Leptospirosis is an emerging worldwide zoonosis with a changing epidemiology responsible for an acute disease in humans and dogs. A better knowledge of the responsible bacterium Leptospira and in particular its various serovars and serogroups prevalence is essential for better diagnosis and prevention of the disease. The gold standard for leptospirosis diagnosis is the Microscopic Agglutination Test (MAT) but it requires long and fastidious laboratory work and sometimes results in controversial data. For these reasons, PCR-based techniques for detection of pathogenic leptospiral DNA in biological samples are currently replacing the MAT. However, these strategies do not provide any information regarding the infecting serovar or serogroup. In this study, an optimized genotyping method is described to allow the identification of Leptospira ssp. directly at serovars level using DNA extracted from canine blood and urine. 16S rDNA, Variable Number Tandem Repeat (VNTR) and Multispacer Sequence Typing (MST) protocols were adapted to biological samples. Eighty-eight DNA samples were analyzed from 72 different European canine clinical cases of leptospirosis confirmed by real-time PCR. 92% of DNA samples with Ct values below 34 were fully typed, and typing success decreased to about 30% for the other samples. Typing failure also showed a specie-specific correlation, with 63% of complete typing for L. interrogans and only 40% for L. kirschneri. Additionally, an exact match was observed between serological and molecular data for the few investigated cases where MAT data were available. This methodology is a suitable alternative to the MAT for determining the infecting serovar when Leptospira DNA from blood or urine is detected at Ct values below 34, contributing to clinical surveillance of leptospirosis.

钩端螺旋体病是一种新兴的世界范围人畜共患病，流行病学变化导致人类和狗的急性疾病。对负责的钩端螺旋体细菌有更好的了解尤其是其各种血清和血清群的流行对更好地诊断和预防该疾病至关重要。钩端螺旋体病诊断的金标准是显微镜凝集试验（MAT），但它需要长时间和严格的实验室工作，有时会引起争议的数据。由于这些原因，用于检测生物样品中致病性钩端螺旋体DNA的基于PCR的技术目前正在取代MAT。但是，这些策略没有提供有关感染血清或血清群的任何信息。在这项研究中，描述了一种优化的基因分型方法，可以鉴定钩端螺旋体ssp。直接从血清和尿液中提取DNA到血清水平。将16S rDNA，可变数目串联重复序列（VNTR）和多间隔子序列分型（MST）方案适用于生物样品。通过实时PCR确证了来自72个欧洲犬钩端螺旋体病临床病例的88个DNA样品。Ct值低于34的DNA样品中有92％被完全分型，而其他样品的分型成功率降至30％左右。打字失败还表现出特定种类的相关性，询问者乳杆菌的完全分型为63％，克氏杆菌为40％。此外，在少数可获得MAT数据的研究病例中，血清学和分子数据之间也存在精确匹配。当检测到血液或尿液中的钩端螺旋体DNA的Ct值低于34时，该方法是MAT确定感染血清型的合适方法，有助于临床监测钩端螺旋体病。