Rapid and visually interpretable LAMP assay for detection of pathogenic Pseudomonas aeruginosa in artificial sputum

Area of Science:

• Microbiology
• Molecular Diagnostics
• Infectious Diseases

Background:

• Pseudomonas aeruginosa is a common pathogen causing severe lower respiratory tract infections.
• Rapid and visual detection of P. aeruginosa in sputum is crucial for timely treatment.
• The oprM gene is essential for the MexAB-OprM and MexXY-OprM efflux pumps in P. aeruginosa.

Purpose of the Study:

• To develop and evaluate a loop-mediated isothermal amplification (LAMP) assay for rapid detection of P. aeruginosa.
• To target the oprM gene for specific identification of P. aeruginosa.
• To assess the assay's efficiency, specificity, sensitivity, and limit of detection.

Main Methods:

• Development of a loop-mediated isothermal amplification (LAMP) assay targeting the oprM gene.
• Optimization of reaction temperature and amplification time.
• Evaluation using artificial sputum samples spiked with P. aeruginosa and comparison with PCR.
• Testing specificity against other bacterial strains and validation with clinical isolates.

Main Results:

• The LAMP assay demonstrated higher efficiency than PCR and no interference in artificial sputum.
• The assay showed selective detection of P. aeruginosa, differentiating it from other sputum bacteria.
• The analytical limit of detection (LOD) was 2 CFU/mL.
• Validation confirmed high specificity and sensitivity, indicating potential for detecting antibiotic resistance.

Conclusions:

• The oprM gene-targeted LAMP assay provides rapid, sensitive, and specific detection of P. aeruginosa in artificial sputum.
• The assay's low detection limit allows reliable differentiation from other respiratory bacteria.
• This LAMP assay is a promising diagnostic tool for early P. aeruginosa infection detection.