Validating the IBIS plate reader for colorimetric bacterial identification at the mycobacteriology reference laboratory in Cotonou, Benin

Assays for bacterial identification use small wells with test reagents whose colour change are specific to a bacterial species. These are read by eye in most laboratories. The reading is subjective, particularly for borderline colours, and nothing of it is kept: once the species has been assigned, the strip is discarded. IBIS, a plate reader developed at ITM, photographs the galleries, scores each reaction automatically and stores the image, so that a reading can be reviewed afterwards.

From 23 July to 15 August 2026, Klaas Dewaele (PhD student, ITM) stayed at the Laboratoire de Référence des Mycobactéries (LRM) in Cotonou to install the reader and start a study of how well its readings agree with those of trained technicians.

The study prospectively includes Gram-negative isolates from blood cultures at the Centre National Hospitalier Universitaire (CNHU) in Cotonou, collected in weekly batches. This study includes several commercial colorimetric tests and assesses how the ITM reader results compare to those obtained by two independent technicians.

During the same stay, Ramata Balde, head technician of ITM’s Unit of Mycobacteriology, trained the LRM staff in broth microdilution – the reference method for drug susceptibility testing – both manually and using an Opentrons OT-2 pipetting robot installed for the purpose.

This staff mobility was supported by the Alliance for Education in Tropical Medicine and International Public Health, funded by the Belgian Directorate General for Development Cooperation and Humanitarian Aid (DGD).

Demonstration of the IBIS plate reader at LRM

Equipment

Mycobacteriology

Research skills

Sub-Saharan Africa

TB