Diagnostic Performance of Two Commercial qPCR Kits for Leptospira spp. Detection

Early confirmation of leptospirosis is essential for prompt antimicrobial treatment, and PCR-based diagnosis has been reported as a highly sensitive method during the acute phase in the first week since the symptom's onset. We evaluated the diagnostic performance of two commercial real-time PCR assays-Viasure Leptospira Real-Time PCR (Certest Biotec, Spain) and Genesig Advanced Leptospira spp. (Primerdesign, UK) against an in-house qPCR assay targeting lipL32 as the reference method. A retrospective comparative evaluation was conducted on 235 human EDTA-blood samples obtained during the acute phase of clinical presentation suspected of leptospirosis. The in-house qPCR reference assay detected 55 positive and 180 negative samples, and both commercial kits accurately classified every specimen, achieving 100% sensitivity (95% CI: 93.5-100), 100% specificity (95% CI: 98.0-100), and 100% overall accuracy. In conclusion, both commercial qPCR kits offer high accuracy for the early detection of pathogenic Leptospira in human blood samples.