lancet-header

Preprints with The Lancet is a collaboration between The Lancet Group of journals and SSRN to facilitate the open sharing of preprints for early engagement, community comment, and collaboration. Preprints available here are not Lancet publications or necessarily under review with a Lancet journal. These preprints are early-stage research papers that have not been peer-reviewed. The usual SSRN checks and a Lancet-specific check for appropriateness and transparency have been applied. The findings should not be used for clinical or public health decision-making or presented without highlighting these facts. For more information, please see the FAQs.

Biphasic Versus Monophasic Manual Blood Culture Bottles for Low-Resource Settings: An In-Depth in vitro Evaluation Using Simulated Blood Cultures

34 Pages Posted: 11 Feb 2021

See all articles by Sien Ombelet

Sien Ombelet

University of Antwerp - Department of Clinical Sciences

Alessandra Natale

Médecins Sans Frontières - Operational Centre Paris

Jean-Baptiste Ronat

Médecins Sans Frontières - Operational Centre Paris

Thomas Kesteman

Hospital of Tropical Diseases - Oxford University Clinical Research Unit

Olivier Vandenberg

Université Libre de Bruxelles (ULB) - Center for Environmental Health and Occupational Health

Jan Jacobs

University of Antwerp - Department of Clinical Sciences; Nazi Boni University - Institut Supérieur des Sciences de la Santé

Liselotte Hardy

Institute of Tropical Medicine - Department of Clinical Sciences

More...

Abstract

Introduction: Manual (visually read) blood culture bottles (BCB) are frequently used in low-resource settings (LRS) where automated alternatives are less suitable. Yet performance evaluations of these BCBs are lacking, especially in comparison to automated systems. We evaluated two manual BCB types (the Bi-State BCB, Autobio; visually read BacT/ALERT bottles, bioMérieux) and used BacT/ALERT BCB monitored in a BacT/ALERT automate as a reference method.

Methods: BCBs were spiked in triplicate with 177 clinical isolates representing pathogens frequently found in LRS (19 bacterial, 1 yeast species) for both adult and pediatric formulations. Growth in manual BCBs was evaluated by visually inspecting the broth, agar slant, and – for BacT/ALERT BCB – color change of the growth indicator. Blind subculture was conducted after overnight incubation (Day 1).

Results: Overall yield was 95·9% and 95·5% for Bi-State and manual BacT/ALERT respectively, versus 96·1% for the reference method. The lowest yield occurred for Neisseria meningitidis and Burkholderia cepacia (83·3% and 83·1%) and was consistent among the three BC systems. On Day 1, growth was detected in 90·7% and 75·0% of grown BCBs in Bi-State and BacT/ALERT respectively, versus 99·3% for the reference method. On Day 2 detection rates were 100%, 97·7% and 100% respectively. Among 1013 grown Bi-State BCBs, growth mostly co-occurred in broth and slant (81·7%). Sufficient colony growth on the slant to perform further tests was present in only 44·1% and 59·0% of biphasic bottles on Day 2 and Day 3 respectively. Blind subculture generated colonies on Day 2 for 99·7% grown Bi-State and 99·2% of manual BacT/ALERT bottles respectively.

Conclusion: In these in-vitro experiments, the yield and time-to-detection of manual BCBs were comparable to an automated system. Bi-State BCBs outperformed manual BacT/ALERT bottles, but the agar slant did not allow earlier detection nor earlier colony growth when compared to blind subculture on Day 1.

Funding Statement: This research was funded by Médecins Sans Frontières (Mini-Lab project). Médecins Sans Frontières participated in study design, interpretation and writing of the manuscript.

Declaration of Interests: None to declare.

Ethics Approval Statement: Leftover blood from blood bank volunteers was used under research contract (file number CM20180327A). Clinical strains were obtained from ITM travel clinic and microbiological surveillance studies (Surveillance of antimicrobial resistance among consecutive blood culture isolates in tropical settings, Institutional Review Board 613/08, Ethical Committee University Hospital of Antwerp 8/20/96).

Keywords: blood cultures, low-resource settings, biphasic bottles, bloodstream infection

Suggested Citation

Ombelet, Sien and Natale, Alessandra and Ronat, Jean-Baptiste and Kesteman, Thomas and Vandenberg, Olivier and Jacobs, Jan and Hardy, Liselotte, Biphasic Versus Monophasic Manual Blood Culture Bottles for Low-Resource Settings: An In-Depth in vitro Evaluation Using Simulated Blood Cultures. Available at SSRN: https://ssrn.com/abstract=3781655 or http://dx.doi.org/10.2139/ssrn.3781655

Sien Ombelet

University of Antwerp - Department of Clinical Sciences ( email )

Belgium

Alessandra Natale

Médecins Sans Frontières - Operational Centre Paris ( email )

Cape Town
South Africa

Jean-Baptiste Ronat

Médecins Sans Frontières - Operational Centre Paris

France

Thomas Kesteman

Hospital of Tropical Diseases - Oxford University Clinical Research Unit ( email )

Vietnam

Olivier Vandenberg

Université Libre de Bruxelles (ULB) - Center for Environmental Health and Occupational Health ( email )

CP 132 Av FD Roosevelt 50
Brussels, Brussels 1050
Belgium

Jan Jacobs

University of Antwerp - Department of Clinical Sciences

Belgium

Nazi Boni University - Institut Supérieur des Sciences de la Santé

Burkina Faso

Liselotte Hardy (Contact Author)

Institute of Tropical Medicine - Department of Clinical Sciences ( email )