Direct test over the gut material from triatomine vectors and xenodiagnosis over mammalian hosts are classical techniques for Trypanosoma cruzi parasitological diagnosis. Nevertheless, negative results can be a source of uncertainty. Experimental models have allowed evaluating the tissue invasion of different strains of T. cruzi, but conventional techniques for tissue biopsies involve time-consuming and elaborated procedures and have low sensitivity. Gut material of collected triatomines (microscopically negative) (n = 114), material of mammal xenodiagnoses (microscopically negative) (n = 138), and biopsy material (microscopically negative) from experimentally infected animals (n = 34) with isolates from endemic areas of Chagas’ disease from Venezuela were used for DNA extraction and PCR for the amplification of kinetoplast DNA (kDNA) and satellite DNA (sDNA) of T. cruzi. Positive PCR was observed in 53.6% of collected triatomine material, 15.8% of parasitological negative xenodiagnosis material, and 70.6% in biopsies, revealing underestimation by the parasitological tests and the valour of this analysis with preserved material. Anzoátegui was the state with the highest percentage of infection, and the triatomine species Rhodnius prolixus and Panstrongylus geniculatus had the highest percentages of infection. Didelphis marsupialis and Canis familiaris were the most infected by T. cruzi revealed by PCR of xenodiagnosis material. In addition, the PCR technique allowed demonstrating the invasion of T. cruzi in all tissues analyzed, constituting a molecular marker of tissue invasion.

对来自triatomine 载体的肠道材料的直接测试和对哺乳动物宿主的异种诊断是克氏锥虫寄生虫学诊断的经典技术。然而，负面结果可能是不确定性的来源。实验模型已经允许评估不同品系的组织侵犯牛逼。cruzi，但传统的组织活检技术涉及耗时且复杂的程序，并且灵敏度低。收集到的 triatomines 的肠道材料（显微镜下呈阴性）（n  = 114）、哺乳动物异种 诊断材料（显微镜下呈阴性）（n = 138）和来自实验感染动物的活检材料（显微镜下呈阴性）（n = 34）与来自委内瑞拉恰加斯病的流行区的分离物用于DNA提取和PCR对动基体DNA（kDNA）和卫星DNA的（SDNA）的扩增Ť。克氏锥虫。在 53.6% 的收集到的 triatomine 材料、15.8% 的寄生虫学阴性异种诊断材料和 70.6% 的活检中观察到阳性 PCR，这表明寄生虫学测试低估了这种分析对保存材料的价值。Anzoátegui 是感染率最高的州，而Triatomine物种Rhodnius prolixus和Panstrongylus geniculatus的感染率最高。有袋袋鼠和家犬被T感染最多。通过异种诊断材料的 PCR 揭示了cruzi。此外，PCR 技术允许证明T的入侵。cruzi在分析的所有组织中，构成组织侵袭的分子标记。