Correlation between blood volume, culture sets, and detection rates in bloodstream infections
DOI:
https://doi.org/10.18203/2320-6012.ijrms20260610Keywords:
Blood culture, Time to positivity, Blood stream infection, Turnaround timeAbstract
Background: Blood culture remains the gold standard for diagnosing bloodstream infections (BSIs), with diagnostic yield influenced by variables such as blood volume, number of culture sets, and processing time. This study evaluates these factors and their impact on blood culture positivity rates using the BD BACTEC™ FX 40 system.
Methods: A cross-sectional prospective study (June–December 2024) analysed blood cultures using BD BACTEC™ FX 40, assessing volume, sets, time to positivity (TTP), and organisms from laboratory records via standard microbiological methods.
Results: A total of 2,016 blood cultures were processed, yielding an overall positivity rate of 28.67%. Cultures with adequate blood volume (≥8 ml per bottle) demonstrated significantly higher positivity rates compared to those with suboptimal volumes (p<0.05). The majority of cultures (59.5%) had a volume between 10-15 ml, which also corresponded to the highest proportion of early time to positivity (TTP <24 hours). Use of two or more culture sets notably increased detection rates. Gram-positive organisms were the predominant isolates, accounting for 48.79% of positive cultures, with Staphylococcus spp. being the most commonly identified. Turnaround time (TAT) for final reporting varied, with the highest proportion of positive cultures (30.97%) finalized within 24-48 hours.
Conclusions: Adequate blood volume and multiple culture set significantly improve diagnostic yield in blood culture testing. Timely processing and reporting are crucial for effective clinical management of BSIs. These findings underscore the importance of adherence to recommended guidelines for blood culture collection and processing.
Metrics
References
Kumar A, Roberts D, Wood KE, Light B, Parrillo JE, Sharma S, et al. Duration of hypotension before initiation of effective antimicrobial therapy is the critical determinant of survival in human septic shock. Crit Care Med. 2006;34(6):1589-96. DOI: https://doi.org/10.1097/01.CCM.0000217961.75225.E9
Elnoby AS, Nahla R. The Clinical Utility and Stewardship Challenges of Time to Blood Culture Positivity. Hospital Pharmacy. 2025;61(1):15-9. DOI: https://doi.org/10.1177/00185787251364488
Cockerill FR, Wilson JW, Vetter EA, Goodman KM, Torgerson CA, Harmsen WS, et al. Optimal testing parameters for blood cultures. Clin Infect Dis. 2004;38(12):1724-30. DOI: https://doi.org/10.1086/421087
Hall KK, Lyman JA. Updated review of blood culture contamination. Clin Microbiol Rev. 2006;19(4):788-802. DOI: https://doi.org/10.1128/CMR.00062-05
Lowbury EJ, Kidson A, Lilly HA. A new selective blood agar medium for Streptococcus pyogenes and other haemolytic streptococci. J Clin Pathol. 1964;17(3):231-5. DOI: https://doi.org/10.1136/jcp.17.3.231
Lee A, Mirrett S, Reller LB, Weinstein MP. Detection of bloodstream infections in adults: how many blood cultures are needed?. J Clin Microbiol. 2007;45(11):3546-8. DOI: https://doi.org/10.1128/JCM.01555-07
Khare R, Kothari T, Castagnaro J, Hemmings B, Tso M, Juretschko S. Active monitoring and feedback to improve blood culture fill volumes and positivity across a large integrated health system. Clin Infect Dis. 2020;70(2):262-8. DOI: https://doi.org/10.1093/cid/ciz198
Timbrook TT, Morton JB, McConeghy KW, Caffrey AR, Mylonakis E, LaPlante KL. The effect of molecular rapid diagnostic testing on clinical outcomes in bloodstream infections: a systematic review and meta-analysis. Clin Infect Dis. 2017;64(1):15-23. DOI: https://doi.org/10.1093/cid/ciw649
Banerjee R, Teng CB, Cunningham SA, Ihde SM, Steckelberg JM, Moriarty JP, et al. Randomized trial of rapid multiplex polymerase chain reaction–based blood culture identification and susceptibility testing. Clin Infect Dis. 2015;61(7):1071-80. DOI: https://doi.org/10.1093/cid/civ447
Henning C, Aygül N, Dinnétz P, Wallgren K, Özenci V. Detailed analysis of the characteristics of sample volume in blood culture bottles. J Clin Microbiol. 2019;57(8):e00268-19. DOI: https://doi.org/10.1128/JCM.00268-19
Clinical and Laboratory Standards Institute (CLSI). Principles and Procedures for Blood Cultures; Approved Guideline. CLSI Document M47-A. Wayne, PA: CLSI; 2007. Available at: https://clsi.org/shop/standards/m47/?utm_source=chatgpt.com. Accessed on 29 March 2025.
Miller JM, Binnicker MJ, Campbell S, Carroll KC, Chapin KC, Gilligan PH, et al. A guide to utilization of the microbiology laboratory for diagnosis of infectious diseases: 2018 update. Clin Infect Dis. 2018;67(6):e1-94. DOI: https://doi.org/10.1093/cid/ciy381
Weinstein MP, Reller LB, Murphy JR, Lichtenstein KA. The clinical significance of positive blood cultures: a comprehensive analysis of 500 episodes of bacteremia and fungemia in adults. I. Laboratory and epidemiologic observations. Rev Infect Dis. 1983;5(1):35-53. DOI: https://doi.org/10.1093/clinids/5.1.35
Riedel S, Carroll KC. Blood cultures: key elements for best practices and future directions. J Infect Chemother. 2010;16(5):30116. DOI: https://doi.org/10.1007/s10156-010-0069-1
Kellogg JA, Manzella JP, McConville JH. Clinical correlation of quantitative pediatric blood cultures. J Clin Microbiol. 2000;38(6):2181-5. DOI: https://doi.org/10.1128/JCM.38.6.2181-2185.2000
Lamy B, Dargère S, Arendrup MC, Parienti JJ, attevin P. How to optimize the use of blood cultures for the diagnosis of bloodstream infections? A state-of-the-art. Front Microbiol. 2016;7:697. DOI: https://doi.org/10.3389/fmicb.2016.00697
Becker K, Heilmann C, Peters G. Coagulase-negative staphylococci. Clin Microbiol Rev. 2014;27(4):870-926. DOI: https://doi.org/10.1128/CMR.00109-13
Goto M, Al-Hasan MN. Overall burden of bloodstream infection and nosocomial bloodstream infection in North America and Europe. Clin Microbiol Infect. 2013;19(6):501-9. DOI: https://doi.org/10.1111/1469-0691.12195
Clerc O, Greub G. Routine use of point-of-care tests: usefulness and application in clinical microbiology. Clin Microbiol Infect. 2010;16(8):1054-61. DOI: https://doi.org/10.1111/j.1469-0691.2010.03281.x
Downloads
Published
How to Cite
Issue
Section
