Quinnell R J, Courtenay O, Davidson S, Garcez L, Lambson B, Ramos P, Shaw J J, Shaw M A, Dye C
School of Biology, University of Leeds, UK.
Parasitology. 2001 Mar;122(Pt 3):253-61. doi: 10.1017/s0031182001007363.
The sensitivity and specificity of PCR, serology (ELISA) and lymphoproliferative response to Leishmania antigen for the detection of Leishmania infantum infection were evaluated in a cohort of 126 dogs exposed to natural infection in Brazil. For PCR, Leishmania DNA from bone-marrow was amplified with both minicircle and ribosomal primers. The infection status and time of infection of each dog were estimated from longitudinal data. The sensitivity of PCR in parasite-positive samples was 98%. However, the overall sensitivity of PCR in post-infection samples, from dogs with confirmed infection, was only 68%. The sensitivity of PCR varied during the course of infection, being highest (78-88%) 0-135 days post-infection and declining to around 50% after 300 days. The sensitivity of PCR also varied between dogs, and was highest in sick dogs. The sensitivity of serology was similar in parasite-positive (84%), PCR-positive (86%) and post-infection (88%) samples. The sensitivity of serology varied during the course of infection, being lowest at the time of infection and high (93-100%) thereafter. Problems in determining the specificity of serology are discussed. The sensitivity and specificity of cellular responsiveness were low. These data suggest that PCR is most useful in detecting active or symptomatic infection, and that serology can be a more sensitive technique for the detection of all infected dogs.
在巴西一组126只暴露于自然感染的犬中，评估了聚合酶链反应（PCR）、血清学（酶联免疫吸附测定，ELISA）和对利什曼原虫抗原的淋巴细胞增殖反应检测婴儿利什曼原虫感染的敏感性和特异性。对于PCR，使用微环引物和核糖体引物扩增来自骨髓的利什曼原虫DNA。根据纵向数据估计每只犬的感染状态和感染时间。PCR在寄生虫阳性样本中的敏感性为98%。然而，PCR在确诊感染犬的感染后样本中的总体敏感性仅为68%。PCR的敏感性在感染过程中有所变化，感染后0至135天最高（78 - 88%），300天后降至约50%。PCR的敏感性在不同犬之间也有所不同，病犬中最高。血清学在寄生虫阳性（84%）、PCR阳性（86%）和感染后（88%）样本中的敏感性相似。血清学的敏感性在感染过程中有所变化，感染时最低，此后较高（93 - 100%）。讨论了确定血清学特异性方面的问题。细胞反应性的敏感性和特异性较低。这些数据表明，PCR在检测活动性或症状性感染方面最有用，而血清学对于检测所有感染犬可能是一种更敏感的技术。
