Data for: Comparison of multiplex tandem real-time PCR panel with reference real-time PCR molecular diagnostic assays for detection of Giardia intestinalis and Tritrichomonas foetus in cats

Giardia intestinalis and Tritrichomonas foetus are frequent enteric protozoan parasites of the gastrointestinal track of domestic cats. Because of different treatment options for the parasites, confirmation of presence of one or both pathogens is necessary. The PCR based assays are suitable for differential diagnosis. We evaluated performance of Small Animal Diarrhoea panel, a multiplex tandem real-time PCR (MT-PCR) assay, that detects DNA of both G. intestinalis and T. foetus. The sensitivity and specificity were compared to reference real-time PCR assays using 105 faecal samples, 39.05% (n = 41) positive for G. intestinalis and 30.48% (n = 32) were positive for T. foetus. The faecal samples positive for T. foetus had a high proportion of late amplifiers, determined by an arbitrary threshold of Ct-values > 35. On the other hand, only one G. intestinalis positive sample was considered a late amplifier. For G. intestinalis DNA, the MT-PCR assay had 95.1% sensitivity and 92.1% specificity. For T. foetus DNA, the MT-PCR assay had 41.9% sensitivity and 100.0% specificity. To evaluate the interlaboratory reproducibility of the MT-PCR assay, results were compared in two different laboratories and found to be in a very good agreement (Kappa= 0.9). Further analysis of the DNA using conventional PCR determined presence of G. intestinalis Assemblage F and T. foetus genotype ‘feline’. In conclusion, the MT-PCR Small Animal Diarrhoea panel had a good and poor performance against reference assays for G. intestinalis and T. foetus, respectively. The assay is suitable for detection and differential diagnosis of G. intestinalis and moderate to high burdens of T. foetus in small animal clinical practice.肠道贾第鞭毛虫（Giardia intestinalis）和胎儿三毛滴虫（Tritrichomonas foetus）是寄生于家猫胃肠道的常见肠道原生寄生虫。由于这两种寄生虫的治疗方案存在差异，因此确认其中一种或两种病原体的感染情况十分必要。基于聚合酶链式反应（PCR）的检测方法适用于该类病原体的鉴别诊断。本研究评估了小动物腹泻检测试剂盒（Small Animal Diarrhoea panel）——一种可同时检测贾第鞭毛虫和胎儿三毛滴虫DNA的多重串联实时荧光定量PCR（MT-PCR）检测体系——的检测性能。以105份粪便样本为研究对象，将该检测体系的灵敏度与特异性与参比实时PCR检测方法进行对比：其中39.05%（n=41）的样本呈贾第鞭毛虫阳性，30.48%（n=32）的样本呈胎儿三毛滴虫阳性。胎儿三毛滴虫阳性样本中，以任意阈值Ct值>35判定的延迟扩增样本占比极高；而贾第鞭毛虫阳性样本中，仅1份被判定为延迟扩增样本。针对贾第鞭毛虫DNA，该MT-PCR检测体系的灵敏度为95.1%，特异性为92.1%；针对胎儿三毛滴虫DNA，该MT-PCR检测体系的灵敏度为41.9%，特异性为100.0%。为评估该MT-PCR检测体系的室间重复性，本研究在两家不同实验室开展平行检测并对比结果，发现二者一致性极佳（Kappa值=0.9）。通过常规PCR对样本DNA进行进一步分型分析，确认检出的贾第鞭毛虫为组装型F（Assemblage F），胎儿三毛滴虫为猫源基因型（'feline'）。综上，相较于参比检测方法，该MT-PCR小动物腹泻检测试剂盒对贾第鞭毛虫的检测性能良好，而对胎儿三毛滴虫的检测性能欠佳。该检测体系适用于小动物临床实践中贾第鞭毛虫的检测与鉴别诊断，以及中至高载量胎儿三毛滴虫的感染检测。