Diagnostic Evaluation Study of the BactInsight Blood Culture System in West-Africa (SIMBLE-FIELD)

Diagnosis of bloodstream infections (BSI) is done by sampling blood in blood culture bottles that are checked for growth in the microbiology laboratory. In LRS, microbiology laboratories are however scarce, and BSI cannot be diagnosed, resulting in overuse of antibiotics which fuels AMR. For diagnosis of BSI, so-called manual blood culture (equipment-free) systems are used in LRS, with daily visual inspection for growth. Compared to automates, manual systems are less sensitive, and growth is slower; in addition, training and experience are needed before laboratory staff is competent to detect growth when inspecting the blood culture bottles.

A simplified blood culture system could enable expanded use of blood cultures in LRS and would thus improve BSI treatment. Ongoing research at the Institute of Tropical Medicine, in collaboration with Ghent University has resulted in a novel, simple, cheap, open-access and robust blood culture system, the Bactinsight blood culture system. This system consists of two modules. Firstly, a portable, battery-operated measurement device (turbidimeter), which monitors and detects bacterial growth in blood culture bottles based on the turbidity of the culture medium caused by bacterial growth. Secondly, optimized blood culture bottles have been developed. A second step in blood cultures is the identification of the causing organism. Researchers at LETI (Grenoble, France) have developed a lensfree microscope, which simplifies and expedites identification of the causative organisms, improving patient's diagnosis and more directed antibiotic treatment. The lensfree microscope is an additional module for the Bactinsight blood culture system.

In SIMBLE, the Bactinsight blood culture system will be evaluated against reference systems in two phases. During the optimization phase in Belgium, the performance of Bactinsight turbidimeter + lensfree microscope will be tested in a reference hospital laboratory. In parallel, an in vitro laboratory evaluation of the Bactinsight blood culture system (turbidimeter + blood culture bottles + lensfree microscope) will be done using spiked blood cultures. In the field-testing phase, the ease-of-use, acceptability, adoptability and performance of Bactinsight blood culture system will be evaluated in three hospitals in Benin and Burkina Faso. The blood culture bottles used for this study will be manufactured in a production facility in Benin, that will be installed at the start of the project.

Study Overview

• Status: Completed
• Conditions: Bacterial Infections
• Intervention / Treatment: Diagnostic test: BactInsight blood culture system

• Study Type: Observational
• Enrollment (Actual): 1724

Contacts and Locations

Study Locations

• Benin
  • Boko, Benin
    • Hôpital Saint Jean de Dieu de Boko
  • Cotonou, Benin
    • Centre National Hospitalier et Universitaire Hubert Koutoukou MAGA

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 15 years and older (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Patients older then 15 years old presenting themselves with indications for blood culture sampling and for whom collection of a blood culture sample is part of standard clinical practice.

Description

Inclusion Criteria:

• With indications for blood culture sampling and for whom collection of a blood culture sample is part of standard clinical practice
• Willing and able to provide written informed consent (assent for minors)

Exclusion Criteria:

• none

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
CNHU-HKM; BactInsight system compared to BacT/ALERT® 3D	Diagnostic test: BactInsight blood culture system; A battery-operated measurement device (turbidimeter), which monitors and detects bacterial growth in blood culture bottles based on the turbidity of the culture medium caused by bacterial growth, in combination with optimized blood culture bottles.
Hôpital Saint Jean de Dieu, Boko; BactInsight system compared to manual blood culture system (visual inspection)	Diagnostic test: BactInsight blood culture system; A battery-operated measurement device (turbidimeter), which monitors and detects bacterial growth in blood culture bottles based on the turbidity of the culture medium caused by bacterial growth, in combination with optimized blood culture bottles.
Centre Hospitalier Universitaire Yalgado Ouédraogo; BactInsight system compared to BacTec FX40	Diagnostic test: BactInsight blood culture system; A battery-operated measurement device (turbidimeter), which monitors and detects bacterial growth in blood culture bottles based on the turbidity of the culture medium caused by bacterial growth, in combination with optimized blood culture bottles.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time-to-actionable result	The paired Wilcoxon signed rank test will be used to compare the location of the distribution of time-to-actionable result measurements between the two groups for those with a positive blood culture result.; BactInsight versus manual system: Time-to-actionable result is compared between both groups with the Wilcoxon signed rank test at the 5% significance level.; BactInsight versus automated system: The non-inferiority margin equals 12 hours. Non-inferiority is shown if the upper limit of the two-sided 95% confidence interval for the median of the differences from the Wilcoxon signed rank test is lower than 12h i.e. 12 is excluded from the non-parametric confidence interval.	Within 8 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time-to-detection	The paired Wilcoxon signed rank test will be used to compare the location of the distribution of time-to-detection measurements between the two groups for those with a positive blood culture result.	Within 8 days
Yield	The McNemar's test will be used to compare the yield between the BactInsight system and the manual reference system at the 5% significance level in order to detect if there is a statistically significant difference between the paired binary data in terms of proportions. o The difference in yield between the BactInsight system and the automated system will be compared to a non-inferiority margin of 15%. Non-inferiority is shown if the lower limit of the two-sided 95% confidence interval is larger than -0.15 i.e. if -0.15 is excluded from the confidence interval. A non-inferiority margin of 15% was chosen as reasonable based on clinical and practical arguments.	2 years
Diagnostic performance	Sensitivity and specificity will be calculated for the BactInsight system compared to the composite reference standard, based on the combined result from the components tests i.e. the BactInsight and reference system in use.	2 years

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Yield - Antibiotic use	Test whether yield differs in case of antibiotic use (yes/no) within 48 hours prior to blood culture sampling: Pearson Chi-square test (or Fisher exact test in case of small sample size).	2 years
Yield - V blood sampled	Test whether yield differs with different volumes of blood sampled (e.g. 5-8 ml; 8-10 ml; 10-15 ml): Pearson Chi-square test (or Fisher exact test in case of small sample size).	2 years

Collaborators and Investigators

• Sponsor: Institute of Tropical Medicine, Belgium
• Collaborators: University Ghent; European and Developing Countries Clinical Trials Partnership (EDCTP); Commissariat A L'energie Atomique; Université Libre de Bruxelles; Reactivos para Diagnóstico, S.L.; Centre Hospitalier Universitaire Yalgado Ouédraogo; Centre National Hospitalier et Universitaire de Pneumo-Phtisiologie de Cotonou
• Investigators: Principal Investigator: Barbara Barbé, Instituut voor Tropische Geneeskunde

Study record dates

Study Major Dates

• Study Start (Actual): June 8, 2023
• Primary Completion (Actual): May 8, 2025
• Study Completion (Actual): September 1, 2025

Study Registration Dates

• First Submitted: February 1, 2023
• First Submitted That Met QC Criteria: February 1, 2023
• First Posted (Actual): February 10, 2023

Study Record Updates

• Last Update Posted (Estimated): December 9, 2025
• Last Update Submitted That Met QC Criteria: December 2, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: diagnostics; blood culture
• Additional Relevant MeSH Terms: Infections; Bacterial Infections and Mycoses; Bacterial Infections
• Other Study ID Numbers: SIMBLE-FIELD

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• product manufactured in and exported from the U.S.: No