Dipartimento di Medicina Veterinaria, Università degli Studi di Bari, 70010, Valenzano, Bari, Italy.
Dipartimento di Scienze Biomediche e Oncologia Umana, Università degli Studi di Bari, Bari, Italy.
Parasitol Res. 2020 Apr;119(4):1381-1386. doi: 10.1007/s00436-020-06627-1. Epub 2020 Feb 27.
The prevalence data of Leishmania infantum infection in cats are characterized by a large variability mainly attributed to the differences in diagnostic techniques. In the absence of consensus about the method of choice for diagnosing feline leishmaniosis, the performance of a new immunofluorescence antibody test (IFAT) was herein analytically described by the comparison with IFAT commonly used for the diagnosis of canine leishmaniosis (i.e., IFAT-OIE) and a laboratory enzyme-linked immunosorbent assay (ELISA). Sera of cats living in visceral leishmaniosis-endemic (n = 105) and visceral leishmaniosis-non-endemic (n = 50) areas were tested by the above methodologies and real-time PCR (qPCR). The most frequent result was represented by triple negativity to the three tests (IFAT-OIE, ELISA, and qPCR) in 42.9% and 80% cats from endemic and non-endemic areas, respectively. Bayes latent class analysis gave an output probability of 34.1% (posterior standard deviation, psd = 5.4%) of true L. infantum cases (TCL) which represent the true estimated prevalence of infection. The sensitivity of each variable contributing to define the TCL was 24% (psd = 6.3%) for qPCR, 78.8% (psd = 8.7%) for ELISA and 91.8% (psd = 5.2%) for IFAT-OIE. The probability to be a TCL was 94.5% for the sample from an endemic area. The cross-validation of the new IFAT by a logistic model correctly identified as positive 80.7% of subjects defined as TCL and negative 89.9% as not TCL, respectively, by the Bayesian model. The study results estimate a good accuracy of the IFAT in predicting cats exposed to L. infantum. Therefore, this procedure may be beneficial for screening cat populations for a better understanding of the epidemiology of feline leishmaniosis.
猫感染利什曼原虫的流行数据的特点是具有很大的可变性，主要归因于诊断技术的差异。在没有关于诊断猫利什曼病的首选方法的共识的情况下，本文通过与常用于诊断犬利什曼病的免疫荧光抗体试验（IFAT-OIE）和实验室酶联免疫吸附试验（ELISA）的比较，对新的免疫荧光抗体试验（IFAT）的分析性能进行了描述。用上述方法和实时聚合酶链反应（qPCR）检测生活在内脏利什曼病流行（n=105）和非流行（n=50）地区的猫的血清。最常见的结果是，在分别来自流行和非流行地区的 42.9%和 80%的猫中，三种检测方法（IFAT-OIE、ELISA 和 qPCR）均为三重阴性。贝叶斯潜在类别分析得出 34.1%（后验标准偏差，psd=5.4%）的真实 L. infantum 病例（TCL）的输出概率，代表感染的真实估计流行率。定义 TCL 的每个变量的敏感性分别为 qPCR 为 24%（psd=6.3%）、ELISA 为 78.8%（psd=8.7%）和 IFAT-OIE 为 91.8%（psd=5.2%）。来自流行地区的样本成为 TCL 的概率为 94.5%。新 IFAT 的逻辑模型交叉验证通过贝叶斯模型分别正确地将 80.7%的被定义为 TCL 的对象识别为阳性，将 89.9%的被定义为非 TCL 的对象识别为阴性。研究结果估计 IFAT 在预测暴露于 L. infantum 的猫方面具有良好的准确性。因此，该程序可能有助于筛选猫群，以更好地了解猫利什曼病的流行病学。
