Evaluation of MicroScan Bacterial Identification Panels for Low-Resource Settings

Abstract

Bacterial identification is challenging in low-resource settings (LRS). We evaluated the MicroScan identification panels (Beckman Coulter, Brea, CA, USA) as part of Médecins Sans Frontières’ Mini-lab Project. The MicroScan Dried Overnight Positive ID Type 3 (PID3) panels for Gram-positive organisms and Dried Overnight Negative ID Type 2 (NID2) panels for Gram-negative organisms were assessed with 367 clinical isolates from LRS. Robustness was studied by inoculating Gram-negative species on the Gram-positive panel and vice versa. The ease of use of the panels and readability of the instructions for use (IFU) were evaluated. Of species represented in the MicroScan database, 94.6% (185/195) of Gram-negative and 85.9% (110/128) of Gram-positive isolates were correctly identified up to species level. Of species not represented in the database (e.g., Streptococcus suis and Bacillus spp.)), 53.1% out of 49 isolates were incorrectly identified as non-related bacterial species. Testing of Gram-positive isolates on Gram-negative panels and vice versa (n = 144) resulted in incorrect identifications for 38.2% of tested isolates. The readability level of the IFU was considered too high for LRS. Inoculation of the panels was favorably evaluated, whereas the visual reading of the panels was considered error-prone. In conclusion, the accuracy of the MicroScan identification panels was excellent for Gram-negative species and good for Gram-positive species. Improvements in stability, robustness, and ease of use have been identified to assure adaptation to LRS constraints.

Paradigm Shift in Antimicrobial Resistance Pattern of Bacterial Isolates during the COVID-19 Pandemic

“…All cultures were read after 18 to 24 h of inoculation for bacterial growth. Bacterial isolates obtained were processed by the automated identification method using Microscan WalkAway (Beckman Coulter, CA, USA) [ 52 ].…”

Comparison of Zinc Concentrations in the Broth of Commercial Automated Susceptibility Testing Devices (Vitek 2, MicroScan, BD Phoenix, and Sensititre)

“…In contrast to the Vitek and MicroScan panels, the BD Phoenix (Becton, Dickinson and Company, Sparks, MD) ( 8 ) and Sensititre (Thermo Fisher, Waltham, MA) ( 9 ) panels contain only dehydrated antibiotics and require rehydration with liquid culture medium by the end user using manufacturer-supplied broth. Thus, samples (100 μL) from three manufacturer lots of BD Phoenix automated susceptibility testing (AST) broth (Becton, Dickinson and Company, Sparks, MD) and Sensititre (Thermo Scientific) caMHB with N -tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid (TES; Remel Inc. KS, USA) were obtained.…”

AMR in low-resource settings: Médecins Sans Frontières bridges surveillance gaps by developing a turnkey solution, the Mini-Lab

“…It was created by developing target products profiles, analyzing the marketplace, selecting technologies that would work in MSF settings, and working with manufacturers to suggest adaptations to existing products when technologies did not yet exist. Rigorous laboratory testing then occurred [30], [31] with validation from experts in academia, including a prototype field-test in an MSF burn hospital in Haiti in 2019-2020 (Figure 2).…”

“…The Mini-Lab sample workup includes five internationally certificated (CE-IVD or FDA) analytical components: Manual biphasic blood culture bottles (Autobio Diagnostics Co., Ltd -Zhengzhou, China), sealed pack sub-culture media (Biomed Diagnostics Co., Ltd, White City, USA), identification and AST microplates (Beckman Coulter Co., Ltd, Sacramento, USA) and other tests for orientation (Gram staining, catalase, oxydase, aminopeptidase). All are compact, ready-to-use , easy-to-read and interpret, and can sustain the growth of bacterial pathogens common to low-resource and tropical settings [30], [31]. These tests have a long shelf life (12-18 months) and can be stored at 4-25°C.…”

“…After analytical component evaluations in European laboratories performed satisfactorily [30], [31], the first Mini-Lab prototype was deployed and evaluated in the MSF Burn Centre (Drouillard) in Port au Prince, Haiti from July 2019-April 2020. Its use and robustness overall was evaluated there in field conditions.…”