Rapid and visual detection of Lawsonia intracellularis via an RPA-CRISPR/Cas12a assay.

The swine industry faces a substantial economic threat from Lawsonia intracellularis (LI), the bacterium responsible for porcine proliferative enteropathy. Infection commonly presents with diarrhea and increased enterocyte proliferation in the ileum and colon, ultimately resulting in impaired growth performance in affected pigs. Effective management of porcine proliferative enteropathy requires timely and accurate diagnosis. The method provides significant advantages over existing detection techniques, offering enhanced sensitivity and high accuracy. The assay achieves detection within one hour, with no observed cross-reactivity against a panel of common swine pathogens. Results can be visually interpreted under blue light. Clinical validation using 123 samples demonstrated 100% concordance with qPCR results (14 positive and 109 negative). Characterized by simplicity, rapidity, and high sensitivity, the RPA-CRISPR/Cas12a method represents a novel solution for Lawsonia intracellularis detection.