title: A comparison of the reliability of two gene targets in loop-mediated isothermal amplification assays for detecting leptospiral DNA in canine urine.
abstract: We compared 2 novel loop-mediated isothermal amplification (LAMP) assays that target either the 16S ribosomal RNA ( rrs) gene or the gene encoding a 32-kDa leptospiral lipoprotein ( lipL32) in order to assess the effect of the target on the accuracy of the LAMP assays. The most sensitive assay was the rrs assay with a limit of detection (LOD) of 1.2 × 101genome equivalents per reaction. The novel lipL32 assay showed an LOD of 1.2 × 102genome equivalents per reaction. Both assays showed adequate specificity when tested against a collection of bacteria commonly found in voided canine urine. However, when field samples were assayed, the rrs assays gave many false-positive results and a poor positive predictive value of 8.33%. In conclusion, even if the LAMP assay is used in low prevalence areas, the lipL32 assay would be preferable. Conversely, the higher analytical sensitivity of the rrs assay could be effectively used as a screening test in endemic areas with high disease prevalence, followed by confirmation of the positive results using the lipL32 assay.
authors.affiliation: Department of Veterinary Medical Sciences, Alma Mater Studiorum, University of Bologna, Ozzano dell'Emilia, Bologna, Italy (Gentilini, Zanoni, Zambon).|Genefast srl, Valsamoggia, Bologna, Italy (Turba).
authors.forename: Fabio
authors.initials: F
authors.lastname: Gentilini
authors.affiliation: Department of Veterinary Medical Sciences, Alma Mater Studiorum, University of Bologna, Ozzano dell'Emilia, Bologna, Italy (Gentilini, Zanoni, Zambon).|Genefast srl, Valsamoggia, Bologna, Italy (Turba).
authors.forename: Renato Giulio
authors.initials: RG
authors.lastname: Zanoni
authors.affiliation: Department of Veterinary Medical Sciences, Alma Mater Studiorum, University of Bologna, Ozzano dell'Emilia, Bologna, Italy (Gentilini, Zanoni, Zambon).|Genefast srl, Valsamoggia, Bologna, Italy (Turba).
authors.forename: Elisa
authors.initials: E
authors.lastname: Zambon
authors.affiliation: Department of Veterinary Medical Sciences, Alma Mater Studiorum, University of Bologna, Ozzano dell'Emilia, Bologna, Italy (Gentilini, Zanoni, Zambon).|Genefast srl, Valsamoggia, Bologna, Italy (Turba).
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Turba
mesh_terms: D000818:Animals; D017931:DNA Primers; D004283:Dog Diseases / Q000175:diagnosis* / Q000382:microbiology / Q000652:urine; D004285:Dogs; D007919:Leptospira / Q000235:genetics / Q000302:isolation & purification*; D007922:Leptospirosis / Q000175:diagnosis / Q000662:veterinary*; D057230:Limit of Detection; D008074:Lipoproteins / Q000235:genetics / Q000302:isolation & purification; D021141:Nucleic Acid Amplification Techniques / Q000662:veterinary*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012680:Sensitivity and Specificity
chemical_list: D017931:DNA Primers; D008074:Lipoproteins; D012336:RNA, Ribosomal, 16S
keywords: 16S rRNA; Leptospira; dogs; lipL32; loop-mediated isothermal amplification; urine