Department of Medicine, Swiss Tropical and Public Health Institute, Basel, Switzerland.
University of Basel, Basel, Switzerland.
PLoS Negl Trop Dis. 2022 Jun 6;16(6):e0009876. doi: 10.1371/journal.pntd.0009876. eCollection 2022 Jun.
Leptospirosis is among the most important zoonotic diseases in (sub-)tropical countries. The research objective was to evaluate the accuracy of the Serion IgM ELISA EST125M against the Microscopic Agglutination Test (MAT = imperfect reference test); to assess its ability to diagnose acute leptospirosis infections and to detect previous exposure to leptospires in an endemic setting. In addition, to estimate the overall Leptospira spp. seroprevalence in the Wiwa indigenous population in North-East Colombia. We analysed serum samples from confirmed leptospirosis patients from the Netherlands (N = 14), blood donor sera from Switzerland (N = 20), and sera from a cross-sectional study in Colombia (N = 321). All leptospirosis ELISA-positive, and a random of negative samples from Colombia were tested by the MAT for confirmation. The ELISA performed with a sensitivity of 100% (95% CI 77% - 100%) and a specificity of 100% (95% CI 83% - 100%) based on MAT confirmed Leptospira spp. positive and negative samples. In the cross-sectional study in Colombia, the ELISA performed with a sensitivity of 100% (95% CI 2-100%) and a specificity of 21% (95% CI 15-28%). Assuming a 5% Leptospira spp. seroprevalence in this population, the positive predictive value was 6% and the negative predictive value 100%. The Leptospira spp. seroprevalence in the Wiwas tested by the ELISA was 39%; however, by MAT only 0.3%. The ELISA is suitable to diagnose leptospirosis in acutely ill patients in Europe several days after onset of disease. For cross-sectional studies it is not recommended due to its low specificity. Despite the evidence of a high leptospirosis prevalence in other study areas and populations in Colombia, the Wiwa do not seem to be highly exposed to Leptospira spp.. Nevertheless, leptospirosis should be considered and tested in patients presenting with febrile illness.
钩端螺旋体病是（亚热带）热带国家最重要的人畜共患病之一。本研究的目的是评估 Serion IgM ELISA EST125M 对显微镜凝集试验（MAT=不完善参考试验）的准确性；评估其诊断急性钩端螺旋体病感染的能力，并在流行地区检测对钩端螺旋体的既往暴露。此外，还估计了哥伦比亚东北部 Wiwa 土著人群中钩端螺旋体属的总体血清流行率。我们分析了来自荷兰确诊的钩端螺旋体病患者（N=14）、瑞士献血者血清（N=20）和哥伦比亚横断面研究（N=321）的血清样本。所有钩端螺旋体病 ELISA 阳性和随机阴性的哥伦比亚样本均用 MAT 进行确认检测。基于 MAT 确认的阳性和阴性钩端螺旋体属样本，该 ELISA 的敏感性为 100%（95%CI77%-100%），特异性为 100%（95%CI83%-100%）。在哥伦比亚的横断面研究中，ELISA 的敏感性为 100%（95%CI2%-100%），特异性为 21%（95%CI15%-28%）。假设该人群的钩端螺旋体属血清流行率为 5%，阳性预测值为 6%，阴性预测值为 100%。用 ELISA 检测 Wiwa 人群的钩端螺旋体属血清流行率为 39%，而用 MAT 检测仅为 0.3%。该 ELISA 适用于在疾病发作后几天内诊断欧洲急性患病患者的钩端螺旋体病。由于其特异性低，不建议用于横断面研究。尽管有证据表明在哥伦比亚的其他研究地区和人群中钩端螺旋体病的流行率较高，但 Wiwa 人群似乎并未高度暴露于钩端螺旋体属。然而，应考虑并测试出现发热性疾病的患者是否患有钩端螺旋体病。
