Abstract / Summary
Background: Environmental contamination of hospital surfaces, especially in high-risk clinical areas, partly sustains healthcare-associated infections. The detection of microbiological contamination in hospital settings using culture-based methods remains fundamental, even though these methods are not rapid, show moderate sensitivity in areas with low microbial loads, and are unsuitable for some microbial species. This multicentre study evaluated the performance of loop-mediated isothermal amplification (LAMP) for the rapid detection of major nosocomial pathogens on hospital surfaces. Methods: A multicentre observational method–comparison study was conducted in three Italian hospital centres. Overall, 298 environmental surface samples were collected from clinical areas included in local infection-prevention monitoring plans. For each sampling point, LAMP swab sampling was paired with an adjacent contact plate culture. LAMP assays targeted Staphylococcus aureus, Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Manual and automated nucleic acid extraction workflows were analysed separately. Diagnostic performance, agreement metrics, and discordant paired results were assessed using a contact plate culture as the microbiological comparator. Results: No LAMP-negative/RODAC-positive pairs were observed. Positive percent agreement (PPA) relative to contact plate culture was therefore 100% in the subgroups evaluated. Relative specificity ranged from 90.9% to 98.6%, while overall accuracy ranged from 93.8% to 98.6%. Discordant results were exclusively LAMP-positive/contact plate-negative and were more frequent for S. aureus and P. aeruginosa. Selective culture verification supported several LAMP-positive findings not recovered by routine contact plates. Conclusions: LAMP showed high negative agreement, high specificity, and rapid target-specific detection of selected nosocomial pathogens on hospital surfaces. It may complement conventional cultures in environmental surveillance, particularly when timely feedback is needed to guide infection-prevention and sanitation-monitoring strategies.