Multilaboratory Evaluation of a Novel Lateral Flow Immunochromatographic Assay for Confirming Isolation of Mycobacterium bovis from Veterinary Diagnostic Specimens.

Abstract

A novel lateral flow immunochromatographic device (LFD) was evaluated in several veterinary diagnostic laboratories. It was confirmed to be specific forandcells. The performance of the novel LFD was assessed relative to the confirmatory tests routinely applied after culture (spoligotyping or quantitative PCR [qPCR]) in each laboratory; liquid (MGIT or BacT/Alert) and/or solid (Stonebrink, Coletsos, or Lowenstein-Jensen) cultures were tested. In comparison to spoligotyping of acid-fast-positive MGIT cultures, percent agreement between positive LFD and spoligotyping results was excellent in two United Kingdom laboratories (97.7 to 100%) but lower in the Spanish context (76%), where spoligotyping was applied to MGIT cultures previously confirmed to be positive forcomplex (MTBC) by qPCR. Certain spoligotypes ofandwere not detected by the LFD in Spanish MGIT cultures. Compared to qPCR confirmation, the agreement between positive LFD and qPCR results was 42.3% and 50% for BacT/Alert and MGIT liquid cultures, respectively, and for solid cultures, it ranged from 11.1 to 89.2%, depending on the solid medium employed (Coletsos, 11.1%; Lowenstein-Jensen, 55.6%; Stonebrinks, 89.2%). Correlation between the novel LFD and BD MGIT TBc Identification test results was excellent when 190 MGIT cultures were tested (= 0.9791;< 0.0001), with the added benefit thatwas differentiated from another MTBC species in one MGIT culture by the novel LFD. This multilaboratory evaluation demonstrated the novel LFD's potential utility as a rapid test to confirm isolation ofandfrom veterinary specimens following culture.