blood culture is the gold standard for laboratory diagnosis of bacteremia and resultant septicemia; however, false-positive blood cultures hinder the accurate determination of true bacteremia with often serious implications. The goal of this study was to determine the efficacy of collecting a 1 mL discard in a red tube prior to blood culture collection and to assess its effectiveness in reducing contamination rates in Hartford Hospital Emergency Department (HHED). Methods During the months of June to December 2017 blood cultures were collected by the phlebotomy team using ChloraPrep (chlorhexidine) as the sole disinfecting agent. Blood cultures consisted of BD BACTEC plus Aerobic/F and BD BACTEC Lytic/10 Anaerobic drawn at the same time and monitored on BD BACTEC FX instrument for 5 days. Prior to collecting blood cultures 1 mL of blood was collected in a red top tube and discarded. Monthly and overall contamination rates were then compared with 2016 in which a red top discard tube was not used. Results During June to December 2016, there were a total of 9,576 blood cultures collected with a total of 178 contaminants and an overall contamination rate of 1.9%. During June to December 2017, there were a total of 9,133 blood cultures collected with a total of 73 contaminants and an overall contamination rate of 0.8%. During both years, our contamination rates were well below the CLSI recommendation; however, a significant reduction in blood culture contamination was observed after the use of a Red Top discard tube (0.8% vs. 1.9%) (Figures 1–3). Conclusion The cost of a standard blood draw with Red Top tubes is minimal (few cents) while a single collection using an initial specimen diversion device (ISDD) can range from $15 to $18. During the course of this study, the use of a standard Red Top discard cost approximately $456 (2017); if an ISDD was used instead, this would have generated $136,995 in healthcare cost. At our institution, we were able to keep our contamination rates below 1% after the implementation of a standard Red Top discard tube. This suggests that the use of a Red Top discard prior to blood culture collection is an effective means for reducing and maintaining a low blood contamination rate. Disclosures All authors: No reported disclosures.

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