METHOD FOR OBTAINING BLOOD CULTURE WHILE DIAGNOSING BLOODSTREAM INFECTION

Diagnosing of bloodstream infection (BSI) in outpatients is essential. A large blood volume is required to obtain blood culture (CLSI): 2 sets, 40ml of blood for diagnosing in 95% cases of bacteremia. Molecular-genetic methods can not replace blood culture method, but they accelerate the identification of any pathogen. Culturomics gives a combination of different conditions for isolating microorganisms from a sample and along with their genetic identification. We used the patent method for direct inoculation of buffy-coat from 4,5ml of a venous blood sample and MALDI-ToF identification method. In 382 outpatients examined there were received 183 blood cultures (48,0%), more often among women (65,6%) and young people (74,9%). The causative agents of community-acquired bloodstream infection were aerobes (73,4%), anaerobes (24,2%), fungi (2,4%). The gram-positive cocci were prevailing (51,4%) and the gram-negative rods were isolated rather seldom (9,6%). BSI was monomicrobial (66,5%) and polymicrobial (33,5%). Polymicrobial blood cultures had 2, 3, 4 agents in one blood sample (75,4%, 18,8%, 5,8%, respectively). There were also found combinations of different species of aerobes (47,8%), aerobes with anaerobes (42%). BSI caused complications of the primary disease of the respiratory system, urogenital system and in 100% of cases after plastic surgery. A small blood volume is required for buffy-coat inoculation, the direct agar culture reduces the response time to 2 days, so it makes genetic identification possible on the 2nd day from the moment of blood collection.

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1341. Blood Volume Collected for Blood Cultures in Infants with Suspected Neonatal Sepsis in the NICU

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.1523 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S682-S682

Author(s):

Maria S Rueda Altez ◽

Lamia Soghier ◽

Joseph M Campos ◽

James Bost ◽

Jiaxiang Gai ◽

...

Keyword(s):

Bloodstream Infection ◽

Blood Volume ◽

Bloodstream Infections ◽

Blood Cultures ◽

Categorical Variables ◽

Continuous Variables ◽

Volume Calculation ◽

Culture Negative ◽

Time Of Collection ◽

Rule Out

Abstract Background Blood cultures have high sensitivity to detect bacteremia in septic neonates when >=1 ml of blood is collected. Neonatologists often cite low confidence in microbiologic sampling as rationale for continuing antibiotics without a focus of infection despite negative blood cultures, resulting in prolonged antimicrobial therapy. We aim to describe the blood culture sample volumes in NICU patients, to identify factors associated with sample volumes < 1ml, and to compare the sample volumes of patients treated for culture-negative sepsis with those with bloodstream infections and those treated for a ≤72-hour sepsis rule-out Methods Data from this observational cohort study were collected retrospectively and prospectively from NICU patients with blood cultures obtained from September 2018 to February 2019. Clinical data were collected through chart review. All inoculated culture bottles were weighed for volume calculation. We determined the association of age, weight, sample source, and time of collection with volume < 1mL. Continuous variables were analyzed using Wilcoxon-Mann-Whitney, and categorical variables using chi-squared test. For aim 3, the volumes of the groups were compared using analysis of variance. Results A total of 310 blood cultures were identified, corresponding to 159 patients. Of these, 49 (16%) were positive. Among the negative blood cultures, 86% were collected in patients who subsequently received antibiotics (Figure 1). Median inoculated volume was 0.6 ml (IQR: 0.1-2.4). Weight and age at time of culture collection, source of sample, and time of collection were not significantly associated with the inoculation of < 1ml of blood. Median volume of blood was 0.6ml (0.3-0.6) for sepsis rule-out, 0.6ml (0.2-0.6) for bloodstream infection, and 0.6ml (0.6-1.4) for culture-negative sepsis. No difference was found among the three groups (p=0.54) Figure 1. Classification of blood cultures identified during study period Conclusion The blood volume collected for cultures in the NICU is lower than recommended. Clinical and environmental characteristics are not significantly associated with the inoculated volume. The volume of blood sampled does not differ in patients with culture-negative sepsis, bloodstream infection and sepsis rule-out, and should not be a justification for longer duration of antibiotic therapy Disclosures All Authors: No reported disclosures

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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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Rapid Diagnosis of Bacteremia in Adults Using Acridine Orange Stained Buffy Coat Smears

Canadian Journal of Infectious Diseases ◽

10.1155/1990/159215 ◽

1990 ◽

Vol 1 (1) ◽

pp. 7-10

Author(s):

Mark Miller ◽

Jack Mendelson

Keyword(s):

Blood Culture ◽

Acridine Orange ◽

Buffy Coat ◽

Blood Cultures ◽

Rapid Screening ◽

Blood Culture System ◽

Blood Samples ◽

Significant Difference ◽

Rapid Screening Test ◽

Low Sensitivity

The use of acridine orange stained buffy coat smears was assessed as a rapid screening test for bacteremia in adults. A total of 356 consecutive blood cultures were submitted with simultaneous anticoagulated blood samples, from which a buffy coat smear was prepared and stained with acridine orange (100 mg/L; pH 3.0). Forty-one of 356 blood samples (12%) yielded organisms in the blood culture system. Compared to blood culture, the overall sensitivity of acridine orange stained buffy coat smears was 16%, specificity 88%, and positive predictive value 13%. There was no statistically significant difference in performance of the test among patients who had fever greater than 39°C and/or shock. The low sensitivity and specificity of the test makes it unsuitable as a means of rapid screening for adults with suspected bacteremia.

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1148. Reduction of Blood Culture Contamination Rates by an Altered Sampling Protocol: Single-Center, Prospective, Randomized, Controlled, Open-Label Trial

Open Forum Infectious Diseases ◽

10.1093/ofid/ofy210.981 ◽

2018 ◽

Vol 5 (suppl_1) ◽

pp. S345-S345

Author(s):

Jacob Strahilevitz ◽

Or Svinik ◽

Alon Lalezari ◽

Odaya Tel-Zur ◽

Shlomo Sinvani ◽

...

Keyword(s):

Blood Culture ◽

Standard Method ◽

Standard Procedure ◽

Real Life ◽

Medical Personnel ◽

Blood Chemistry ◽

Test Tube ◽

Blood Cultures ◽

Blood Collection ◽

Open Label

Abstract Background Contaminated blood cultures remain a challenge for patients, physicians, and microbiology laboratories, often leading to unnecessary antibiotic treatment. One approach to reduce contamination is to avoid culturing the initial blood sample that can contain a contaminated plug of skin from the needle stick. Initial specimen diversion technique (ISDT) was associated with decreased rate of blood culture contamination, when applied by trained phlebotomists, using either sterile vacuum blood collection tubes or a designated device. The aim of this study was to test ISDT in real-life, using externally nonsterile regular vacuum sample tubes for the diversion, by any medical personnel taking blood cultures. Methods Adults from whom the treating physician planned to take blood cultures and additional blood chemistry tests, in the same venous puncture, were eligible and were randomly assigned to intervention or control arms. The hospital’s standard procedure for blood drawing was maintained, except that in the intervention arm, blood was aspirated to a green-capped tube, which was used for regular biochemistry tests, prior to the blood culture. Results Four hundred twenty-three blood cultures were obtained from 404 patients. Of 404 (11.1%) of the blood cultures, 45 yielded microbial growth, with 31 (7.7%) regarded as true pathogens and 14 (3.5%) as contaminants. Detection of true bloodstream infection was similar by the two methods, 16/181 (8.83%) with the ISDT, and 15/223 (6.72%) using the standard method. The ISDT was associated with a significantly less isolation of presumed contaminants compared with the standard method, 2/165 (1.2%) vs. 12/208 (5.76%), P = 0.02. Conclusion ISDT, by any medical personnel, through altered order of test tube vs. blood culture sampling significantly reduced contamination of blood cultures without loss of diverted blood. Disclosures All authors: No reported disclosures.

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Obtaining Blood Cultures by Venipuncture versus from Central Lines Impact on Blood Culture Contamination Rates and Potential Effect on Central Line–Associated Bloodstream Infection Reporting

Infection Control and Hospital Epidemiology ◽

10.1086/673142 ◽

2013 ◽

Vol 34 (10) ◽

pp. 1042-1047 ◽

Cited By ~ 26

Author(s):

John M. Boyce ◽

Jacqueline Nadeau ◽

Diane Dumigan ◽

Debra Miller ◽

Cindy Dubowsky ◽

...

Keyword(s):

Blood Culture ◽

Bloodstream Infection ◽

Hospital Costs ◽

Cost Savings ◽

Central Line ◽

Potential Effect ◽

Blood Cultures ◽

Blood Samples ◽

Central Lines ◽

Contaminated Blood

Objective.Reduce the frequency of contaminated blood cultures that meet National Healthcare Safety Network definitions for a central line-associated bloodstream infection (CLABSI).Design.An observational study.Setting.A 500-bed university-affiliated hospital.Methods.A new blood culture policy discouraged drawing blood samples from central lines. Phlebotomists were reeducated regarding aseptic technique when obtaining blood samples by venipuncture. The intravenous therapy team was taught how to draw blood samples by venipuncture and served as a backup when phlebotomists were unable to obtain blood samples. A 2-nurse protocol and a special supply kit for obtaining blood samples from catheters were developed. Rates of blood culture contamination were monitored by the microbiology laboratory.Results.The proportion of blood samples obtained for culture from central lines decreased from 10.9% during January–June 2010 to 0.4% during July–December 2012 (P< .001). The proportion of blood cultures that were contaminated decreased from 84 (1.6%) of 5,274 during January–June 2010 to 21 (0.5%) of 4,245 during January–June 2012 (P< .001). Based on estimated excess hospital costs of $3,000 per contaminated blood culture, the reduction in blood culture contaminants yielded an estimated annualized savings of $378,000 in 2012 when compared to 2010. In mid-2010, 3 (30%) of 10 reported CLABSIs were suspected to represent blood culture contamination compared with none of 6 CLABSIs reported from mid-November 2010 through June 2012 (P= 0.25).Conclusions.Multiple interventions resulted in a reduction in blood culture contamination rates and substantial cost savings to the hospital, and they may have reduced the number of reportable CLABSIs.

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Regression Discontinuity of Blood Culture Contamination Rate After Changing of Disinfectants: Retrospective Observational Study

10.21203/rs.3.rs-754189/v1 ◽

2021 ◽

Author(s):

Koshi Ota ◽

Daisuke Nishioka ◽

Yuri Ito ◽

Emi Hamada ◽

Naomi Mori ◽

...

Keyword(s):

Emergency Department ◽

Blood Culture ◽

Observational Study ◽

Regression Discontinuity ◽

Blood Cultures ◽

University Hospital ◽

Retrospective Observational Study ◽

Contamination Rate ◽

Blood Collection ◽

Contaminated Blood

Abstract Background: Blood cultures are indispensable for detecting life-threatening bacteremia. Little is known about associations between contamination rates and topical disinfectants for blood collection in adults.Objective: We sought to determine whether a change in topical disinfectants was associated with the rates of contaminated blood cultures in the emergency department of a single institution.Methods: This single-center, retrospective observational study of consecutive patients aged 20 years or older was conducted in the emergency department (ED) of a university hospital in Japan between August 1, 2018 and September 30, 2020. Pairs of blood samples were collected for aerobic and anaerobic culture from the patients in the ED. Physicians selected topical disinfectants according to their personal preference before September 1, 2019; alcohol/chlorhexidine gluconate (ACHX) was mandatory thereafter, unless the patient was allergic to alcohol. Regression discontinuity analysis was used to detect the effect of the mandatory usage of ACHX on rates of contaminated blood cultures.Results: We collected 2,141 blood culture samples from 1097 patients and found 164 (7.7%) potentially contaminated blood cultures. Among these, 445 (20.8%) were true bacteremia and 1,532 (71.6%) were true negatives. Puncture site disinfection was performed with ACHX for 1,345 (62.8%) cases and with povidone-iodine (PVI) for 767 (35.8%) cases. The regression discontinuity analysis showed that mandatory ACHX usage significantly reduced the blood culture contamination rate by 9.6% (95% confidence interval (CI): 5.0%–14.2%, P <0.001).Conclusion: Rates of contaminated blood cultures were significantly lower when ACHX was used as the topical disinfectant.

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Does concomitant bacteraemia hide the fungi in blood cultures? An in vitro study

Journal of Medical Microbiology ◽

10.1099/jmm.0.001210 ◽

2020 ◽

Vol 69 (7) ◽

pp. 944-948

Author(s):

Yasemin Oz ◽

Sukran Onder ◽

Ekin Alpaslan ◽

Gul Durmaz

Keyword(s):

Blood Culture ◽

Bloodstream Infection ◽

Microscopic Examination ◽

Type Species ◽

Blood Cultures ◽

Specific Patient ◽

Content Type ◽

Link Type ◽

Direct Microscopic Examination ◽

Positive Direct

Introduction. Polymicrobial infections including yeasts and bacteria are not rare and patients with polymicrobial bloodstream infection have higher early and overall case fatality rates. The diagnosis of invasive fungal and bacterial infections is mainly based on blood culture. Aim. The aim was to reveal the effect of concomitant bacteraemia on the detection of fungi from blood cultures in the presence of polymicrobial bloodstream infections involving Candida and non-Candida fungi and to show the superiority of blood culture bottles including selective fungal media in such situations. Methodology. Twenty-four polymicrobial bloodstream infection models – involving one fungus and one bacterium – were constituted by using clinical blood culture isolates ( Escherichia coli , Staphylococcus aureus , Pseudomonas aeruginosa , Candida albicans, Candida glabrata, Fusarium solani and Trichosporon asahii). The Plus Aerobic/F (PAF) and Mycosis IC/F (MICF) culture bottles were used with the BACTEC 9240 device. After a bottle signalled positive, direct microscopic examination and subcultures on agar plates were performed. Results. All of fungi that were inoculated alone and in combination were detected by both direct microscopic examination and subcultures on agar plates from MICF bottles, whereas direct microscopic examination only revealed the bacterial agents from PAF bottles including combinations. Furthermore, fungal growth was hidden by bacterial growth on blood agar subcultures from PAF bottles including combinations of F. solani, C. glabrata or T. asahii with bacteria. Conclusion. Blood culture bottles including selective fungal media that can allow selective growth of fungi and earlier detection of some species should be preferred in addition to non-selective blood culture bottles, especially in specific patient populations. Further, the use of selective agar plates such as inhibitory mould agar may contribute to the solution of this problem in clinical laboratories.

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Education and coaching to optimise blood culture volumes: continuous quality improvement in microbiology

BMJ Open Quality ◽

10.1136/bmjoq-2017-000228 ◽

2018 ◽

Vol 7 (3) ◽

pp. e000228

Author(s):

Claudia R Libertin ◽

Keith A Sacco ◽

Joy H Peterson

Keyword(s):

Quality Improvement ◽

Blood Culture ◽

Blood Volume ◽

Continuous Quality Improvement ◽

Blood Cultures ◽

Aerobic Culture ◽

Continuous Quality ◽

Fill Volume ◽

Major Variable ◽

Improvement Programme

The blood volume cultured in the detection of bacteraemia is a major variable in treating patients with systemic inflammatory response syndrome. The fact that drawing optimal volumes (8–10 mL) of blood for culture increases the sensitivity of the method is well established. This study aimed to optimise the mean blood volumes (mBVs) to that recommended level in a small rural hospital by implementing a continuous quality improvement programme in clinical microbiology. The education of phlebotomists, followed by monthly feedback and coaching sessions, can influence the blood volume drawn by phlebotomists and improve the sensitivity of blood cultures. Statistically significant increase (p<0.001) in both mBVs and median blood culture volumes occurred within 5 months compared with the baseline values obtained in the preceding 10 months. This quality improvement was sustained over 1 year. The mBVs inoculated into aerobic culture bottles met the manufacturer’s instructions of a fill volume of 8 to 10 mL of blood per bottle and optimised the yield of isolation of organisms from blood cultures.

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Rapid Rule Out of Culture-Negative Bloodstream Infections by Use of a Novel Approach to Universal Detection of Bacteria and Fungi

The Journal of Applied Laboratory Medicine ◽

10.1373/jalm.2018.027706 ◽

2019 ◽

Vol 3 (4) ◽

pp. 534-544 ◽

Cited By ~ 1

Author(s):

Andrew J Rogers ◽

Daniel S Lockhart ◽

Rebecca Clarke ◽

Helen V Bennett ◽

Yassar Kadoom ◽

...

Keyword(s):

Blood Culture ◽

Bloodstream Infection ◽

Bloodstream Infections ◽

Blood Cultures ◽

Culture Bottle ◽

Detection Range ◽

Overnight Incubation ◽

Number Of Patients ◽

Bacteria And Fungi ◽

Rule Out

Abstract Background Currently it can take up to 5 days to rule out bloodstream infection. With the low yield of blood cultures (approximately 10%), a significant number of patients are potentially exposed to inappropriate therapy that can lead to adverse events. More rapid rule out can accelerate deescalation or cessation of antimicrobial therapy, improving patient outcomes. Methods A method is described, termed enzymatic template generation and amplification (ETGA), that universally and sensitively detects DNA polymerase activity liberated from viable bacteria and fungi isolated from blood culture samples as a measure of bloodstream infection. ETGA was applied in a diagnostic test format to identify negative blood cultures after an overnight incubation. Performance data for a prototype (Cognitor) and automated (Magnitor) version of the test are presented. Results The Cognitor manual assay displayed analytical reactivity for a panel of the 20 most prevalent causes of bloodstream infection, with a detection range of 28–9050 CFU/mL. Validation with 1457 clinical blood cultures showed a negative predictive value of 99.0% compared to blood culture incubation for 5 days. Magnitor showed an improved detection range of 1–67 CFU/mL, allowing for detection of bacteria-supplemented blood cultures after 2–8 h incubation, and Candida albicans-supplemented blood cultures at 16–22 h, 5–15 h faster than blood culture. Removing an aliquot from a blood culture bottle and replacing the bottle into the incubator was shown not to result in contaminating organisms being introduced. Conclusions The described method displays excellent breadth and detection for microbial cells and demonstrates the capability of confirming negative blood cultures after an overnight incubation in a blood culture instrument.

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Delaying the Empiric Treatment of Candida Bloodstream Infection until Positive Blood Culture Results Are Obtained: a Potential Risk Factor for Hospital Mortality

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.9.3640-3645.2005 ◽

2005 ◽

Vol 49 (9) ◽

pp. 3640-3645 ◽

Cited By ~ 856

Author(s):

Matthew Morrell ◽

Victoria J. Fraser ◽

Marin H. Kollef

Keyword(s):

Blood Culture ◽

Hospital Mortality ◽

Blood Sample ◽

Bloodstream Infection ◽

Cohort Analysis ◽

Multiple Logistic Regression Analysis ◽

Bloodstream Infections ◽

Diagnostic Techniques ◽

Antifungal Treatment ◽

Delayed Treatment

ABSTRACT Fungal bloodstream infections are associated with significant patient mortality and health care costs. Nevertheless, the relationship between a delay of the initial empiric antifungal treatment until blood culture results are known and the clinical outcome is not well established. A retrospective cohort analysis with automated patient medical records and the pharmacy database at Barnes-Jewish Hospital was conducted. One hundred fifty-seven patients with a Candida bloodstream infection were identified over a 4-year period (January 2001 through December 2004). Fifty (31.8%) patients died during hospitalization. One hundred thirty-four patients had empiric antifungal treatment begun after the results of fungal cultures were known. From the time that the first blood sample for culture that was positive was drawn, 9 (5.7%) patients received antifungal treatment within 12 h, 10 (6.4%) patients received antifungal treatment between 12 and 24 h, 86 (54.8%) patients received antifungal treatment between 24 and 48 h, and 52 (33.1%) patients received antifungal treatment after 48 h. Multiple logistic regression analysis identified Acute Physiology and Chronic Health Evaluation II scores (one-point increments) (adjusted odds ratio [AOR], 1.24; 95% confidence interval [CI], 1.18 to 1.31; P < 0.001), prior antibiotic treatment (AOR, 4.05; 95% CI, 2.14 to 7.65; P = 0.028), and administration of antifungal treatment 12 h after having the first positive blood sample for culture (AOR, 2.09; 95% CI, 1.53 to 2.84; P = 0.018) as independent determinants of hospital mortality. Administration of empiric antifungal treatment 12 h after a positive blood sample for culture is drawn is common among patients with Candida bloodstream infections and is associated with greater hospital mortality. Delayed treatment of Candida bloodstream infections could be minimized by the development of more rapid diagnostic techniques for the identification of Candida bloodstream infections. Alternatively, increased use of empiric antifungal treatment in selected patients at high risk for fungal bloodstream infection could also reduce delays in treatment.

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