Multiplex Lateral Flow Immunochromatographic Assay Is an Effective Method to Detect Carbapenemases in Non-Susceptible...

Objectives: This study evaluated the diagnostic performance of the lateral flow immunochromatographic assay (RESIST-ACINETO, Coris BioConcept) for the rapid detection of the major carbapenemases in Acinetobacter baumannii. Methods: Blood culture isolates collected between 2014 and 2024 with meropenem MIC ≥ 4 mg/L were retrieved, re-identified by MALDI-TOF MS, and susceptibility was confirmed by broth microdilution. Carbapenemase genes (bla_OXA-23, bla_OXA-40, bla_NDM) were detected using multiplex PCR, which served as the reference standard. All isolates were tested using the RESIST ACINETO assay, and diagnostic accuracy parameters were calculated. Results: A total of 114 isolates were recovered and confirmed as A. baumannii. Among 93 carbapenem-non-susceptible isolates, 97.8% (91/93) were correctly identified by the assay. The test showed 99.1% sensitivity and 99.1% specificity, with most positive results appearing within 3-10 min. Two discrepant results were observed (one false positive, one false negative), while all meropenem-susceptible isolates tested negative. Conclusions: The RESIST ACINETO assay provides rapid, accurate detection of carbapenemases in A. baumannii, significantly reducing turnaround time compared with conventional workflows. Its performance supports integration into routine diagnostics to enhance timely resistance confirmation and infection-control interventions.